Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

29 files changed, 12102 insertions, 0 deletions

diff --git a/kernel/drivers/of/Kconfig b/kernel/drivers/of/Kconfig
new file mode 100644
index 000000000..07bb3c8f1
--- /dev/null
+++ b/kernel/drivers/of/Kconfig
@@ -0,0 +1,100 @@
+config DTC
+	bool
+
+config OF
+	bool
+
+menu "Device Tree and Open Firmware support"
+	depends on OF
+
+config OF_UNITTEST
+	bool "Device Tree runtime unit tests"
+	depends on OF_IRQ && OF_EARLY_FLATTREE
+	select OF_RESOLVE
+	help
+	  This option builds in test cases for the device tree infrastructure
+	  that are executed once at boot time, and the results dumped to the
+	  console.
+
+	  If unsure, say N here, but this option is safe to enable.
+
+config OF_FLATTREE
+	bool
+	select DTC
+	select LIBFDT
+	select CRC32
+
+config OF_EARLY_FLATTREE
+	bool
+	select OF_FLATTREE
+
+config OF_PROMTREE
+	bool
+
+# Hardly any platforms need this.  It is safe to select, but only do so if you
+# need it.
+config OF_DYNAMIC
+	bool "Support for dynamic device trees" if OF_UNITTEST
+	help
+	  On some platforms, the device tree can be manipulated at runtime.
+	  While this option is selected automatically on such platforms, you
+	  can enable it manually to improve device tree unit test coverage.
+
+config OF_ADDRESS
+	def_bool y
+	depends on !SPARC
+	select OF_ADDRESS_PCI if PCI
+
+config OF_ADDRESS_PCI
+	bool
+
+config OF_IRQ
+	def_bool y
+	depends on !SPARC && IRQ_DOMAIN
+
+config OF_NET
+	depends on NETDEVICES
+	def_bool y
+
+config OF_MDIO
+	def_tristate PHYLIB
+	depends on PHYLIB
+	help
+	  OpenFirmware MDIO bus (Ethernet PHY) accessors
+
+config OF_PCI
+	def_tristate PCI
+	depends on PCI
+	help
+	  OpenFirmware PCI bus accessors
+
+config OF_PCI_IRQ
+	def_tristate PCI
+	depends on OF_PCI && OF_IRQ
+	help
+	  OpenFirmware PCI IRQ routing helpers
+
+config OF_MTD
+	depends on MTD
+	def_bool y
+
+config OF_RESERVED_MEM
+	depends on OF_EARLY_FLATTREE
+	bool
+	help
+	  Helpers to allow for reservation of memory regions
+
+config OF_RESOLVE
+	bool
+
+config OF_OVERLAY
+	bool "Device Tree overlays"
+	select OF_DYNAMIC
+	select OF_RESOLVE
+	help
+	  Overlays are a method to dynamically modify part of the kernel's
+	  device tree with dynamically loaded data.
+	  While this option is selected automatically when needed, you can
+	  enable it manually to improve device tree unit test coverage.
+
+endmenu # OF
diff --git a/kernel/drivers/of/Makefile b/kernel/drivers/of/Makefile
new file mode 100644
index 000000000..fcacb186a
--- /dev/null
+++ b/kernel/drivers/of/Makefile
@@ -0,0 +1,21 @@
+obj-y = base.o device.o platform.o
+obj-$(CONFIG_OF_DYNAMIC) += dynamic.o
+obj-$(CONFIG_OF_FLATTREE) += fdt.o
+obj-$(CONFIG_OF_EARLY_FLATTREE) += fdt_address.o
+obj-$(CONFIG_OF_PROMTREE) += pdt.o
+obj-$(CONFIG_OF_ADDRESS)  += address.o
+obj-$(CONFIG_OF_IRQ)    += irq.o
+obj-$(CONFIG_OF_NET)	+= of_net.o
+obj-$(CONFIG_OF_UNITTEST) += unittest.o
+obj-$(CONFIG_OF_MDIO)	+= of_mdio.o
+obj-$(CONFIG_OF_PCI)	+= of_pci.o
+obj-$(CONFIG_OF_PCI_IRQ)  += of_pci_irq.o
+obj-$(CONFIG_OF_MTD)	+= of_mtd.o
+obj-$(CONFIG_OF_RESERVED_MEM) += of_reserved_mem.o
+obj-$(CONFIG_OF_RESOLVE)  += resolver.o
+obj-$(CONFIG_OF_OVERLAY) += overlay.o
+
+obj-$(CONFIG_OF_UNITTEST) += unittest-data/
+
+CFLAGS_fdt.o = -I$(src)/../../scripts/dtc/libfdt
+CFLAGS_fdt_address.o = -I$(src)/../../scripts/dtc/libfdt
diff --git a/kernel/drivers/of/address.c b/kernel/drivers/of/address.c
new file mode 100644
index 000000000..6906a3f61
--- /dev/null
+++ b/kernel/drivers/of/address.c
@@ -0,0 +1,1021 @@
+
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/pci_regs.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+
+/* Max address size we deal with */
+#define OF_MAX_ADDR_CELLS	4
+#define OF_CHECK_ADDR_COUNT(na)	((na) > 0 && (na) <= OF_MAX_ADDR_CELLS)
+#define OF_CHECK_COUNTS(na, ns)	(OF_CHECK_ADDR_COUNT(na) && (ns) > 0)
+
+static struct of_bus *of_match_bus(struct device_node *np);
+static int __of_address_to_resource(struct device_node *dev,
+		const __be32 *addrp, u64 size, unsigned int flags,
+		const char *name, struct resource *r);
+
+/* Debug utility */
+#ifdef DEBUG
+static void of_dump_addr(const char *s, const __be32 *addr, int na)
+{
+	printk(KERN_DEBUG "%s", s);
+	while (na--)
+		printk(" %08x", be32_to_cpu(*(addr++)));
+	printk("\n");
+}
+#else
+static void of_dump_addr(const char *s, const __be32 *addr, int na) { }
+#endif
+
+/* Callbacks for bus specific translators */
+struct of_bus {
+	const char	*name;
+	const char	*addresses;
+	int		(*match)(struct device_node *parent);
+	void		(*count_cells)(struct device_node *child,
+				       int *addrc, int *sizec);
+	u64		(*map)(__be32 *addr, const __be32 *range,
+				int na, int ns, int pna);
+	int		(*translate)(__be32 *addr, u64 offset, int na);
+	unsigned int	(*get_flags)(const __be32 *addr);
+};
+
+/*
+ * Default translator (generic bus)
+ */
+
+static void of_bus_default_count_cells(struct device_node *dev,
+				       int *addrc, int *sizec)
+{
+	if (addrc)
+		*addrc = of_n_addr_cells(dev);
+	if (sizec)
+		*sizec = of_n_size_cells(dev);
+}
+
+static u64 of_bus_default_map(__be32 *addr, const __be32 *range,
+		int na, int ns, int pna)
+{
+	u64 cp, s, da;
+
+	cp = of_read_number(range, na);
+	s  = of_read_number(range + na + pna, ns);
+	da = of_read_number(addr, na);
+
+	pr_debug("OF: default map, cp=%llx, s=%llx, da=%llx\n",
+		 (unsigned long long)cp, (unsigned long long)s,
+		 (unsigned long long)da);
+
+	if (da < cp || da >= (cp + s))
+		return OF_BAD_ADDR;
+	return da - cp;
+}
+
+static int of_bus_default_translate(__be32 *addr, u64 offset, int na)
+{
+	u64 a = of_read_number(addr, na);
+	memset(addr, 0, na * 4);
+	a += offset;
+	if (na > 1)
+		addr[na - 2] = cpu_to_be32(a >> 32);
+	addr[na - 1] = cpu_to_be32(a & 0xffffffffu);
+
+	return 0;
+}
+
+static unsigned int of_bus_default_get_flags(const __be32 *addr)
+{
+	return IORESOURCE_MEM;
+}
+
+#ifdef CONFIG_OF_ADDRESS_PCI
+/*
+ * PCI bus specific translator
+ */
+
+static int of_bus_pci_match(struct device_node *np)
+{
+	/*
+ 	 * "pciex" is PCI Express
+	 * "vci" is for the /chaos bridge on 1st-gen PCI powermacs
+	 * "ht" is hypertransport
+	 */
+	return !strcmp(np->type, "pci") || !strcmp(np->type, "pciex") ||
+		!strcmp(np->type, "vci") || !strcmp(np->type, "ht");
+}
+
+static void of_bus_pci_count_cells(struct device_node *np,
+				   int *addrc, int *sizec)
+{
+	if (addrc)
+		*addrc = 3;
+	if (sizec)
+		*sizec = 2;
+}
+
+static unsigned int of_bus_pci_get_flags(const __be32 *addr)
+{
+	unsigned int flags = 0;
+	u32 w = be32_to_cpup(addr);
+
+	switch((w >> 24) & 0x03) {
+	case 0x01:
+		flags |= IORESOURCE_IO;
+		break;
+	case 0x02: /* 32 bits */
+	case 0x03: /* 64 bits */
+		flags |= IORESOURCE_MEM;
+		break;
+	}
+	if (w & 0x40000000)
+		flags |= IORESOURCE_PREFETCH;
+	return flags;
+}
+
+static u64 of_bus_pci_map(__be32 *addr, const __be32 *range, int na, int ns,
+		int pna)
+{
+	u64 cp, s, da;
+	unsigned int af, rf;
+
+	af = of_bus_pci_get_flags(addr);
+	rf = of_bus_pci_get_flags(range);
+
+	/* Check address type match */
+	if ((af ^ rf) & (IORESOURCE_MEM | IORESOURCE_IO))
+		return OF_BAD_ADDR;
+
+	/* Read address values, skipping high cell */
+	cp = of_read_number(range + 1, na - 1);
+	s  = of_read_number(range + na + pna, ns);
+	da = of_read_number(addr + 1, na - 1);
+
+	pr_debug("OF: PCI map, cp=%llx, s=%llx, da=%llx\n",
+		 (unsigned long long)cp, (unsigned long long)s,
+		 (unsigned long long)da);
+
+	if (da < cp || da >= (cp + s))
+		return OF_BAD_ADDR;
+	return da - cp;
+}
+
+static int of_bus_pci_translate(__be32 *addr, u64 offset, int na)
+{
+	return of_bus_default_translate(addr + 1, offset, na - 1);
+}
+#endif /* CONFIG_OF_ADDRESS_PCI */
+
+#ifdef CONFIG_PCI
+const __be32 *of_get_pci_address(struct device_node *dev, int bar_no, u64 *size,
+			unsigned int *flags)
+{
+	const __be32 *prop;
+	unsigned int psize;
+	struct device_node *parent;
+	struct of_bus *bus;
+	int onesize, i, na, ns;
+
+	/* Get parent & match bus type */
+	parent = of_get_parent(dev);
+	if (parent == NULL)
+		return NULL;
+	bus = of_match_bus(parent);
+	if (strcmp(bus->name, "pci")) {
+		of_node_put(parent);
+		return NULL;
+	}
+	bus->count_cells(dev, &na, &ns);
+	of_node_put(parent);
+	if (!OF_CHECK_ADDR_COUNT(na))
+		return NULL;
+
+	/* Get "reg" or "assigned-addresses" property */
+	prop = of_get_property(dev, bus->addresses, &psize);
+	if (prop == NULL)
+		return NULL;
+	psize /= 4;
+
+	onesize = na + ns;
+	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) {
+		u32 val = be32_to_cpu(prop[0]);
+		if ((val & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0)) {
+			if (size)
+				*size = of_read_number(prop + na, ns);
+			if (flags)
+				*flags = bus->get_flags(prop);
+			return prop;
+		}
+	}
+	return NULL;
+}
+EXPORT_SYMBOL(of_get_pci_address);
+
+int of_pci_address_to_resource(struct device_node *dev, int bar,
+			       struct resource *r)
+{
+	const __be32	*addrp;
+	u64		size;
+	unsigned int	flags;
+
+	addrp = of_get_pci_address(dev, bar, &size, &flags);
+	if (addrp == NULL)
+		return -EINVAL;
+	return __of_address_to_resource(dev, addrp, size, flags, NULL, r);
+}
+EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
+
+int of_pci_range_parser_init(struct of_pci_range_parser *parser,
+				struct device_node *node)
+{
+	const int na = 3, ns = 2;
+	int rlen;
+
+	parser->node = node;
+	parser->pna = of_n_addr_cells(node);
+	parser->np = parser->pna + na + ns;
+
+	parser->range = of_get_property(node, "ranges", &rlen);
+	if (parser->range == NULL)
+		return -ENOENT;
+
+	parser->end = parser->range + rlen / sizeof(__be32);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_pci_range_parser_init);
+
+struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
+						struct of_pci_range *range)
+{
+	const int na = 3, ns = 2;
+
+	if (!range)
+		return NULL;
+
+	if (!parser->range || parser->range + parser->np > parser->end)
+		return NULL;
+
+	range->pci_space = parser->range[0];
+	range->flags = of_bus_pci_get_flags(parser->range);
+	range->pci_addr = of_read_number(parser->range + 1, ns);
+	range->cpu_addr = of_translate_address(parser->node,
+				parser->range + na);
+	range->size = of_read_number(parser->range + parser->pna + na, ns);
+
+	parser->range += parser->np;
+
+	/* Now consume following elements while they are contiguous */
+	while (parser->range + parser->np <= parser->end) {
+		u32 flags, pci_space;
+		u64 pci_addr, cpu_addr, size;
+
+		pci_space = be32_to_cpup(parser->range);
+		flags = of_bus_pci_get_flags(parser->range);
+		pci_addr = of_read_number(parser->range + 1, ns);
+		cpu_addr = of_translate_address(parser->node,
+				parser->range + na);
+		size = of_read_number(parser->range + parser->pna + na, ns);
+
+		if (flags != range->flags)
+			break;
+		if (pci_addr != range->pci_addr + range->size ||
+		    cpu_addr != range->cpu_addr + range->size)
+			break;
+
+		range->size += size;
+		parser->range += parser->np;
+	}
+
+	return range;
+}
+EXPORT_SYMBOL_GPL(of_pci_range_parser_one);
+
+/*
+ * of_pci_range_to_resource - Create a resource from an of_pci_range
+ * @range:	the PCI range that describes the resource
+ * @np:		device node where the range belongs to
+ * @res:	pointer to a valid resource that will be updated to
+ *              reflect the values contained in the range.
+ *
+ * Returns EINVAL if the range cannot be converted to resource.
+ *
+ * Note that if the range is an IO range, the resource will be converted
+ * using pci_address_to_pio() which can fail if it is called too early or
+ * if the range cannot be matched to any host bridge IO space (our case here).
+ * To guard against that we try to register the IO range first.
+ * If that fails we know that pci_address_to_pio() will do too.
+ */
+int of_pci_range_to_resource(struct of_pci_range *range,
+			     struct device_node *np, struct resource *res)
+{
+	int err;
+	res->flags = range->flags;
+	res->parent = res->child = res->sibling = NULL;
+	res->name = np->full_name;
+
+	if (res->flags & IORESOURCE_IO) {
+		unsigned long port;
+		err = pci_register_io_range(range->cpu_addr, range->size);
+		if (err)
+			goto invalid_range;
+		port = pci_address_to_pio(range->cpu_addr);
+		if (port == (unsigned long)-1) {
+			err = -EINVAL;
+			goto invalid_range;
+		}
+		res->start = port;
+	} else {
+		res->start = range->cpu_addr;
+	}
+	res->end = res->start + range->size - 1;
+	return 0;
+
+invalid_range:
+	res->start = (resource_size_t)OF_BAD_ADDR;
+	res->end = (resource_size_t)OF_BAD_ADDR;
+	return err;
+}
+#endif /* CONFIG_PCI */
+
+/*
+ * ISA bus specific translator
+ */
+
+static int of_bus_isa_match(struct device_node *np)
+{
+	return !strcmp(np->name, "isa");
+}
+
+static void of_bus_isa_count_cells(struct device_node *child,
+				   int *addrc, int *sizec)
+{
+	if (addrc)
+		*addrc = 2;
+	if (sizec)
+		*sizec = 1;
+}
+
+static u64 of_bus_isa_map(__be32 *addr, const __be32 *range, int na, int ns,
+		int pna)
+{
+	u64 cp, s, da;
+
+	/* Check address type match */
+	if ((addr[0] ^ range[0]) & cpu_to_be32(1))
+		return OF_BAD_ADDR;
+
+	/* Read address values, skipping high cell */
+	cp = of_read_number(range + 1, na - 1);
+	s  = of_read_number(range + na + pna, ns);
+	da = of_read_number(addr + 1, na - 1);
+
+	pr_debug("OF: ISA map, cp=%llx, s=%llx, da=%llx\n",
+		 (unsigned long long)cp, (unsigned long long)s,
+		 (unsigned long long)da);
+
+	if (da < cp || da >= (cp + s))
+		return OF_BAD_ADDR;
+	return da - cp;
+}
+
+static int of_bus_isa_translate(__be32 *addr, u64 offset, int na)
+{
+	return of_bus_default_translate(addr + 1, offset, na - 1);
+}
+
+static unsigned int of_bus_isa_get_flags(const __be32 *addr)
+{
+	unsigned int flags = 0;
+	u32 w = be32_to_cpup(addr);
+
+	if (w & 1)
+		flags |= IORESOURCE_IO;
+	else
+		flags |= IORESOURCE_MEM;
+	return flags;
+}
+
+/*
+ * Array of bus specific translators
+ */
+
+static struct of_bus of_busses[] = {
+#ifdef CONFIG_OF_ADDRESS_PCI
+	/* PCI */
+	{
+		.name = "pci",
+		.addresses = "assigned-addresses",
+		.match = of_bus_pci_match,
+		.count_cells = of_bus_pci_count_cells,
+		.map = of_bus_pci_map,
+		.translate = of_bus_pci_translate,
+		.get_flags = of_bus_pci_get_flags,
+	},
+#endif /* CONFIG_OF_ADDRESS_PCI */
+	/* ISA */
+	{
+		.name = "isa",
+		.addresses = "reg",
+		.match = of_bus_isa_match,
+		.count_cells = of_bus_isa_count_cells,
+		.map = of_bus_isa_map,
+		.translate = of_bus_isa_translate,
+		.get_flags = of_bus_isa_get_flags,
+	},
+	/* Default */
+	{
+		.name = "default",
+		.addresses = "reg",
+		.match = NULL,
+		.count_cells = of_bus_default_count_cells,
+		.map = of_bus_default_map,
+		.translate = of_bus_default_translate,
+		.get_flags = of_bus_default_get_flags,
+	},
+};
+
+static struct of_bus *of_match_bus(struct device_node *np)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(of_busses); i++)
+		if (!of_busses[i].match || of_busses[i].match(np))
+			return &of_busses[i];
+	BUG();
+	return NULL;
+}
+
+static int of_empty_ranges_quirk(struct device_node *np)
+{
+	if (IS_ENABLED(CONFIG_PPC)) {
+		/* To save cycles, we cache the result for global "Mac" setting */
+		static int quirk_state = -1;
+
+		/* PA-SEMI sdc DT bug */
+		if (of_device_is_compatible(np, "1682m-sdc"))
+			return true;
+
+		/* Make quirk cached */
+		if (quirk_state < 0)
+			quirk_state =
+				of_machine_is_compatible("Power Macintosh") ||
+				of_machine_is_compatible("MacRISC");
+		return quirk_state;
+	}
+	return false;
+}
+
+static int of_translate_one(struct device_node *parent, struct of_bus *bus,
+			    struct of_bus *pbus, __be32 *addr,
+			    int na, int ns, int pna, const char *rprop)
+{
+	const __be32 *ranges;
+	unsigned int rlen;
+	int rone;
+	u64 offset = OF_BAD_ADDR;
+
+	/* Normally, an absence of a "ranges" property means we are
+	 * crossing a non-translatable boundary, and thus the addresses
+	 * below the current not cannot be converted to CPU physical ones.
+	 * Unfortunately, while this is very clear in the spec, it's not
+	 * what Apple understood, and they do have things like /uni-n or
+	 * /ht nodes with no "ranges" property and a lot of perfectly
+	 * useable mapped devices below them. Thus we treat the absence of
+	 * "ranges" as equivalent to an empty "ranges" property which means
+	 * a 1:1 translation at that level. It's up to the caller not to try
+	 * to translate addresses that aren't supposed to be translated in
+	 * the first place. --BenH.
+	 *
+	 * As far as we know, this damage only exists on Apple machines, so
+	 * This code is only enabled on powerpc. --gcl
+	 */
+	ranges = of_get_property(parent, rprop, &rlen);
+	if (ranges == NULL && !of_empty_ranges_quirk(parent)) {
+		pr_debug("OF: no ranges; cannot translate\n");
+		return 1;
+	}
+	if (ranges == NULL || rlen == 0) {
+		offset = of_read_number(addr, na);
+		memset(addr, 0, pna * 4);
+		pr_debug("OF: empty ranges; 1:1 translation\n");
+		goto finish;
+	}
+
+	pr_debug("OF: walking ranges...\n");
+
+	/* Now walk through the ranges */
+	rlen /= 4;
+	rone = na + pna + ns;
+	for (; rlen >= rone; rlen -= rone, ranges += rone) {
+		offset = bus->map(addr, ranges, na, ns, pna);
+		if (offset != OF_BAD_ADDR)
+			break;
+	}
+	if (offset == OF_BAD_ADDR) {
+		pr_debug("OF: not found !\n");
+		return 1;
+	}
+	memcpy(addr, ranges + na, 4 * pna);
+
+ finish:
+	of_dump_addr("OF: parent translation for:", addr, pna);
+	pr_debug("OF: with offset: %llx\n", (unsigned long long)offset);
+
+	/* Translate it into parent bus space */
+	return pbus->translate(addr, offset, pna);
+}
+
+/*
+ * Translate an address from the device-tree into a CPU physical address,
+ * this walks up the tree and applies the various bus mappings on the
+ * way.
+ *
+ * Note: We consider that crossing any level with #size-cells == 0 to mean
+ * that translation is impossible (that is we are not dealing with a value
+ * that can be mapped to a cpu physical address). This is not really specified
+ * that way, but this is traditionally the way IBM at least do things
+ */
+static u64 __of_translate_address(struct device_node *dev,
+				  const __be32 *in_addr, const char *rprop)
+{
+	struct device_node *parent = NULL;
+	struct of_bus *bus, *pbus;
+	__be32 addr[OF_MAX_ADDR_CELLS];
+	int na, ns, pna, pns;
+	u64 result = OF_BAD_ADDR;
+
+	pr_debug("OF: ** translation for device %s **\n", of_node_full_name(dev));
+
+	/* Increase refcount at current level */
+	of_node_get(dev);
+
+	/* Get parent & match bus type */
+	parent = of_get_parent(dev);
+	if (parent == NULL)
+		goto bail;
+	bus = of_match_bus(parent);
+
+	/* Count address cells & copy address locally */
+	bus->count_cells(dev, &na, &ns);
+	if (!OF_CHECK_COUNTS(na, ns)) {
+		pr_debug("OF: Bad cell count for %s\n", of_node_full_name(dev));
+		goto bail;
+	}
+	memcpy(addr, in_addr, na * 4);
+
+	pr_debug("OF: bus is %s (na=%d, ns=%d) on %s\n",
+	    bus->name, na, ns, of_node_full_name(parent));
+	of_dump_addr("OF: translating address:", addr, na);
+
+	/* Translate */
+	for (;;) {
+		/* Switch to parent bus */
+		of_node_put(dev);
+		dev = parent;
+		parent = of_get_parent(dev);
+
+		/* If root, we have finished */
+		if (parent == NULL) {
+			pr_debug("OF: reached root node\n");
+			result = of_read_number(addr, na);
+			break;
+		}
+
+		/* Get new parent bus and counts */
+		pbus = of_match_bus(parent);
+		pbus->count_cells(dev, &pna, &pns);
+		if (!OF_CHECK_COUNTS(pna, pns)) {
+			printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
+			       of_node_full_name(dev));
+			break;
+		}
+
+		pr_debug("OF: parent bus is %s (na=%d, ns=%d) on %s\n",
+		    pbus->name, pna, pns, of_node_full_name(parent));
+
+		/* Apply bus translation */
+		if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop))
+			break;
+
+		/* Complete the move up one level */
+		na = pna;
+		ns = pns;
+		bus = pbus;
+
+		of_dump_addr("OF: one level translation:", addr, na);
+	}
+ bail:
+	of_node_put(parent);
+	of_node_put(dev);
+
+	return result;
+}
+
+u64 of_translate_address(struct device_node *dev, const __be32 *in_addr)
+{
+	return __of_translate_address(dev, in_addr, "ranges");
+}
+EXPORT_SYMBOL(of_translate_address);
+
+u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr)
+{
+	return __of_translate_address(dev, in_addr, "dma-ranges");
+}
+EXPORT_SYMBOL(of_translate_dma_address);
+
+const __be32 *of_get_address(struct device_node *dev, int index, u64 *size,
+		    unsigned int *flags)
+{
+	const __be32 *prop;
+	unsigned int psize;
+	struct device_node *parent;
+	struct of_bus *bus;
+	int onesize, i, na, ns;
+
+	/* Get parent & match bus type */
+	parent = of_get_parent(dev);
+	if (parent == NULL)
+		return NULL;
+	bus = of_match_bus(parent);
+	bus->count_cells(dev, &na, &ns);
+	of_node_put(parent);
+	if (!OF_CHECK_ADDR_COUNT(na))
+		return NULL;
+
+	/* Get "reg" or "assigned-addresses" property */
+	prop = of_get_property(dev, bus->addresses, &psize);
+	if (prop == NULL)
+		return NULL;
+	psize /= 4;
+
+	onesize = na + ns;
+	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++)
+		if (i == index) {
+			if (size)
+				*size = of_read_number(prop + na, ns);
+			if (flags)
+				*flags = bus->get_flags(prop);
+			return prop;
+		}
+	return NULL;
+}
+EXPORT_SYMBOL(of_get_address);
+
+#ifdef PCI_IOBASE
+struct io_range {
+	struct list_head list;
+	phys_addr_t start;
+	resource_size_t size;
+};
+
+static LIST_HEAD(io_range_list);
+static DEFINE_SPINLOCK(io_range_lock);
+#endif
+
+/*
+ * Record the PCI IO range (expressed as CPU physical address + size).
+ * Return a negative value if an error has occured, zero otherwise
+ */
+int __weak pci_register_io_range(phys_addr_t addr, resource_size_t size)
+{
+	int err = 0;
+
+#ifdef PCI_IOBASE
+	struct io_range *range;
+	resource_size_t allocated_size = 0;
+
+	/* check if the range hasn't been previously recorded */
+	spin_lock(&io_range_lock);
+	list_for_each_entry(range, &io_range_list, list) {
+		if (addr >= range->start && addr + size <= range->start + size) {
+			/* range already registered, bail out */
+			goto end_register;
+		}
+		allocated_size += range->size;
+	}
+
+	/* range not registed yet, check for available space */
+	if (allocated_size + size - 1 > IO_SPACE_LIMIT) {
+		/* if it's too big check if 64K space can be reserved */
+		if (allocated_size + SZ_64K - 1 > IO_SPACE_LIMIT) {
+			err = -E2BIG;
+			goto end_register;
+		}
+
+		size = SZ_64K;
+		pr_warn("Requested IO range too big, new size set to 64K\n");
+	}
+
+	/* add the range to the list */
+	range = kzalloc(sizeof(*range), GFP_KERNEL);
+	if (!range) {
+		err = -ENOMEM;
+		goto end_register;
+	}
+
+	range->start = addr;
+	range->size = size;
+
+	list_add_tail(&range->list, &io_range_list);
+
+end_register:
+	spin_unlock(&io_range_lock);
+#endif
+
+	return err;
+}
+
+phys_addr_t pci_pio_to_address(unsigned long pio)
+{
+	phys_addr_t address = (phys_addr_t)OF_BAD_ADDR;
+
+#ifdef PCI_IOBASE
+	struct io_range *range;
+	resource_size_t allocated_size = 0;
+
+	if (pio > IO_SPACE_LIMIT)
+		return address;
+
+	spin_lock(&io_range_lock);
+	list_for_each_entry(range, &io_range_list, list) {
+		if (pio >= allocated_size && pio < allocated_size + range->size) {
+			address = range->start + pio - allocated_size;
+			break;
+		}
+		allocated_size += range->size;
+	}
+	spin_unlock(&io_range_lock);
+#endif
+
+	return address;
+}
+
+unsigned long __weak pci_address_to_pio(phys_addr_t address)
+{
+#ifdef PCI_IOBASE
+	struct io_range *res;
+	resource_size_t offset = 0;
+	unsigned long addr = -1;
+
+	spin_lock(&io_range_lock);
+	list_for_each_entry(res, &io_range_list, list) {
+		if (address >= res->start && address < res->start + res->size) {
+			addr = address - res->start + offset;
+			break;
+		}
+		offset += res->size;
+	}
+	spin_unlock(&io_range_lock);
+
+	return addr;
+#else
+	if (address > IO_SPACE_LIMIT)
+		return (unsigned long)-1;
+
+	return (unsigned long) address;
+#endif
+}
+
+static int __of_address_to_resource(struct device_node *dev,
+		const __be32 *addrp, u64 size, unsigned int flags,
+		const char *name, struct resource *r)
+{
+	u64 taddr;
+
+	if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
+		return -EINVAL;
+	taddr = of_translate_address(dev, addrp);
+	if (taddr == OF_BAD_ADDR)
+		return -EINVAL;
+	memset(r, 0, sizeof(struct resource));
+	if (flags & IORESOURCE_IO) {
+		unsigned long port;
+		port = pci_address_to_pio(taddr);
+		if (port == (unsigned long)-1)
+			return -EINVAL;
+		r->start = port;
+		r->end = port + size - 1;
+	} else {
+		r->start = taddr;
+		r->end = taddr + size - 1;
+	}
+	r->flags = flags;
+	r->name = name ? name : dev->full_name;
+
+	return 0;
+}
+
+/**
+ * of_address_to_resource - Translate device tree address and return as resource
+ *
+ * Note that if your address is a PIO address, the conversion will fail if
+ * the physical address can't be internally converted to an IO token with
+ * pci_address_to_pio(), that is because it's either called to early or it
+ * can't be matched to any host bridge IO space
+ */
+int of_address_to_resource(struct device_node *dev, int index,
+			   struct resource *r)
+{
+	const __be32	*addrp;
+	u64		size;
+	unsigned int	flags;
+	const char	*name = NULL;
+
+	addrp = of_get_address(dev, index, &size, &flags);
+	if (addrp == NULL)
+		return -EINVAL;
+
+	/* Get optional "reg-names" property to add a name to a resource */
+	of_property_read_string_index(dev, "reg-names",	index, &name);
+
+	return __of_address_to_resource(dev, addrp, size, flags, name, r);
+}
+EXPORT_SYMBOL_GPL(of_address_to_resource);
+
+struct device_node *of_find_matching_node_by_address(struct device_node *from,
+					const struct of_device_id *matches,
+					u64 base_address)
+{
+	struct device_node *dn = of_find_matching_node(from, matches);
+	struct resource res;
+
+	while (dn) {
+		if (of_address_to_resource(dn, 0, &res))
+			continue;
+		if (res.start == base_address)
+			return dn;
+		dn = of_find_matching_node(dn, matches);
+	}
+
+	return NULL;
+}
+
+
+/**
+ * of_iomap - Maps the memory mapped IO for a given device_node
+ * @device:	the device whose io range will be mapped
+ * @index:	index of the io range
+ *
+ * Returns a pointer to the mapped memory
+ */
+void __iomem *of_iomap(struct device_node *np, int index)
+{
+	struct resource res;
+
+	if (of_address_to_resource(np, index, &res))
+		return NULL;
+
+	return ioremap(res.start, resource_size(&res));
+}
+EXPORT_SYMBOL(of_iomap);
+
+/*
+ * of_io_request_and_map - Requests a resource and maps the memory mapped IO
+ *			   for a given device_node
+ * @device:	the device whose io range will be mapped
+ * @index:	index of the io range
+ * @name:	name of the resource
+ *
+ * Returns a pointer to the requested and mapped memory or an ERR_PTR() encoded
+ * error code on failure. Usage example:
+ *
+ *	base = of_io_request_and_map(node, 0, "foo");
+ *	if (IS_ERR(base))
+ *		return PTR_ERR(base);
+ */
+void __iomem *of_io_request_and_map(struct device_node *np, int index,
+					const char *name)
+{
+	struct resource res;
+	void __iomem *mem;
+
+	if (of_address_to_resource(np, index, &res))
+		return IOMEM_ERR_PTR(-EINVAL);
+
+	if (!request_mem_region(res.start, resource_size(&res), name))
+		return IOMEM_ERR_PTR(-EBUSY);
+
+	mem = ioremap(res.start, resource_size(&res));
+	if (!mem) {
+		release_mem_region(res.start, resource_size(&res));
+		return IOMEM_ERR_PTR(-ENOMEM);
+	}
+
+	return mem;
+}
+EXPORT_SYMBOL(of_io_request_and_map);
+
+/**
+ * of_dma_get_range - Get DMA range info
+ * @np:		device node to get DMA range info
+ * @dma_addr:	pointer to store initial DMA address of DMA range
+ * @paddr:	pointer to store initial CPU address of DMA range
+ * @size:	pointer to store size of DMA range
+ *
+ * Look in bottom up direction for the first "dma-ranges" property
+ * and parse it.
+ *  dma-ranges format:
+ *	DMA addr (dma_addr)	: naddr cells
+ *	CPU addr (phys_addr_t)	: pna cells
+ *	size			: nsize cells
+ *
+ * It returns -ENODEV if "dma-ranges" property was not found
+ * for this device in DT.
+ */
+int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *size)
+{
+	struct device_node *node = of_node_get(np);
+	const __be32 *ranges = NULL;
+	int len, naddr, nsize, pna;
+	int ret = 0;
+	u64 dmaaddr;
+
+	if (!node)
+		return -EINVAL;
+
+	while (1) {
+		naddr = of_n_addr_cells(node);
+		nsize = of_n_size_cells(node);
+		node = of_get_next_parent(node);
+		if (!node)
+			break;
+
+		ranges = of_get_property(node, "dma-ranges", &len);
+
+		/* Ignore empty ranges, they imply no translation required */
+		if (ranges && len > 0)
+			break;
+
+		/*
+		 * At least empty ranges has to be defined for parent node if
+		 * DMA is supported
+		 */
+		if (!ranges)
+			break;
+	}
+
+	if (!ranges) {
+		pr_debug("%s: no dma-ranges found for node(%s)\n",
+			 __func__, np->full_name);
+		ret = -ENODEV;
+		goto out;
+	}
+
+	len /= sizeof(u32);
+
+	pna = of_n_addr_cells(node);
+
+	/* dma-ranges format:
+	 * DMA addr	: naddr cells
+	 * CPU addr	: pna cells
+	 * size		: nsize cells
+	 */
+	dmaaddr = of_read_number(ranges, naddr);
+	*paddr = of_translate_dma_address(np, ranges);
+	if (*paddr == OF_BAD_ADDR) {
+		pr_err("%s: translation of DMA address(%pad) to CPU address failed node(%s)\n",
+		       __func__, dma_addr, np->full_name);
+		ret = -EINVAL;
+		goto out;
+	}
+	*dma_addr = dmaaddr;
+
+	*size = of_read_number(ranges + naddr + pna, nsize);
+
+	pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
+		 *dma_addr, *paddr, *size);
+
+out:
+	of_node_put(node);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(of_dma_get_range);
+
+/**
+ * of_dma_is_coherent - Check if device is coherent
+ * @np:	device node
+ *
+ * It returns true if "dma-coherent" property was found
+ * for this device in DT.
+ */
+bool of_dma_is_coherent(struct device_node *np)
+{
+	struct device_node *node = of_node_get(np);
+
+	while (node) {
+		if (of_property_read_bool(node, "dma-coherent")) {
+			of_node_put(node);
+			return true;
+		}
+		node = of_get_next_parent(node);
+	}
+	of_node_put(node);
+	return false;
+}
+EXPORT_SYMBOL_GPL(of_dma_is_coherent);
diff --git a/kernel/drivers/of/base.c b/kernel/drivers/of/base.c
new file mode 100644
index 000000000..f0650265f
--- /dev/null
+++ b/kernel/drivers/of/base.c
@@ -0,0 +1,2276 @@
+/*
+ * Procedures for creating, accessing and interpreting the device tree.
+ *
+ * Paul Mackerras	August 1996.
+ * Copyright (C) 1996-2005 Paul Mackerras.
+ *
+ *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
+ *    {engebret|bergner}@us.ibm.com
+ *
+ *  Adapted for sparc and sparc64 by David S. Miller davem@davemloft.net
+ *
+ *  Reconsolidated from arch/x/kernel/prom.c by Stephen Rothwell and
+ *  Grant Likely.
+ *
+ *      This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+#include <linux/console.h>
+#include <linux/ctype.h>
+#include <linux/cpu.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_graph.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/proc_fs.h>
+
+#include "of_private.h"
+
+LIST_HEAD(aliases_lookup);
+
+struct device_node *of_root;
+EXPORT_SYMBOL(of_root);
+struct device_node *of_chosen;
+struct device_node *of_aliases;
+struct device_node *of_stdout;
+static const char *of_stdout_options;
+
+struct kset *of_kset;
+
+/*
+ * Used to protect the of_aliases, to hold off addition of nodes to sysfs.
+ * This mutex must be held whenever modifications are being made to the
+ * device tree. The of_{attach,detach}_node() and
+ * of_{add,remove,update}_property() helpers make sure this happens.
+ */
+DEFINE_MUTEX(of_mutex);
+
+/* use when traversing tree through the child, sibling,
+ * or parent members of struct device_node.
+ */
+DEFINE_RAW_SPINLOCK(devtree_lock);
+
+int of_n_addr_cells(struct device_node *np)
+{
+	const __be32 *ip;
+
+	do {
+		if (np->parent)
+			np = np->parent;
+		ip = of_get_property(np, "#address-cells", NULL);
+		if (ip)
+			return be32_to_cpup(ip);
+	} while (np->parent);
+	/* No #address-cells property for the root node */
+	return OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
+}
+EXPORT_SYMBOL(of_n_addr_cells);
+
+int of_n_size_cells(struct device_node *np)
+{
+	const __be32 *ip;
+
+	do {
+		if (np->parent)
+			np = np->parent;
+		ip = of_get_property(np, "#size-cells", NULL);
+		if (ip)
+			return be32_to_cpup(ip);
+	} while (np->parent);
+	/* No #size-cells property for the root node */
+	return OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
+}
+EXPORT_SYMBOL(of_n_size_cells);
+
+#ifdef CONFIG_NUMA
+int __weak of_node_to_nid(struct device_node *np)
+{
+	return numa_node_id();
+}
+#endif
+
+#ifndef CONFIG_OF_DYNAMIC
+static void of_node_release(struct kobject *kobj)
+{
+	/* Without CONFIG_OF_DYNAMIC, no nodes gets freed */
+}
+#endif /* CONFIG_OF_DYNAMIC */
+
+struct kobj_type of_node_ktype = {
+	.release = of_node_release,
+};
+
+static ssize_t of_node_property_read(struct file *filp, struct kobject *kobj,
+				struct bin_attribute *bin_attr, char *buf,
+				loff_t offset, size_t count)
+{
+	struct property *pp = container_of(bin_attr, struct property, attr);
+	return memory_read_from_buffer(buf, count, &offset, pp->value, pp->length);
+}
+
+static const char *safe_name(struct kobject *kobj, const char *orig_name)
+{
+	const char *name = orig_name;
+	struct kernfs_node *kn;
+	int i = 0;
+
+	/* don't be a hero. After 16 tries give up */
+	while (i < 16 && (kn = sysfs_get_dirent(kobj->sd, name))) {
+		sysfs_put(kn);
+		if (name != orig_name)
+			kfree(name);
+		name = kasprintf(GFP_KERNEL, "%s#%i", orig_name, ++i);
+	}
+
+	if (name != orig_name)
+		pr_warn("device-tree: Duplicate name in %s, renamed to \"%s\"\n",
+			kobject_name(kobj), name);
+	return name;
+}
+
+int __of_add_property_sysfs(struct device_node *np, struct property *pp)
+{
+	int rc;
+
+	/* Important: Don't leak passwords */
+	bool secure = strncmp(pp->name, "security-", 9) == 0;
+
+	if (!IS_ENABLED(CONFIG_SYSFS))
+		return 0;
+
+	if (!of_kset || !of_node_is_attached(np))
+		return 0;
+
+	sysfs_bin_attr_init(&pp->attr);
+	pp->attr.attr.name = safe_name(&np->kobj, pp->name);
+	pp->attr.attr.mode = secure ? S_IRUSR : S_IRUGO;
+	pp->attr.size = secure ? 0 : pp->length;
+	pp->attr.read = of_node_property_read;
+
+	rc = sysfs_create_bin_file(&np->kobj, &pp->attr);
+	WARN(rc, "error adding attribute %s to node %s\n", pp->name, np->full_name);
+	return rc;
+}
+
+int __of_attach_node_sysfs(struct device_node *np)
+{
+	const char *name;
+	struct property *pp;
+	int rc;
+
+	if (!IS_ENABLED(CONFIG_SYSFS))
+		return 0;
+
+	if (!of_kset)
+		return 0;
+
+	np->kobj.kset = of_kset;
+	if (!np->parent) {
+		/* Nodes without parents are new top level trees */
+		rc = kobject_add(&np->kobj, NULL, "%s",
+				 safe_name(&of_kset->kobj, "base"));
+	} else {
+		name = safe_name(&np->parent->kobj, kbasename(np->full_name));
+		if (!name || !name[0])
+			return -EINVAL;
+
+		rc = kobject_add(&np->kobj, &np->parent->kobj, "%s", name);
+	}
+	if (rc)
+		return rc;
+
+	for_each_property_of_node(np, pp)
+		__of_add_property_sysfs(np, pp);
+
+	return 0;
+}
+
+void __init of_core_init(void)
+{
+	struct device_node *np;
+
+	/* Create the kset, and register existing nodes */
+	mutex_lock(&of_mutex);
+	of_kset = kset_create_and_add("devicetree", NULL, firmware_kobj);
+	if (!of_kset) {
+		mutex_unlock(&of_mutex);
+		pr_err("devicetree: failed to register existing nodes\n");
+		return;
+	}
+	for_each_of_allnodes(np)
+		__of_attach_node_sysfs(np);
+	mutex_unlock(&of_mutex);
+
+	/* Symlink in /proc as required by userspace ABI */
+	if (of_root)
+		proc_symlink("device-tree", NULL, "/sys/firmware/devicetree/base");
+}
+
+static struct property *__of_find_property(const struct device_node *np,
+					   const char *name, int *lenp)
+{
+	struct property *pp;
+
+	if (!np)
+		return NULL;
+
+	for (pp = np->properties; pp; pp = pp->next) {
+		if (of_prop_cmp(pp->name, name) == 0) {
+			if (lenp)
+				*lenp = pp->length;
+			break;
+		}
+	}
+
+	return pp;
+}
+
+struct property *of_find_property(const struct device_node *np,
+				  const char *name,
+				  int *lenp)
+{
+	struct property *pp;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	pp = __of_find_property(np, name, lenp);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+	return pp;
+}
+EXPORT_SYMBOL(of_find_property);
+
+struct device_node *__of_find_all_nodes(struct device_node *prev)
+{
+	struct device_node *np;
+	if (!prev) {
+		np = of_root;
+	} else if (prev->child) {
+		np = prev->child;
+	} else {
+		/* Walk back up looking for a sibling, or the end of the structure */
+		np = prev;
+		while (np->parent && !np->sibling)
+			np = np->parent;
+		np = np->sibling; /* Might be null at the end of the tree */
+	}
+	return np;
+}
+
+/**
+ * of_find_all_nodes - Get next node in global list
+ * @prev:	Previous node or NULL to start iteration
+ *		of_node_put() will be called on it
+ *
+ * Returns a node pointer with refcount incremented, use
+ * of_node_put() on it when done.
+ */
+struct device_node *of_find_all_nodes(struct device_node *prev)
+{
+	struct device_node *np;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	np = __of_find_all_nodes(prev);
+	of_node_get(np);
+	of_node_put(prev);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	return np;
+}
+EXPORT_SYMBOL(of_find_all_nodes);
+
+/*
+ * Find a property with a given name for a given node
+ * and return the value.
+ */
+const void *__of_get_property(const struct device_node *np,
+			      const char *name, int *lenp)
+{
+	struct property *pp = __of_find_property(np, name, lenp);
+
+	return pp ? pp->value : NULL;
+}
+
+/*
+ * Find a property with a given name for a given node
+ * and return the value.
+ */
+const void *of_get_property(const struct device_node *np, const char *name,
+			    int *lenp)
+{
+	struct property *pp = of_find_property(np, name, lenp);
+
+	return pp ? pp->value : NULL;
+}
+EXPORT_SYMBOL(of_get_property);
+
+/*
+ * arch_match_cpu_phys_id - Match the given logical CPU and physical id
+ *
+ * @cpu: logical cpu index of a core/thread
+ * @phys_id: physical identifier of a core/thread
+ *
+ * CPU logical to physical index mapping is architecture specific.
+ * However this __weak function provides a default match of physical
+ * id to logical cpu index. phys_id provided here is usually values read
+ * from the device tree which must match the hardware internal registers.
+ *
+ * Returns true if the physical identifier and the logical cpu index
+ * correspond to the same core/thread, false otherwise.
+ */
+bool __weak arch_match_cpu_phys_id(int cpu, u64 phys_id)
+{
+	return (u32)phys_id == cpu;
+}
+
+/**
+ * Checks if the given "prop_name" property holds the physical id of the
+ * core/thread corresponding to the logical cpu 'cpu'. If 'thread' is not
+ * NULL, local thread number within the core is returned in it.
+ */
+static bool __of_find_n_match_cpu_property(struct device_node *cpun,
+			const char *prop_name, int cpu, unsigned int *thread)
+{
+	const __be32 *cell;
+	int ac, prop_len, tid;
+	u64 hwid;
+
+	ac = of_n_addr_cells(cpun);
+	cell = of_get_property(cpun, prop_name, &prop_len);
+	if (!cell || !ac)
+		return false;
+	prop_len /= sizeof(*cell) * ac;
+	for (tid = 0; tid < prop_len; tid++) {
+		hwid = of_read_number(cell, ac);
+		if (arch_match_cpu_phys_id(cpu, hwid)) {
+			if (thread)
+				*thread = tid;
+			return true;
+		}
+		cell += ac;
+	}
+	return false;
+}
+
+/*
+ * arch_find_n_match_cpu_physical_id - See if the given device node is
+ * for the cpu corresponding to logical cpu 'cpu'.  Return true if so,
+ * else false.  If 'thread' is non-NULL, the local thread number within the
+ * core is returned in it.
+ */
+bool __weak arch_find_n_match_cpu_physical_id(struct device_node *cpun,
+					      int cpu, unsigned int *thread)
+{
+	/* Check for non-standard "ibm,ppc-interrupt-server#s" property
+	 * for thread ids on PowerPC. If it doesn't exist fallback to
+	 * standard "reg" property.
+	 */
+	if (IS_ENABLED(CONFIG_PPC) &&
+	    __of_find_n_match_cpu_property(cpun,
+					   "ibm,ppc-interrupt-server#s",
+					   cpu, thread))
+		return true;
+
+	if (__of_find_n_match_cpu_property(cpun, "reg", cpu, thread))
+		return true;
+
+	return false;
+}
+
+/**
+ * of_get_cpu_node - Get device node associated with the given logical CPU
+ *
+ * @cpu: CPU number(logical index) for which device node is required
+ * @thread: if not NULL, local thread number within the physical core is
+ *          returned
+ *
+ * The main purpose of this function is to retrieve the device node for the
+ * given logical CPU index. It should be used to initialize the of_node in
+ * cpu device. Once of_node in cpu device is populated, all the further
+ * references can use that instead.
+ *
+ * CPU logical to physical index mapping is architecture specific and is built
+ * before booting secondary cores. This function uses arch_match_cpu_phys_id
+ * which can be overridden by architecture specific implementation.
+ *
+ * Returns a node pointer for the logical cpu if found, else NULL.
+ */
+struct device_node *of_get_cpu_node(int cpu, unsigned int *thread)
+{
+	struct device_node *cpun;
+
+	for_each_node_by_type(cpun, "cpu") {
+		if (arch_find_n_match_cpu_physical_id(cpun, cpu, thread))
+			return cpun;
+	}
+	return NULL;
+}
+EXPORT_SYMBOL(of_get_cpu_node);
+
+/**
+ * __of_device_is_compatible() - Check if the node matches given constraints
+ * @device: pointer to node
+ * @compat: required compatible string, NULL or "" for any match
+ * @type: required device_type value, NULL or "" for any match
+ * @name: required node name, NULL or "" for any match
+ *
+ * Checks if the given @compat, @type and @name strings match the
+ * properties of the given @device. A constraints can be skipped by
+ * passing NULL or an empty string as the constraint.
+ *
+ * Returns 0 for no match, and a positive integer on match. The return
+ * value is a relative score with larger values indicating better
+ * matches. The score is weighted for the most specific compatible value
+ * to get the highest score. Matching type is next, followed by matching
+ * name. Practically speaking, this results in the following priority
+ * order for matches:
+ *
+ * 1. specific compatible && type && name
+ * 2. specific compatible && type
+ * 3. specific compatible && name
+ * 4. specific compatible
+ * 5. general compatible && type && name
+ * 6. general compatible && type
+ * 7. general compatible && name
+ * 8. general compatible
+ * 9. type && name
+ * 10. type
+ * 11. name
+ */
+static int __of_device_is_compatible(const struct device_node *device,
+				     const char *compat, const char *type, const char *name)
+{
+	struct property *prop;
+	const char *cp;
+	int index = 0, score = 0;
+
+	/* Compatible match has highest priority */
+	if (compat && compat[0]) {
+		prop = __of_find_property(device, "compatible", NULL);
+		for (cp = of_prop_next_string(prop, NULL); cp;
+		     cp = of_prop_next_string(prop, cp), index++) {
+			if (of_compat_cmp(cp, compat, strlen(compat)) == 0) {
+				score = INT_MAX/2 - (index << 2);
+				break;
+			}
+		}
+		if (!score)
+			return 0;
+	}
+
+	/* Matching type is better than matching name */
+	if (type && type[0]) {
+		if (!device->type || of_node_cmp(type, device->type))
+			return 0;
+		score += 2;
+	}
+
+	/* Matching name is a bit better than not */
+	if (name && name[0]) {
+		if (!device->name || of_node_cmp(name, device->name))
+			return 0;
+		score++;
+	}
+
+	return score;
+}
+
+/** Checks if the given "compat" string matches one of the strings in
+ * the device's "compatible" property
+ */
+int of_device_is_compatible(const struct device_node *device,
+		const char *compat)
+{
+	unsigned long flags;
+	int res;
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	res = __of_device_is_compatible(device, compat, NULL, NULL);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	return res;
+}
+EXPORT_SYMBOL(of_device_is_compatible);
+
+/**
+ * of_machine_is_compatible - Test root of device tree for a given compatible value
+ * @compat: compatible string to look for in root node's compatible property.
+ *
+ * Returns a positive integer if the root node has the given value in its
+ * compatible property.
+ */
+int of_machine_is_compatible(const char *compat)
+{
+	struct device_node *root;
+	int rc = 0;
+
+	root = of_find_node_by_path("/");
+	if (root) {
+		rc = of_device_is_compatible(root, compat);
+		of_node_put(root);
+	}
+	return rc;
+}
+EXPORT_SYMBOL(of_machine_is_compatible);
+
+/**
+ *  __of_device_is_available - check if a device is available for use
+ *
+ *  @device: Node to check for availability, with locks already held
+ *
+ *  Returns true if the status property is absent or set to "okay" or "ok",
+ *  false otherwise
+ */
+static bool __of_device_is_available(const struct device_node *device)
+{
+	const char *status;
+	int statlen;
+
+	if (!device)
+		return false;
+
+	status = __of_get_property(device, "status", &statlen);
+	if (status == NULL)
+		return true;
+
+	if (statlen > 0) {
+		if (!strcmp(status, "okay") || !strcmp(status, "ok"))
+			return true;
+	}
+
+	return false;
+}
+
+/**
+ *  of_device_is_available - check if a device is available for use
+ *
+ *  @device: Node to check for availability
+ *
+ *  Returns true if the status property is absent or set to "okay" or "ok",
+ *  false otherwise
+ */
+bool of_device_is_available(const struct device_node *device)
+{
+	unsigned long flags;
+	bool res;
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	res = __of_device_is_available(device);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	return res;
+
+}
+EXPORT_SYMBOL(of_device_is_available);
+
+/**
+ *  of_device_is_big_endian - check if a device has BE registers
+ *
+ *  @device: Node to check for endianness
+ *
+ *  Returns true if the device has a "big-endian" property, or if the kernel
+ *  was compiled for BE *and* the device has a "native-endian" property.
+ *  Returns false otherwise.
+ *
+ *  Callers would nominally use ioread32be/iowrite32be if
+ *  of_device_is_big_endian() == true, or readl/writel otherwise.
+ */
+bool of_device_is_big_endian(const struct device_node *device)
+{
+	if (of_property_read_bool(device, "big-endian"))
+		return true;
+	if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) &&
+	    of_property_read_bool(device, "native-endian"))
+		return true;
+	return false;
+}
+EXPORT_SYMBOL(of_device_is_big_endian);
+
+/**
+ *	of_get_parent - Get a node's parent if any
+ *	@node:	Node to get parent
+ *
+ *	Returns a node pointer with refcount incremented, use
+ *	of_node_put() on it when done.
+ */
+struct device_node *of_get_parent(const struct device_node *node)
+{
+	struct device_node *np;
+	unsigned long flags;
+
+	if (!node)
+		return NULL;
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	np = of_node_get(node->parent);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	return np;
+}
+EXPORT_SYMBOL(of_get_parent);
+
+/**
+ *	of_get_next_parent - Iterate to a node's parent
+ *	@node:	Node to get parent of
+ *
+ *	This is like of_get_parent() except that it drops the
+ *	refcount on the passed node, making it suitable for iterating
+ *	through a node's parents.
+ *
+ *	Returns a node pointer with refcount incremented, use
+ *	of_node_put() on it when done.
+ */
+struct device_node *of_get_next_parent(struct device_node *node)
+{
+	struct device_node *parent;
+	unsigned long flags;
+
+	if (!node)
+		return NULL;
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	parent = of_node_get(node->parent);
+	of_node_put(node);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	return parent;
+}
+EXPORT_SYMBOL(of_get_next_parent);
+
+static struct device_node *__of_get_next_child(const struct device_node *node,
+						struct device_node *prev)
+{
+	struct device_node *next;
+
+	if (!node)
+		return NULL;
+
+	next = prev ? prev->sibling : node->child;
+	for (; next; next = next->sibling)
+		if (of_node_get(next))
+			break;
+	of_node_put(prev);
+	return next;
+}
+#define __for_each_child_of_node(parent, child) \
+	for (child = __of_get_next_child(parent, NULL); child != NULL; \
+	     child = __of_get_next_child(parent, child))
+
+/**
+ *	of_get_next_child - Iterate a node childs
+ *	@node:	parent node
+ *	@prev:	previous child of the parent node, or NULL to get first
+ *
+ *	Returns a node pointer with refcount incremented, use of_node_put() on
+ *	it when done. Returns NULL when prev is the last child. Decrements the
+ *	refcount of prev.
+ */
+struct device_node *of_get_next_child(const struct device_node *node,
+	struct device_node *prev)
+{
+	struct device_node *next;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	next = __of_get_next_child(node, prev);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	return next;
+}
+EXPORT_SYMBOL(of_get_next_child);
+
+/**
+ *	of_get_next_available_child - Find the next available child node
+ *	@node:	parent node
+ *	@prev:	previous child of the parent node, or NULL to get first
+ *
+ *      This function is like of_get_next_child(), except that it
+ *      automatically skips any disabled nodes (i.e. status = "disabled").
+ */
+struct device_node *of_get_next_available_child(const struct device_node *node,
+	struct device_node *prev)
+{
+	struct device_node *next;
+	unsigned long flags;
+
+	if (!node)
+		return NULL;
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	next = prev ? prev->sibling : node->child;
+	for (; next; next = next->sibling) {
+		if (!__of_device_is_available(next))
+			continue;
+		if (of_node_get(next))
+			break;
+	}
+	of_node_put(prev);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	return next;
+}
+EXPORT_SYMBOL(of_get_next_available_child);
+
+/**
+ *	of_get_child_by_name - Find the child node by name for a given parent
+ *	@node:	parent node
+ *	@name:	child name to look for.
+ *
+ *      This function looks for child node for given matching name
+ *
+ *	Returns a node pointer if found, with refcount incremented, use
+ *	of_node_put() on it when done.
+ *	Returns NULL if node is not found.
+ */
+struct device_node *of_get_child_by_name(const struct device_node *node,
+				const char *name)
+{
+	struct device_node *child;
+
+	for_each_child_of_node(node, child)
+		if (child->name && (of_node_cmp(child->name, name) == 0))
+			break;
+	return child;
+}
+EXPORT_SYMBOL(of_get_child_by_name);
+
+static struct device_node *__of_find_node_by_path(struct device_node *parent,
+						const char *path)
+{
+	struct device_node *child;
+	int len;
+
+	len = strcspn(path, "/:");
+	if (!len)
+		return NULL;
+
+	__for_each_child_of_node(parent, child) {
+		const char *name = strrchr(child->full_name, '/');
+		if (WARN(!name, "malformed device_node %s\n", child->full_name))
+			continue;
+		name++;
+		if (strncmp(path, name, len) == 0 && (strlen(name) == len))
+			return child;
+	}
+	return NULL;
+}
+
+/**
+ *	of_find_node_opts_by_path - Find a node matching a full OF path
+ *	@path: Either the full path to match, or if the path does not
+ *	       start with '/', the name of a property of the /aliases
+ *	       node (an alias).  In the case of an alias, the node
+ *	       matching the alias' value will be returned.
+ *	@opts: Address of a pointer into which to store the start of
+ *	       an options string appended to the end of the path with
+ *	       a ':' separator.
+ *
+ *	Valid paths:
+ *		/foo/bar	Full path
+ *		foo		Valid alias
+ *		foo/bar		Valid alias + relative path
+ *
+ *	Returns a node pointer with refcount incremented, use
+ *	of_node_put() on it when done.
+ */
+struct device_node *of_find_node_opts_by_path(const char *path, const char **opts)
+{
+	struct device_node *np = NULL;
+	struct property *pp;
+	unsigned long flags;
+	const char *separator = strchr(path, ':');
+
+	if (opts)
+		*opts = separator ? separator + 1 : NULL;
+
+	if (strcmp(path, "/") == 0)
+		return of_node_get(of_root);
+
+	/* The path could begin with an alias */
+	if (*path != '/') {
+		int len;
+		const char *p = separator;
+
+		if (!p)
+			p = strchrnul(path, '/');
+		len = p - path;
+
+		/* of_aliases must not be NULL */
+		if (!of_aliases)
+			return NULL;
+
+		for_each_property_of_node(of_aliases, pp) {
+			if (strlen(pp->name) == len && !strncmp(pp->name, path, len)) {
+				np = of_find_node_by_path(pp->value);
+				break;
+			}
+		}
+		if (!np)
+			return NULL;
+		path = p;
+	}
+
+	/* Step down the tree matching path components */
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	if (!np)
+		np = of_node_get(of_root);
+	while (np && *path == '/') {
+		path++; /* Increment past '/' delimiter */
+		np = __of_find_node_by_path(np, path);
+		path = strchrnul(path, '/');
+		if (separator && separator < path)
+			break;
+	}
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	return np;
+}
+EXPORT_SYMBOL(of_find_node_opts_by_path);
+
+/**
+ *	of_find_node_by_name - Find a node by its "name" property
+ *	@from:	The node to start searching from or NULL, the node
+ *		you pass will not be searched, only the next one
+ *		will; typically, you pass what the previous call
+ *		returned. of_node_put() will be called on it
+ *	@name:	The name string to match against
+ *
+ *	Returns a node pointer with refcount incremented, use
+ *	of_node_put() on it when done.
+ */
+struct device_node *of_find_node_by_name(struct device_node *from,
+	const char *name)
+{
+	struct device_node *np;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	for_each_of_allnodes_from(from, np)
+		if (np->name && (of_node_cmp(np->name, name) == 0)
+		    && of_node_get(np))
+			break;
+	of_node_put(from);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	return np;
+}
+EXPORT_SYMBOL(of_find_node_by_name);
+
+/**
+ *	of_find_node_by_type - Find a node by its "device_type" property
+ *	@from:	The node to start searching from, or NULL to start searching
+ *		the entire device tree. The node you pass will not be
+ *		searched, only the next one will; typically, you pass
+ *		what the previous call returned. of_node_put() will be
+ *		called on from for you.
+ *	@type:	The type string to match against
+ *
+ *	Returns a node pointer with refcount incremented, use
+ *	of_node_put() on it when done.
+ */
+struct device_node *of_find_node_by_type(struct device_node *from,
+	const char *type)
+{
+	struct device_node *np;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	for_each_of_allnodes_from(from, np)
+		if (np->type && (of_node_cmp(np->type, type) == 0)
+		    && of_node_get(np))
+			break;
+	of_node_put(from);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	return np;
+}
+EXPORT_SYMBOL(of_find_node_by_type);
+
+/**
+ *	of_find_compatible_node - Find a node based on type and one of the
+ *                                tokens in its "compatible" property
+ *	@from:		The node to start searching from or NULL, the node
+ *			you pass will not be searched, only the next one
+ *			will; typically, you pass what the previous call
+ *			returned. of_node_put() will be called on it
+ *	@type:		The type string to match "device_type" or NULL to ignore
+ *	@compatible:	The string to match to one of the tokens in the device
+ *			"compatible" list.
+ *
+ *	Returns a node pointer with refcount incremented, use
+ *	of_node_put() on it when done.
+ */
+struct device_node *of_find_compatible_node(struct device_node *from,
+	const char *type, const char *compatible)
+{
+	struct device_node *np;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	for_each_of_allnodes_from(from, np)
+		if (__of_device_is_compatible(np, compatible, type, NULL) &&
+		    of_node_get(np))
+			break;
+	of_node_put(from);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	return np;
+}
+EXPORT_SYMBOL(of_find_compatible_node);
+
+/**
+ *	of_find_node_with_property - Find a node which has a property with
+ *                                   the given name.
+ *	@from:		The node to start searching from or NULL, the node
+ *			you pass will not be searched, only the next one
+ *			will; typically, you pass what the previous call
+ *			returned. of_node_put() will be called on it
+ *	@prop_name:	The name of the property to look for.
+ *
+ *	Returns a node pointer with refcount incremented, use
+ *	of_node_put() on it when done.
+ */
+struct device_node *of_find_node_with_property(struct device_node *from,
+	const char *prop_name)
+{
+	struct device_node *np;
+	struct property *pp;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	for_each_of_allnodes_from(from, np) {
+		for (pp = np->properties; pp; pp = pp->next) {
+			if (of_prop_cmp(pp->name, prop_name) == 0) {
+				of_node_get(np);
+				goto out;
+			}
+		}
+	}
+out:
+	of_node_put(from);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	return np;
+}
+EXPORT_SYMBOL(of_find_node_with_property);
+
+static
+const struct of_device_id *__of_match_node(const struct of_device_id *matches,
+					   const struct device_node *node)
+{
+	const struct of_device_id *best_match = NULL;
+	int score, best_score = 0;
+
+	if (!matches)
+		return NULL;
+
+	for (; matches->name[0] || matches->type[0] || matches->compatible[0]; matches++) {
+		score = __of_device_is_compatible(node, matches->compatible,
+						  matches->type, matches->name);
+		if (score > best_score) {
+			best_match = matches;
+			best_score = score;
+		}
+	}
+
+	return best_match;
+}
+
+/**
+ * of_match_node - Tell if a device_node has a matching of_match structure
+ *	@matches:	array of of device match structures to search in
+ *	@node:		the of device structure to match against
+ *
+ *	Low level utility function used by device matching.
+ */
+const struct of_device_id *of_match_node(const struct of_device_id *matches,
+					 const struct device_node *node)
+{
+	const struct of_device_id *match;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	match = __of_match_node(matches, node);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	return match;
+}
+EXPORT_SYMBOL(of_match_node);
+
+/**
+ *	of_find_matching_node_and_match - Find a node based on an of_device_id
+ *					  match table.
+ *	@from:		The node to start searching from or NULL, the node
+ *			you pass will not be searched, only the next one
+ *			will; typically, you pass what the previous call
+ *			returned. of_node_put() will be called on it
+ *	@matches:	array of of device match structures to search in
+ *	@match		Updated to point at the matches entry which matched
+ *
+ *	Returns a node pointer with refcount incremented, use
+ *	of_node_put() on it when done.
+ */
+struct device_node *of_find_matching_node_and_match(struct device_node *from,
+					const struct of_device_id *matches,
+					const struct of_device_id **match)
+{
+	struct device_node *np;
+	const struct of_device_id *m;
+	unsigned long flags;
+
+	if (match)
+		*match = NULL;
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	for_each_of_allnodes_from(from, np) {
+		m = __of_match_node(matches, np);
+		if (m && of_node_get(np)) {
+			if (match)
+				*match = m;
+			break;
+		}
+	}
+	of_node_put(from);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	return np;
+}
+EXPORT_SYMBOL(of_find_matching_node_and_match);
+
+/**
+ * of_modalias_node - Lookup appropriate modalias for a device node
+ * @node:	pointer to a device tree node
+ * @modalias:	Pointer to buffer that modalias value will be copied into
+ * @len:	Length of modalias value
+ *
+ * Based on the value of the compatible property, this routine will attempt
+ * to choose an appropriate modalias value for a particular device tree node.
+ * It does this by stripping the manufacturer prefix (as delimited by a ',')
+ * from the first entry in the compatible list property.
+ *
+ * This routine returns 0 on success, <0 on failure.
+ */
+int of_modalias_node(struct device_node *node, char *modalias, int len)
+{
+	const char *compatible, *p;
+	int cplen;
+
+	compatible = of_get_property(node, "compatible", &cplen);
+	if (!compatible || strlen(compatible) > cplen)
+		return -ENODEV;
+	p = strchr(compatible, ',');
+	strlcpy(modalias, p ? p + 1 : compatible, len);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_modalias_node);
+
+/**
+ * of_find_node_by_phandle - Find a node given a phandle
+ * @handle:	phandle of the node to find
+ *
+ * Returns a node pointer with refcount incremented, use
+ * of_node_put() on it when done.
+ */
+struct device_node *of_find_node_by_phandle(phandle handle)
+{
+	struct device_node *np;
+	unsigned long flags;
+
+	if (!handle)
+		return NULL;
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	for_each_of_allnodes(np)
+		if (np->phandle == handle)
+			break;
+	of_node_get(np);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	return np;
+}
+EXPORT_SYMBOL(of_find_node_by_phandle);
+
+/**
+ * of_property_count_elems_of_size - Count the number of elements in a property
+ *
+ * @np:		device node from which the property value is to be read.
+ * @propname:	name of the property to be searched.
+ * @elem_size:	size of the individual element
+ *
+ * Search for a property in a device node and count the number of elements of
+ * size elem_size in it. Returns number of elements on sucess, -EINVAL if the
+ * property does not exist or its length does not match a multiple of elem_size
+ * and -ENODATA if the property does not have a value.
+ */
+int of_property_count_elems_of_size(const struct device_node *np,
+				const char *propname, int elem_size)
+{
+	struct property *prop = of_find_property(np, propname, NULL);
+
+	if (!prop)
+		return -EINVAL;
+	if (!prop->value)
+		return -ENODATA;
+
+	if (prop->length % elem_size != 0) {
+		pr_err("size of %s in node %s is not a multiple of %d\n",
+		       propname, np->full_name, elem_size);
+		return -EINVAL;
+	}
+
+	return prop->length / elem_size;
+}
+EXPORT_SYMBOL_GPL(of_property_count_elems_of_size);
+
+/**
+ * of_find_property_value_of_size
+ *
+ * @np:		device node from which the property value is to be read.
+ * @propname:	name of the property to be searched.
+ * @len:	requested length of property value
+ *
+ * Search for a property in a device node and valid the requested size.
+ * Returns the property value on success, -EINVAL if the property does not
+ *  exist, -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ */
+static void *of_find_property_value_of_size(const struct device_node *np,
+			const char *propname, u32 len)
+{
+	struct property *prop = of_find_property(np, propname, NULL);
+
+	if (!prop)
+		return ERR_PTR(-EINVAL);
+	if (!prop->value)
+		return ERR_PTR(-ENODATA);
+	if (len > prop->length)
+		return ERR_PTR(-EOVERFLOW);
+
+	return prop->value;
+}
+
+/**
+ * of_property_read_u32_index - Find and read a u32 from a multi-value property.
+ *
+ * @np:		device node from which the property value is to be read.
+ * @propname:	name of the property to be searched.
+ * @index:	index of the u32 in the list of values
+ * @out_value:	pointer to return value, modified only if no error.
+ *
+ * Search for a property in a device node and read nth 32-bit value from
+ * it. Returns 0 on success, -EINVAL if the property does not exist,
+ * -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ * The out_value is modified only if a valid u32 value can be decoded.
+ */
+int of_property_read_u32_index(const struct device_node *np,
+				       const char *propname,
+				       u32 index, u32 *out_value)
+{
+	const u32 *val = of_find_property_value_of_size(np, propname,
+					((index + 1) * sizeof(*out_value)));
+
+	if (IS_ERR(val))
+		return PTR_ERR(val);
+
+	*out_value = be32_to_cpup(((__be32 *)val) + index);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_property_read_u32_index);
+
+/**
+ * of_property_read_u8_array - Find and read an array of u8 from a property.
+ *
+ * @np:		device node from which the property value is to be read.
+ * @propname:	name of the property to be searched.
+ * @out_values:	pointer to return value, modified only if return value is 0.
+ * @sz:		number of array elements to read
+ *
+ * Search for a property in a device node and read 8-bit value(s) from
+ * it. Returns 0 on success, -EINVAL if the property does not exist,
+ * -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ * dts entry of array should be like:
+ *	property = /bits/ 8 <0x50 0x60 0x70>;
+ *
+ * The out_values is modified only if a valid u8 value can be decoded.
+ */
+int of_property_read_u8_array(const struct device_node *np,
+			const char *propname, u8 *out_values, size_t sz)
+{
+	const u8 *val = of_find_property_value_of_size(np, propname,
+						(sz * sizeof(*out_values)));
+
+	if (IS_ERR(val))
+		return PTR_ERR(val);
+
+	while (sz--)
+		*out_values++ = *val++;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_property_read_u8_array);
+
+/**
+ * of_property_read_u16_array - Find and read an array of u16 from a property.
+ *
+ * @np:		device node from which the property value is to be read.
+ * @propname:	name of the property to be searched.
+ * @out_values:	pointer to return value, modified only if return value is 0.
+ * @sz:		number of array elements to read
+ *
+ * Search for a property in a device node and read 16-bit value(s) from
+ * it. Returns 0 on success, -EINVAL if the property does not exist,
+ * -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ * dts entry of array should be like:
+ *	property = /bits/ 16 <0x5000 0x6000 0x7000>;
+ *
+ * The out_values is modified only if a valid u16 value can be decoded.
+ */
+int of_property_read_u16_array(const struct device_node *np,
+			const char *propname, u16 *out_values, size_t sz)
+{
+	const __be16 *val = of_find_property_value_of_size(np, propname,
+						(sz * sizeof(*out_values)));
+
+	if (IS_ERR(val))
+		return PTR_ERR(val);
+
+	while (sz--)
+		*out_values++ = be16_to_cpup(val++);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_property_read_u16_array);
+
+/**
+ * of_property_read_u32_array - Find and read an array of 32 bit integers
+ * from a property.
+ *
+ * @np:		device node from which the property value is to be read.
+ * @propname:	name of the property to be searched.
+ * @out_values:	pointer to return value, modified only if return value is 0.
+ * @sz:		number of array elements to read
+ *
+ * Search for a property in a device node and read 32-bit value(s) from
+ * it. Returns 0 on success, -EINVAL if the property does not exist,
+ * -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ * The out_values is modified only if a valid u32 value can be decoded.
+ */
+int of_property_read_u32_array(const struct device_node *np,
+			       const char *propname, u32 *out_values,
+			       size_t sz)
+{
+	const __be32 *val = of_find_property_value_of_size(np, propname,
+						(sz * sizeof(*out_values)));
+
+	if (IS_ERR(val))
+		return PTR_ERR(val);
+
+	while (sz--)
+		*out_values++ = be32_to_cpup(val++);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_property_read_u32_array);
+
+/**
+ * of_property_read_u64 - Find and read a 64 bit integer from a property
+ * @np:		device node from which the property value is to be read.
+ * @propname:	name of the property to be searched.
+ * @out_value:	pointer to return value, modified only if return value is 0.
+ *
+ * Search for a property in a device node and read a 64-bit value from
+ * it. Returns 0 on success, -EINVAL if the property does not exist,
+ * -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ * The out_value is modified only if a valid u64 value can be decoded.
+ */
+int of_property_read_u64(const struct device_node *np, const char *propname,
+			 u64 *out_value)
+{
+	const __be32 *val = of_find_property_value_of_size(np, propname,
+						sizeof(*out_value));
+
+	if (IS_ERR(val))
+		return PTR_ERR(val);
+
+	*out_value = of_read_number(val, 2);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_property_read_u64);
+
+/**
+ * of_property_read_u64_array - Find and read an array of 64 bit integers
+ * from a property.
+ *
+ * @np:		device node from which the property value is to be read.
+ * @propname:	name of the property to be searched.
+ * @out_values:	pointer to return value, modified only if return value is 0.
+ * @sz:		number of array elements to read
+ *
+ * Search for a property in a device node and read 64-bit value(s) from
+ * it. Returns 0 on success, -EINVAL if the property does not exist,
+ * -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ * The out_values is modified only if a valid u64 value can be decoded.
+ */
+int of_property_read_u64_array(const struct device_node *np,
+			       const char *propname, u64 *out_values,
+			       size_t sz)
+{
+	const __be32 *val = of_find_property_value_of_size(np, propname,
+						(sz * sizeof(*out_values)));
+
+	if (IS_ERR(val))
+		return PTR_ERR(val);
+
+	while (sz--) {
+		*out_values++ = of_read_number(val, 2);
+		val += 2;
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_property_read_u64_array);
+
+/**
+ * of_property_read_string - Find and read a string from a property
+ * @np:		device node from which the property value is to be read.
+ * @propname:	name of the property to be searched.
+ * @out_string:	pointer to null terminated return string, modified only if
+ *		return value is 0.
+ *
+ * Search for a property in a device tree node and retrieve a null
+ * terminated string value (pointer to data, not a copy). Returns 0 on
+ * success, -EINVAL if the property does not exist, -ENODATA if property
+ * does not have a value, and -EILSEQ if the string is not null-terminated
+ * within the length of the property data.
+ *
+ * The out_string pointer is modified only if a valid string can be decoded.
+ */
+int of_property_read_string(struct device_node *np, const char *propname,
+				const char **out_string)
+{
+	struct property *prop = of_find_property(np, propname, NULL);
+	if (!prop)
+		return -EINVAL;
+	if (!prop->value)
+		return -ENODATA;
+	if (strnlen(prop->value, prop->length) >= prop->length)
+		return -EILSEQ;
+	*out_string = prop->value;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_property_read_string);
+
+/**
+ * of_property_match_string() - Find string in a list and return index
+ * @np: pointer to node containing string list property
+ * @propname: string list property name
+ * @string: pointer to string to search for in string list
+ *
+ * This function searches a string list property and returns the index
+ * of a specific string value.
+ */
+int of_property_match_string(struct device_node *np, const char *propname,
+			     const char *string)
+{
+	struct property *prop = of_find_property(np, propname, NULL);
+	size_t l;
+	int i;
+	const char *p, *end;
+
+	if (!prop)
+		return -EINVAL;
+	if (!prop->value)
+		return -ENODATA;
+
+	p = prop->value;
+	end = p + prop->length;
+
+	for (i = 0; p < end; i++, p += l) {
+		l = strnlen(p, end - p) + 1;
+		if (p + l > end)
+			return -EILSEQ;
+		pr_debug("comparing %s with %s\n", string, p);
+		if (strcmp(string, p) == 0)
+			return i; /* Found it; return index */
+	}
+	return -ENODATA;
+}
+EXPORT_SYMBOL_GPL(of_property_match_string);
+
+/**
+ * of_property_read_string_helper() - Utility helper for parsing string properties
+ * @np:		device node from which the property value is to be read.
+ * @propname:	name of the property to be searched.
+ * @out_strs:	output array of string pointers.
+ * @sz:		number of array elements to read.
+ * @skip:	Number of strings to skip over at beginning of list.
+ *
+ * Don't call this function directly. It is a utility helper for the
+ * of_property_read_string*() family of functions.
+ */
+int of_property_read_string_helper(struct device_node *np, const char *propname,
+				   const char **out_strs, size_t sz, int skip)
+{
+	struct property *prop = of_find_property(np, propname, NULL);
+	int l = 0, i = 0;
+	const char *p, *end;
+
+	if (!prop)
+		return -EINVAL;
+	if (!prop->value)
+		return -ENODATA;
+	p = prop->value;
+	end = p + prop->length;
+
+	for (i = 0; p < end && (!out_strs || i < skip + sz); i++, p += l) {
+		l = strnlen(p, end - p) + 1;
+		if (p + l > end)
+			return -EILSEQ;
+		if (out_strs && i >= skip)
+			*out_strs++ = p;
+	}
+	i -= skip;
+	return i <= 0 ? -ENODATA : i;
+}
+EXPORT_SYMBOL_GPL(of_property_read_string_helper);
+
+void of_print_phandle_args(const char *msg, const struct of_phandle_args *args)
+{
+	int i;
+	printk("%s %s", msg, of_node_full_name(args->np));
+	for (i = 0; i < args->args_count; i++)
+		printk(i ? ",%08x" : ":%08x", args->args[i]);
+	printk("\n");
+}
+
+static int __of_parse_phandle_with_args(const struct device_node *np,
+					const char *list_name,
+					const char *cells_name,
+					int cell_count, int index,
+					struct of_phandle_args *out_args)
+{
+	const __be32 *list, *list_end;
+	int rc = 0, size, cur_index = 0;
+	uint32_t count = 0;
+	struct device_node *node = NULL;
+	phandle phandle;
+
+	/* Retrieve the phandle list property */
+	list = of_get_property(np, list_name, &size);
+	if (!list)
+		return -ENOENT;
+	list_end = list + size / sizeof(*list);
+
+	/* Loop over the phandles until all the requested entry is found */
+	while (list < list_end) {
+		rc = -EINVAL;
+		count = 0;
+
+		/*
+		 * If phandle is 0, then it is an empty entry with no
+		 * arguments.  Skip forward to the next entry.
+		 */
+		phandle = be32_to_cpup(list++);
+		if (phandle) {
+			/*
+			 * Find the provider node and parse the #*-cells
+			 * property to determine the argument length.
+			 *
+			 * This is not needed if the cell count is hard-coded
+			 * (i.e. cells_name not set, but cell_count is set),
+			 * except when we're going to return the found node
+			 * below.
+			 */
+			if (cells_name || cur_index == index) {
+				node = of_find_node_by_phandle(phandle);
+				if (!node) {
+					pr_err("%s: could not find phandle\n",
+						np->full_name);
+					goto err;
+				}
+			}
+
+			if (cells_name) {
+				if (of_property_read_u32(node, cells_name,
+							 &count)) {
+					pr_err("%s: could not get %s for %s\n",
+						np->full_name, cells_name,
+						node->full_name);
+					goto err;
+				}
+			} else {
+				count = cell_count;
+			}
+
+			/*
+			 * Make sure that the arguments actually fit in the
+			 * remaining property data length
+			 */
+			if (list + count > list_end) {
+				pr_err("%s: arguments longer than property\n",
+					 np->full_name);
+				goto err;
+			}
+		}
+
+		/*
+		 * All of the error cases above bail out of the loop, so at
+		 * this point, the parsing is successful. If the requested
+		 * index matches, then fill the out_args structure and return,
+		 * or return -ENOENT for an empty entry.
+		 */
+		rc = -ENOENT;
+		if (cur_index == index) {
+			if (!phandle)
+				goto err;
+
+			if (out_args) {
+				int i;
+				if (WARN_ON(count > MAX_PHANDLE_ARGS))
+					count = MAX_PHANDLE_ARGS;
+				out_args->np = node;
+				out_args->args_count = count;
+				for (i = 0; i < count; i++)
+					out_args->args[i] = be32_to_cpup(list++);
+			} else {
+				of_node_put(node);
+			}
+
+			/* Found it! return success */
+			return 0;
+		}
+
+		of_node_put(node);
+		node = NULL;
+		list += count;
+		cur_index++;
+	}
+
+	/*
+	 * Unlock node before returning result; will be one of:
+	 * -ENOENT : index is for empty phandle
+	 * -EINVAL : parsing error on data
+	 * [1..n]  : Number of phandle (count mode; when index = -1)
+	 */
+	rc = index < 0 ? cur_index : -ENOENT;
+ err:
+	if (node)
+		of_node_put(node);
+	return rc;
+}
+
+/**
+ * of_parse_phandle - Resolve a phandle property to a device_node pointer
+ * @np: Pointer to device node holding phandle property
+ * @phandle_name: Name of property holding a phandle value
+ * @index: For properties holding a table of phandles, this is the index into
+ *         the table
+ *
+ * Returns the device_node pointer with refcount incremented.  Use
+ * of_node_put() on it when done.
+ */
+struct device_node *of_parse_phandle(const struct device_node *np,
+				     const char *phandle_name, int index)
+{
+	struct of_phandle_args args;
+
+	if (index < 0)
+		return NULL;
+
+	if (__of_parse_phandle_with_args(np, phandle_name, NULL, 0,
+					 index, &args))
+		return NULL;
+
+	return args.np;
+}
+EXPORT_SYMBOL(of_parse_phandle);
+
+/**
+ * of_parse_phandle_with_args() - Find a node pointed by phandle in a list
+ * @np:		pointer to a device tree node containing a list
+ * @list_name:	property name that contains a list
+ * @cells_name:	property name that specifies phandles' arguments count
+ * @index:	index of a phandle to parse out
+ * @out_args:	optional pointer to output arguments structure (will be filled)
+ *
+ * This function is useful to parse lists of phandles and their arguments.
+ * Returns 0 on success and fills out_args, on error returns appropriate
+ * errno value.
+ *
+ * Caller is responsible to call of_node_put() on the returned out_args->np
+ * pointer.
+ *
+ * Example:
+ *
+ * phandle1: node1 {
+ *	#list-cells = <2>;
+ * }
+ *
+ * phandle2: node2 {
+ *	#list-cells = <1>;
+ * }
+ *
+ * node3 {
+ *	list = <&phandle1 1 2 &phandle2 3>;
+ * }
+ *
+ * To get a device_node of the `node2' node you may call this:
+ * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
+ */
+int of_parse_phandle_with_args(const struct device_node *np, const char *list_name,
+				const char *cells_name, int index,
+				struct of_phandle_args *out_args)
+{
+	if (index < 0)
+		return -EINVAL;
+	return __of_parse_phandle_with_args(np, list_name, cells_name, 0,
+					    index, out_args);
+}
+EXPORT_SYMBOL(of_parse_phandle_with_args);
+
+/**
+ * of_parse_phandle_with_fixed_args() - Find a node pointed by phandle in a list
+ * @np:		pointer to a device tree node containing a list
+ * @list_name:	property name that contains a list
+ * @cell_count: number of argument cells following the phandle
+ * @index:	index of a phandle to parse out
+ * @out_args:	optional pointer to output arguments structure (will be filled)
+ *
+ * This function is useful to parse lists of phandles and their arguments.
+ * Returns 0 on success and fills out_args, on error returns appropriate
+ * errno value.
+ *
+ * Caller is responsible to call of_node_put() on the returned out_args->np
+ * pointer.
+ *
+ * Example:
+ *
+ * phandle1: node1 {
+ * }
+ *
+ * phandle2: node2 {
+ * }
+ *
+ * node3 {
+ *	list = <&phandle1 0 2 &phandle2 2 3>;
+ * }
+ *
+ * To get a device_node of the `node2' node you may call this:
+ * of_parse_phandle_with_fixed_args(node3, "list", 2, 1, &args);
+ */
+int of_parse_phandle_with_fixed_args(const struct device_node *np,
+				const char *list_name, int cell_count,
+				int index, struct of_phandle_args *out_args)
+{
+	if (index < 0)
+		return -EINVAL;
+	return __of_parse_phandle_with_args(np, list_name, NULL, cell_count,
+					   index, out_args);
+}
+EXPORT_SYMBOL(of_parse_phandle_with_fixed_args);
+
+/**
+ * of_count_phandle_with_args() - Find the number of phandles references in a property
+ * @np:		pointer to a device tree node containing a list
+ * @list_name:	property name that contains a list
+ * @cells_name:	property name that specifies phandles' arguments count
+ *
+ * Returns the number of phandle + argument tuples within a property. It
+ * is a typical pattern to encode a list of phandle and variable
+ * arguments into a single property. The number of arguments is encoded
+ * by a property in the phandle-target node. For example, a gpios
+ * property would contain a list of GPIO specifies consisting of a
+ * phandle and 1 or more arguments. The number of arguments are
+ * determined by the #gpio-cells property in the node pointed to by the
+ * phandle.
+ */
+int of_count_phandle_with_args(const struct device_node *np, const char *list_name,
+				const char *cells_name)
+{
+	return __of_parse_phandle_with_args(np, list_name, cells_name, 0, -1,
+					    NULL);
+}
+EXPORT_SYMBOL(of_count_phandle_with_args);
+
+/**
+ * __of_add_property - Add a property to a node without lock operations
+ */
+int __of_add_property(struct device_node *np, struct property *prop)
+{
+	struct property **next;
+
+	prop->next = NULL;
+	next = &np->properties;
+	while (*next) {
+		if (strcmp(prop->name, (*next)->name) == 0)
+			/* duplicate ! don't insert it */
+			return -EEXIST;
+
+		next = &(*next)->next;
+	}
+	*next = prop;
+
+	return 0;
+}
+
+/**
+ * of_add_property - Add a property to a node
+ */
+int of_add_property(struct device_node *np, struct property *prop)
+{
+	unsigned long flags;
+	int rc;
+
+	mutex_lock(&of_mutex);
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	rc = __of_add_property(np, prop);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+	if (!rc)
+		__of_add_property_sysfs(np, prop);
+
+	mutex_unlock(&of_mutex);
+
+	if (!rc)
+		of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop, NULL);
+
+	return rc;
+}
+
+int __of_remove_property(struct device_node *np, struct property *prop)
+{
+	struct property **next;
+
+	for (next = &np->properties; *next; next = &(*next)->next) {
+		if (*next == prop)
+			break;
+	}
+	if (*next == NULL)
+		return -ENODEV;
+
+	/* found the node */
+	*next = prop->next;
+	prop->next = np->deadprops;
+	np->deadprops = prop;
+
+	return 0;
+}
+
+void __of_remove_property_sysfs(struct device_node *np, struct property *prop)
+{
+	if (!IS_ENABLED(CONFIG_SYSFS))
+		return;
+
+	/* at early boot, bail here and defer setup to of_init() */
+	if (of_kset && of_node_is_attached(np))
+		sysfs_remove_bin_file(&np->kobj, &prop->attr);
+}
+
+/**
+ * of_remove_property - Remove a property from a node.
+ *
+ * Note that we don't actually remove it, since we have given out
+ * who-knows-how-many pointers to the data using get-property.
+ * Instead we just move the property to the "dead properties"
+ * list, so it won't be found any more.
+ */
+int of_remove_property(struct device_node *np, struct property *prop)
+{
+	unsigned long flags;
+	int rc;
+
+	mutex_lock(&of_mutex);
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	rc = __of_remove_property(np, prop);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+	if (!rc)
+		__of_remove_property_sysfs(np, prop);
+
+	mutex_unlock(&of_mutex);
+
+	if (!rc)
+		of_property_notify(OF_RECONFIG_REMOVE_PROPERTY, np, prop, NULL);
+
+	return rc;
+}
+
+int __of_update_property(struct device_node *np, struct property *newprop,
+		struct property **oldpropp)
+{
+	struct property **next, *oldprop;
+
+	for (next = &np->properties; *next; next = &(*next)->next) {
+		if (of_prop_cmp((*next)->name, newprop->name) == 0)
+			break;
+	}
+	*oldpropp = oldprop = *next;
+
+	if (oldprop) {
+		/* replace the node */
+		newprop->next = oldprop->next;
+		*next = newprop;
+		oldprop->next = np->deadprops;
+		np->deadprops = oldprop;
+	} else {
+		/* new node */
+		newprop->next = NULL;
+		*next = newprop;
+	}
+
+	return 0;
+}
+
+void __of_update_property_sysfs(struct device_node *np, struct property *newprop,
+		struct property *oldprop)
+{
+	if (!IS_ENABLED(CONFIG_SYSFS))
+		return;
+
+	/* At early boot, bail out and defer setup to of_init() */
+	if (!of_kset)
+		return;
+
+	if (oldprop)
+		sysfs_remove_bin_file(&np->kobj, &oldprop->attr);
+	__of_add_property_sysfs(np, newprop);
+}
+
+/*
+ * of_update_property - Update a property in a node, if the property does
+ * not exist, add it.
+ *
+ * Note that we don't actually remove it, since we have given out
+ * who-knows-how-many pointers to the data using get-property.
+ * Instead we just move the property to the "dead properties" list,
+ * and add the new property to the property list
+ */
+int of_update_property(struct device_node *np, struct property *newprop)
+{
+	struct property *oldprop;
+	unsigned long flags;
+	int rc;
+
+	if (!newprop->name)
+		return -EINVAL;
+
+	mutex_lock(&of_mutex);
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	rc = __of_update_property(np, newprop, &oldprop);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+	if (!rc)
+		__of_update_property_sysfs(np, newprop, oldprop);
+
+	mutex_unlock(&of_mutex);
+
+	if (!rc)
+		of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop, oldprop);
+
+	return rc;
+}
+
+static void of_alias_add(struct alias_prop *ap, struct device_node *np,
+			 int id, const char *stem, int stem_len)
+{
+	ap->np = np;
+	ap->id = id;
+	strncpy(ap->stem, stem, stem_len);
+	ap->stem[stem_len] = 0;
+	list_add_tail(&ap->link, &aliases_lookup);
+	pr_debug("adding DT alias:%s: stem=%s id=%i node=%s\n",
+		 ap->alias, ap->stem, ap->id, of_node_full_name(np));
+}
+
+/**
+ * of_alias_scan - Scan all properties of the 'aliases' node
+ *
+ * The function scans all the properties of the 'aliases' node and populates
+ * the global lookup table with the properties.  It returns the
+ * number of alias properties found, or an error code in case of failure.
+ *
+ * @dt_alloc:	An allocator that provides a virtual address to memory
+ *		for storing the resulting tree
+ */
+void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align))
+{
+	struct property *pp;
+
+	of_aliases = of_find_node_by_path("/aliases");
+	of_chosen = of_find_node_by_path("/chosen");
+	if (of_chosen == NULL)
+		of_chosen = of_find_node_by_path("/chosen@0");
+
+	if (of_chosen) {
+		/* linux,stdout-path and /aliases/stdout are for legacy compatibility */
+		const char *name = of_get_property(of_chosen, "stdout-path", NULL);
+		if (!name)
+			name = of_get_property(of_chosen, "linux,stdout-path", NULL);
+		if (IS_ENABLED(CONFIG_PPC) && !name)
+			name = of_get_property(of_aliases, "stdout", NULL);
+		if (name)
+			of_stdout = of_find_node_opts_by_path(name, &of_stdout_options);
+	}
+
+	if (!of_aliases)
+		return;
+
+	for_each_property_of_node(of_aliases, pp) {
+		const char *start = pp->name;
+		const char *end = start + strlen(start);
+		struct device_node *np;
+		struct alias_prop *ap;
+		int id, len;
+
+		/* Skip those we do not want to proceed */
+		if (!strcmp(pp->name, "name") ||
+		    !strcmp(pp->name, "phandle") ||
+		    !strcmp(pp->name, "linux,phandle"))
+			continue;
+
+		np = of_find_node_by_path(pp->value);
+		if (!np)
+			continue;
+
+		/* walk the alias backwards to extract the id and work out
+		 * the 'stem' string */
+		while (isdigit(*(end-1)) && end > start)
+			end--;
+		len = end - start;
+
+		if (kstrtoint(end, 10, &id) < 0)
+			continue;
+
+		/* Allocate an alias_prop with enough space for the stem */
+		ap = dt_alloc(sizeof(*ap) + len + 1, 4);
+		if (!ap)
+			continue;
+		memset(ap, 0, sizeof(*ap) + len + 1);
+		ap->alias = start;
+		of_alias_add(ap, np, id, start, len);
+	}
+}
+
+/**
+ * of_alias_get_id - Get alias id for the given device_node
+ * @np:		Pointer to the given device_node
+ * @stem:	Alias stem of the given device_node
+ *
+ * The function travels the lookup table to get the alias id for the given
+ * device_node and alias stem.  It returns the alias id if found.
+ */
+int of_alias_get_id(struct device_node *np, const char *stem)
+{
+	struct alias_prop *app;
+	int id = -ENODEV;
+
+	mutex_lock(&of_mutex);
+	list_for_each_entry(app, &aliases_lookup, link) {
+		if (strcmp(app->stem, stem) != 0)
+			continue;
+
+		if (np == app->np) {
+			id = app->id;
+			break;
+		}
+	}
+	mutex_unlock(&of_mutex);
+
+	return id;
+}
+EXPORT_SYMBOL_GPL(of_alias_get_id);
+
+/**
+ * of_alias_get_highest_id - Get highest alias id for the given stem
+ * @stem:	Alias stem to be examined
+ *
+ * The function travels the lookup table to get the highest alias id for the
+ * given alias stem.  It returns the alias id if found.
+ */
+int of_alias_get_highest_id(const char *stem)
+{
+	struct alias_prop *app;
+	int id = -ENODEV;
+
+	mutex_lock(&of_mutex);
+	list_for_each_entry(app, &aliases_lookup, link) {
+		if (strcmp(app->stem, stem) != 0)
+			continue;
+
+		if (app->id > id)
+			id = app->id;
+	}
+	mutex_unlock(&of_mutex);
+
+	return id;
+}
+EXPORT_SYMBOL_GPL(of_alias_get_highest_id);
+
+const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur,
+			       u32 *pu)
+{
+	const void *curv = cur;
+
+	if (!prop)
+		return NULL;
+
+	if (!cur) {
+		curv = prop->value;
+		goto out_val;
+	}
+
+	curv += sizeof(*cur);
+	if (curv >= prop->value + prop->length)
+		return NULL;
+
+out_val:
+	*pu = be32_to_cpup(curv);
+	return curv;
+}
+EXPORT_SYMBOL_GPL(of_prop_next_u32);
+
+const char *of_prop_next_string(struct property *prop, const char *cur)
+{
+	const void *curv = cur;
+
+	if (!prop)
+		return NULL;
+
+	if (!cur)
+		return prop->value;
+
+	curv += strlen(cur) + 1;
+	if (curv >= prop->value + prop->length)
+		return NULL;
+
+	return curv;
+}
+EXPORT_SYMBOL_GPL(of_prop_next_string);
+
+/**
+ * of_console_check() - Test and setup console for DT setup
+ * @dn - Pointer to device node
+ * @name - Name to use for preferred console without index. ex. "ttyS"
+ * @index - Index to use for preferred console.
+ *
+ * Check if the given device node matches the stdout-path property in the
+ * /chosen node. If it does then register it as the preferred console and return
+ * TRUE. Otherwise return FALSE.
+ */
+bool of_console_check(struct device_node *dn, char *name, int index)
+{
+	if (!dn || dn != of_stdout || console_set_on_cmdline)
+		return false;
+	return !add_preferred_console(name, index,
+				      kstrdup(of_stdout_options, GFP_KERNEL));
+}
+EXPORT_SYMBOL_GPL(of_console_check);
+
+/**
+ *	of_find_next_cache_node - Find a node's subsidiary cache
+ *	@np:	node of type "cpu" or "cache"
+ *
+ *	Returns a node pointer with refcount incremented, use
+ *	of_node_put() on it when done.  Caller should hold a reference
+ *	to np.
+ */
+struct device_node *of_find_next_cache_node(const struct device_node *np)
+{
+	struct device_node *child;
+	const phandle *handle;
+
+	handle = of_get_property(np, "l2-cache", NULL);
+	if (!handle)
+		handle = of_get_property(np, "next-level-cache", NULL);
+
+	if (handle)
+		return of_find_node_by_phandle(be32_to_cpup(handle));
+
+	/* OF on pmac has nodes instead of properties named "l2-cache"
+	 * beneath CPU nodes.
+	 */
+	if (!strcmp(np->type, "cpu"))
+		for_each_child_of_node(np, child)
+			if (!strcmp(child->type, "cache"))
+				return child;
+
+	return NULL;
+}
+
+/**
+ * of_graph_parse_endpoint() - parse common endpoint node properties
+ * @node: pointer to endpoint device_node
+ * @endpoint: pointer to the OF endpoint data structure
+ *
+ * The caller should hold a reference to @node.
+ */
+int of_graph_parse_endpoint(const struct device_node *node,
+			    struct of_endpoint *endpoint)
+{
+	struct device_node *port_node = of_get_parent(node);
+
+	WARN_ONCE(!port_node, "%s(): endpoint %s has no parent node\n",
+		  __func__, node->full_name);
+
+	memset(endpoint, 0, sizeof(*endpoint));
+
+	endpoint->local_node = node;
+	/*
+	 * It doesn't matter whether the two calls below succeed.
+	 * If they don't then the default value 0 is used.
+	 */
+	of_property_read_u32(port_node, "reg", &endpoint->port);
+	of_property_read_u32(node, "reg", &endpoint->id);
+
+	of_node_put(port_node);
+
+	return 0;
+}
+EXPORT_SYMBOL(of_graph_parse_endpoint);
+
+/**
+ * of_graph_get_port_by_id() - get the port matching a given id
+ * @parent: pointer to the parent device node
+ * @id: id of the port
+ *
+ * Return: A 'port' node pointer with refcount incremented. The caller
+ * has to use of_node_put() on it when done.
+ */
+struct device_node *of_graph_get_port_by_id(struct device_node *parent, u32 id)
+{
+	struct device_node *node, *port;
+
+	node = of_get_child_by_name(parent, "ports");
+	if (node)
+		parent = node;
+
+	for_each_child_of_node(parent, port) {
+		u32 port_id = 0;
+
+		if (of_node_cmp(port->name, "port") != 0)
+			continue;
+		of_property_read_u32(port, "reg", &port_id);
+		if (id == port_id)
+			break;
+	}
+
+	of_node_put(node);
+
+	return port;
+}
+EXPORT_SYMBOL(of_graph_get_port_by_id);
+
+/**
+ * of_graph_get_next_endpoint() - get next endpoint node
+ * @parent: pointer to the parent device node
+ * @prev: previous endpoint node, or NULL to get first
+ *
+ * Return: An 'endpoint' node pointer with refcount incremented. Refcount
+ * of the passed @prev node is decremented.
+ */
+struct device_node *of_graph_get_next_endpoint(const struct device_node *parent,
+					struct device_node *prev)
+{
+	struct device_node *endpoint;
+	struct device_node *port;
+
+	if (!parent)
+		return NULL;
+
+	/*
+	 * Start by locating the port node. If no previous endpoint is specified
+	 * search for the first port node, otherwise get the previous endpoint
+	 * parent port node.
+	 */
+	if (!prev) {
+		struct device_node *node;
+
+		node = of_get_child_by_name(parent, "ports");
+		if (node)
+			parent = node;
+
+		port = of_get_child_by_name(parent, "port");
+		of_node_put(node);
+
+		if (!port) {
+			pr_err("%s(): no port node found in %s\n",
+			       __func__, parent->full_name);
+			return NULL;
+		}
+	} else {
+		port = of_get_parent(prev);
+		if (WARN_ONCE(!port, "%s(): endpoint %s has no parent node\n",
+			      __func__, prev->full_name))
+			return NULL;
+	}
+
+	while (1) {
+		/*
+		 * Now that we have a port node, get the next endpoint by
+		 * getting the next child. If the previous endpoint is NULL this
+		 * will return the first child.
+		 */
+		endpoint = of_get_next_child(port, prev);
+		if (endpoint) {
+			of_node_put(port);
+			return endpoint;
+		}
+
+		/* No more endpoints under this port, try the next one. */
+		prev = NULL;
+
+		do {
+			port = of_get_next_child(parent, port);
+			if (!port)
+				return NULL;
+		} while (of_node_cmp(port->name, "port"));
+	}
+}
+EXPORT_SYMBOL(of_graph_get_next_endpoint);
+
+/**
+ * of_graph_get_remote_port_parent() - get remote port's parent node
+ * @node: pointer to a local endpoint device_node
+ *
+ * Return: Remote device node associated with remote endpoint node linked
+ *	   to @node. Use of_node_put() on it when done.
+ */
+struct device_node *of_graph_get_remote_port_parent(
+			       const struct device_node *node)
+{
+	struct device_node *np;
+	unsigned int depth;
+
+	/* Get remote endpoint node. */
+	np = of_parse_phandle(node, "remote-endpoint", 0);
+
+	/* Walk 3 levels up only if there is 'ports' node. */
+	for (depth = 3; depth && np; depth--) {
+		np = of_get_next_parent(np);
+		if (depth == 2 && of_node_cmp(np->name, "ports"))
+			break;
+	}
+	return np;
+}
+EXPORT_SYMBOL(of_graph_get_remote_port_parent);
+
+/**
+ * of_graph_get_remote_port() - get remote port node
+ * @node: pointer to a local endpoint device_node
+ *
+ * Return: Remote port node associated with remote endpoint node linked
+ *	   to @node. Use of_node_put() on it when done.
+ */
+struct device_node *of_graph_get_remote_port(const struct device_node *node)
+{
+	struct device_node *np;
+
+	/* Get remote endpoint node. */
+	np = of_parse_phandle(node, "remote-endpoint", 0);
+	if (!np)
+		return NULL;
+	return of_get_next_parent(np);
+}
+EXPORT_SYMBOL(of_graph_get_remote_port);
diff --git a/kernel/drivers/of/device.c b/kernel/drivers/of/device.c
new file mode 100644
index 000000000..20c1332a0
--- /dev/null
+++ b/kernel/drivers/of/device.c
@@ -0,0 +1,276 @@
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+#include <linux/of_iommu.h>
+#include <linux/dma-mapping.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/slab.h>
+
+#include <asm/errno.h>
+#include "of_private.h"
+
+/**
+ * of_match_device - Tell if a struct device matches an of_device_id list
+ * @ids: array of of device match structures to search in
+ * @dev: the of device structure to match against
+ *
+ * Used by a driver to check whether an platform_device present in the
+ * system is in its list of supported devices.
+ */
+const struct of_device_id *of_match_device(const struct of_device_id *matches,
+					   const struct device *dev)
+{
+	if ((!matches) || (!dev->of_node))
+		return NULL;
+	return of_match_node(matches, dev->of_node);
+}
+EXPORT_SYMBOL(of_match_device);
+
+struct platform_device *of_dev_get(struct platform_device *dev)
+{
+	struct device *tmp;
+
+	if (!dev)
+		return NULL;
+	tmp = get_device(&dev->dev);
+	if (tmp)
+		return to_platform_device(tmp);
+	else
+		return NULL;
+}
+EXPORT_SYMBOL(of_dev_get);
+
+void of_dev_put(struct platform_device *dev)
+{
+	if (dev)
+		put_device(&dev->dev);
+}
+EXPORT_SYMBOL(of_dev_put);
+
+int of_device_add(struct platform_device *ofdev)
+{
+	BUG_ON(ofdev->dev.of_node == NULL);
+
+	/* name and id have to be set so that the platform bus doesn't get
+	 * confused on matching */
+	ofdev->name = dev_name(&ofdev->dev);
+	ofdev->id = -1;
+
+	/* device_add will assume that this device is on the same node as
+	 * the parent. If there is no parent defined, set the node
+	 * explicitly */
+	if (!ofdev->dev.parent)
+		set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node));
+
+	return device_add(&ofdev->dev);
+}
+
+/**
+ * of_dma_configure - Setup DMA configuration
+ * @dev:	Device to apply DMA configuration
+ * @np:		Pointer to OF node having DMA configuration
+ *
+ * Try to get devices's DMA configuration from DT and update it
+ * accordingly.
+ *
+ * If platform code needs to use its own special DMA configuration, it
+ * can use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE events
+ * to fix up DMA configuration.
+ */
+void of_dma_configure(struct device *dev, struct device_node *np)
+{
+	u64 dma_addr, paddr, size;
+	int ret;
+	bool coherent;
+	unsigned long offset;
+	struct iommu_ops *iommu;
+
+	/*
+	 * Set default coherent_dma_mask to 32 bit.  Drivers are expected to
+	 * setup the correct supported mask.
+	 */
+	if (!dev->coherent_dma_mask)
+		dev->coherent_dma_mask = DMA_BIT_MASK(32);
+
+	/*
+	 * Set it to coherent_dma_mask by default if the architecture
+	 * code has not set it.
+	 */
+	if (!dev->dma_mask)
+		dev->dma_mask = &dev->coherent_dma_mask;
+
+	ret = of_dma_get_range(np, &dma_addr, &paddr, &size);
+	if (ret < 0) {
+		dma_addr = offset = 0;
+		size = dev->coherent_dma_mask + 1;
+	} else {
+		offset = PFN_DOWN(paddr - dma_addr);
+
+		/*
+		 * Add a work around to treat the size as mask + 1 in case
+		 * it is defined in DT as a mask.
+		 */
+		if (size & 1) {
+			dev_warn(dev, "Invalid size 0x%llx for dma-range\n",
+				 size);
+			size = size + 1;
+		}
+
+		if (!size) {
+			dev_err(dev, "Adjusted size 0x%llx invalid\n", size);
+			return;
+		}
+		dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
+	}
+
+	dev->dma_pfn_offset = offset;
+
+	/*
+	 * Limit coherent and dma mask based on size and default mask
+	 * set by the driver.
+	 */
+	dev->coherent_dma_mask = min(dev->coherent_dma_mask,
+				     DMA_BIT_MASK(ilog2(dma_addr + size)));
+	*dev->dma_mask = min((*dev->dma_mask),
+			     DMA_BIT_MASK(ilog2(dma_addr + size)));
+
+	coherent = of_dma_is_coherent(np);
+	dev_dbg(dev, "device is%sdma coherent\n",
+		coherent ? " " : " not ");
+
+	iommu = of_iommu_configure(dev, np);
+	dev_dbg(dev, "device is%sbehind an iommu\n",
+		iommu ? " " : " not ");
+
+	arch_setup_dma_ops(dev, dma_addr, size, iommu, coherent);
+}
+EXPORT_SYMBOL_GPL(of_dma_configure);
+
+int of_device_register(struct platform_device *pdev)
+{
+	device_initialize(&pdev->dev);
+	return of_device_add(pdev);
+}
+EXPORT_SYMBOL(of_device_register);
+
+void of_device_unregister(struct platform_device *ofdev)
+{
+	device_unregister(&ofdev->dev);
+}
+EXPORT_SYMBOL(of_device_unregister);
+
+ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
+{
+	const char *compat;
+	int cplen, i;
+	ssize_t tsize, csize, repend;
+
+	if ((!dev) || (!dev->of_node))
+		return -ENODEV;
+
+	/* Name & Type */
+	csize = snprintf(str, len, "of:N%sT%s", dev->of_node->name,
+			 dev->of_node->type);
+
+	/* Get compatible property if any */
+	compat = of_get_property(dev->of_node, "compatible", &cplen);
+	if (!compat)
+		return csize;
+
+	/* Find true end (we tolerate multiple \0 at the end */
+	for (i = (cplen - 1); i >= 0 && !compat[i]; i--)
+		cplen--;
+	if (!cplen)
+		return csize;
+	cplen++;
+
+	/* Check space (need cplen+1 chars including final \0) */
+	tsize = csize + cplen;
+	repend = tsize;
+
+	if (csize >= len)		/* @ the limit, all is already filled */
+		return tsize;
+
+	if (tsize >= len) {		/* limit compat list */
+		cplen = len - csize - 1;
+		repend = len;
+	}
+
+	/* Copy and do char replacement */
+	memcpy(&str[csize + 1], compat, cplen);
+	for (i = csize; i < repend; i++) {
+		char c = str[i];
+		if (c == '\0')
+			str[i] = 'C';
+		else if (c == ' ')
+			str[i] = '_';
+	}
+
+	return tsize;
+}
+
+/**
+ * of_device_uevent - Display OF related uevent information
+ */
+void of_device_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	const char *compat;
+	struct alias_prop *app;
+	int seen = 0, cplen, sl;
+
+	if ((!dev) || (!dev->of_node))
+		return;
+
+	add_uevent_var(env, "OF_NAME=%s", dev->of_node->name);
+	add_uevent_var(env, "OF_FULLNAME=%s", dev->of_node->full_name);
+	if (dev->of_node->type && strcmp("<NULL>", dev->of_node->type) != 0)
+		add_uevent_var(env, "OF_TYPE=%s", dev->of_node->type);
+
+	/* Since the compatible field can contain pretty much anything
+	 * it's not really legal to split it out with commas. We split it
+	 * up using a number of environment variables instead. */
+	compat = of_get_property(dev->of_node, "compatible", &cplen);
+	while (compat && *compat && cplen > 0) {
+		add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);
+		sl = strlen(compat) + 1;
+		compat += sl;
+		cplen -= sl;
+		seen++;
+	}
+	add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
+
+	seen = 0;
+	mutex_lock(&of_mutex);
+	list_for_each_entry(app, &aliases_lookup, link) {
+		if (dev->of_node == app->np) {
+			add_uevent_var(env, "OF_ALIAS_%d=%s", seen,
+				       app->alias);
+			seen++;
+		}
+	}
+	mutex_unlock(&of_mutex);
+}
+
+int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
+{
+	int sl;
+
+	if ((!dev) || (!dev->of_node))
+		return -ENODEV;
+
+	/* Devicetree modalias is tricky, we add it in 2 steps */
+	if (add_uevent_var(env, "MODALIAS="))
+		return -ENOMEM;
+
+	sl = of_device_get_modalias(dev, &env->buf[env->buflen-1],
+				    sizeof(env->buf) - env->buflen);
+	if (sl >= (sizeof(env->buf) - env->buflen))
+		return -ENOMEM;
+	env->buflen += sl;
+
+	return 0;
+}
diff --git a/kernel/drivers/of/dynamic.c b/kernel/drivers/of/dynamic.c
new file mode 100644
index 000000000..53826b84e
--- /dev/null
+++ b/kernel/drivers/of/dynamic.c
@@ -0,0 +1,781 @@
+/*
+ * Support for dynamic device trees.
+ *
+ * On some platforms, the device tree can be manipulated at runtime.
+ * The routines in this section support adding, removing and changing
+ * device tree nodes.
+ */
+
+#include <linux/of.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/proc_fs.h>
+
+#include "of_private.h"
+
+/**
+ * of_node_get() - Increment refcount of a node
+ * @node:	Node to inc refcount, NULL is supported to simplify writing of
+ *		callers
+ *
+ * Returns node.
+ */
+struct device_node *of_node_get(struct device_node *node)
+{
+	if (node)
+		kobject_get(&node->kobj);
+	return node;
+}
+EXPORT_SYMBOL(of_node_get);
+
+/**
+ * of_node_put() - Decrement refcount of a node
+ * @node:	Node to dec refcount, NULL is supported to simplify writing of
+ *		callers
+ */
+void of_node_put(struct device_node *node)
+{
+	if (node)
+		kobject_put(&node->kobj);
+}
+EXPORT_SYMBOL(of_node_put);
+
+void __of_detach_node_sysfs(struct device_node *np)
+{
+	struct property *pp;
+
+	if (!IS_ENABLED(CONFIG_SYSFS))
+		return;
+
+	BUG_ON(!of_node_is_initialized(np));
+	if (!of_kset)
+		return;
+
+	/* only remove properties if on sysfs */
+	if (of_node_is_attached(np)) {
+		for_each_property_of_node(np, pp)
+			sysfs_remove_bin_file(&np->kobj, &pp->attr);
+		kobject_del(&np->kobj);
+	}
+
+	/* finally remove the kobj_init ref */
+	of_node_put(np);
+}
+
+static BLOCKING_NOTIFIER_HEAD(of_reconfig_chain);
+
+int of_reconfig_notifier_register(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_register(&of_reconfig_chain, nb);
+}
+EXPORT_SYMBOL_GPL(of_reconfig_notifier_register);
+
+int of_reconfig_notifier_unregister(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_unregister(&of_reconfig_chain, nb);
+}
+EXPORT_SYMBOL_GPL(of_reconfig_notifier_unregister);
+
+#ifdef DEBUG
+const char *action_names[] = {
+	[OF_RECONFIG_ATTACH_NODE] = "ATTACH_NODE",
+	[OF_RECONFIG_DETACH_NODE] = "DETACH_NODE",
+	[OF_RECONFIG_ADD_PROPERTY] = "ADD_PROPERTY",
+	[OF_RECONFIG_REMOVE_PROPERTY] = "REMOVE_PROPERTY",
+	[OF_RECONFIG_UPDATE_PROPERTY] = "UPDATE_PROPERTY",
+};
+#endif
+
+int of_reconfig_notify(unsigned long action, struct of_reconfig_data *p)
+{
+	int rc;
+#ifdef DEBUG
+	struct of_reconfig_data *pr = p;
+
+	switch (action) {
+	case OF_RECONFIG_ATTACH_NODE:
+	case OF_RECONFIG_DETACH_NODE:
+		pr_debug("of/notify %-15s %s\n", action_names[action],
+			pr->dn->full_name);
+		break;
+	case OF_RECONFIG_ADD_PROPERTY:
+	case OF_RECONFIG_REMOVE_PROPERTY:
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		pr_debug("of/notify %-15s %s:%s\n", action_names[action],
+			pr->dn->full_name, pr->prop->name);
+		break;
+
+	}
+#endif
+	rc = blocking_notifier_call_chain(&of_reconfig_chain, action, p);
+	return notifier_to_errno(rc);
+}
+
+/*
+ * of_reconfig_get_state_change()	- Returns new state of device
+ * @action	- action of the of notifier
+ * @arg		- argument of the of notifier
+ *
+ * Returns the new state of a device based on the notifier used.
+ * Returns 0 on device going from enabled to disabled, 1 on device
+ * going from disabled to enabled and -1 on no change.
+ */
+int of_reconfig_get_state_change(unsigned long action, struct of_reconfig_data *pr)
+{
+	struct property *prop, *old_prop = NULL;
+	int is_status, status_state, old_status_state, prev_state, new_state;
+
+	/* figure out if a device should be created or destroyed */
+	switch (action) {
+	case OF_RECONFIG_ATTACH_NODE:
+	case OF_RECONFIG_DETACH_NODE:
+		prop = of_find_property(pr->dn, "status", NULL);
+		break;
+	case OF_RECONFIG_ADD_PROPERTY:
+	case OF_RECONFIG_REMOVE_PROPERTY:
+		prop = pr->prop;
+		break;
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		prop = pr->prop;
+		old_prop = pr->old_prop;
+		break;
+	default:
+		return OF_RECONFIG_NO_CHANGE;
+	}
+
+	is_status = 0;
+	status_state = -1;
+	old_status_state = -1;
+	prev_state = -1;
+	new_state = -1;
+
+	if (prop && !strcmp(prop->name, "status")) {
+		is_status = 1;
+		status_state = !strcmp(prop->value, "okay") ||
+			       !strcmp(prop->value, "ok");
+		if (old_prop)
+			old_status_state = !strcmp(old_prop->value, "okay") ||
+					   !strcmp(old_prop->value, "ok");
+	}
+
+	switch (action) {
+	case OF_RECONFIG_ATTACH_NODE:
+		prev_state = 0;
+		/* -1 & 0 status either missing or okay */
+		new_state = status_state != 0;
+		break;
+	case OF_RECONFIG_DETACH_NODE:
+		/* -1 & 0 status either missing or okay */
+		prev_state = status_state != 0;
+		new_state = 0;
+		break;
+	case OF_RECONFIG_ADD_PROPERTY:
+		if (is_status) {
+			/* no status property -> enabled (legacy) */
+			prev_state = 1;
+			new_state = status_state;
+		}
+		break;
+	case OF_RECONFIG_REMOVE_PROPERTY:
+		if (is_status) {
+			prev_state = status_state;
+			/* no status property -> enabled (legacy) */
+			new_state = 1;
+		}
+		break;
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		if (is_status) {
+			prev_state = old_status_state != 0;
+			new_state = status_state != 0;
+		}
+		break;
+	}
+
+	if (prev_state == new_state)
+		return OF_RECONFIG_NO_CHANGE;
+
+	return new_state ? OF_RECONFIG_CHANGE_ADD : OF_RECONFIG_CHANGE_REMOVE;
+}
+EXPORT_SYMBOL_GPL(of_reconfig_get_state_change);
+
+int of_property_notify(int action, struct device_node *np,
+		       struct property *prop, struct property *oldprop)
+{
+	struct of_reconfig_data pr;
+
+	/* only call notifiers if the node is attached */
+	if (!of_node_is_attached(np))
+		return 0;
+
+	pr.dn = np;
+	pr.prop = prop;
+	pr.old_prop = oldprop;
+	return of_reconfig_notify(action, &pr);
+}
+
+void __of_attach_node(struct device_node *np)
+{
+	const __be32 *phandle;
+	int sz;
+
+	np->name = __of_get_property(np, "name", NULL) ? : "<NULL>";
+	np->type = __of_get_property(np, "device_type", NULL) ? : "<NULL>";
+
+	phandle = __of_get_property(np, "phandle", &sz);
+	if (!phandle)
+		phandle = __of_get_property(np, "linux,phandle", &sz);
+	if (IS_ENABLED(CONFIG_PPC_PSERIES) && !phandle)
+		phandle = __of_get_property(np, "ibm,phandle", &sz);
+	np->phandle = (phandle && (sz >= 4)) ? be32_to_cpup(phandle) : 0;
+
+	np->child = NULL;
+	np->sibling = np->parent->child;
+	np->parent->child = np;
+	of_node_clear_flag(np, OF_DETACHED);
+}
+
+/**
+ * of_attach_node() - Plug a device node into the tree and global list.
+ */
+int of_attach_node(struct device_node *np)
+{
+	struct of_reconfig_data rd;
+	unsigned long flags;
+
+	memset(&rd, 0, sizeof(rd));
+	rd.dn = np;
+
+	mutex_lock(&of_mutex);
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	__of_attach_node(np);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+	__of_attach_node_sysfs(np);
+	mutex_unlock(&of_mutex);
+
+	of_reconfig_notify(OF_RECONFIG_ATTACH_NODE, &rd);
+
+	return 0;
+}
+
+void __of_detach_node(struct device_node *np)
+{
+	struct device_node *parent;
+
+	if (WARN_ON(of_node_check_flag(np, OF_DETACHED)))
+		return;
+
+	parent = np->parent;
+	if (WARN_ON(!parent))
+		return;
+
+	if (parent->child == np)
+		parent->child = np->sibling;
+	else {
+		struct device_node *prevsib;
+		for (prevsib = np->parent->child;
+		     prevsib->sibling != np;
+		     prevsib = prevsib->sibling)
+			;
+		prevsib->sibling = np->sibling;
+	}
+
+	of_node_set_flag(np, OF_DETACHED);
+}
+
+/**
+ * of_detach_node() - "Unplug" a node from the device tree.
+ *
+ * The caller must hold a reference to the node.  The memory associated with
+ * the node is not freed until its refcount goes to zero.
+ */
+int of_detach_node(struct device_node *np)
+{
+	struct of_reconfig_data rd;
+	unsigned long flags;
+	int rc = 0;
+
+	memset(&rd, 0, sizeof(rd));
+	rd.dn = np;
+
+	mutex_lock(&of_mutex);
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	__of_detach_node(np);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+	__of_detach_node_sysfs(np);
+	mutex_unlock(&of_mutex);
+
+	of_reconfig_notify(OF_RECONFIG_DETACH_NODE, &rd);
+
+	return rc;
+}
+
+/**
+ * of_node_release() - release a dynamically allocated node
+ * @kref: kref element of the node to be released
+ *
+ * In of_node_put() this function is passed to kref_put() as the destructor.
+ */
+void of_node_release(struct kobject *kobj)
+{
+	struct device_node *node = kobj_to_device_node(kobj);
+	struct property *prop = node->properties;
+
+	/* We should never be releasing nodes that haven't been detached. */
+	if (!of_node_check_flag(node, OF_DETACHED)) {
+		pr_err("ERROR: Bad of_node_put() on %s\n", node->full_name);
+		dump_stack();
+		return;
+	}
+
+	if (!of_node_check_flag(node, OF_DYNAMIC))
+		return;
+
+	while (prop) {
+		struct property *next = prop->next;
+		kfree(prop->name);
+		kfree(prop->value);
+		kfree(prop);
+		prop = next;
+
+		if (!prop) {
+			prop = node->deadprops;
+			node->deadprops = NULL;
+		}
+	}
+	kfree(node->full_name);
+	kfree(node->data);
+	kfree(node);
+}
+
+/**
+ * __of_prop_dup - Copy a property dynamically.
+ * @prop:	Property to copy
+ * @allocflags:	Allocation flags (typically pass GFP_KERNEL)
+ *
+ * Copy a property by dynamically allocating the memory of both the
+ * property structure and the property name & contents. The property's
+ * flags have the OF_DYNAMIC bit set so that we can differentiate between
+ * dynamically allocated properties and not.
+ * Returns the newly allocated property or NULL on out of memory error.
+ */
+struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags)
+{
+	struct property *new;
+
+	new = kzalloc(sizeof(*new), allocflags);
+	if (!new)
+		return NULL;
+
+	/*
+	 * NOTE: There is no check for zero length value.
+	 * In case of a boolean property, this will allocate a value
+	 * of zero bytes. We do this to work around the use
+	 * of of_get_property() calls on boolean values.
+	 */
+	new->name = kstrdup(prop->name, allocflags);
+	new->value = kmemdup(prop->value, prop->length, allocflags);
+	new->length = prop->length;
+	if (!new->name || !new->value)
+		goto err_free;
+
+	/* mark the property as dynamic */
+	of_property_set_flag(new, OF_DYNAMIC);
+
+	return new;
+
+ err_free:
+	kfree(new->name);
+	kfree(new->value);
+	kfree(new);
+	return NULL;
+}
+
+/**
+ * __of_node_dup() - Duplicate or create an empty device node dynamically.
+ * @fmt: Format string (plus vargs) for new full name of the device node
+ *
+ * Create an device tree node, either by duplicating an empty node or by allocating
+ * an empty one suitable for further modification.  The node data are
+ * dynamically allocated and all the node flags have the OF_DYNAMIC &
+ * OF_DETACHED bits set. Returns the newly allocated node or NULL on out of
+ * memory error.
+ */
+struct device_node *__of_node_dup(const struct device_node *np, const char *fmt, ...)
+{
+	va_list vargs;
+	struct device_node *node;
+
+	node = kzalloc(sizeof(*node), GFP_KERNEL);
+	if (!node)
+		return NULL;
+	va_start(vargs, fmt);
+	node->full_name = kvasprintf(GFP_KERNEL, fmt, vargs);
+	va_end(vargs);
+	if (!node->full_name) {
+		kfree(node);
+		return NULL;
+	}
+
+	of_node_set_flag(node, OF_DYNAMIC);
+	of_node_set_flag(node, OF_DETACHED);
+	of_node_init(node);
+
+	/* Iterate over and duplicate all properties */
+	if (np) {
+		struct property *pp, *new_pp;
+		for_each_property_of_node(np, pp) {
+			new_pp = __of_prop_dup(pp, GFP_KERNEL);
+			if (!new_pp)
+				goto err_prop;
+			if (__of_add_property(node, new_pp)) {
+				kfree(new_pp->name);
+				kfree(new_pp->value);
+				kfree(new_pp);
+				goto err_prop;
+			}
+		}
+	}
+	return node;
+
+ err_prop:
+	of_node_put(node); /* Frees the node and properties */
+	return NULL;
+}
+
+static void __of_changeset_entry_destroy(struct of_changeset_entry *ce)
+{
+	of_node_put(ce->np);
+	list_del(&ce->node);
+	kfree(ce);
+}
+
+#ifdef DEBUG
+static void __of_changeset_entry_dump(struct of_changeset_entry *ce)
+{
+	switch (ce->action) {
+	case OF_RECONFIG_ADD_PROPERTY:
+	case OF_RECONFIG_REMOVE_PROPERTY:
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		pr_debug("of/cset<%p> %-15s %s/%s\n", ce, action_names[ce->action],
+			ce->np->full_name, ce->prop->name);
+		break;
+	case OF_RECONFIG_ATTACH_NODE:
+	case OF_RECONFIG_DETACH_NODE:
+		pr_debug("of/cset<%p> %-15s %s\n", ce, action_names[ce->action],
+			ce->np->full_name);
+		break;
+	}
+}
+#else
+static inline void __of_changeset_entry_dump(struct of_changeset_entry *ce)
+{
+	/* empty */
+}
+#endif
+
+static void __of_changeset_entry_invert(struct of_changeset_entry *ce,
+					  struct of_changeset_entry *rce)
+{
+	memcpy(rce, ce, sizeof(*rce));
+
+	switch (ce->action) {
+	case OF_RECONFIG_ATTACH_NODE:
+		rce->action = OF_RECONFIG_DETACH_NODE;
+		break;
+	case OF_RECONFIG_DETACH_NODE:
+		rce->action = OF_RECONFIG_ATTACH_NODE;
+		break;
+	case OF_RECONFIG_ADD_PROPERTY:
+		rce->action = OF_RECONFIG_REMOVE_PROPERTY;
+		break;
+	case OF_RECONFIG_REMOVE_PROPERTY:
+		rce->action = OF_RECONFIG_ADD_PROPERTY;
+		break;
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		rce->old_prop = ce->prop;
+		rce->prop = ce->old_prop;
+		break;
+	}
+}
+
+static void __of_changeset_entry_notify(struct of_changeset_entry *ce, bool revert)
+{
+	struct of_reconfig_data rd;
+	struct of_changeset_entry ce_inverted;
+	int ret;
+
+	if (revert) {
+		__of_changeset_entry_invert(ce, &ce_inverted);
+		ce = &ce_inverted;
+	}
+
+	switch (ce->action) {
+	case OF_RECONFIG_ATTACH_NODE:
+	case OF_RECONFIG_DETACH_NODE:
+		memset(&rd, 0, sizeof(rd));
+		rd.dn = ce->np;
+		ret = of_reconfig_notify(ce->action, &rd);
+		break;
+	case OF_RECONFIG_ADD_PROPERTY:
+	case OF_RECONFIG_REMOVE_PROPERTY:
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		ret = of_property_notify(ce->action, ce->np, ce->prop, ce->old_prop);
+		break;
+	default:
+		pr_err("%s: invalid devicetree changeset action: %i\n", __func__,
+			(int)ce->action);
+		return;
+	}
+
+	if (ret)
+		pr_err("%s: notifier error @%s\n", __func__, ce->np->full_name);
+}
+
+static int __of_changeset_entry_apply(struct of_changeset_entry *ce)
+{
+	struct property *old_prop, **propp;
+	unsigned long flags;
+	int ret = 0;
+
+	__of_changeset_entry_dump(ce);
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	switch (ce->action) {
+	case OF_RECONFIG_ATTACH_NODE:
+		__of_attach_node(ce->np);
+		break;
+	case OF_RECONFIG_DETACH_NODE:
+		__of_detach_node(ce->np);
+		break;
+	case OF_RECONFIG_ADD_PROPERTY:
+		/* If the property is in deadprops then it must be removed */
+		for (propp = &ce->np->deadprops; *propp; propp = &(*propp)->next) {
+			if (*propp == ce->prop) {
+				*propp = ce->prop->next;
+				ce->prop->next = NULL;
+				break;
+			}
+		}
+
+		ret = __of_add_property(ce->np, ce->prop);
+		if (ret) {
+			pr_err("%s: add_property failed @%s/%s\n",
+				__func__, ce->np->full_name,
+				ce->prop->name);
+			break;
+		}
+		break;
+	case OF_RECONFIG_REMOVE_PROPERTY:
+		ret = __of_remove_property(ce->np, ce->prop);
+		if (ret) {
+			pr_err("%s: remove_property failed @%s/%s\n",
+				__func__, ce->np->full_name,
+				ce->prop->name);
+			break;
+		}
+		break;
+
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		/* If the property is in deadprops then it must be removed */
+		for (propp = &ce->np->deadprops; *propp; propp = &(*propp)->next) {
+			if (*propp == ce->prop) {
+				*propp = ce->prop->next;
+				ce->prop->next = NULL;
+				break;
+			}
+		}
+
+		ret = __of_update_property(ce->np, ce->prop, &old_prop);
+		if (ret) {
+			pr_err("%s: update_property failed @%s/%s\n",
+				__func__, ce->np->full_name,
+				ce->prop->name);
+			break;
+		}
+		break;
+	default:
+		ret = -EINVAL;
+	}
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+	if (ret)
+		return ret;
+
+	switch (ce->action) {
+	case OF_RECONFIG_ATTACH_NODE:
+		__of_attach_node_sysfs(ce->np);
+		break;
+	case OF_RECONFIG_DETACH_NODE:
+		__of_detach_node_sysfs(ce->np);
+		break;
+	case OF_RECONFIG_ADD_PROPERTY:
+		/* ignore duplicate names */
+		__of_add_property_sysfs(ce->np, ce->prop);
+		break;
+	case OF_RECONFIG_REMOVE_PROPERTY:
+		__of_remove_property_sysfs(ce->np, ce->prop);
+		break;
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		__of_update_property_sysfs(ce->np, ce->prop, ce->old_prop);
+		break;
+	}
+
+	return 0;
+}
+
+static inline int __of_changeset_entry_revert(struct of_changeset_entry *ce)
+{
+	struct of_changeset_entry ce_inverted;
+
+	__of_changeset_entry_invert(ce, &ce_inverted);
+	return __of_changeset_entry_apply(&ce_inverted);
+}
+
+/**
+ * of_changeset_init - Initialize a changeset for use
+ *
+ * @ocs:	changeset pointer
+ *
+ * Initialize a changeset structure
+ */
+void of_changeset_init(struct of_changeset *ocs)
+{
+	memset(ocs, 0, sizeof(*ocs));
+	INIT_LIST_HEAD(&ocs->entries);
+}
+
+/**
+ * of_changeset_destroy - Destroy a changeset
+ *
+ * @ocs:	changeset pointer
+ *
+ * Destroys a changeset. Note that if a changeset is applied,
+ * its changes to the tree cannot be reverted.
+ */
+void of_changeset_destroy(struct of_changeset *ocs)
+{
+	struct of_changeset_entry *ce, *cen;
+
+	list_for_each_entry_safe_reverse(ce, cen, &ocs->entries, node)
+		__of_changeset_entry_destroy(ce);
+}
+
+/**
+ * of_changeset_apply - Applies a changeset
+ *
+ * @ocs:	changeset pointer
+ *
+ * Applies a changeset to the live tree.
+ * Any side-effects of live tree state changes are applied here on
+ * sucess, like creation/destruction of devices and side-effects
+ * like creation of sysfs properties and directories.
+ * Returns 0 on success, a negative error value in case of an error.
+ * On error the partially applied effects are reverted.
+ */
+int of_changeset_apply(struct of_changeset *ocs)
+{
+	struct of_changeset_entry *ce;
+	int ret;
+
+	/* perform the rest of the work */
+	pr_debug("of_changeset: applying...\n");
+	list_for_each_entry(ce, &ocs->entries, node) {
+		ret = __of_changeset_entry_apply(ce);
+		if (ret) {
+			pr_err("%s: Error applying changeset (%d)\n", __func__, ret);
+			list_for_each_entry_continue_reverse(ce, &ocs->entries, node)
+				__of_changeset_entry_revert(ce);
+			return ret;
+		}
+	}
+	pr_debug("of_changeset: applied, emitting notifiers.\n");
+
+	/* drop the global lock while emitting notifiers */
+	mutex_unlock(&of_mutex);
+	list_for_each_entry(ce, &ocs->entries, node)
+		__of_changeset_entry_notify(ce, 0);
+	mutex_lock(&of_mutex);
+	pr_debug("of_changeset: notifiers sent.\n");
+
+	return 0;
+}
+
+/**
+ * of_changeset_revert - Reverts an applied changeset
+ *
+ * @ocs:	changeset pointer
+ *
+ * Reverts a changeset returning the state of the tree to what it
+ * was before the application.
+ * Any side-effects like creation/destruction of devices and
+ * removal of sysfs properties and directories are applied.
+ * Returns 0 on success, a negative error value in case of an error.
+ */
+int of_changeset_revert(struct of_changeset *ocs)
+{
+	struct of_changeset_entry *ce;
+	int ret;
+
+	pr_debug("of_changeset: reverting...\n");
+	list_for_each_entry_reverse(ce, &ocs->entries, node) {
+		ret = __of_changeset_entry_revert(ce);
+		if (ret) {
+			pr_err("%s: Error reverting changeset (%d)\n", __func__, ret);
+			list_for_each_entry_continue(ce, &ocs->entries, node)
+				__of_changeset_entry_apply(ce);
+			return ret;
+		}
+	}
+	pr_debug("of_changeset: reverted, emitting notifiers.\n");
+
+	/* drop the global lock while emitting notifiers */
+	mutex_unlock(&of_mutex);
+	list_for_each_entry_reverse(ce, &ocs->entries, node)
+		__of_changeset_entry_notify(ce, 1);
+	mutex_lock(&of_mutex);
+	pr_debug("of_changeset: notifiers sent.\n");
+
+	return 0;
+}
+
+/**
+ * of_changeset_action - Perform a changeset action
+ *
+ * @ocs:	changeset pointer
+ * @action:	action to perform
+ * @np:		Pointer to device node
+ * @prop:	Pointer to property
+ *
+ * On action being one of:
+ * + OF_RECONFIG_ATTACH_NODE
+ * + OF_RECONFIG_DETACH_NODE,
+ * + OF_RECONFIG_ADD_PROPERTY
+ * + OF_RECONFIG_REMOVE_PROPERTY,
+ * + OF_RECONFIG_UPDATE_PROPERTY
+ * Returns 0 on success, a negative error value in case of an error.
+ */
+int of_changeset_action(struct of_changeset *ocs, unsigned long action,
+		struct device_node *np, struct property *prop)
+{
+	struct of_changeset_entry *ce;
+
+	ce = kzalloc(sizeof(*ce), GFP_KERNEL);
+	if (!ce) {
+		pr_err("%s: Failed to allocate\n", __func__);
+		return -ENOMEM;
+	}
+	/* get a reference to the node */
+	ce->action = action;
+	ce->np = of_node_get(np);
+	ce->prop = prop;
+
+	if (action == OF_RECONFIG_UPDATE_PROPERTY && prop)
+		ce->old_prop = of_find_property(np, prop->name, NULL);
+
+	/* add it to the list */
+	list_add_tail(&ce->node, &ocs->entries);
+	return 0;
+}
diff --git a/kernel/drivers/of/fdt.c b/kernel/drivers/of/fdt.c
new file mode 100644
index 000000000..cde35c5d0
--- /dev/null
+++ b/kernel/drivers/of/fdt.c
@@ -0,0 +1,1145 @@
+/*
+ * Functions for working with the Flattened Device Tree data format
+ *
+ * Copyright 2009 Benjamin Herrenschmidt, IBM Corp
+ * benh@kernel.crashing.org
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ */
+
+#include <linux/crc32.h>
+#include <linux/kernel.h>
+#include <linux/initrd.h>
+#include <linux/memblock.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/sizes.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/libfdt.h>
+#include <linux/debugfs.h>
+#include <linux/serial_core.h>
+#include <linux/sysfs.h>
+
+#include <asm/setup.h>  /* for COMMAND_LINE_SIZE */
+#include <asm/page.h>
+
+/*
+ * of_fdt_limit_memory - limit the number of regions in the /memory node
+ * @limit: maximum entries
+ *
+ * Adjust the flattened device tree to have at most 'limit' number of
+ * memory entries in the /memory node. This function may be called
+ * any time after initial_boot_param is set.
+ */
+void of_fdt_limit_memory(int limit)
+{
+	int memory;
+	int len;
+	const void *val;
+	int nr_address_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
+	int nr_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
+	const uint32_t *addr_prop;
+	const uint32_t *size_prop;
+	int root_offset;
+	int cell_size;
+
+	root_offset = fdt_path_offset(initial_boot_params, "/");
+	if (root_offset < 0)
+		return;
+
+	addr_prop = fdt_getprop(initial_boot_params, root_offset,
+				"#address-cells", NULL);
+	if (addr_prop)
+		nr_address_cells = fdt32_to_cpu(*addr_prop);
+
+	size_prop = fdt_getprop(initial_boot_params, root_offset,
+				"#size-cells", NULL);
+	if (size_prop)
+		nr_size_cells = fdt32_to_cpu(*size_prop);
+
+	cell_size = sizeof(uint32_t)*(nr_address_cells + nr_size_cells);
+
+	memory = fdt_path_offset(initial_boot_params, "/memory");
+	if (memory > 0) {
+		val = fdt_getprop(initial_boot_params, memory, "reg", &len);
+		if (len > limit*cell_size) {
+			len = limit*cell_size;
+			pr_debug("Limiting number of entries to %d\n", limit);
+			fdt_setprop(initial_boot_params, memory, "reg", val,
+					len);
+		}
+	}
+}
+
+/**
+ * of_fdt_is_compatible - Return true if given node from the given blob has
+ * compat in its compatible list
+ * @blob: A device tree blob
+ * @node: node to test
+ * @compat: compatible string to compare with compatible list.
+ *
+ * On match, returns a non-zero value with smaller values returned for more
+ * specific compatible values.
+ */
+int of_fdt_is_compatible(const void *blob,
+		      unsigned long node, const char *compat)
+{
+	const char *cp;
+	int cplen;
+	unsigned long l, score = 0;
+
+	cp = fdt_getprop(blob, node, "compatible", &cplen);
+	if (cp == NULL)
+		return 0;
+	while (cplen > 0) {
+		score++;
+		if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
+			return score;
+		l = strlen(cp) + 1;
+		cp += l;
+		cplen -= l;
+	}
+
+	return 0;
+}
+
+/**
+ * of_fdt_is_big_endian - Return true if given node needs BE MMIO accesses
+ * @blob: A device tree blob
+ * @node: node to test
+ *
+ * Returns true if the node has a "big-endian" property, or if the kernel
+ * was compiled for BE *and* the node has a "native-endian" property.
+ * Returns false otherwise.
+ */
+bool of_fdt_is_big_endian(const void *blob, unsigned long node)
+{
+	if (fdt_getprop(blob, node, "big-endian", NULL))
+		return true;
+	if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) &&
+	    fdt_getprop(blob, node, "native-endian", NULL))
+		return true;
+	return false;
+}
+
+/**
+ * of_fdt_match - Return true if node matches a list of compatible values
+ */
+int of_fdt_match(const void *blob, unsigned long node,
+                 const char *const *compat)
+{
+	unsigned int tmp, score = 0;
+
+	if (!compat)
+		return 0;
+
+	while (*compat) {
+		tmp = of_fdt_is_compatible(blob, node, *compat);
+		if (tmp && (score == 0 || (tmp < score)))
+			score = tmp;
+		compat++;
+	}
+
+	return score;
+}
+
+static void *unflatten_dt_alloc(void **mem, unsigned long size,
+				       unsigned long align)
+{
+	void *res;
+
+	*mem = PTR_ALIGN(*mem, align);
+	res = *mem;
+	*mem += size;
+
+	return res;
+}
+
+/**
+ * unflatten_dt_node - Alloc and populate a device_node from the flat tree
+ * @blob: The parent device tree blob
+ * @mem: Memory chunk to use for allocating device nodes and properties
+ * @p: pointer to node in flat tree
+ * @dad: Parent struct device_node
+ * @fpsize: Size of the node path up at the current depth.
+ */
+static void * unflatten_dt_node(void *blob,
+				void *mem,
+				int *poffset,
+				struct device_node *dad,
+				struct device_node **nodepp,
+				unsigned long fpsize,
+				bool dryrun)
+{
+	const __be32 *p;
+	struct device_node *np;
+	struct property *pp, **prev_pp = NULL;
+	const char *pathp;
+	unsigned int l, allocl;
+	static int depth = 0;
+	int old_depth;
+	int offset;
+	int has_name = 0;
+	int new_format = 0;
+
+	pathp = fdt_get_name(blob, *poffset, &l);
+	if (!pathp)
+		return mem;
+
+	allocl = ++l;
+
+	/* version 0x10 has a more compact unit name here instead of the full
+	 * path. we accumulate the full path size using "fpsize", we'll rebuild
+	 * it later. We detect this because the first character of the name is
+	 * not '/'.
+	 */
+	if ((*pathp) != '/') {
+		new_format = 1;
+		if (fpsize == 0) {
+			/* root node: special case. fpsize accounts for path
+			 * plus terminating zero. root node only has '/', so
+			 * fpsize should be 2, but we want to avoid the first
+			 * level nodes to have two '/' so we use fpsize 1 here
+			 */
+			fpsize = 1;
+			allocl = 2;
+			l = 1;
+			pathp = "";
+		} else {
+			/* account for '/' and path size minus terminal 0
+			 * already in 'l'
+			 */
+			fpsize += l;
+			allocl = fpsize;
+		}
+	}
+
+	np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
+				__alignof__(struct device_node));
+	if (!dryrun) {
+		char *fn;
+		of_node_init(np);
+		np->full_name = fn = ((char *)np) + sizeof(*np);
+		if (new_format) {
+			/* rebuild full path for new format */
+			if (dad && dad->parent) {
+				strcpy(fn, dad->full_name);
+#ifdef DEBUG
+				if ((strlen(fn) + l + 1) != allocl) {
+					pr_debug("%s: p: %d, l: %d, a: %d\n",
+						pathp, (int)strlen(fn),
+						l, allocl);
+				}
+#endif
+				fn += strlen(fn);
+			}
+			*(fn++) = '/';
+		}
+		memcpy(fn, pathp, l);
+
+		prev_pp = &np->properties;
+		if (dad != NULL) {
+			np->parent = dad;
+			np->sibling = dad->child;
+			dad->child = np;
+		}
+	}
+	/* process properties */
+	for (offset = fdt_first_property_offset(blob, *poffset);
+	     (offset >= 0);
+	     (offset = fdt_next_property_offset(blob, offset))) {
+		const char *pname;
+		u32 sz;
+
+		if (!(p = fdt_getprop_by_offset(blob, offset, &pname, &sz))) {
+			offset = -FDT_ERR_INTERNAL;
+			break;
+		}
+
+		if (pname == NULL) {
+			pr_info("Can't find property name in list !\n");
+			break;
+		}
+		if (strcmp(pname, "name") == 0)
+			has_name = 1;
+		pp = unflatten_dt_alloc(&mem, sizeof(struct property),
+					__alignof__(struct property));
+		if (!dryrun) {
+			/* We accept flattened tree phandles either in
+			 * ePAPR-style "phandle" properties, or the
+			 * legacy "linux,phandle" properties.  If both
+			 * appear and have different values, things
+			 * will get weird.  Don't do that. */
+			if ((strcmp(pname, "phandle") == 0) ||
+			    (strcmp(pname, "linux,phandle") == 0)) {
+				if (np->phandle == 0)
+					np->phandle = be32_to_cpup(p);
+			}
+			/* And we process the "ibm,phandle" property
+			 * used in pSeries dynamic device tree
+			 * stuff */
+			if (strcmp(pname, "ibm,phandle") == 0)
+				np->phandle = be32_to_cpup(p);
+			pp->name = (char *)pname;
+			pp->length = sz;
+			pp->value = (__be32 *)p;
+			*prev_pp = pp;
+			prev_pp = &pp->next;
+		}
+	}
+	/* with version 0x10 we may not have the name property, recreate
+	 * it here from the unit name if absent
+	 */
+	if (!has_name) {
+		const char *p1 = pathp, *ps = pathp, *pa = NULL;
+		int sz;
+
+		while (*p1) {
+			if ((*p1) == '@')
+				pa = p1;
+			if ((*p1) == '/')
+				ps = p1 + 1;
+			p1++;
+		}
+		if (pa < ps)
+			pa = p1;
+		sz = (pa - ps) + 1;
+		pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
+					__alignof__(struct property));
+		if (!dryrun) {
+			pp->name = "name";
+			pp->length = sz;
+			pp->value = pp + 1;
+			*prev_pp = pp;
+			prev_pp = &pp->next;
+			memcpy(pp->value, ps, sz - 1);
+			((char *)pp->value)[sz - 1] = 0;
+			pr_debug("fixed up name for %s -> %s\n", pathp,
+				(char *)pp->value);
+		}
+	}
+	if (!dryrun) {
+		*prev_pp = NULL;
+		np->name = of_get_property(np, "name", NULL);
+		np->type = of_get_property(np, "device_type", NULL);
+
+		if (!np->name)
+			np->name = "<NULL>";
+		if (!np->type)
+			np->type = "<NULL>";
+	}
+
+	old_depth = depth;
+	*poffset = fdt_next_node(blob, *poffset, &depth);
+	if (depth < 0)
+		depth = 0;
+	while (*poffset > 0 && depth > old_depth)
+		mem = unflatten_dt_node(blob, mem, poffset, np, NULL,
+					fpsize, dryrun);
+
+	if (*poffset < 0 && *poffset != -FDT_ERR_NOTFOUND)
+		pr_err("unflatten: error %d processing FDT\n", *poffset);
+
+	/*
+	 * Reverse the child list. Some drivers assumes node order matches .dts
+	 * node order
+	 */
+	if (!dryrun && np->child) {
+		struct device_node *child = np->child;
+		np->child = NULL;
+		while (child) {
+			struct device_node *next = child->sibling;
+			child->sibling = np->child;
+			np->child = child;
+			child = next;
+		}
+	}
+
+	if (nodepp)
+		*nodepp = np;
+
+	return mem;
+}
+
+/**
+ * __unflatten_device_tree - create tree of device_nodes from flat blob
+ *
+ * unflattens a device-tree, creating the
+ * tree of struct device_node. It also fills the "name" and "type"
+ * pointers of the nodes so the normal device-tree walking functions
+ * can be used.
+ * @blob: The blob to expand
+ * @mynodes: The device_node tree created by the call
+ * @dt_alloc: An allocator that provides a virtual address to memory
+ * for the resulting tree
+ */
+static void __unflatten_device_tree(void *blob,
+			     struct device_node **mynodes,
+			     void * (*dt_alloc)(u64 size, u64 align))
+{
+	unsigned long size;
+	int start;
+	void *mem;
+
+	pr_debug(" -> unflatten_device_tree()\n");
+
+	if (!blob) {
+		pr_debug("No device tree pointer\n");
+		return;
+	}
+
+	pr_debug("Unflattening device tree:\n");
+	pr_debug("magic: %08x\n", fdt_magic(blob));
+	pr_debug("size: %08x\n", fdt_totalsize(blob));
+	pr_debug("version: %08x\n", fdt_version(blob));
+
+	if (fdt_check_header(blob)) {
+		pr_err("Invalid device tree blob header\n");
+		return;
+	}
+
+	/* First pass, scan for size */
+	start = 0;
+	size = (unsigned long)unflatten_dt_node(blob, NULL, &start, NULL, NULL, 0, true);
+	size = ALIGN(size, 4);
+
+	pr_debug("  size is %lx, allocating...\n", size);
+
+	/* Allocate memory for the expanded device tree */
+	mem = dt_alloc(size + 4, __alignof__(struct device_node));
+	memset(mem, 0, size);
+
+	*(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef);
+
+	pr_debug("  unflattening %p...\n", mem);
+
+	/* Second pass, do actual unflattening */
+	start = 0;
+	unflatten_dt_node(blob, mem, &start, NULL, mynodes, 0, false);
+	if (be32_to_cpup(mem + size) != 0xdeadbeef)
+		pr_warning("End of tree marker overwritten: %08x\n",
+			   be32_to_cpup(mem + size));
+
+	pr_debug(" <- unflatten_device_tree()\n");
+}
+
+static void *kernel_tree_alloc(u64 size, u64 align)
+{
+	return kzalloc(size, GFP_KERNEL);
+}
+
+/**
+ * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
+ *
+ * unflattens the device-tree passed by the firmware, creating the
+ * tree of struct device_node. It also fills the "name" and "type"
+ * pointers of the nodes so the normal device-tree walking functions
+ * can be used.
+ */
+void of_fdt_unflatten_tree(unsigned long *blob,
+			struct device_node **mynodes)
+{
+	__unflatten_device_tree(blob, mynodes, &kernel_tree_alloc);
+}
+EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
+
+/* Everything below here references initial_boot_params directly. */
+int __initdata dt_root_addr_cells;
+int __initdata dt_root_size_cells;
+
+void *initial_boot_params;
+
+#ifdef CONFIG_OF_EARLY_FLATTREE
+
+static u32 of_fdt_crc32;
+
+/**
+ * res_mem_reserve_reg() - reserve all memory described in 'reg' property
+ */
+static int __init __reserved_mem_reserve_reg(unsigned long node,
+					     const char *uname)
+{
+	int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
+	phys_addr_t base, size;
+	int len;
+	const __be32 *prop;
+	int nomap, first = 1;
+
+	prop = of_get_flat_dt_prop(node, "reg", &len);
+	if (!prop)
+		return -ENOENT;
+
+	if (len && len % t_len != 0) {
+		pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
+		       uname);
+		return -EINVAL;
+	}
+
+	nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
+
+	while (len >= t_len) {
+		base = dt_mem_next_cell(dt_root_addr_cells, &prop);
+		size = dt_mem_next_cell(dt_root_size_cells, &prop);
+
+		if (size &&
+		    early_init_dt_reserve_memory_arch(base, size, nomap) == 0)
+			pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %ld MiB\n",
+				uname, &base, (unsigned long)size / SZ_1M);
+		else
+			pr_info("Reserved memory: failed to reserve memory for node '%s': base %pa, size %ld MiB\n",
+				uname, &base, (unsigned long)size / SZ_1M);
+
+		len -= t_len;
+		if (first) {
+			fdt_reserved_mem_save_node(node, uname, base, size);
+			first = 0;
+		}
+	}
+	return 0;
+}
+
+/**
+ * __reserved_mem_check_root() - check if #size-cells, #address-cells provided
+ * in /reserved-memory matches the values supported by the current implementation,
+ * also check if ranges property has been provided
+ */
+static int __init __reserved_mem_check_root(unsigned long node)
+{
+	const __be32 *prop;
+
+	prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
+	if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
+		return -EINVAL;
+
+	prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
+	if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
+		return -EINVAL;
+
+	prop = of_get_flat_dt_prop(node, "ranges", NULL);
+	if (!prop)
+		return -EINVAL;
+	return 0;
+}
+
+/**
+ * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
+ */
+static int __init __fdt_scan_reserved_mem(unsigned long node, const char *uname,
+					  int depth, void *data)
+{
+	static int found;
+	const char *status;
+	int err;
+
+	if (!found && depth == 1 && strcmp(uname, "reserved-memory") == 0) {
+		if (__reserved_mem_check_root(node) != 0) {
+			pr_err("Reserved memory: unsupported node format, ignoring\n");
+			/* break scan */
+			return 1;
+		}
+		found = 1;
+		/* scan next node */
+		return 0;
+	} else if (!found) {
+		/* scan next node */
+		return 0;
+	} else if (found && depth < 2) {
+		/* scanning of /reserved-memory has been finished */
+		return 1;
+	}
+
+	status = of_get_flat_dt_prop(node, "status", NULL);
+	if (status && strcmp(status, "okay") != 0 && strcmp(status, "ok") != 0)
+		return 0;
+
+	err = __reserved_mem_reserve_reg(node, uname);
+	if (err == -ENOENT && of_get_flat_dt_prop(node, "size", NULL))
+		fdt_reserved_mem_save_node(node, uname, 0, 0);
+
+	/* scan next node */
+	return 0;
+}
+
+/**
+ * early_init_fdt_scan_reserved_mem() - create reserved memory regions
+ *
+ * This function grabs memory from early allocator for device exclusive use
+ * defined in device tree structures. It should be called by arch specific code
+ * once the early allocator (i.e. memblock) has been fully activated.
+ */
+void __init early_init_fdt_scan_reserved_mem(void)
+{
+	int n;
+	u64 base, size;
+
+	if (!initial_boot_params)
+		return;
+
+	/* Reserve the dtb region */
+	early_init_dt_reserve_memory_arch(__pa(initial_boot_params),
+					  fdt_totalsize(initial_boot_params),
+					  0);
+
+	/* Process header /memreserve/ fields */
+	for (n = 0; ; n++) {
+		fdt_get_mem_rsv(initial_boot_params, n, &base, &size);
+		if (!size)
+			break;
+		early_init_dt_reserve_memory_arch(base, size, 0);
+	}
+
+	of_scan_flat_dt(__fdt_scan_reserved_mem, NULL);
+	fdt_init_reserved_mem();
+}
+
+/**
+ * of_scan_flat_dt - scan flattened tree blob and call callback on each.
+ * @it: callback function
+ * @data: context data pointer
+ *
+ * This function is used to scan the flattened device-tree, it is
+ * used to extract the memory information at boot before we can
+ * unflatten the tree
+ */
+int __init of_scan_flat_dt(int (*it)(unsigned long node,
+				     const char *uname, int depth,
+				     void *data),
+			   void *data)
+{
+	const void *blob = initial_boot_params;
+	const char *pathp;
+	int offset, rc = 0, depth = -1;
+
+        for (offset = fdt_next_node(blob, -1, &depth);
+             offset >= 0 && depth >= 0 && !rc;
+             offset = fdt_next_node(blob, offset, &depth)) {
+
+		pathp = fdt_get_name(blob, offset, NULL);
+		if (*pathp == '/')
+			pathp = kbasename(pathp);
+		rc = it(offset, pathp, depth, data);
+	}
+	return rc;
+}
+
+/**
+ * of_get_flat_dt_root - find the root node in the flat blob
+ */
+unsigned long __init of_get_flat_dt_root(void)
+{
+	return 0;
+}
+
+/**
+ * of_get_flat_dt_size - Return the total size of the FDT
+ */
+int __init of_get_flat_dt_size(void)
+{
+	return fdt_totalsize(initial_boot_params);
+}
+
+/**
+ * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
+ *
+ * This function can be used within scan_flattened_dt callback to get
+ * access to properties
+ */
+const void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
+				       int *size)
+{
+	return fdt_getprop(initial_boot_params, node, name, size);
+}
+
+/**
+ * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
+ * @node: node to test
+ * @compat: compatible string to compare with compatible list.
+ */
+int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
+{
+	return of_fdt_is_compatible(initial_boot_params, node, compat);
+}
+
+/**
+ * of_flat_dt_match - Return true if node matches a list of compatible values
+ */
+int __init of_flat_dt_match(unsigned long node, const char *const *compat)
+{
+	return of_fdt_match(initial_boot_params, node, compat);
+}
+
+struct fdt_scan_status {
+	const char *name;
+	int namelen;
+	int depth;
+	int found;
+	int (*iterator)(unsigned long node, const char *uname, int depth, void *data);
+	void *data;
+};
+
+const char * __init of_flat_dt_get_machine_name(void)
+{
+	const char *name;
+	unsigned long dt_root = of_get_flat_dt_root();
+
+	name = of_get_flat_dt_prop(dt_root, "model", NULL);
+	if (!name)
+		name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
+	return name;
+}
+
+/**
+ * of_flat_dt_match_machine - Iterate match tables to find matching machine.
+ *
+ * @default_match: A machine specific ptr to return in case of no match.
+ * @get_next_compat: callback function to return next compatible match table.
+ *
+ * Iterate through machine match tables to find the best match for the machine
+ * compatible string in the FDT.
+ */
+const void * __init of_flat_dt_match_machine(const void *default_match,
+		const void * (*get_next_compat)(const char * const**))
+{
+	const void *data = NULL;
+	const void *best_data = default_match;
+	const char *const *compat;
+	unsigned long dt_root;
+	unsigned int best_score = ~1, score = 0;
+
+	dt_root = of_get_flat_dt_root();
+	while ((data = get_next_compat(&compat))) {
+		score = of_flat_dt_match(dt_root, compat);
+		if (score > 0 && score < best_score) {
+			best_data = data;
+			best_score = score;
+		}
+	}
+	if (!best_data) {
+		const char *prop;
+		int size;
+
+		pr_err("\n unrecognized device tree list:\n[ ");
+
+		prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
+		if (prop) {
+			while (size > 0) {
+				printk("'%s' ", prop);
+				size -= strlen(prop) + 1;
+				prop += strlen(prop) + 1;
+			}
+		}
+		printk("]\n\n");
+		return NULL;
+	}
+
+	pr_info("Machine model: %s\n", of_flat_dt_get_machine_name());
+
+	return best_data;
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+/**
+ * early_init_dt_check_for_initrd - Decode initrd location from flat tree
+ * @node: reference to node containing initrd location ('chosen')
+ */
+static void __init early_init_dt_check_for_initrd(unsigned long node)
+{
+	u64 start, end;
+	int len;
+	const __be32 *prop;
+
+	pr_debug("Looking for initrd properties... ");
+
+	prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
+	if (!prop)
+		return;
+	start = of_read_number(prop, len/4);
+
+	prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
+	if (!prop)
+		return;
+	end = of_read_number(prop, len/4);
+
+	initrd_start = (unsigned long)__va(start);
+	initrd_end = (unsigned long)__va(end);
+	initrd_below_start_ok = 1;
+
+	pr_debug("initrd_start=0x%llx  initrd_end=0x%llx\n",
+		 (unsigned long long)start, (unsigned long long)end);
+}
+#else
+static inline void early_init_dt_check_for_initrd(unsigned long node)
+{
+}
+#endif /* CONFIG_BLK_DEV_INITRD */
+
+#ifdef CONFIG_SERIAL_EARLYCON
+extern struct of_device_id __earlycon_of_table[];
+
+static int __init early_init_dt_scan_chosen_serial(void)
+{
+	int offset;
+	const char *p;
+	int l;
+	const struct of_device_id *match = __earlycon_of_table;
+	const void *fdt = initial_boot_params;
+
+	offset = fdt_path_offset(fdt, "/chosen");
+	if (offset < 0)
+		offset = fdt_path_offset(fdt, "/chosen@0");
+	if (offset < 0)
+		return -ENOENT;
+
+	p = fdt_getprop(fdt, offset, "stdout-path", &l);
+	if (!p)
+		p = fdt_getprop(fdt, offset, "linux,stdout-path", &l);
+	if (!p || !l)
+		return -ENOENT;
+
+	/* Get the node specified by stdout-path */
+	offset = fdt_path_offset(fdt, p);
+	if (offset < 0)
+		return -ENODEV;
+
+	while (match->compatible[0]) {
+		unsigned long addr;
+		if (fdt_node_check_compatible(fdt, offset, match->compatible)) {
+			match++;
+			continue;
+		}
+
+		addr = fdt_translate_address(fdt, offset);
+		if (!addr)
+			return -ENXIO;
+
+		of_setup_earlycon(addr, match->data);
+		return 0;
+	}
+	return -ENODEV;
+}
+
+static int __init setup_of_earlycon(char *buf)
+{
+	if (buf)
+		return 0;
+
+	return early_init_dt_scan_chosen_serial();
+}
+early_param("earlycon", setup_of_earlycon);
+#endif
+
+/**
+ * early_init_dt_scan_root - fetch the top level address and size cells
+ */
+int __init early_init_dt_scan_root(unsigned long node, const char *uname,
+				   int depth, void *data)
+{
+	const __be32 *prop;
+
+	if (depth != 0)
+		return 0;
+
+	dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
+	dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
+
+	prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
+	if (prop)
+		dt_root_size_cells = be32_to_cpup(prop);
+	pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
+
+	prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
+	if (prop)
+		dt_root_addr_cells = be32_to_cpup(prop);
+	pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
+
+	/* break now */
+	return 1;
+}
+
+u64 __init dt_mem_next_cell(int s, const __be32 **cellp)
+{
+	const __be32 *p = *cellp;
+
+	*cellp = p + s;
+	return of_read_number(p, s);
+}
+
+/**
+ * early_init_dt_scan_memory - Look for an parse memory nodes
+ */
+int __init early_init_dt_scan_memory(unsigned long node, const char *uname,
+				     int depth, void *data)
+{
+	const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
+	const __be32 *reg, *endp;
+	int l;
+
+	/* We are scanning "memory" nodes only */
+	if (type == NULL) {
+		/*
+		 * The longtrail doesn't have a device_type on the
+		 * /memory node, so look for the node called /memory@0.
+		 */
+		if (!IS_ENABLED(CONFIG_PPC32) || depth != 1 || strcmp(uname, "memory@0") != 0)
+			return 0;
+	} else if (strcmp(type, "memory") != 0)
+		return 0;
+
+	reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
+	if (reg == NULL)
+		reg = of_get_flat_dt_prop(node, "reg", &l);
+	if (reg == NULL)
+		return 0;
+
+	endp = reg + (l / sizeof(__be32));
+
+	pr_debug("memory scan node %s, reg size %d,\n", uname, l);
+
+	while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
+		u64 base, size;
+
+		base = dt_mem_next_cell(dt_root_addr_cells, &reg);
+		size = dt_mem_next_cell(dt_root_size_cells, &reg);
+
+		if (size == 0)
+			continue;
+		pr_debug(" - %llx ,  %llx\n", (unsigned long long)base,
+		    (unsigned long long)size);
+
+		early_init_dt_add_memory_arch(base, size);
+	}
+
+	return 0;
+}
+
+int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
+				     int depth, void *data)
+{
+	int l;
+	const char *p;
+
+	pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
+
+	if (depth != 1 || !data ||
+	    (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
+		return 0;
+
+	early_init_dt_check_for_initrd(node);
+
+	/* Retrieve command line */
+	p = of_get_flat_dt_prop(node, "bootargs", &l);
+	if (p != NULL && l > 0)
+		strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE));
+
+	/*
+	 * CONFIG_CMDLINE is meant to be a default in case nothing else
+	 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
+	 * is set in which case we override whatever was found earlier.
+	 */
+#ifdef CONFIG_CMDLINE
+#ifndef CONFIG_CMDLINE_FORCE
+	if (!((char *)data)[0])
+#endif
+		strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
+#endif /* CONFIG_CMDLINE */
+
+	pr_debug("Command line is: %s\n", (char*)data);
+
+	/* break now */
+	return 1;
+}
+
+#ifdef CONFIG_HAVE_MEMBLOCK
+#define MAX_PHYS_ADDR	((phys_addr_t)~0)
+
+void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
+{
+	const u64 phys_offset = __pa(PAGE_OFFSET);
+
+	if (!PAGE_ALIGNED(base)) {
+		if (size < PAGE_SIZE - (base & ~PAGE_MASK)) {
+			pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
+				base, base + size);
+			return;
+		}
+		size -= PAGE_SIZE - (base & ~PAGE_MASK);
+		base = PAGE_ALIGN(base);
+	}
+	size &= PAGE_MASK;
+
+	if (base > MAX_PHYS_ADDR) {
+		pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
+				base, base + size);
+		return;
+	}
+
+	if (base + size - 1 > MAX_PHYS_ADDR) {
+		pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
+				((u64)MAX_PHYS_ADDR) + 1, base + size);
+		size = MAX_PHYS_ADDR - base + 1;
+	}
+
+	if (base + size < phys_offset) {
+		pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
+			   base, base + size);
+		return;
+	}
+	if (base < phys_offset) {
+		pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
+			   base, phys_offset);
+		size -= phys_offset - base;
+		base = phys_offset;
+	}
+	memblock_add(base, size);
+}
+
+int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
+					phys_addr_t size, bool nomap)
+{
+	if (nomap)
+		return memblock_remove(base, size);
+	return memblock_reserve(base, size);
+}
+
+/*
+ * called from unflatten_device_tree() to bootstrap devicetree itself
+ * Architectures can override this definition if memblock isn't used
+ */
+void * __init __weak early_init_dt_alloc_memory_arch(u64 size, u64 align)
+{
+	return __va(memblock_alloc(size, align));
+}
+#else
+int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
+					phys_addr_t size, bool nomap)
+{
+	pr_err("Reserved memory not supported, ignoring range 0x%pa - 0x%pa%s\n",
+		  &base, &size, nomap ? " (nomap)" : "");
+	return -ENOSYS;
+}
+#endif
+
+bool __init early_init_dt_verify(void *params)
+{
+	if (!params)
+		return false;
+
+	/* check device tree validity */
+	if (fdt_check_header(params))
+		return false;
+
+	/* Setup flat device-tree pointer */
+	initial_boot_params = params;
+	of_fdt_crc32 = crc32_be(~0, initial_boot_params,
+				fdt_totalsize(initial_boot_params));
+	return true;
+}
+
+
+void __init early_init_dt_scan_nodes(void)
+{
+	/* Retrieve various information from the /chosen node */
+	of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
+
+	/* Initialize {size,address}-cells info */
+	of_scan_flat_dt(early_init_dt_scan_root, NULL);
+
+	/* Setup memory, calling early_init_dt_add_memory_arch */
+	of_scan_flat_dt(early_init_dt_scan_memory, NULL);
+}
+
+bool __init early_init_dt_scan(void *params)
+{
+	bool status;
+
+	status = early_init_dt_verify(params);
+	if (!status)
+		return false;
+
+	early_init_dt_scan_nodes();
+	return true;
+}
+
+/**
+ * unflatten_device_tree - create tree of device_nodes from flat blob
+ *
+ * unflattens the device-tree passed by the firmware, creating the
+ * tree of struct device_node. It also fills the "name" and "type"
+ * pointers of the nodes so the normal device-tree walking functions
+ * can be used.
+ */
+void __init unflatten_device_tree(void)
+{
+	__unflatten_device_tree(initial_boot_params, &of_root,
+				early_init_dt_alloc_memory_arch);
+
+	/* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
+	of_alias_scan(early_init_dt_alloc_memory_arch);
+}
+
+/**
+ * unflatten_and_copy_device_tree - copy and create tree of device_nodes from flat blob
+ *
+ * Copies and unflattens the device-tree passed by the firmware, creating the
+ * tree of struct device_node. It also fills the "name" and "type"
+ * pointers of the nodes so the normal device-tree walking functions
+ * can be used. This should only be used when the FDT memory has not been
+ * reserved such is the case when the FDT is built-in to the kernel init
+ * section. If the FDT memory is reserved already then unflatten_device_tree
+ * should be used instead.
+ */
+void __init unflatten_and_copy_device_tree(void)
+{
+	int size;
+	void *dt;
+
+	if (!initial_boot_params) {
+		pr_warn("No valid device tree found, continuing without\n");
+		return;
+	}
+
+	size = fdt_totalsize(initial_boot_params);
+	dt = early_init_dt_alloc_memory_arch(size,
+					     roundup_pow_of_two(FDT_V17_SIZE));
+
+	if (dt) {
+		memcpy(dt, initial_boot_params, size);
+		initial_boot_params = dt;
+	}
+	unflatten_device_tree();
+}
+
+#ifdef CONFIG_SYSFS
+static ssize_t of_fdt_raw_read(struct file *filp, struct kobject *kobj,
+			       struct bin_attribute *bin_attr,
+			       char *buf, loff_t off, size_t count)
+{
+	memcpy(buf, initial_boot_params + off, count);
+	return count;
+}
+
+static int __init of_fdt_raw_init(void)
+{
+	static struct bin_attribute of_fdt_raw_attr =
+		__BIN_ATTR(fdt, S_IRUSR, of_fdt_raw_read, NULL, 0);
+
+	if (!initial_boot_params)
+		return 0;
+
+	if (of_fdt_crc32 != crc32_be(~0, initial_boot_params,
+				     fdt_totalsize(initial_boot_params))) {
+		pr_warn("fdt: not creating '/sys/firmware/fdt': CRC check failed\n");
+		return 0;
+	}
+	of_fdt_raw_attr.size = fdt_totalsize(initial_boot_params);
+	return sysfs_create_bin_file(firmware_kobj, &of_fdt_raw_attr);
+}
+late_initcall(of_fdt_raw_init);
+#endif
+
+#endif /* CONFIG_OF_EARLY_FLATTREE */
diff --git a/kernel/drivers/of/fdt_address.c b/kernel/drivers/of/fdt_address.c
new file mode 100644
index 000000000..8d3dc6fbd
--- /dev/null
+++ b/kernel/drivers/of/fdt_address.c
@@ -0,0 +1,241 @@
+/*
+ * FDT Address translation based on u-boot fdt_support.c which in turn was
+ * based on the kernel unflattened DT address translation code.
+ *
+ * (C) Copyright 2007
+ * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com
+ *
+ * Copyright 2010-2011 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ */
+#include <linux/kernel.h>
+#include <linux/libfdt.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/sizes.h>
+
+/* Max address size we deal with */
+#define OF_MAX_ADDR_CELLS	4
+#define OF_CHECK_COUNTS(na, ns)	((na) > 0 && (na) <= OF_MAX_ADDR_CELLS && \
+			(ns) > 0)
+
+/* Debug utility */
+#ifdef DEBUG
+static void __init of_dump_addr(const char *s, const __be32 *addr, int na)
+{
+	pr_debug("%s", s);
+	while(na--)
+		pr_cont(" %08x", *(addr++));
+	pr_debug("\n");
+}
+#else
+static void __init of_dump_addr(const char *s, const __be32 *addr, int na) { }
+#endif
+
+/* Callbacks for bus specific translators */
+struct of_bus {
+	void		(*count_cells)(const void *blob, int parentoffset,
+				int *addrc, int *sizec);
+	u64		(*map)(__be32 *addr, const __be32 *range,
+				int na, int ns, int pna);
+	int		(*translate)(__be32 *addr, u64 offset, int na);
+};
+
+/* Default translator (generic bus) */
+static void __init fdt_bus_default_count_cells(const void *blob, int parentoffset,
+					       int *addrc, int *sizec)
+{
+	const __be32 *prop;
+
+	if (addrc) {
+		prop = fdt_getprop(blob, parentoffset, "#address-cells", NULL);
+		if (prop)
+			*addrc = be32_to_cpup(prop);
+		else
+			*addrc = dt_root_addr_cells;
+	}
+
+	if (sizec) {
+		prop = fdt_getprop(blob, parentoffset, "#size-cells", NULL);
+		if (prop)
+			*sizec = be32_to_cpup(prop);
+		else
+			*sizec = dt_root_size_cells;
+	}
+}
+
+static u64 __init fdt_bus_default_map(__be32 *addr, const __be32 *range,
+				      int na, int ns, int pna)
+{
+	u64 cp, s, da;
+
+	cp = of_read_number(range, na);
+	s  = of_read_number(range + na + pna, ns);
+	da = of_read_number(addr, na);
+
+	pr_debug("FDT: default map, cp=%llx, s=%llx, da=%llx\n",
+	    cp, s, da);
+
+	if (da < cp || da >= (cp + s))
+		return OF_BAD_ADDR;
+	return da - cp;
+}
+
+static int __init fdt_bus_default_translate(__be32 *addr, u64 offset, int na)
+{
+	u64 a = of_read_number(addr, na);
+	memset(addr, 0, na * 4);
+	a += offset;
+	if (na > 1)
+		addr[na - 2] = cpu_to_fdt32(a >> 32);
+	addr[na - 1] = cpu_to_fdt32(a & 0xffffffffu);
+
+	return 0;
+}
+
+/* Array of bus specific translators */
+static const struct of_bus of_busses[] __initconst = {
+	/* Default */
+	{
+		.count_cells = fdt_bus_default_count_cells,
+		.map = fdt_bus_default_map,
+		.translate = fdt_bus_default_translate,
+	},
+};
+
+static int __init fdt_translate_one(const void *blob, int parent,
+				    const struct of_bus *bus,
+				    const struct of_bus *pbus, __be32 *addr,
+				    int na, int ns, int pna, const char *rprop)
+{
+	const __be32 *ranges;
+	int rlen;
+	int rone;
+	u64 offset = OF_BAD_ADDR;
+
+	ranges = fdt_getprop(blob, parent, rprop, &rlen);
+	if (!ranges)
+		return 1;
+	if (rlen == 0) {
+		offset = of_read_number(addr, na);
+		memset(addr, 0, pna * 4);
+		pr_debug("FDT: empty ranges, 1:1 translation\n");
+		goto finish;
+	}
+
+	pr_debug("FDT: walking ranges...\n");
+
+	/* Now walk through the ranges */
+	rlen /= 4;
+	rone = na + pna + ns;
+	for (; rlen >= rone; rlen -= rone, ranges += rone) {
+		offset = bus->map(addr, ranges, na, ns, pna);
+		if (offset != OF_BAD_ADDR)
+			break;
+	}
+	if (offset == OF_BAD_ADDR) {
+		pr_debug("FDT: not found !\n");
+		return 1;
+	}
+	memcpy(addr, ranges + na, 4 * pna);
+
+ finish:
+	of_dump_addr("FDT: parent translation for:", addr, pna);
+	pr_debug("FDT: with offset: %llx\n", offset);
+
+	/* Translate it into parent bus space */
+	return pbus->translate(addr, offset, pna);
+}
+
+/*
+ * Translate an address from the device-tree into a CPU physical address,
+ * this walks up the tree and applies the various bus mappings on the
+ * way.
+ *
+ * Note: We consider that crossing any level with #size-cells == 0 to mean
+ * that translation is impossible (that is we are not dealing with a value
+ * that can be mapped to a cpu physical address). This is not really specified
+ * that way, but this is traditionally the way IBM at least do things
+ */
+u64 __init fdt_translate_address(const void *blob, int node_offset)
+{
+	int parent, len;
+	const struct of_bus *bus, *pbus;
+	const __be32 *reg;
+	__be32 addr[OF_MAX_ADDR_CELLS];
+	int na, ns, pna, pns;
+	u64 result = OF_BAD_ADDR;
+
+	pr_debug("FDT: ** translation for device %s **\n",
+		 fdt_get_name(blob, node_offset, NULL));
+
+	reg = fdt_getprop(blob, node_offset, "reg", &len);
+	if (!reg) {
+		pr_err("FDT: warning: device tree node '%s' has no address.\n",
+			fdt_get_name(blob, node_offset, NULL));
+		goto bail;
+	}
+
+	/* Get parent & match bus type */
+	parent = fdt_parent_offset(blob, node_offset);
+	if (parent < 0)
+		goto bail;
+	bus = &of_busses[0];
+
+	/* Cound address cells & copy address locally */
+	bus->count_cells(blob, parent, &na, &ns);
+	if (!OF_CHECK_COUNTS(na, ns)) {
+		pr_err("FDT: Bad cell count for %s\n",
+		       fdt_get_name(blob, node_offset, NULL));
+		goto bail;
+	}
+	memcpy(addr, reg, na * 4);
+
+	pr_debug("FDT: bus (na=%d, ns=%d) on %s\n",
+		 na, ns, fdt_get_name(blob, parent, NULL));
+	of_dump_addr("OF: translating address:", addr, na);
+
+	/* Translate */
+	for (;;) {
+		/* Switch to parent bus */
+		node_offset = parent;
+		parent = fdt_parent_offset(blob, node_offset);
+
+		/* If root, we have finished */
+		if (parent < 0) {
+			pr_debug("FDT: reached root node\n");
+			result = of_read_number(addr, na);
+			break;
+		}
+
+		/* Get new parent bus and counts */
+		pbus = &of_busses[0];
+		pbus->count_cells(blob, parent, &pna, &pns);
+		if (!OF_CHECK_COUNTS(pna, pns)) {
+			pr_err("FDT: Bad cell count for %s\n",
+				fdt_get_name(blob, node_offset, NULL));
+			break;
+		}
+
+		pr_debug("FDT: parent bus (na=%d, ns=%d) on %s\n",
+			 pna, pns, fdt_get_name(blob, parent, NULL));
+
+		/* Apply bus translation */
+		if (fdt_translate_one(blob, node_offset, bus, pbus,
+					addr, na, ns, pna, "ranges"))
+			break;
+
+		/* Complete the move up one level */
+		na = pna;
+		ns = pns;
+		bus = pbus;
+
+		of_dump_addr("FDT: one level translation:", addr, na);
+	}
+ bail:
+	return result;
+}
diff --git a/kernel/drivers/of/irq.c b/kernel/drivers/of/irq.c
new file mode 100644
index 000000000..1a7980692
--- /dev/null
+++ b/kernel/drivers/of/irq.c
@@ -0,0 +1,579 @@
+/*
+ *  Derived from arch/i386/kernel/irq.c
+ *    Copyright (C) 1992 Linus Torvalds
+ *  Adapted from arch/i386 by Gary Thomas
+ *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *  Updated and modified by Cort Dougan <cort@fsmlabs.com>
+ *    Copyright (C) 1996-2001 Cort Dougan
+ *  Adapted for Power Macintosh by Paul Mackerras
+ *    Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * This file contains the code used to make IRQ descriptions in the
+ * device tree to actual irq numbers on an interrupt controller
+ * driver.
+ */
+
+#include <linux/errno.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+
+/**
+ * irq_of_parse_and_map - Parse and map an interrupt into linux virq space
+ * @dev: Device node of the device whose interrupt is to be mapped
+ * @index: Index of the interrupt to map
+ *
+ * This function is a wrapper that chains of_irq_parse_one() and
+ * irq_create_of_mapping() to make things easier to callers
+ */
+unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
+{
+	struct of_phandle_args oirq;
+
+	if (of_irq_parse_one(dev, index, &oirq))
+		return 0;
+
+	return irq_create_of_mapping(&oirq);
+}
+EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
+
+/**
+ * of_irq_find_parent - Given a device node, find its interrupt parent node
+ * @child: pointer to device node
+ *
+ * Returns a pointer to the interrupt parent node, or NULL if the interrupt
+ * parent could not be determined.
+ */
+struct device_node *of_irq_find_parent(struct device_node *child)
+{
+	struct device_node *p;
+	const __be32 *parp;
+
+	if (!of_node_get(child))
+		return NULL;
+
+	do {
+		parp = of_get_property(child, "interrupt-parent", NULL);
+		if (parp == NULL)
+			p = of_get_parent(child);
+		else {
+			if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
+				p = of_node_get(of_irq_dflt_pic);
+			else
+				p = of_find_node_by_phandle(be32_to_cpup(parp));
+		}
+		of_node_put(child);
+		child = p;
+	} while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL);
+
+	return p;
+}
+
+/**
+ * of_irq_parse_raw - Low level interrupt tree parsing
+ * @parent:	the device interrupt parent
+ * @addr:	address specifier (start of "reg" property of the device) in be32 format
+ * @out_irq:	structure of_irq updated by this function
+ *
+ * Returns 0 on success and a negative number on error
+ *
+ * This function is a low-level interrupt tree walking function. It
+ * can be used to do a partial walk with synthetized reg and interrupts
+ * properties, for example when resolving PCI interrupts when no device
+ * node exist for the parent. It takes an interrupt specifier structure as
+ * input, walks the tree looking for any interrupt-map properties, translates
+ * the specifier for each map, and then returns the translated map.
+ */
+int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq)
+{
+	struct device_node *ipar, *tnode, *old = NULL, *newpar = NULL;
+	__be32 initial_match_array[MAX_PHANDLE_ARGS];
+	const __be32 *match_array = initial_match_array;
+	const __be32 *tmp, *imap, *imask, dummy_imask[] = { [0 ... MAX_PHANDLE_ARGS] = ~0 };
+	u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
+	int imaplen, match, i;
+
+#ifdef DEBUG
+	of_print_phandle_args("of_irq_parse_raw: ", out_irq);
+#endif
+
+	ipar = of_node_get(out_irq->np);
+
+	/* First get the #interrupt-cells property of the current cursor
+	 * that tells us how to interpret the passed-in intspec. If there
+	 * is none, we are nice and just walk up the tree
+	 */
+	do {
+		tmp = of_get_property(ipar, "#interrupt-cells", NULL);
+		if (tmp != NULL) {
+			intsize = be32_to_cpu(*tmp);
+			break;
+		}
+		tnode = ipar;
+		ipar = of_irq_find_parent(ipar);
+		of_node_put(tnode);
+	} while (ipar);
+	if (ipar == NULL) {
+		pr_debug(" -> no parent found !\n");
+		goto fail;
+	}
+
+	pr_debug("of_irq_parse_raw: ipar=%s, size=%d\n", of_node_full_name(ipar), intsize);
+
+	if (out_irq->args_count != intsize)
+		return -EINVAL;
+
+	/* Look for this #address-cells. We have to implement the old linux
+	 * trick of looking for the parent here as some device-trees rely on it
+	 */
+	old = of_node_get(ipar);
+	do {
+		tmp = of_get_property(old, "#address-cells", NULL);
+		tnode = of_get_parent(old);
+		of_node_put(old);
+		old = tnode;
+	} while (old && tmp == NULL);
+	of_node_put(old);
+	old = NULL;
+	addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp);
+
+	pr_debug(" -> addrsize=%d\n", addrsize);
+
+	/* Range check so that the temporary buffer doesn't overflow */
+	if (WARN_ON(addrsize + intsize > MAX_PHANDLE_ARGS))
+		goto fail;
+
+	/* Precalculate the match array - this simplifies match loop */
+	for (i = 0; i < addrsize; i++)
+		initial_match_array[i] = addr ? addr[i] : 0;
+	for (i = 0; i < intsize; i++)
+		initial_match_array[addrsize + i] = cpu_to_be32(out_irq->args[i]);
+
+	/* Now start the actual "proper" walk of the interrupt tree */
+	while (ipar != NULL) {
+		/* Now check if cursor is an interrupt-controller and if it is
+		 * then we are done
+		 */
+		if (of_get_property(ipar, "interrupt-controller", NULL) !=
+				NULL) {
+			pr_debug(" -> got it !\n");
+			return 0;
+		}
+
+		/*
+		 * interrupt-map parsing does not work without a reg
+		 * property when #address-cells != 0
+		 */
+		if (addrsize && !addr) {
+			pr_debug(" -> no reg passed in when needed !\n");
+			goto fail;
+		}
+
+		/* Now look for an interrupt-map */
+		imap = of_get_property(ipar, "interrupt-map", &imaplen);
+		/* No interrupt map, check for an interrupt parent */
+		if (imap == NULL) {
+			pr_debug(" -> no map, getting parent\n");
+			newpar = of_irq_find_parent(ipar);
+			goto skiplevel;
+		}
+		imaplen /= sizeof(u32);
+
+		/* Look for a mask */
+		imask = of_get_property(ipar, "interrupt-map-mask", NULL);
+		if (!imask)
+			imask = dummy_imask;
+
+		/* Parse interrupt-map */
+		match = 0;
+		while (imaplen > (addrsize + intsize + 1) && !match) {
+			/* Compare specifiers */
+			match = 1;
+			for (i = 0; i < (addrsize + intsize); i++, imaplen--)
+				match &= !((match_array[i] ^ *imap++) & imask[i]);
+
+			pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen);
+
+			/* Get the interrupt parent */
+			if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
+				newpar = of_node_get(of_irq_dflt_pic);
+			else
+				newpar = of_find_node_by_phandle(be32_to_cpup(imap));
+			imap++;
+			--imaplen;
+
+			/* Check if not found */
+			if (newpar == NULL) {
+				pr_debug(" -> imap parent not found !\n");
+				goto fail;
+			}
+
+			if (!of_device_is_available(newpar))
+				match = 0;
+
+			/* Get #interrupt-cells and #address-cells of new
+			 * parent
+			 */
+			tmp = of_get_property(newpar, "#interrupt-cells", NULL);
+			if (tmp == NULL) {
+				pr_debug(" -> parent lacks #interrupt-cells!\n");
+				goto fail;
+			}
+			newintsize = be32_to_cpu(*tmp);
+			tmp = of_get_property(newpar, "#address-cells", NULL);
+			newaddrsize = (tmp == NULL) ? 0 : be32_to_cpu(*tmp);
+
+			pr_debug(" -> newintsize=%d, newaddrsize=%d\n",
+			    newintsize, newaddrsize);
+
+			/* Check for malformed properties */
+			if (WARN_ON(newaddrsize + newintsize > MAX_PHANDLE_ARGS))
+				goto fail;
+			if (imaplen < (newaddrsize + newintsize))
+				goto fail;
+
+			imap += newaddrsize + newintsize;
+			imaplen -= newaddrsize + newintsize;
+
+			pr_debug(" -> imaplen=%d\n", imaplen);
+		}
+		if (!match)
+			goto fail;
+
+		/*
+		 * Successfully parsed an interrrupt-map translation; copy new
+		 * interrupt specifier into the out_irq structure
+		 */
+		out_irq->np = newpar;
+
+		match_array = imap - newaddrsize - newintsize;
+		for (i = 0; i < newintsize; i++)
+			out_irq->args[i] = be32_to_cpup(imap - newintsize + i);
+		out_irq->args_count = intsize = newintsize;
+		addrsize = newaddrsize;
+
+	skiplevel:
+		/* Iterate again with new parent */
+		pr_debug(" -> new parent: %s\n", of_node_full_name(newpar));
+		of_node_put(ipar);
+		ipar = newpar;
+		newpar = NULL;
+	}
+ fail:
+	of_node_put(ipar);
+	of_node_put(newpar);
+
+	return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(of_irq_parse_raw);
+
+/**
+ * of_irq_parse_one - Resolve an interrupt for a device
+ * @device: the device whose interrupt is to be resolved
+ * @index: index of the interrupt to resolve
+ * @out_irq: structure of_irq filled by this function
+ *
+ * This function resolves an interrupt for a node by walking the interrupt tree,
+ * finding which interrupt controller node it is attached to, and returning the
+ * interrupt specifier that can be used to retrieve a Linux IRQ number.
+ */
+int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_args *out_irq)
+{
+	struct device_node *p;
+	const __be32 *intspec, *tmp, *addr;
+	u32 intsize, intlen;
+	int i, res;
+
+	pr_debug("of_irq_parse_one: dev=%s, index=%d\n", of_node_full_name(device), index);
+
+	/* OldWorld mac stuff is "special", handle out of line */
+	if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
+		return of_irq_parse_oldworld(device, index, out_irq);
+
+	/* Get the reg property (if any) */
+	addr = of_get_property(device, "reg", NULL);
+
+	/* Try the new-style interrupts-extended first */
+	res = of_parse_phandle_with_args(device, "interrupts-extended",
+					"#interrupt-cells", index, out_irq);
+	if (!res)
+		return of_irq_parse_raw(addr, out_irq);
+
+	/* Get the interrupts property */
+	intspec = of_get_property(device, "interrupts", &intlen);
+	if (intspec == NULL)
+		return -EINVAL;
+
+	intlen /= sizeof(*intspec);
+
+	pr_debug(" intspec=%d intlen=%d\n", be32_to_cpup(intspec), intlen);
+
+	/* Look for the interrupt parent. */
+	p = of_irq_find_parent(device);
+	if (p == NULL)
+		return -EINVAL;
+
+	/* Get size of interrupt specifier */
+	tmp = of_get_property(p, "#interrupt-cells", NULL);
+	if (tmp == NULL) {
+		res = -EINVAL;
+		goto out;
+	}
+	intsize = be32_to_cpu(*tmp);
+
+	pr_debug(" intsize=%d intlen=%d\n", intsize, intlen);
+
+	/* Check index */
+	if ((index + 1) * intsize > intlen) {
+		res = -EINVAL;
+		goto out;
+	}
+
+	/* Copy intspec into irq structure */
+	intspec += index * intsize;
+	out_irq->np = p;
+	out_irq->args_count = intsize;
+	for (i = 0; i < intsize; i++)
+		out_irq->args[i] = be32_to_cpup(intspec++);
+
+	/* Check if there are any interrupt-map translations to process */
+	res = of_irq_parse_raw(addr, out_irq);
+ out:
+	of_node_put(p);
+	return res;
+}
+EXPORT_SYMBOL_GPL(of_irq_parse_one);
+
+/**
+ * of_irq_to_resource - Decode a node's IRQ and return it as a resource
+ * @dev: pointer to device tree node
+ * @index: zero-based index of the irq
+ * @r: pointer to resource structure to return result into.
+ */
+int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)
+{
+	int irq = irq_of_parse_and_map(dev, index);
+
+	/* Only dereference the resource if both the
+	 * resource and the irq are valid. */
+	if (r && irq) {
+		const char *name = NULL;
+
+		memset(r, 0, sizeof(*r));
+		/*
+		 * Get optional "interrupt-names" property to add a name
+		 * to the resource.
+		 */
+		of_property_read_string_index(dev, "interrupt-names", index,
+					      &name);
+
+		r->start = r->end = irq;
+		r->flags = IORESOURCE_IRQ | irqd_get_trigger_type(irq_get_irq_data(irq));
+		r->name = name ? name : of_node_full_name(dev);
+	}
+
+	return irq;
+}
+EXPORT_SYMBOL_GPL(of_irq_to_resource);
+
+/**
+ * of_irq_get - Decode a node's IRQ and return it as a Linux irq number
+ * @dev: pointer to device tree node
+ * @index: zero-based index of the irq
+ *
+ * Returns Linux irq number on success, or -EPROBE_DEFER if the irq domain
+ * is not yet created.
+ *
+ */
+int of_irq_get(struct device_node *dev, int index)
+{
+	int rc;
+	struct of_phandle_args oirq;
+	struct irq_domain *domain;
+
+	rc = of_irq_parse_one(dev, index, &oirq);
+	if (rc)
+		return rc;
+
+	domain = irq_find_host(oirq.np);
+	if (!domain)
+		return -EPROBE_DEFER;
+
+	return irq_create_of_mapping(&oirq);
+}
+EXPORT_SYMBOL_GPL(of_irq_get);
+
+/**
+ * of_irq_get_byname - Decode a node's IRQ and return it as a Linux irq number
+ * @dev: pointer to device tree node
+ * @name: irq name
+ *
+ * Returns Linux irq number on success, or -EPROBE_DEFER if the irq domain
+ * is not yet created, or error code in case of any other failure.
+ */
+int of_irq_get_byname(struct device_node *dev, const char *name)
+{
+	int index;
+
+	if (unlikely(!name))
+		return -EINVAL;
+
+	index = of_property_match_string(dev, "interrupt-names", name);
+	if (index < 0)
+		return index;
+
+	return of_irq_get(dev, index);
+}
+
+/**
+ * of_irq_count - Count the number of IRQs a node uses
+ * @dev: pointer to device tree node
+ */
+int of_irq_count(struct device_node *dev)
+{
+	struct of_phandle_args irq;
+	int nr = 0;
+
+	while (of_irq_parse_one(dev, nr, &irq) == 0)
+		nr++;
+
+	return nr;
+}
+
+/**
+ * of_irq_to_resource_table - Fill in resource table with node's IRQ info
+ * @dev: pointer to device tree node
+ * @res: array of resources to fill in
+ * @nr_irqs: the number of IRQs (and upper bound for num of @res elements)
+ *
+ * Returns the size of the filled in table (up to @nr_irqs).
+ */
+int of_irq_to_resource_table(struct device_node *dev, struct resource *res,
+		int nr_irqs)
+{
+	int i;
+
+	for (i = 0; i < nr_irqs; i++, res++)
+		if (!of_irq_to_resource(dev, i, res))
+			break;
+
+	return i;
+}
+EXPORT_SYMBOL_GPL(of_irq_to_resource_table);
+
+struct intc_desc {
+	struct list_head	list;
+	struct device_node	*dev;
+	struct device_node	*interrupt_parent;
+};
+
+/**
+ * of_irq_init - Scan and init matching interrupt controllers in DT
+ * @matches: 0 terminated array of nodes to match and init function to call
+ *
+ * This function scans the device tree for matching interrupt controller nodes,
+ * and calls their initialization functions in order with parents first.
+ */
+void __init of_irq_init(const struct of_device_id *matches)
+{
+	struct device_node *np, *parent = NULL;
+	struct intc_desc *desc, *temp_desc;
+	struct list_head intc_desc_list, intc_parent_list;
+
+	INIT_LIST_HEAD(&intc_desc_list);
+	INIT_LIST_HEAD(&intc_parent_list);
+
+	for_each_matching_node(np, matches) {
+		if (!of_find_property(np, "interrupt-controller", NULL) ||
+				!of_device_is_available(np))
+			continue;
+		/*
+		 * Here, we allocate and populate an intc_desc with the node
+		 * pointer, interrupt-parent device_node etc.
+		 */
+		desc = kzalloc(sizeof(*desc), GFP_KERNEL);
+		if (WARN_ON(!desc))
+			goto err;
+
+		desc->dev = np;
+		desc->interrupt_parent = of_irq_find_parent(np);
+		if (desc->interrupt_parent == np)
+			desc->interrupt_parent = NULL;
+		list_add_tail(&desc->list, &intc_desc_list);
+	}
+
+	/*
+	 * The root irq controller is the one without an interrupt-parent.
+	 * That one goes first, followed by the controllers that reference it,
+	 * followed by the ones that reference the 2nd level controllers, etc.
+	 */
+	while (!list_empty(&intc_desc_list)) {
+		/*
+		 * Process all controllers with the current 'parent'.
+		 * First pass will be looking for NULL as the parent.
+		 * The assumption is that NULL parent means a root controller.
+		 */
+		list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
+			const struct of_device_id *match;
+			int ret;
+			of_irq_init_cb_t irq_init_cb;
+
+			if (desc->interrupt_parent != parent)
+				continue;
+
+			list_del(&desc->list);
+			match = of_match_node(matches, desc->dev);
+			if (WARN(!match->data,
+			    "of_irq_init: no init function for %s\n",
+			    match->compatible)) {
+				kfree(desc);
+				continue;
+			}
+
+			pr_debug("of_irq_init: init %s @ %p, parent %p\n",
+				 match->compatible,
+				 desc->dev, desc->interrupt_parent);
+			irq_init_cb = (of_irq_init_cb_t)match->data;
+			ret = irq_init_cb(desc->dev, desc->interrupt_parent);
+			if (ret) {
+				kfree(desc);
+				continue;
+			}
+
+			/*
+			 * This one is now set up; add it to the parent list so
+			 * its children can get processed in a subsequent pass.
+			 */
+			list_add_tail(&desc->list, &intc_parent_list);
+		}
+
+		/* Get the next pending parent that might have children */
+		desc = list_first_entry_or_null(&intc_parent_list,
+						typeof(*desc), list);
+		if (!desc) {
+			pr_err("of_irq_init: children remain, but no parents\n");
+			break;
+		}
+		list_del(&desc->list);
+		parent = desc->dev;
+		kfree(desc);
+	}
+
+	list_for_each_entry_safe(desc, temp_desc, &intc_parent_list, list) {
+		list_del(&desc->list);
+		kfree(desc);
+	}
+err:
+	list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
+		list_del(&desc->list);
+		kfree(desc);
+	}
+}
diff --git a/kernel/drivers/of/of_mdio.c b/kernel/drivers/of/of_mdio.c
new file mode 100644
index 000000000..0c064485d
--- /dev/null
+++ b/kernel/drivers/of/of_mdio.c
@@ -0,0 +1,323 @@
+/*
+ * OF helpers for the MDIO (Ethernet PHY) API
+ *
+ * Copyright (c) 2009 Secret Lab Technologies, Ltd.
+ *
+ * This file is released under the GPLv2
+ *
+ * This file provides helper functions for extracting PHY device information
+ * out of the OpenFirmware device tree and using it to populate an mii_bus.
+ */
+
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/netdevice.h>
+#include <linux/err.h>
+#include <linux/phy.h>
+#include <linux/phy_fixed.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_mdio.h>
+#include <linux/module.h>
+
+MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
+MODULE_LICENSE("GPL");
+
+/* Extract the clause 22 phy ID from the compatible string of the form
+ * ethernet-phy-idAAAA.BBBB */
+static int of_get_phy_id(struct device_node *device, u32 *phy_id)
+{
+	struct property *prop;
+	const char *cp;
+	unsigned int upper, lower;
+
+	of_property_for_each_string(device, "compatible", prop, cp) {
+		if (sscanf(cp, "ethernet-phy-id%4x.%4x", &upper, &lower) == 2) {
+			*phy_id = ((upper & 0xFFFF) << 16) | (lower & 0xFFFF);
+			return 0;
+		}
+	}
+	return -EINVAL;
+}
+
+static int of_mdiobus_register_phy(struct mii_bus *mdio, struct device_node *child,
+				   u32 addr)
+{
+	struct phy_device *phy;
+	bool is_c45;
+	int rc;
+	u32 phy_id;
+
+	is_c45 = of_device_is_compatible(child,
+					 "ethernet-phy-ieee802.3-c45");
+
+	if (!is_c45 && !of_get_phy_id(child, &phy_id))
+		phy = phy_device_create(mdio, addr, phy_id, 0, NULL);
+	else
+		phy = get_phy_device(mdio, addr, is_c45);
+	if (!phy || IS_ERR(phy))
+		return 1;
+
+	rc = irq_of_parse_and_map(child, 0);
+	if (rc > 0) {
+		phy->irq = rc;
+		if (mdio->irq)
+			mdio->irq[addr] = rc;
+	} else {
+		if (mdio->irq)
+			phy->irq = mdio->irq[addr];
+	}
+
+	/* Associate the OF node with the device structure so it
+	 * can be looked up later */
+	of_node_get(child);
+	phy->dev.of_node = child;
+
+	/* All data is now stored in the phy struct;
+	 * register it */
+	rc = phy_device_register(phy);
+	if (rc) {
+		phy_device_free(phy);
+		of_node_put(child);
+		return 1;
+	}
+
+	dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
+		child->name, addr);
+
+	return 0;
+}
+
+int of_mdio_parse_addr(struct device *dev, const struct device_node *np)
+{
+	u32 addr;
+	int ret;
+
+	ret = of_property_read_u32(np, "reg", &addr);
+	if (ret < 0) {
+		dev_err(dev, "%s has invalid PHY address\n", np->full_name);
+		return ret;
+	}
+
+	/* A PHY must have a reg property in the range [0-31] */
+	if (addr >= PHY_MAX_ADDR) {
+		dev_err(dev, "%s PHY address %i is too large\n",
+			np->full_name, addr);
+		return -EINVAL;
+	}
+
+	return addr;
+}
+EXPORT_SYMBOL(of_mdio_parse_addr);
+
+/**
+ * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
+ * @mdio: pointer to mii_bus structure
+ * @np: pointer to device_node of MDIO bus.
+ *
+ * This function registers the mii_bus structure and registers a phy_device
+ * for each child node of @np.
+ */
+int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
+{
+	struct device_node *child;
+	const __be32 *paddr;
+	bool scanphys = false;
+	int addr, rc, i;
+
+	/* Mask out all PHYs from auto probing.  Instead the PHYs listed in
+	 * the device tree are populated after the bus has been registered */
+	mdio->phy_mask = ~0;
+
+	/* Clear all the IRQ properties */
+	if (mdio->irq)
+		for (i=0; i<PHY_MAX_ADDR; i++)
+			mdio->irq[i] = PHY_POLL;
+
+	mdio->dev.of_node = np;
+
+	/* Register the MDIO bus */
+	rc = mdiobus_register(mdio);
+	if (rc)
+		return rc;
+
+	/* Loop over the child nodes and register a phy_device for each one */
+	for_each_available_child_of_node(np, child) {
+		addr = of_mdio_parse_addr(&mdio->dev, child);
+		if (addr < 0) {
+			scanphys = true;
+			continue;
+		}
+
+		rc = of_mdiobus_register_phy(mdio, child, addr);
+		if (rc)
+			continue;
+	}
+
+	if (!scanphys)
+		return 0;
+
+	/* auto scan for PHYs with empty reg property */
+	for_each_available_child_of_node(np, child) {
+		/* Skip PHYs with reg property set */
+		paddr = of_get_property(child, "reg", NULL);
+		if (paddr)
+			continue;
+
+		for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
+			/* skip already registered PHYs */
+			if (mdio->phy_map[addr])
+				continue;
+
+			/* be noisy to encourage people to set reg property */
+			dev_info(&mdio->dev, "scan phy %s at address %i\n",
+				 child->name, addr);
+
+			rc = of_mdiobus_register_phy(mdio, child, addr);
+			if (rc)
+				continue;
+		}
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(of_mdiobus_register);
+
+/* Helper function for of_phy_find_device */
+static int of_phy_match(struct device *dev, void *phy_np)
+{
+	return dev->of_node == phy_np;
+}
+
+/**
+ * of_phy_find_device - Give a PHY node, find the phy_device
+ * @phy_np: Pointer to the phy's device tree node
+ *
+ * Returns a pointer to the phy_device.
+ */
+struct phy_device *of_phy_find_device(struct device_node *phy_np)
+{
+	struct device *d;
+	if (!phy_np)
+		return NULL;
+
+	d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
+	return d ? to_phy_device(d) : NULL;
+}
+EXPORT_SYMBOL(of_phy_find_device);
+
+/**
+ * of_phy_connect - Connect to the phy described in the device tree
+ * @dev: pointer to net_device claiming the phy
+ * @phy_np: Pointer to device tree node for the PHY
+ * @hndlr: Link state callback for the network device
+ * @iface: PHY data interface type
+ *
+ * Returns a pointer to the phy_device if successful.  NULL otherwise
+ */
+struct phy_device *of_phy_connect(struct net_device *dev,
+				  struct device_node *phy_np,
+				  void (*hndlr)(struct net_device *), u32 flags,
+				  phy_interface_t iface)
+{
+	struct phy_device *phy = of_phy_find_device(phy_np);
+
+	if (!phy)
+		return NULL;
+
+	phy->dev_flags = flags;
+
+	return phy_connect_direct(dev, phy, hndlr, iface) ? NULL : phy;
+}
+EXPORT_SYMBOL(of_phy_connect);
+
+/**
+ * of_phy_attach - Attach to a PHY without starting the state machine
+ * @dev: pointer to net_device claiming the phy
+ * @phy_np: Node pointer for the PHY
+ * @flags: flags to pass to the PHY
+ * @iface: PHY data interface type
+ */
+struct phy_device *of_phy_attach(struct net_device *dev,
+				 struct device_node *phy_np, u32 flags,
+				 phy_interface_t iface)
+{
+	struct phy_device *phy = of_phy_find_device(phy_np);
+
+	if (!phy)
+		return NULL;
+
+	return phy_attach_direct(dev, phy, flags, iface) ? NULL : phy;
+}
+EXPORT_SYMBOL(of_phy_attach);
+
+#if defined(CONFIG_FIXED_PHY)
+/*
+ * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
+ * support two DT bindings:
+ * - the old DT binding, where 'fixed-link' was a property with 5
+ *   cells encoding various informations about the fixed PHY
+ * - the new DT binding, where 'fixed-link' is a sub-node of the
+ *   Ethernet device.
+ */
+bool of_phy_is_fixed_link(struct device_node *np)
+{
+	struct device_node *dn;
+	int len;
+
+	/* New binding */
+	dn = of_get_child_by_name(np, "fixed-link");
+	if (dn) {
+		of_node_put(dn);
+		return true;
+	}
+
+	/* Old binding */
+	if (of_get_property(np, "fixed-link", &len) &&
+	    len == (5 * sizeof(__be32)))
+		return true;
+
+	return false;
+}
+EXPORT_SYMBOL(of_phy_is_fixed_link);
+
+int of_phy_register_fixed_link(struct device_node *np)
+{
+	struct fixed_phy_status status = {};
+	struct device_node *fixed_link_node;
+	const __be32 *fixed_link_prop;
+	int len;
+	struct phy_device *phy;
+
+	/* New binding */
+	fixed_link_node = of_get_child_by_name(np, "fixed-link");
+	if (fixed_link_node) {
+		status.link = 1;
+		status.duplex = of_property_read_bool(fixed_link_node,
+						      "full-duplex");
+		if (of_property_read_u32(fixed_link_node, "speed", &status.speed))
+			return -EINVAL;
+		status.pause = of_property_read_bool(fixed_link_node, "pause");
+		status.asym_pause = of_property_read_bool(fixed_link_node,
+							  "asym-pause");
+		of_node_put(fixed_link_node);
+		phy = fixed_phy_register(PHY_POLL, &status, np);
+		return IS_ERR(phy) ? PTR_ERR(phy) : 0;
+	}
+
+	/* Old binding */
+	fixed_link_prop = of_get_property(np, "fixed-link", &len);
+	if (fixed_link_prop && len == (5 * sizeof(__be32))) {
+		status.link = 1;
+		status.duplex = be32_to_cpu(fixed_link_prop[1]);
+		status.speed = be32_to_cpu(fixed_link_prop[2]);
+		status.pause = be32_to_cpu(fixed_link_prop[3]);
+		status.asym_pause = be32_to_cpu(fixed_link_prop[4]);
+		phy = fixed_phy_register(PHY_POLL, &status, np);
+		return IS_ERR(phy) ? PTR_ERR(phy) : 0;
+	}
+
+	return -ENODEV;
+}
+EXPORT_SYMBOL(of_phy_register_fixed_link);
+#endif
diff --git a/kernel/drivers/of/of_mtd.c b/kernel/drivers/of/of_mtd.c
new file mode 100644
index 000000000..b7361ed70
--- /dev/null
+++ b/kernel/drivers/of/of_mtd.c
@@ -0,0 +1,119 @@
+/*
+ * Copyright 2012 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
+ *
+ * OF helpers for mtd.
+ *
+ * This file is released under the GPLv2
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/of_mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/export.h>
+
+/**
+ * It maps 'enum nand_ecc_modes_t' found in include/linux/mtd/nand.h
+ * into the device tree binding of 'nand-ecc', so that MTD
+ * device driver can get nand ecc from device tree.
+ */
+static const char *nand_ecc_modes[] = {
+	[NAND_ECC_NONE]		= "none",
+	[NAND_ECC_SOFT]		= "soft",
+	[NAND_ECC_HW]		= "hw",
+	[NAND_ECC_HW_SYNDROME]	= "hw_syndrome",
+	[NAND_ECC_HW_OOB_FIRST]	= "hw_oob_first",
+	[NAND_ECC_SOFT_BCH]	= "soft_bch",
+};
+
+/**
+ * of_get_nand_ecc_mode - Get nand ecc mode for given device_node
+ * @np:	Pointer to the given device_node
+ *
+ * The function gets ecc mode string from property 'nand-ecc-mode',
+ * and return its index in nand_ecc_modes table, or errno in error case.
+ */
+int of_get_nand_ecc_mode(struct device_node *np)
+{
+	const char *pm;
+	int err, i;
+
+	err = of_property_read_string(np, "nand-ecc-mode", &pm);
+	if (err < 0)
+		return err;
+
+	for (i = 0; i < ARRAY_SIZE(nand_ecc_modes); i++)
+		if (!strcasecmp(pm, nand_ecc_modes[i]))
+			return i;
+
+	return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(of_get_nand_ecc_mode);
+
+/**
+ * of_get_nand_ecc_step_size - Get ECC step size associated to
+ * the required ECC strength (see below).
+ * @np:	Pointer to the given device_node
+ *
+ * return the ECC step size, or errno in error case.
+ */
+int of_get_nand_ecc_step_size(struct device_node *np)
+{
+	int ret;
+	u32 val;
+
+	ret = of_property_read_u32(np, "nand-ecc-step-size", &val);
+	return ret ? ret : val;
+}
+EXPORT_SYMBOL_GPL(of_get_nand_ecc_step_size);
+
+/**
+ * of_get_nand_ecc_strength - Get required ECC strength over the
+ * correspnding step size as defined by 'nand-ecc-size'
+ * @np:	Pointer to the given device_node
+ *
+ * return the ECC strength, or errno in error case.
+ */
+int of_get_nand_ecc_strength(struct device_node *np)
+{
+	int ret;
+	u32 val;
+
+	ret = of_property_read_u32(np, "nand-ecc-strength", &val);
+	return ret ? ret : val;
+}
+EXPORT_SYMBOL_GPL(of_get_nand_ecc_strength);
+
+/**
+ * of_get_nand_bus_width - Get nand bus witdh for given device_node
+ * @np:	Pointer to the given device_node
+ *
+ * return bus width option, or errno in error case.
+ */
+int of_get_nand_bus_width(struct device_node *np)
+{
+	u32 val;
+
+	if (of_property_read_u32(np, "nand-bus-width", &val))
+		return 8;
+
+	switch(val) {
+	case 8:
+	case 16:
+		return val;
+	default:
+		return -EIO;
+	}
+}
+EXPORT_SYMBOL_GPL(of_get_nand_bus_width);
+
+/**
+ * of_get_nand_on_flash_bbt - Get nand on flash bbt for given device_node
+ * @np:	Pointer to the given device_node
+ *
+ * return true if present false other wise
+ */
+bool of_get_nand_on_flash_bbt(struct device_node *np)
+{
+	return of_property_read_bool(np, "nand-on-flash-bbt");
+}
+EXPORT_SYMBOL_GPL(of_get_nand_on_flash_bbt);
diff --git a/kernel/drivers/of/of_net.c b/kernel/drivers/of/of_net.c
new file mode 100644
index 000000000..d820f3edd
--- /dev/null
+++ b/kernel/drivers/of/of_net.c
@@ -0,0 +1,82 @@
+/*
+ * OF helpers for network devices.
+ *
+ * This file is released under the GPLv2
+ *
+ * Initially copied out of arch/powerpc/kernel/prom_parse.c
+ */
+#include <linux/etherdevice.h>
+#include <linux/kernel.h>
+#include <linux/of_net.h>
+#include <linux/phy.h>
+#include <linux/export.h>
+
+/**
+ * of_get_phy_mode - Get phy mode for given device_node
+ * @np:	Pointer to the given device_node
+ *
+ * The function gets phy interface string from property 'phy-mode' or
+ * 'phy-connection-type', and return its index in phy_modes table, or errno in
+ * error case.
+ */
+int of_get_phy_mode(struct device_node *np)
+{
+	const char *pm;
+	int err, i;
+
+	err = of_property_read_string(np, "phy-mode", &pm);
+	if (err < 0)
+		err = of_property_read_string(np, "phy-connection-type", &pm);
+	if (err < 0)
+		return err;
+
+	for (i = 0; i < PHY_INTERFACE_MODE_MAX; i++)
+		if (!strcasecmp(pm, phy_modes(i)))
+			return i;
+
+	return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(of_get_phy_mode);
+
+static const void *of_get_mac_addr(struct device_node *np, const char *name)
+{
+	struct property *pp = of_find_property(np, name, NULL);
+
+	if (pp && pp->length == ETH_ALEN && is_valid_ether_addr(pp->value))
+		return pp->value;
+	return NULL;
+}
+
+/**
+ * Search the device tree for the best MAC address to use.  'mac-address' is
+ * checked first, because that is supposed to contain to "most recent" MAC
+ * address. If that isn't set, then 'local-mac-address' is checked next,
+ * because that is the default address.  If that isn't set, then the obsolete
+ * 'address' is checked, just in case we're using an old device tree.
+ *
+ * Note that the 'address' property is supposed to contain a virtual address of
+ * the register set, but some DTS files have redefined that property to be the
+ * MAC address.
+ *
+ * All-zero MAC addresses are rejected, because those could be properties that
+ * exist in the device tree, but were not set by U-Boot.  For example, the
+ * DTS could define 'mac-address' and 'local-mac-address', with zero MAC
+ * addresses.  Some older U-Boots only initialized 'local-mac-address'.  In
+ * this case, the real MAC is in 'local-mac-address', and 'mac-address' exists
+ * but is all zeros.
+*/
+const void *of_get_mac_address(struct device_node *np)
+{
+	const void *addr;
+
+	addr = of_get_mac_addr(np, "mac-address");
+	if (addr)
+		return addr;
+
+	addr = of_get_mac_addr(np, "local-mac-address");
+	if (addr)
+		return addr;
+
+	return of_get_mac_addr(np, "address");
+}
+EXPORT_SYMBOL(of_get_mac_address);
diff --git a/kernel/drivers/of/of_pci.c b/kernel/drivers/of/of_pci.c
new file mode 100644
index 000000000..5751dc5b6
--- /dev/null
+++ b/kernel/drivers/of/of_pci.c
@@ -0,0 +1,301 @@
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_pci.h>
+#include <linux/slab.h>
+
+static inline int __of_pci_pci_compare(struct device_node *node,
+				       unsigned int data)
+{
+	int devfn;
+
+	devfn = of_pci_get_devfn(node);
+	if (devfn < 0)
+		return 0;
+
+	return devfn == data;
+}
+
+struct device_node *of_pci_find_child_device(struct device_node *parent,
+					     unsigned int devfn)
+{
+	struct device_node *node, *node2;
+
+	for_each_child_of_node(parent, node) {
+		if (__of_pci_pci_compare(node, devfn))
+			return node;
+		/*
+		 * Some OFs create a parent node "multifunc-device" as
+		 * a fake root for all functions of a multi-function
+		 * device we go down them as well.
+		 */
+		if (!strcmp(node->name, "multifunc-device")) {
+			for_each_child_of_node(node, node2) {
+				if (__of_pci_pci_compare(node2, devfn)) {
+					of_node_put(node);
+					return node2;
+				}
+			}
+		}
+	}
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(of_pci_find_child_device);
+
+/**
+ * of_pci_get_devfn() - Get device and function numbers for a device node
+ * @np: device node
+ *
+ * Parses a standard 5-cell PCI resource and returns an 8-bit value that can
+ * be passed to the PCI_SLOT() and PCI_FUNC() macros to extract the device
+ * and function numbers respectively. On error a negative error code is
+ * returned.
+ */
+int of_pci_get_devfn(struct device_node *np)
+{
+	unsigned int size;
+	const __be32 *reg;
+
+	reg = of_get_property(np, "reg", &size);
+
+	if (!reg || size < 5 * sizeof(__be32))
+		return -EINVAL;
+
+	return (be32_to_cpup(reg) >> 8) & 0xff;
+}
+EXPORT_SYMBOL_GPL(of_pci_get_devfn);
+
+/**
+ * of_pci_parse_bus_range() - parse the bus-range property of a PCI device
+ * @node: device node
+ * @res: address to a struct resource to return the bus-range
+ *
+ * Returns 0 on success or a negative error-code on failure.
+ */
+int of_pci_parse_bus_range(struct device_node *node, struct resource *res)
+{
+	const __be32 *values;
+	int len;
+
+	values = of_get_property(node, "bus-range", &len);
+	if (!values || len < sizeof(*values) * 2)
+		return -EINVAL;
+
+	res->name = node->name;
+	res->start = be32_to_cpup(values++);
+	res->end = be32_to_cpup(values);
+	res->flags = IORESOURCE_BUS;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_pci_parse_bus_range);
+
+/**
+ * This function will try to obtain the host bridge domain number by
+ * finding a property called "linux,pci-domain" of the given device node.
+ *
+ * @node: device tree node with the domain information
+ *
+ * Returns the associated domain number from DT in the range [0-0xffff], or
+ * a negative value if the required property is not found.
+ */
+int of_get_pci_domain_nr(struct device_node *node)
+{
+	const __be32 *value;
+	int len;
+	u16 domain;
+
+	value = of_get_property(node, "linux,pci-domain", &len);
+	if (!value || len < sizeof(*value))
+		return -EINVAL;
+
+	domain = (u16)be32_to_cpup(value);
+
+	return domain;
+}
+EXPORT_SYMBOL_GPL(of_get_pci_domain_nr);
+
+/**
+ * of_pci_dma_configure - Setup DMA configuration
+ * @dev: ptr to pci_dev struct of the PCI device
+ *
+ * Function to update PCI devices's DMA configuration using the same
+ * info from the OF node of host bridge's parent (if any).
+ */
+void of_pci_dma_configure(struct pci_dev *pci_dev)
+{
+	struct device *dev = &pci_dev->dev;
+	struct device *bridge = pci_get_host_bridge_device(pci_dev);
+
+	if (!bridge->parent)
+		return;
+
+	of_dma_configure(dev, bridge->parent->of_node);
+	pci_put_host_bridge_device(bridge);
+}
+EXPORT_SYMBOL_GPL(of_pci_dma_configure);
+
+#if defined(CONFIG_OF_ADDRESS)
+/**
+ * of_pci_get_host_bridge_resources - Parse PCI host bridge resources from DT
+ * @dev: device node of the host bridge having the range property
+ * @busno: bus number associated with the bridge root bus
+ * @bus_max: maximum number of buses for this bridge
+ * @resources: list where the range of resources will be added after DT parsing
+ * @io_base: pointer to a variable that will contain on return the physical
+ * address for the start of the I/O range. Can be NULL if the caller doesn't
+ * expect IO ranges to be present in the device tree.
+ *
+ * It is the caller's job to free the @resources list.
+ *
+ * This function will parse the "ranges" property of a PCI host bridge device
+ * node and setup the resource mapping based on its content. It is expected
+ * that the property conforms with the Power ePAPR document.
+ *
+ * It returns zero if the range parsing has been successful or a standard error
+ * value if it failed.
+ */
+int of_pci_get_host_bridge_resources(struct device_node *dev,
+			unsigned char busno, unsigned char bus_max,
+			struct list_head *resources, resource_size_t *io_base)
+{
+	struct resource_entry *window;
+	struct resource *res;
+	struct resource *bus_range;
+	struct of_pci_range range;
+	struct of_pci_range_parser parser;
+	char range_type[4];
+	int err;
+
+	if (io_base)
+		*io_base = (resource_size_t)OF_BAD_ADDR;
+
+	bus_range = kzalloc(sizeof(*bus_range), GFP_KERNEL);
+	if (!bus_range)
+		return -ENOMEM;
+
+	pr_info("PCI host bridge %s ranges:\n", dev->full_name);
+
+	err = of_pci_parse_bus_range(dev, bus_range);
+	if (err) {
+		bus_range->start = busno;
+		bus_range->end = bus_max;
+		bus_range->flags = IORESOURCE_BUS;
+		pr_info("  No bus range found for %s, using %pR\n",
+			dev->full_name, bus_range);
+	} else {
+		if (bus_range->end > bus_range->start + bus_max)
+			bus_range->end = bus_range->start + bus_max;
+	}
+	pci_add_resource(resources, bus_range);
+
+	/* Check for ranges property */
+	err = of_pci_range_parser_init(&parser, dev);
+	if (err)
+		goto parse_failed;
+
+	pr_debug("Parsing ranges property...\n");
+	for_each_of_pci_range(&parser, &range) {
+		/* Read next ranges element */
+		if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_IO)
+			snprintf(range_type, 4, " IO");
+		else if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_MEM)
+			snprintf(range_type, 4, "MEM");
+		else
+			snprintf(range_type, 4, "err");
+		pr_info("  %s %#010llx..%#010llx -> %#010llx\n", range_type,
+			range.cpu_addr, range.cpu_addr + range.size - 1,
+			range.pci_addr);
+
+		/*
+		 * If we failed translation or got a zero-sized region
+		 * then skip this range
+		 */
+		if (range.cpu_addr == OF_BAD_ADDR || range.size == 0)
+			continue;
+
+		res = kzalloc(sizeof(struct resource), GFP_KERNEL);
+		if (!res) {
+			err = -ENOMEM;
+			goto parse_failed;
+		}
+
+		err = of_pci_range_to_resource(&range, dev, res);
+		if (err)
+			goto conversion_failed;
+
+		if (resource_type(res) == IORESOURCE_IO) {
+			if (!io_base) {
+				pr_err("I/O range found for %s. Please provide an io_base pointer to save CPU base address\n",
+					dev->full_name);
+				err = -EINVAL;
+				goto conversion_failed;
+			}
+			if (*io_base != (resource_size_t)OF_BAD_ADDR)
+				pr_warn("More than one I/O resource converted for %s. CPU base address for old range lost!\n",
+					dev->full_name);
+			*io_base = range.cpu_addr;
+		}
+
+		pci_add_resource_offset(resources, res,	res->start - range.pci_addr);
+	}
+
+	return 0;
+
+conversion_failed:
+	kfree(res);
+parse_failed:
+	resource_list_for_each_entry(window, resources)
+		kfree(window->res);
+	pci_free_resource_list(resources);
+	return err;
+}
+EXPORT_SYMBOL_GPL(of_pci_get_host_bridge_resources);
+#endif /* CONFIG_OF_ADDRESS */
+
+#ifdef CONFIG_PCI_MSI
+
+static LIST_HEAD(of_pci_msi_chip_list);
+static DEFINE_MUTEX(of_pci_msi_chip_mutex);
+
+int of_pci_msi_chip_add(struct msi_controller *chip)
+{
+	if (!of_property_read_bool(chip->of_node, "msi-controller"))
+		return -EINVAL;
+
+	mutex_lock(&of_pci_msi_chip_mutex);
+	list_add(&chip->list, &of_pci_msi_chip_list);
+	mutex_unlock(&of_pci_msi_chip_mutex);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_pci_msi_chip_add);
+
+void of_pci_msi_chip_remove(struct msi_controller *chip)
+{
+	mutex_lock(&of_pci_msi_chip_mutex);
+	list_del(&chip->list);
+	mutex_unlock(&of_pci_msi_chip_mutex);
+}
+EXPORT_SYMBOL_GPL(of_pci_msi_chip_remove);
+
+struct msi_controller *of_pci_find_msi_chip_by_node(struct device_node *of_node)
+{
+	struct msi_controller *c;
+
+	mutex_lock(&of_pci_msi_chip_mutex);
+	list_for_each_entry(c, &of_pci_msi_chip_list, list) {
+		if (c->of_node == of_node) {
+			mutex_unlock(&of_pci_msi_chip_mutex);
+			return c;
+		}
+	}
+	mutex_unlock(&of_pci_msi_chip_mutex);
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(of_pci_find_msi_chip_by_node);
+
+#endif /* CONFIG_PCI_MSI */
diff --git a/kernel/drivers/of/of_pci_irq.c b/kernel/drivers/of/of_pci_irq.c
new file mode 100644
index 000000000..1710d9dc7
--- /dev/null
+++ b/kernel/drivers/of/of_pci_irq.c
@@ -0,0 +1,116 @@
+#include <linux/kernel.h>
+#include <linux/of_pci.h>
+#include <linux/of_irq.h>
+#include <linux/export.h>
+
+/**
+ * of_irq_parse_pci - Resolve the interrupt for a PCI device
+ * @pdev:       the device whose interrupt is to be resolved
+ * @out_irq:    structure of_irq filled by this function
+ *
+ * This function resolves the PCI interrupt for a given PCI device. If a
+ * device-node exists for a given pci_dev, it will use normal OF tree
+ * walking. If not, it will implement standard swizzling and walk up the
+ * PCI tree until an device-node is found, at which point it will finish
+ * resolving using the OF tree walking.
+ */
+int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq)
+{
+	struct device_node *dn, *ppnode;
+	struct pci_dev *ppdev;
+	__be32 laddr[3];
+	u8 pin;
+	int rc;
+
+	/* Check if we have a device node, if yes, fallback to standard
+	 * device tree parsing
+	 */
+	dn = pci_device_to_OF_node(pdev);
+	if (dn) {
+		rc = of_irq_parse_one(dn, 0, out_irq);
+		if (!rc)
+			return rc;
+	}
+
+	/* Ok, we don't, time to have fun. Let's start by building up an
+	 * interrupt spec.  we assume #interrupt-cells is 1, which is standard
+	 * for PCI. If you do different, then don't use that routine.
+	 */
+	rc = pci_read_config_byte(pdev, PCI_INTERRUPT_PIN, &pin);
+	if (rc != 0)
+		return rc;
+	/* No pin, exit */
+	if (pin == 0)
+		return -ENODEV;
+
+	/* Now we walk up the PCI tree */
+	for (;;) {
+		/* Get the pci_dev of our parent */
+		ppdev = pdev->bus->self;
+
+		/* Ouch, it's a host bridge... */
+		if (ppdev == NULL) {
+			ppnode = pci_bus_to_OF_node(pdev->bus);
+
+			/* No node for host bridge ? give up */
+			if (ppnode == NULL)
+				return -EINVAL;
+		} else {
+			/* We found a P2P bridge, check if it has a node */
+			ppnode = pci_device_to_OF_node(ppdev);
+		}
+
+		/* Ok, we have found a parent with a device-node, hand over to
+		 * the OF parsing code.
+		 * We build a unit address from the linux device to be used for
+		 * resolution. Note that we use the linux bus number which may
+		 * not match your firmware bus numbering.
+		 * Fortunately, in most cases, interrupt-map-mask doesn't
+		 * include the bus number as part of the matching.
+		 * You should still be careful about that though if you intend
+		 * to rely on this function (you ship  a firmware that doesn't
+		 * create device nodes for all PCI devices).
+		 */
+		if (ppnode)
+			break;
+
+		/* We can only get here if we hit a P2P bridge with no node,
+		 * let's do standard swizzling and try again
+		 */
+		pin = pci_swizzle_interrupt_pin(pdev, pin);
+		pdev = ppdev;
+	}
+
+	out_irq->np = ppnode;
+	out_irq->args_count = 1;
+	out_irq->args[0] = pin;
+	laddr[0] = cpu_to_be32((pdev->bus->number << 16) | (pdev->devfn << 8));
+	laddr[1] = laddr[2] = cpu_to_be32(0);
+	return of_irq_parse_raw(laddr, out_irq);
+}
+EXPORT_SYMBOL_GPL(of_irq_parse_pci);
+
+/**
+ * of_irq_parse_and_map_pci() - Decode a PCI irq from the device tree and map to a virq
+ * @dev: The pci device needing an irq
+ * @slot: PCI slot number; passed when used as map_irq callback. Unused
+ * @pin: PCI irq pin number; passed when used as map_irq callback. Unused
+ *
+ * @slot and @pin are unused, but included in the function so that this
+ * function can be used directly as the map_irq callback to pci_fixup_irqs().
+ */
+int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+	struct of_phandle_args oirq;
+	int ret;
+
+	ret = of_irq_parse_pci(dev, &oirq);
+	if (ret) {
+		dev_err(&dev->dev, "of_irq_parse_pci() failed with rc=%d\n", ret);
+		return 0; /* Proper return code 0 == NO_IRQ */
+	}
+
+	return irq_create_of_mapping(&oirq);
+}
+EXPORT_SYMBOL_GPL(of_irq_parse_and_map_pci);
+
diff --git a/kernel/drivers/of/of_private.h b/kernel/drivers/of/of_private.h
new file mode 100644
index 000000000..8e882e706
--- /dev/null
+++ b/kernel/drivers/of/of_private.h
@@ -0,0 +1,93 @@
+#ifndef _LINUX_OF_PRIVATE_H
+#define _LINUX_OF_PRIVATE_H
+/*
+ * Private symbols used by OF support code
+ *
+ * Paul Mackerras	August 1996.
+ * Copyright (C) 1996-2005 Paul Mackerras.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+/**
+ * struct alias_prop - Alias property in 'aliases' node
+ * @link:	List node to link the structure in aliases_lookup list
+ * @alias:	Alias property name
+ * @np:		Pointer to device_node that the alias stands for
+ * @id:		Index value from end of alias name
+ * @stem:	Alias string without the index
+ *
+ * The structure represents one alias property of 'aliases' node as
+ * an entry in aliases_lookup list.
+ */
+struct alias_prop {
+	struct list_head link;
+	const char *alias;
+	struct device_node *np;
+	int id;
+	char stem[0];
+};
+
+extern struct mutex of_mutex;
+extern struct list_head aliases_lookup;
+extern struct kset *of_kset;
+
+
+static inline struct device_node *kobj_to_device_node(struct kobject *kobj)
+{
+	return container_of(kobj, struct device_node, kobj);
+}
+
+#if defined(CONFIG_OF_DYNAMIC)
+extern int of_property_notify(int action, struct device_node *np,
+			      struct property *prop, struct property *old_prop);
+extern void of_node_release(struct kobject *kobj);
+#else /* CONFIG_OF_DYNAMIC */
+static inline int of_property_notify(int action, struct device_node *np,
+				     struct property *prop, struct property *old_prop)
+{
+	return 0;
+}
+#endif /* CONFIG_OF_DYNAMIC */
+
+/**
+ * General utilities for working with live trees.
+ *
+ * All functions with two leading underscores operate
+ * without taking node references, so you either have to
+ * own the devtree lock or work on detached trees only.
+ */
+struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags);
+__printf(2, 3) struct device_node *__of_node_dup(const struct device_node *np, const char *fmt, ...);
+
+extern const void *__of_get_property(const struct device_node *np,
+				     const char *name, int *lenp);
+extern int __of_add_property(struct device_node *np, struct property *prop);
+extern int __of_add_property_sysfs(struct device_node *np,
+		struct property *prop);
+extern int __of_remove_property(struct device_node *np, struct property *prop);
+extern void __of_remove_property_sysfs(struct device_node *np,
+		struct property *prop);
+extern int __of_update_property(struct device_node *np,
+		struct property *newprop, struct property **oldprop);
+extern void __of_update_property_sysfs(struct device_node *np,
+		struct property *newprop, struct property *oldprop);
+
+extern void __of_attach_node(struct device_node *np);
+extern int __of_attach_node_sysfs(struct device_node *np);
+extern void __of_detach_node(struct device_node *np);
+extern void __of_detach_node_sysfs(struct device_node *np);
+
+/* iterators for transactions, used for overlays */
+/* forward iterator */
+#define for_each_transaction_entry(_oft, _te) \
+	list_for_each_entry(_te, &(_oft)->te_list, node)
+
+/* reverse iterator */
+#define for_each_transaction_entry_reverse(_oft, _te) \
+	list_for_each_entry_reverse(_te, &(_oft)->te_list, node)
+
+#endif /* _LINUX_OF_PRIVATE_H */
diff --git a/kernel/drivers/of/of_reserved_mem.c b/kernel/drivers/of/of_reserved_mem.c
new file mode 100644
index 000000000..726ebe792
--- /dev/null
+++ b/kernel/drivers/of/of_reserved_mem.c
@@ -0,0 +1,293 @@
+/*
+ * Device tree based initialization code for reserved memory.
+ *
+ * Copyright (c) 2013, The Linux Foundation. All Rights Reserved.
+ * Copyright (c) 2013,2014 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ * Author: Marek Szyprowski <m.szyprowski@samsung.com>
+ * Author: Josh Cartwright <joshc@codeaurora.org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License or (at your optional) any later version of the license.
+ */
+
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/of_platform.h>
+#include <linux/mm.h>
+#include <linux/sizes.h>
+#include <linux/of_reserved_mem.h>
+
+#define MAX_RESERVED_REGIONS	16
+static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS];
+static int reserved_mem_count;
+
+#if defined(CONFIG_HAVE_MEMBLOCK)
+#include <linux/memblock.h>
+int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
+	phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
+	phys_addr_t *res_base)
+{
+	/*
+	 * We use __memblock_alloc_base() because memblock_alloc_base()
+	 * panic()s on allocation failure.
+	 */
+	phys_addr_t base = __memblock_alloc_base(size, align, end);
+	if (!base)
+		return -ENOMEM;
+
+	/*
+	 * Check if the allocated region fits in to start..end window
+	 */
+	if (base < start) {
+		memblock_free(base, size);
+		return -ENOMEM;
+	}
+
+	*res_base = base;
+	if (nomap)
+		return memblock_remove(base, size);
+	return 0;
+}
+#else
+int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
+	phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
+	phys_addr_t *res_base)
+{
+	pr_err("Reserved memory not supported, ignoring region 0x%llx%s\n",
+		  size, nomap ? " (nomap)" : "");
+	return -ENOSYS;
+}
+#endif
+
+/**
+ * res_mem_save_node() - save fdt node for second pass initialization
+ */
+void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname,
+				      phys_addr_t base, phys_addr_t size)
+{
+	struct reserved_mem *rmem = &reserved_mem[reserved_mem_count];
+
+	if (reserved_mem_count == ARRAY_SIZE(reserved_mem)) {
+		pr_err("Reserved memory: not enough space all defined regions.\n");
+		return;
+	}
+
+	rmem->fdt_node = node;
+	rmem->name = uname;
+	rmem->base = base;
+	rmem->size = size;
+
+	reserved_mem_count++;
+	return;
+}
+
+/**
+ * res_mem_alloc_size() - allocate reserved memory described by 'size', 'align'
+ *			  and 'alloc-ranges' properties
+ */
+static int __init __reserved_mem_alloc_size(unsigned long node,
+	const char *uname, phys_addr_t *res_base, phys_addr_t *res_size)
+{
+	int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
+	phys_addr_t start = 0, end = 0;
+	phys_addr_t base = 0, align = 0, size;
+	int len;
+	const __be32 *prop;
+	int nomap;
+	int ret;
+
+	prop = of_get_flat_dt_prop(node, "size", &len);
+	if (!prop)
+		return -EINVAL;
+
+	if (len != dt_root_size_cells * sizeof(__be32)) {
+		pr_err("Reserved memory: invalid size property in '%s' node.\n",
+				uname);
+		return -EINVAL;
+	}
+	size = dt_mem_next_cell(dt_root_size_cells, &prop);
+
+	nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
+
+	prop = of_get_flat_dt_prop(node, "alignment", &len);
+	if (prop) {
+		if (len != dt_root_addr_cells * sizeof(__be32)) {
+			pr_err("Reserved memory: invalid alignment property in '%s' node.\n",
+				uname);
+			return -EINVAL;
+		}
+		align = dt_mem_next_cell(dt_root_addr_cells, &prop);
+	}
+
+	prop = of_get_flat_dt_prop(node, "alloc-ranges", &len);
+	if (prop) {
+
+		if (len % t_len != 0) {
+			pr_err("Reserved memory: invalid alloc-ranges property in '%s', skipping node.\n",
+			       uname);
+			return -EINVAL;
+		}
+
+		base = 0;
+
+		while (len > 0) {
+			start = dt_mem_next_cell(dt_root_addr_cells, &prop);
+			end = start + dt_mem_next_cell(dt_root_size_cells,
+						       &prop);
+
+			ret = early_init_dt_alloc_reserved_memory_arch(size,
+					align, start, end, nomap, &base);
+			if (ret == 0) {
+				pr_debug("Reserved memory: allocated memory for '%s' node: base %pa, size %ld MiB\n",
+					uname, &base,
+					(unsigned long)size / SZ_1M);
+				break;
+			}
+			len -= t_len;
+		}
+
+	} else {
+		ret = early_init_dt_alloc_reserved_memory_arch(size, align,
+							0, 0, nomap, &base);
+		if (ret == 0)
+			pr_debug("Reserved memory: allocated memory for '%s' node: base %pa, size %ld MiB\n",
+				uname, &base, (unsigned long)size / SZ_1M);
+	}
+
+	if (base == 0) {
+		pr_info("Reserved memory: failed to allocate memory for node '%s'\n",
+			uname);
+		return -ENOMEM;
+	}
+
+	*res_base = base;
+	*res_size = size;
+
+	return 0;
+}
+
+static const struct of_device_id __rmem_of_table_sentinel
+	__used __section(__reservedmem_of_table_end);
+
+/**
+ * res_mem_init_node() - call region specific reserved memory init code
+ */
+static int __init __reserved_mem_init_node(struct reserved_mem *rmem)
+{
+	extern const struct of_device_id __reservedmem_of_table[];
+	const struct of_device_id *i;
+
+	for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) {
+		reservedmem_of_init_fn initfn = i->data;
+		const char *compat = i->compatible;
+
+		if (!of_flat_dt_is_compatible(rmem->fdt_node, compat))
+			continue;
+
+		if (initfn(rmem) == 0) {
+			pr_info("Reserved memory: initialized node %s, compatible id %s\n",
+				rmem->name, compat);
+			return 0;
+		}
+	}
+	return -ENOENT;
+}
+
+/**
+ * fdt_init_reserved_mem - allocate and init all saved reserved memory regions
+ */
+void __init fdt_init_reserved_mem(void)
+{
+	int i;
+	for (i = 0; i < reserved_mem_count; i++) {
+		struct reserved_mem *rmem = &reserved_mem[i];
+		unsigned long node = rmem->fdt_node;
+		int len;
+		const __be32 *prop;
+		int err = 0;
+
+		prop = of_get_flat_dt_prop(node, "phandle", &len);
+		if (!prop)
+			prop = of_get_flat_dt_prop(node, "linux,phandle", &len);
+		if (prop)
+			rmem->phandle = of_read_number(prop, len/4);
+
+		if (rmem->size == 0)
+			err = __reserved_mem_alloc_size(node, rmem->name,
+						 &rmem->base, &rmem->size);
+		if (err == 0)
+			__reserved_mem_init_node(rmem);
+	}
+}
+
+static inline struct reserved_mem *__find_rmem(struct device_node *node)
+{
+	unsigned int i;
+
+	if (!node->phandle)
+		return NULL;
+
+	for (i = 0; i < reserved_mem_count; i++)
+		if (reserved_mem[i].phandle == node->phandle)
+			return &reserved_mem[i];
+	return NULL;
+}
+
+/**
+ * of_reserved_mem_device_init() - assign reserved memory region to given device
+ *
+ * This function assign memory region pointed by "memory-region" device tree
+ * property to the given device.
+ */
+int of_reserved_mem_device_init(struct device *dev)
+{
+	struct reserved_mem *rmem;
+	struct device_node *np;
+	int ret;
+
+	np = of_parse_phandle(dev->of_node, "memory-region", 0);
+	if (!np)
+		return -ENODEV;
+
+	rmem = __find_rmem(np);
+	of_node_put(np);
+
+	if (!rmem || !rmem->ops || !rmem->ops->device_init)
+		return -EINVAL;
+
+	ret = rmem->ops->device_init(rmem, dev);
+	if (ret == 0)
+		dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(of_reserved_mem_device_init);
+
+/**
+ * of_reserved_mem_device_release() - release reserved memory device structures
+ *
+ * This function releases structures allocated for memory region handling for
+ * the given device.
+ */
+void of_reserved_mem_device_release(struct device *dev)
+{
+	struct reserved_mem *rmem;
+	struct device_node *np;
+
+	np = of_parse_phandle(dev->of_node, "memory-region", 0);
+	if (!np)
+		return;
+
+	rmem = __find_rmem(np);
+	of_node_put(np);
+
+	if (!rmem || !rmem->ops || !rmem->ops->device_release)
+		return;
+
+	rmem->ops->device_release(rmem, dev);
+}
+EXPORT_SYMBOL_GPL(of_reserved_mem_device_release);
diff --git a/kernel/drivers/of/overlay.c b/kernel/drivers/of/overlay.c
new file mode 100644
index 000000000..dee9270ba
--- /dev/null
+++ b/kernel/drivers/of/overlay.c
@@ -0,0 +1,552 @@
+/*
+ * Functions for working with device tree overlays
+ *
+ * Copyright (C) 2012 Pantelis Antoniou <panto@antoniou-consulting.com>
+ * Copyright (C) 2012 Texas Instruments Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ */
+#undef DEBUG
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/idr.h>
+
+#include "of_private.h"
+
+/**
+ * struct of_overlay_info - Holds a single overlay info
+ * @target:	target of the overlay operation
+ * @overlay:	pointer to the overlay contents node
+ *
+ * Holds a single overlay state, including all the overlay logs &
+ * records.
+ */
+struct of_overlay_info {
+	struct device_node *target;
+	struct device_node *overlay;
+};
+
+/**
+ * struct of_overlay - Holds a complete overlay transaction
+ * @node:	List on which we are located
+ * @count:	Count of ovinfo structures
+ * @ovinfo_tab:	Overlay info table (count sized)
+ * @cset:	Changeset to be used
+ *
+ * Holds a complete overlay transaction
+ */
+struct of_overlay {
+	int id;
+	struct list_head node;
+	int count;
+	struct of_overlay_info *ovinfo_tab;
+	struct of_changeset cset;
+};
+
+static int of_overlay_apply_one(struct of_overlay *ov,
+		struct device_node *target, const struct device_node *overlay);
+
+static int of_overlay_apply_single_property(struct of_overlay *ov,
+		struct device_node *target, struct property *prop)
+{
+	struct property *propn, *tprop;
+
+	/* NOTE: Multiple changes of single properties not supported */
+	tprop = of_find_property(target, prop->name, NULL);
+
+	/* special properties are not meant to be updated (silent NOP) */
+	if (of_prop_cmp(prop->name, "name") == 0 ||
+	    of_prop_cmp(prop->name, "phandle") == 0 ||
+	    of_prop_cmp(prop->name, "linux,phandle") == 0)
+		return 0;
+
+	propn = __of_prop_dup(prop, GFP_KERNEL);
+	if (propn == NULL)
+		return -ENOMEM;
+
+	/* not found? add */
+	if (tprop == NULL)
+		return of_changeset_add_property(&ov->cset, target, propn);
+
+	/* found? update */
+	return of_changeset_update_property(&ov->cset, target, propn);
+}
+
+static int of_overlay_apply_single_device_node(struct of_overlay *ov,
+		struct device_node *target, struct device_node *child)
+{
+	const char *cname;
+	struct device_node *tchild;
+	int ret = 0;
+
+	cname = kbasename(child->full_name);
+	if (cname == NULL)
+		return -ENOMEM;
+
+	/* NOTE: Multiple mods of created nodes not supported */
+	tchild = of_get_child_by_name(target, cname);
+	if (tchild != NULL) {
+		/* apply overlay recursively */
+		ret = of_overlay_apply_one(ov, tchild, child);
+		of_node_put(tchild);
+	} else {
+		/* create empty tree as a target */
+		tchild = __of_node_dup(child, "%s/%s", target->full_name, cname);
+		if (!tchild)
+			return -ENOMEM;
+
+		/* point to parent */
+		tchild->parent = target;
+
+		ret = of_changeset_attach_node(&ov->cset, tchild);
+		if (ret)
+			return ret;
+
+		ret = of_overlay_apply_one(ov, tchild, child);
+		if (ret)
+			return ret;
+	}
+
+	return ret;
+}
+
+/*
+ * Apply a single overlay node recursively.
+ *
+ * Note that the in case of an error the target node is left
+ * in a inconsistent state. Error recovery should be performed
+ * by using the changeset.
+ */
+static int of_overlay_apply_one(struct of_overlay *ov,
+		struct device_node *target, const struct device_node *overlay)
+{
+	struct device_node *child;
+	struct property *prop;
+	int ret;
+
+	for_each_property_of_node(overlay, prop) {
+		ret = of_overlay_apply_single_property(ov, target, prop);
+		if (ret) {
+			pr_err("%s: Failed to apply prop @%s/%s\n",
+				__func__, target->full_name, prop->name);
+			return ret;
+		}
+	}
+
+	for_each_child_of_node(overlay, child) {
+		ret = of_overlay_apply_single_device_node(ov, target, child);
+		if (ret != 0) {
+			pr_err("%s: Failed to apply single node @%s/%s\n",
+					__func__, target->full_name,
+					child->name);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * of_overlay_apply() - Apply @count overlays pointed at by @ovinfo_tab
+ * @ov:		Overlay to apply
+ *
+ * Applies the overlays given, while handling all error conditions
+ * appropriately. Either the operation succeeds, or if it fails the
+ * live tree is reverted to the state before the attempt.
+ * Returns 0, or an error if the overlay attempt failed.
+ */
+static int of_overlay_apply(struct of_overlay *ov)
+{
+	int i, err;
+
+	/* first we apply the overlays atomically */
+	for (i = 0; i < ov->count; i++) {
+		struct of_overlay_info *ovinfo = &ov->ovinfo_tab[i];
+
+		err = of_overlay_apply_one(ov, ovinfo->target, ovinfo->overlay);
+		if (err != 0) {
+			pr_err("%s: overlay failed '%s'\n",
+				__func__, ovinfo->target->full_name);
+			return err;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * Find the target node using a number of different strategies
+ * in order of preference
+ *
+ * "target" property containing the phandle of the target
+ * "target-path" property containing the path of the target
+ */
+static struct device_node *find_target_node(struct device_node *info_node)
+{
+	const char *path;
+	u32 val;
+	int ret;
+
+	/* first try to go by using the target as a phandle */
+	ret = of_property_read_u32(info_node, "target", &val);
+	if (ret == 0)
+		return of_find_node_by_phandle(val);
+
+	/* now try to locate by path */
+	ret = of_property_read_string(info_node, "target-path", &path);
+	if (ret == 0)
+		return of_find_node_by_path(path);
+
+	pr_err("%s: Failed to find target for node %p (%s)\n", __func__,
+		info_node, info_node->name);
+
+	return NULL;
+}
+
+/**
+ * of_fill_overlay_info() - Fill an overlay info structure
+ * @ov		Overlay to fill
+ * @info_node:	Device node containing the overlay
+ * @ovinfo:	Pointer to the overlay info structure to fill
+ *
+ * Fills an overlay info structure with the overlay information
+ * from a device node. This device node must have a target property
+ * which contains a phandle of the overlay target node, and an
+ * __overlay__ child node which has the overlay contents.
+ * Both ovinfo->target & ovinfo->overlay have their references taken.
+ *
+ * Returns 0 on success, or a negative error value.
+ */
+static int of_fill_overlay_info(struct of_overlay *ov,
+		struct device_node *info_node, struct of_overlay_info *ovinfo)
+{
+	ovinfo->overlay = of_get_child_by_name(info_node, "__overlay__");
+	if (ovinfo->overlay == NULL)
+		goto err_fail;
+
+	ovinfo->target = find_target_node(info_node);
+	if (ovinfo->target == NULL)
+		goto err_fail;
+
+	return 0;
+
+err_fail:
+	of_node_put(ovinfo->target);
+	of_node_put(ovinfo->overlay);
+
+	memset(ovinfo, 0, sizeof(*ovinfo));
+	return -EINVAL;
+}
+
+/**
+ * of_build_overlay_info() - Build an overlay info array
+ * @ov		Overlay to build
+ * @tree:	Device node containing all the overlays
+ *
+ * Helper function that given a tree containing overlay information,
+ * allocates and builds an overlay info array containing it, ready
+ * for use using of_overlay_apply.
+ *
+ * Returns 0 on success with the @cntp @ovinfop pointers valid,
+ * while on error a negative error value is returned.
+ */
+static int of_build_overlay_info(struct of_overlay *ov,
+		struct device_node *tree)
+{
+	struct device_node *node;
+	struct of_overlay_info *ovinfo;
+	int cnt, err;
+
+	/* worst case; every child is a node */
+	cnt = 0;
+	for_each_child_of_node(tree, node)
+		cnt++;
+
+	ovinfo = kcalloc(cnt, sizeof(*ovinfo), GFP_KERNEL);
+	if (ovinfo == NULL)
+		return -ENOMEM;
+
+	cnt = 0;
+	for_each_child_of_node(tree, node) {
+		memset(&ovinfo[cnt], 0, sizeof(*ovinfo));
+		err = of_fill_overlay_info(ov, node, &ovinfo[cnt]);
+		if (err == 0)
+			cnt++;
+	}
+
+	/* if nothing filled, return error */
+	if (cnt == 0) {
+		kfree(ovinfo);
+		return -ENODEV;
+	}
+
+	ov->count = cnt;
+	ov->ovinfo_tab = ovinfo;
+
+	return 0;
+}
+
+/**
+ * of_free_overlay_info() - Free an overlay info array
+ * @ov		Overlay to free the overlay info from
+ * @ovinfo_tab:	Array of overlay_info's to free
+ *
+ * Releases the memory of a previously allocated ovinfo array
+ * by of_build_overlay_info.
+ * Returns 0, or an error if the arguments are bogus.
+ */
+static int of_free_overlay_info(struct of_overlay *ov)
+{
+	struct of_overlay_info *ovinfo;
+	int i;
+
+	/* do it in reverse */
+	for (i = ov->count - 1; i >= 0; i--) {
+		ovinfo = &ov->ovinfo_tab[i];
+
+		of_node_put(ovinfo->target);
+		of_node_put(ovinfo->overlay);
+	}
+	kfree(ov->ovinfo_tab);
+
+	return 0;
+}
+
+static LIST_HEAD(ov_list);
+static DEFINE_IDR(ov_idr);
+
+/**
+ * of_overlay_create() - Create and apply an overlay
+ * @tree:	Device node containing all the overlays
+ *
+ * Creates and applies an overlay while also keeping track
+ * of the overlay in a list. This list can be used to prevent
+ * illegal overlay removals.
+ *
+ * Returns the id of the created overlay, or an negative error number
+ */
+int of_overlay_create(struct device_node *tree)
+{
+	struct of_overlay *ov;
+	int err, id;
+
+	/* allocate the overlay structure */
+	ov = kzalloc(sizeof(*ov), GFP_KERNEL);
+	if (ov == NULL)
+		return -ENOMEM;
+	ov->id = -1;
+
+	INIT_LIST_HEAD(&ov->node);
+
+	of_changeset_init(&ov->cset);
+
+	mutex_lock(&of_mutex);
+
+	id = idr_alloc(&ov_idr, ov, 0, 0, GFP_KERNEL);
+	if (id < 0) {
+		pr_err("%s: idr_alloc() failed for tree@%s\n",
+				__func__, tree->full_name);
+		err = id;
+		goto err_destroy_trans;
+	}
+	ov->id = id;
+
+	/* build the overlay info structures */
+	err = of_build_overlay_info(ov, tree);
+	if (err) {
+		pr_err("%s: of_build_overlay_info() failed for tree@%s\n",
+				__func__, tree->full_name);
+		goto err_free_idr;
+	}
+
+	/* apply the overlay */
+	err = of_overlay_apply(ov);
+	if (err) {
+		pr_err("%s: of_overlay_apply() failed for tree@%s\n",
+				__func__, tree->full_name);
+		goto err_abort_trans;
+	}
+
+	/* apply the changeset */
+	err = of_changeset_apply(&ov->cset);
+	if (err) {
+		pr_err("%s: of_changeset_apply() failed for tree@%s\n",
+				__func__, tree->full_name);
+		goto err_revert_overlay;
+	}
+
+	/* add to the tail of the overlay list */
+	list_add_tail(&ov->node, &ov_list);
+
+	mutex_unlock(&of_mutex);
+
+	return id;
+
+err_revert_overlay:
+err_abort_trans:
+	of_free_overlay_info(ov);
+err_free_idr:
+	idr_remove(&ov_idr, ov->id);
+err_destroy_trans:
+	of_changeset_destroy(&ov->cset);
+	kfree(ov);
+	mutex_unlock(&of_mutex);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(of_overlay_create);
+
+/* check whether the given node, lies under the given tree */
+static int overlay_subtree_check(struct device_node *tree,
+		struct device_node *dn)
+{
+	struct device_node *child;
+
+	/* match? */
+	if (tree == dn)
+		return 1;
+
+	for_each_child_of_node(tree, child) {
+		if (overlay_subtree_check(child, dn))
+			return 1;
+	}
+
+	return 0;
+}
+
+/* check whether this overlay is the topmost */
+static int overlay_is_topmost(struct of_overlay *ov, struct device_node *dn)
+{
+	struct of_overlay *ovt;
+	struct of_changeset_entry *ce;
+
+	list_for_each_entry_reverse(ovt, &ov_list, node) {
+		/* if we hit ourselves, we're done */
+		if (ovt == ov)
+			break;
+
+		/* check against each subtree affected by this overlay */
+		list_for_each_entry(ce, &ovt->cset.entries, node) {
+			if (overlay_subtree_check(ce->np, dn)) {
+				pr_err("%s: #%d clashes #%d @%s\n",
+					__func__, ov->id, ovt->id,
+					dn->full_name);
+				return 0;
+			}
+		}
+	}
+
+	/* overlay is topmost */
+	return 1;
+}
+
+/*
+ * We can safely remove the overlay only if it's the top-most one.
+ * Newly applied overlays are inserted at the tail of the overlay list,
+ * so a top most overlay is the one that is closest to the tail.
+ *
+ * The topmost check is done by exploiting this property. For each
+ * affected device node in the log list we check if this overlay is
+ * the one closest to the tail. If another overlay has affected this
+ * device node and is closest to the tail, then removal is not permited.
+ */
+static int overlay_removal_is_ok(struct of_overlay *ov)
+{
+	struct of_changeset_entry *ce;
+
+	list_for_each_entry(ce, &ov->cset.entries, node) {
+		if (!overlay_is_topmost(ov, ce->np)) {
+			pr_err("%s: overlay #%d is not topmost\n",
+					__func__, ov->id);
+			return 0;
+		}
+	}
+
+	return 1;
+}
+
+/**
+ * of_overlay_destroy() - Removes an overlay
+ * @id:	Overlay id number returned by a previous call to of_overlay_create
+ *
+ * Removes an overlay if it is permissible.
+ *
+ * Returns 0 on success, or an negative error number
+ */
+int of_overlay_destroy(int id)
+{
+	struct of_overlay *ov;
+	int err;
+
+	mutex_lock(&of_mutex);
+
+	ov = idr_find(&ov_idr, id);
+	if (ov == NULL) {
+		err = -ENODEV;
+		pr_err("%s: Could not find overlay #%d\n",
+				__func__, id);
+		goto out;
+	}
+
+	/* check whether the overlay is safe to remove */
+	if (!overlay_removal_is_ok(ov)) {
+		err = -EBUSY;
+		pr_err("%s: removal check failed for overlay #%d\n",
+				__func__, id);
+		goto out;
+	}
+
+
+	list_del(&ov->node);
+	of_changeset_revert(&ov->cset);
+	of_free_overlay_info(ov);
+	idr_remove(&ov_idr, id);
+	of_changeset_destroy(&ov->cset);
+	kfree(ov);
+
+	err = 0;
+
+out:
+	mutex_unlock(&of_mutex);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(of_overlay_destroy);
+
+/**
+ * of_overlay_destroy_all() - Removes all overlays from the system
+ *
+ * Removes all overlays from the system in the correct order.
+ *
+ * Returns 0 on success, or an negative error number
+ */
+int of_overlay_destroy_all(void)
+{
+	struct of_overlay *ov, *ovn;
+
+	mutex_lock(&of_mutex);
+
+	/* the tail of list is guaranteed to be safe to remove */
+	list_for_each_entry_safe_reverse(ov, ovn, &ov_list, node) {
+		list_del(&ov->node);
+		of_changeset_revert(&ov->cset);
+		of_free_overlay_info(ov);
+		idr_remove(&ov_idr, ov->id);
+		kfree(ov);
+	}
+
+	mutex_unlock(&of_mutex);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_overlay_destroy_all);
diff --git a/kernel/drivers/of/pdt.c b/kernel/drivers/of/pdt.c
new file mode 100644
index 000000000..d2acae825
--- /dev/null
+++ b/kernel/drivers/of/pdt.c
@@ -0,0 +1,245 @@
+/* pdt.c: OF PROM device tree support code.
+ *
+ * Paul Mackerras	August 1996.
+ * Copyright (C) 1996-2005 Paul Mackerras.
+ *
+ *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
+ *    {engebret|bergner}@us.ibm.com
+ *
+ *  Adapted for sparc by David S. Miller davem@davemloft.net
+ *  Adapted for multiple architectures by Andres Salomon <dilinger@queued.net>
+ *
+ *      This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_pdt.h>
+
+static struct of_pdt_ops *of_pdt_prom_ops __initdata;
+
+void __initdata (*of_pdt_build_more)(struct device_node *dp);
+
+#if defined(CONFIG_SPARC)
+unsigned int of_pdt_unique_id __initdata;
+
+#define of_pdt_incr_unique_id(p) do { \
+	(p)->unique_id = of_pdt_unique_id++; \
+} while (0)
+
+static char * __init of_pdt_build_full_name(struct device_node *dp)
+{
+	int len, ourlen, plen;
+	char *n;
+
+	dp->path_component_name = build_path_component(dp);
+
+	plen = strlen(dp->parent->full_name);
+	ourlen = strlen(dp->path_component_name);
+	len = ourlen + plen + 2;
+
+	n = prom_early_alloc(len);
+	strcpy(n, dp->parent->full_name);
+	if (!of_node_is_root(dp->parent)) {
+		strcpy(n + plen, "/");
+		plen++;
+	}
+	strcpy(n + plen, dp->path_component_name);
+
+	return n;
+}
+
+#else /* CONFIG_SPARC */
+
+static inline void of_pdt_incr_unique_id(void *p) { }
+static inline void irq_trans_init(struct device_node *dp) { }
+
+static char * __init of_pdt_build_full_name(struct device_node *dp)
+{
+	static int failsafe_id = 0; /* for generating unique names on failure */
+	char *buf;
+	int len;
+
+	if (of_pdt_prom_ops->pkg2path(dp->phandle, NULL, 0, &len))
+		goto failsafe;
+
+	buf = prom_early_alloc(len + 1);
+	if (of_pdt_prom_ops->pkg2path(dp->phandle, buf, len, &len))
+		goto failsafe;
+	return buf;
+
+ failsafe:
+	buf = prom_early_alloc(strlen(dp->parent->full_name) +
+			       strlen(dp->name) + 16);
+	sprintf(buf, "%s/%s@unknown%i",
+		of_node_is_root(dp->parent) ? "" : dp->parent->full_name,
+		dp->name, failsafe_id++);
+	pr_err("%s: pkg2path failed; assigning %s\n", __func__, buf);
+	return buf;
+}
+
+#endif /* !CONFIG_SPARC */
+
+static struct property * __init of_pdt_build_one_prop(phandle node, char *prev,
+					       char *special_name,
+					       void *special_val,
+					       int special_len)
+{
+	static struct property *tmp = NULL;
+	struct property *p;
+	int err;
+
+	if (tmp) {
+		p = tmp;
+		memset(p, 0, sizeof(*p) + 32);
+		tmp = NULL;
+	} else {
+		p = prom_early_alloc(sizeof(struct property) + 32);
+		of_pdt_incr_unique_id(p);
+	}
+
+	p->name = (char *) (p + 1);
+	if (special_name) {
+		strcpy(p->name, special_name);
+		p->length = special_len;
+		p->value = prom_early_alloc(special_len);
+		memcpy(p->value, special_val, special_len);
+	} else {
+		err = of_pdt_prom_ops->nextprop(node, prev, p->name);
+		if (err) {
+			tmp = p;
+			return NULL;
+		}
+		p->length = of_pdt_prom_ops->getproplen(node, p->name);
+		if (p->length <= 0) {
+			p->length = 0;
+		} else {
+			int len;
+
+			p->value = prom_early_alloc(p->length + 1);
+			len = of_pdt_prom_ops->getproperty(node, p->name,
+					p->value, p->length);
+			if (len <= 0)
+				p->length = 0;
+			((unsigned char *)p->value)[p->length] = '\0';
+		}
+	}
+	return p;
+}
+
+static struct property * __init of_pdt_build_prop_list(phandle node)
+{
+	struct property *head, *tail;
+
+	head = tail = of_pdt_build_one_prop(node, NULL,
+				     ".node", &node, sizeof(node));
+
+	tail->next = of_pdt_build_one_prop(node, NULL, NULL, NULL, 0);
+	tail = tail->next;
+	while(tail) {
+		tail->next = of_pdt_build_one_prop(node, tail->name,
+					    NULL, NULL, 0);
+		tail = tail->next;
+	}
+
+	return head;
+}
+
+static char * __init of_pdt_get_one_property(phandle node, const char *name)
+{
+	char *buf = "<NULL>";
+	int len;
+
+	len = of_pdt_prom_ops->getproplen(node, name);
+	if (len > 0) {
+		buf = prom_early_alloc(len);
+		len = of_pdt_prom_ops->getproperty(node, name, buf, len);
+	}
+
+	return buf;
+}
+
+static struct device_node * __init of_pdt_create_node(phandle node,
+						    struct device_node *parent)
+{
+	struct device_node *dp;
+
+	if (!node)
+		return NULL;
+
+	dp = prom_early_alloc(sizeof(*dp));
+	of_node_init(dp);
+	of_pdt_incr_unique_id(dp);
+	dp->parent = parent;
+
+	dp->name = of_pdt_get_one_property(node, "name");
+	dp->type = of_pdt_get_one_property(node, "device_type");
+	dp->phandle = node;
+
+	dp->properties = of_pdt_build_prop_list(node);
+
+	irq_trans_init(dp);
+
+	return dp;
+}
+
+static struct device_node * __init of_pdt_build_tree(struct device_node *parent,
+						   phandle node)
+{
+	struct device_node *ret = NULL, *prev_sibling = NULL;
+	struct device_node *dp;
+
+	while (1) {
+		dp = of_pdt_create_node(node, parent);
+		if (!dp)
+			break;
+
+		if (prev_sibling)
+			prev_sibling->sibling = dp;
+
+		if (!ret)
+			ret = dp;
+		prev_sibling = dp;
+
+		dp->full_name = of_pdt_build_full_name(dp);
+
+		dp->child = of_pdt_build_tree(dp, of_pdt_prom_ops->getchild(node));
+
+		if (of_pdt_build_more)
+			of_pdt_build_more(dp);
+
+		node = of_pdt_prom_ops->getsibling(node);
+	}
+
+	return ret;
+}
+
+static void * __init kernel_tree_alloc(u64 size, u64 align)
+{
+	return prom_early_alloc(size);
+}
+
+void __init of_pdt_build_devicetree(phandle root_node, struct of_pdt_ops *ops)
+{
+	BUG_ON(!ops);
+	of_pdt_prom_ops = ops;
+
+	of_root = of_pdt_create_node(root_node, NULL);
+#if defined(CONFIG_SPARC)
+	of_root->path_component_name = "";
+#endif
+	of_root->full_name = "/";
+
+	of_root->child = of_pdt_build_tree(of_root,
+				of_pdt_prom_ops->getchild(of_root->phandle));
+
+	/* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
+	of_alias_scan(kernel_tree_alloc);
+}
diff --git a/kernel/drivers/of/platform.c b/kernel/drivers/of/platform.c
new file mode 100644
index 000000000..a01f57c9e
--- /dev/null
+++ b/kernel/drivers/of/platform.c
@@ -0,0 +1,566 @@
+/*
+ *    Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
+ *			 <benh@kernel.crashing.org>
+ *    and		 Arnd Bergmann, IBM Corp.
+ *    Merged from powerpc/kernel/of_platform.c and
+ *    sparc{,64}/kernel/of_device.c by Stephen Rothwell
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ *
+ */
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/amba/bus.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+
+const struct of_device_id of_default_bus_match_table[] = {
+	{ .compatible = "simple-bus", },
+#ifdef CONFIG_ARM_AMBA
+	{ .compatible = "arm,amba-bus", },
+#endif /* CONFIG_ARM_AMBA */
+	{} /* Empty terminated list */
+};
+
+static int of_dev_node_match(struct device *dev, void *data)
+{
+	return dev->of_node == data;
+}
+
+/**
+ * of_find_device_by_node - Find the platform_device associated with a node
+ * @np: Pointer to device tree node
+ *
+ * Returns platform_device pointer, or NULL if not found
+ */
+struct platform_device *of_find_device_by_node(struct device_node *np)
+{
+	struct device *dev;
+
+	dev = bus_find_device(&platform_bus_type, NULL, np, of_dev_node_match);
+	return dev ? to_platform_device(dev) : NULL;
+}
+EXPORT_SYMBOL(of_find_device_by_node);
+
+#ifdef CONFIG_OF_ADDRESS
+/*
+ * The following routines scan a subtree and registers a device for
+ * each applicable node.
+ *
+ * Note: sparc doesn't use these routines because it has a different
+ * mechanism for creating devices from device tree nodes.
+ */
+
+/**
+ * of_device_make_bus_id - Use the device node data to assign a unique name
+ * @dev: pointer to device structure that is linked to a device tree node
+ *
+ * This routine will first try using the translated bus address to
+ * derive a unique name. If it cannot, then it will prepend names from
+ * parent nodes until a unique name can be derived.
+ */
+void of_device_make_bus_id(struct device *dev)
+{
+	struct device_node *node = dev->of_node;
+	const __be32 *reg;
+	u64 addr;
+
+	/* Construct the name, using parent nodes if necessary to ensure uniqueness */
+	while (node->parent) {
+		/*
+		 * If the address can be translated, then that is as much
+		 * uniqueness as we need. Make it the first component and return
+		 */
+		reg = of_get_property(node, "reg", NULL);
+		if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) {
+			dev_set_name(dev, dev_name(dev) ? "%llx.%s:%s" : "%llx.%s",
+				     (unsigned long long)addr, node->name,
+				     dev_name(dev));
+			return;
+		}
+
+		/* format arguments only used if dev_name() resolves to NULL */
+		dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s",
+			     strrchr(node->full_name, '/') + 1, dev_name(dev));
+		node = node->parent;
+	}
+}
+
+/**
+ * of_device_alloc - Allocate and initialize an of_device
+ * @np: device node to assign to device
+ * @bus_id: Name to assign to the device.  May be null to use default name.
+ * @parent: Parent device.
+ */
+struct platform_device *of_device_alloc(struct device_node *np,
+				  const char *bus_id,
+				  struct device *parent)
+{
+	struct platform_device *dev;
+	int rc, i, num_reg = 0, num_irq;
+	struct resource *res, temp_res;
+
+	dev = platform_device_alloc("", -1);
+	if (!dev)
+		return NULL;
+
+	/* count the io and irq resources */
+	while (of_address_to_resource(np, num_reg, &temp_res) == 0)
+		num_reg++;
+	num_irq = of_irq_count(np);
+
+	/* Populate the resource table */
+	if (num_irq || num_reg) {
+		res = kzalloc(sizeof(*res) * (num_irq + num_reg), GFP_KERNEL);
+		if (!res) {
+			platform_device_put(dev);
+			return NULL;
+		}
+
+		dev->num_resources = num_reg + num_irq;
+		dev->resource = res;
+		for (i = 0; i < num_reg; i++, res++) {
+			rc = of_address_to_resource(np, i, res);
+			WARN_ON(rc);
+		}
+		if (of_irq_to_resource_table(np, res, num_irq) != num_irq)
+			pr_debug("not all legacy IRQ resources mapped for %s\n",
+				 np->name);
+	}
+
+	dev->dev.of_node = of_node_get(np);
+	dev->dev.parent = parent ? : &platform_bus;
+
+	if (bus_id)
+		dev_set_name(&dev->dev, "%s", bus_id);
+	else
+		of_device_make_bus_id(&dev->dev);
+
+	return dev;
+}
+EXPORT_SYMBOL(of_device_alloc);
+
+static void of_dma_deconfigure(struct device *dev)
+{
+	arch_teardown_dma_ops(dev);
+}
+
+/**
+ * of_platform_device_create_pdata - Alloc, initialize and register an of_device
+ * @np: pointer to node to create device for
+ * @bus_id: name to assign device
+ * @platform_data: pointer to populate platform_data pointer with
+ * @parent: Linux device model parent device.
+ *
+ * Returns pointer to created platform device, or NULL if a device was not
+ * registered.  Unavailable devices will not get registered.
+ */
+static struct platform_device *of_platform_device_create_pdata(
+					struct device_node *np,
+					const char *bus_id,
+					void *platform_data,
+					struct device *parent)
+{
+	struct platform_device *dev;
+
+	if (!of_device_is_available(np) ||
+	    of_node_test_and_set_flag(np, OF_POPULATED))
+		return NULL;
+
+	dev = of_device_alloc(np, bus_id, parent);
+	if (!dev)
+		goto err_clear_flag;
+
+	dev->dev.bus = &platform_bus_type;
+	dev->dev.platform_data = platform_data;
+	of_dma_configure(&dev->dev, dev->dev.of_node);
+
+	if (of_device_add(dev) != 0) {
+		of_dma_deconfigure(&dev->dev);
+		platform_device_put(dev);
+		goto err_clear_flag;
+	}
+
+	return dev;
+
+err_clear_flag:
+	of_node_clear_flag(np, OF_POPULATED);
+	return NULL;
+}
+
+/**
+ * of_platform_device_create - Alloc, initialize and register an of_device
+ * @np: pointer to node to create device for
+ * @bus_id: name to assign device
+ * @parent: Linux device model parent device.
+ *
+ * Returns pointer to created platform device, or NULL if a device was not
+ * registered.  Unavailable devices will not get registered.
+ */
+struct platform_device *of_platform_device_create(struct device_node *np,
+					    const char *bus_id,
+					    struct device *parent)
+{
+	return of_platform_device_create_pdata(np, bus_id, NULL, parent);
+}
+EXPORT_SYMBOL(of_platform_device_create);
+
+#ifdef CONFIG_ARM_AMBA
+static struct amba_device *of_amba_device_create(struct device_node *node,
+						 const char *bus_id,
+						 void *platform_data,
+						 struct device *parent)
+{
+	struct amba_device *dev;
+	const void *prop;
+	int i, ret;
+
+	pr_debug("Creating amba device %s\n", node->full_name);
+
+	if (!of_device_is_available(node) ||
+	    of_node_test_and_set_flag(node, OF_POPULATED))
+		return NULL;
+
+	dev = amba_device_alloc(NULL, 0, 0);
+	if (!dev) {
+		pr_err("%s(): amba_device_alloc() failed for %s\n",
+		       __func__, node->full_name);
+		goto err_clear_flag;
+	}
+
+	/* setup generic device info */
+	dev->dev.of_node = of_node_get(node);
+	dev->dev.parent = parent ? : &platform_bus;
+	dev->dev.platform_data = platform_data;
+	if (bus_id)
+		dev_set_name(&dev->dev, "%s", bus_id);
+	else
+		of_device_make_bus_id(&dev->dev);
+	of_dma_configure(&dev->dev, dev->dev.of_node);
+
+	/* Allow the HW Peripheral ID to be overridden */
+	prop = of_get_property(node, "arm,primecell-periphid", NULL);
+	if (prop)
+		dev->periphid = of_read_ulong(prop, 1);
+
+	/* Decode the IRQs and address ranges */
+	for (i = 0; i < AMBA_NR_IRQS; i++)
+		dev->irq[i] = irq_of_parse_and_map(node, i);
+
+	ret = of_address_to_resource(node, 0, &dev->res);
+	if (ret) {
+		pr_err("%s(): of_address_to_resource() failed (%d) for %s\n",
+		       __func__, ret, node->full_name);
+		goto err_free;
+	}
+
+	ret = amba_device_add(dev, &iomem_resource);
+	if (ret) {
+		pr_err("%s(): amba_device_add() failed (%d) for %s\n",
+		       __func__, ret, node->full_name);
+		goto err_free;
+	}
+
+	return dev;
+
+err_free:
+	amba_device_put(dev);
+err_clear_flag:
+	of_node_clear_flag(node, OF_POPULATED);
+	return NULL;
+}
+#else /* CONFIG_ARM_AMBA */
+static struct amba_device *of_amba_device_create(struct device_node *node,
+						 const char *bus_id,
+						 void *platform_data,
+						 struct device *parent)
+{
+	return NULL;
+}
+#endif /* CONFIG_ARM_AMBA */
+
+/**
+ * of_devname_lookup() - Given a device node, lookup the preferred Linux name
+ */
+static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
+				 struct device_node *np)
+{
+	struct resource res;
+
+	if (!lookup)
+		return NULL;
+
+	for(; lookup->compatible != NULL; lookup++) {
+		if (!of_device_is_compatible(np, lookup->compatible))
+			continue;
+		if (!of_address_to_resource(np, 0, &res))
+			if (res.start != lookup->phys_addr)
+				continue;
+		pr_debug("%s: devname=%s\n", np->full_name, lookup->name);
+		return lookup;
+	}
+
+	return NULL;
+}
+
+/**
+ * of_platform_bus_create() - Create a device for a node and its children.
+ * @bus: device node of the bus to instantiate
+ * @matches: match table for bus nodes
+ * @lookup: auxdata table for matching id and platform_data with device nodes
+ * @parent: parent for new device, or NULL for top level.
+ * @strict: require compatible property
+ *
+ * Creates a platform_device for the provided device_node, and optionally
+ * recursively create devices for all the child nodes.
+ */
+static int of_platform_bus_create(struct device_node *bus,
+				  const struct of_device_id *matches,
+				  const struct of_dev_auxdata *lookup,
+				  struct device *parent, bool strict)
+{
+	const struct of_dev_auxdata *auxdata;
+	struct device_node *child;
+	struct platform_device *dev;
+	const char *bus_id = NULL;
+	void *platform_data = NULL;
+	int rc = 0;
+
+	/* Make sure it has a compatible property */
+	if (strict && (!of_get_property(bus, "compatible", NULL))) {
+		pr_debug("%s() - skipping %s, no compatible prop\n",
+			 __func__, bus->full_name);
+		return 0;
+	}
+
+	auxdata = of_dev_lookup(lookup, bus);
+	if (auxdata) {
+		bus_id = auxdata->name;
+		platform_data = auxdata->platform_data;
+	}
+
+	if (of_device_is_compatible(bus, "arm,primecell")) {
+		/*
+		 * Don't return an error here to keep compatibility with older
+		 * device tree files.
+		 */
+		of_amba_device_create(bus, bus_id, platform_data, parent);
+		return 0;
+	}
+
+	dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
+	if (!dev || !of_match_node(matches, bus))
+		return 0;
+
+	for_each_child_of_node(bus, child) {
+		pr_debug("   create child: %s\n", child->full_name);
+		rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
+		if (rc) {
+			of_node_put(child);
+			break;
+		}
+	}
+	of_node_set_flag(bus, OF_POPULATED_BUS);
+	return rc;
+}
+
+/**
+ * of_platform_bus_probe() - Probe the device-tree for platform buses
+ * @root: parent of the first level to probe or NULL for the root of the tree
+ * @matches: match table for bus nodes
+ * @parent: parent to hook devices from, NULL for toplevel
+ *
+ * Note that children of the provided root are not instantiated as devices
+ * unless the specified root itself matches the bus list and is not NULL.
+ */
+int of_platform_bus_probe(struct device_node *root,
+			  const struct of_device_id *matches,
+			  struct device *parent)
+{
+	struct device_node *child;
+	int rc = 0;
+
+	root = root ? of_node_get(root) : of_find_node_by_path("/");
+	if (!root)
+		return -EINVAL;
+
+	pr_debug("of_platform_bus_probe()\n");
+	pr_debug(" starting at: %s\n", root->full_name);
+
+	/* Do a self check of bus type, if there's a match, create children */
+	if (of_match_node(matches, root)) {
+		rc = of_platform_bus_create(root, matches, NULL, parent, false);
+	} else for_each_child_of_node(root, child) {
+		if (!of_match_node(matches, child))
+			continue;
+		rc = of_platform_bus_create(child, matches, NULL, parent, false);
+		if (rc)
+			break;
+	}
+
+	of_node_put(root);
+	return rc;
+}
+EXPORT_SYMBOL(of_platform_bus_probe);
+
+/**
+ * of_platform_populate() - Populate platform_devices from device tree data
+ * @root: parent of the first level to probe or NULL for the root of the tree
+ * @matches: match table, NULL to use the default
+ * @lookup: auxdata table for matching id and platform_data with device nodes
+ * @parent: parent to hook devices from, NULL for toplevel
+ *
+ * Similar to of_platform_bus_probe(), this function walks the device tree
+ * and creates devices from nodes.  It differs in that it follows the modern
+ * convention of requiring all device nodes to have a 'compatible' property,
+ * and it is suitable for creating devices which are children of the root
+ * node (of_platform_bus_probe will only create children of the root which
+ * are selected by the @matches argument).
+ *
+ * New board support should be using this function instead of
+ * of_platform_bus_probe().
+ *
+ * Returns 0 on success, < 0 on failure.
+ */
+int of_platform_populate(struct device_node *root,
+			const struct of_device_id *matches,
+			const struct of_dev_auxdata *lookup,
+			struct device *parent)
+{
+	struct device_node *child;
+	int rc = 0;
+
+	root = root ? of_node_get(root) : of_find_node_by_path("/");
+	if (!root)
+		return -EINVAL;
+
+	for_each_child_of_node(root, child) {
+		rc = of_platform_bus_create(child, matches, lookup, parent, true);
+		if (rc)
+			break;
+	}
+	of_node_set_flag(root, OF_POPULATED_BUS);
+
+	of_node_put(root);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(of_platform_populate);
+
+static int of_platform_device_destroy(struct device *dev, void *data)
+{
+	/* Do not touch devices not populated from the device tree */
+	if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED))
+		return 0;
+
+	/* Recurse for any nodes that were treated as busses */
+	if (of_node_check_flag(dev->of_node, OF_POPULATED_BUS))
+		device_for_each_child(dev, NULL, of_platform_device_destroy);
+
+	if (dev->bus == &platform_bus_type)
+		platform_device_unregister(to_platform_device(dev));
+#ifdef CONFIG_ARM_AMBA
+	else if (dev->bus == &amba_bustype)
+		amba_device_unregister(to_amba_device(dev));
+#endif
+
+	of_dma_deconfigure(dev);
+	of_node_clear_flag(dev->of_node, OF_POPULATED);
+	of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
+	return 0;
+}
+
+/**
+ * of_platform_depopulate() - Remove devices populated from device tree
+ * @parent: device which children will be removed
+ *
+ * Complementary to of_platform_populate(), this function removes children
+ * of the given device (and, recurrently, their children) that have been
+ * created from their respective device tree nodes (and only those,
+ * leaving others - eg. manually created - unharmed).
+ *
+ * Returns 0 when all children devices have been removed or
+ * -EBUSY when some children remained.
+ */
+void of_platform_depopulate(struct device *parent)
+{
+	if (parent->of_node && of_node_check_flag(parent->of_node, OF_POPULATED_BUS)) {
+		device_for_each_child(parent, NULL, of_platform_device_destroy);
+		of_node_clear_flag(parent->of_node, OF_POPULATED_BUS);
+	}
+}
+EXPORT_SYMBOL_GPL(of_platform_depopulate);
+
+#ifdef CONFIG_OF_DYNAMIC
+static int of_platform_notify(struct notifier_block *nb,
+				unsigned long action, void *arg)
+{
+	struct of_reconfig_data *rd = arg;
+	struct platform_device *pdev_parent, *pdev;
+	bool children_left;
+
+	switch (of_reconfig_get_state_change(action, rd)) {
+	case OF_RECONFIG_CHANGE_ADD:
+		/* verify that the parent is a bus */
+		if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS))
+			return NOTIFY_OK;	/* not for us */
+
+		/* already populated? (driver using of_populate manually) */
+		if (of_node_check_flag(rd->dn, OF_POPULATED))
+			return NOTIFY_OK;
+
+		/* pdev_parent may be NULL when no bus platform device */
+		pdev_parent = of_find_device_by_node(rd->dn->parent);
+		pdev = of_platform_device_create(rd->dn, NULL,
+				pdev_parent ? &pdev_parent->dev : NULL);
+		of_dev_put(pdev_parent);
+
+		if (pdev == NULL) {
+			pr_err("%s: failed to create for '%s'\n",
+					__func__, rd->dn->full_name);
+			/* of_platform_device_create tosses the error code */
+			return notifier_from_errno(-EINVAL);
+		}
+		break;
+
+	case OF_RECONFIG_CHANGE_REMOVE:
+
+		/* already depopulated? */
+		if (!of_node_check_flag(rd->dn, OF_POPULATED))
+			return NOTIFY_OK;
+
+		/* find our device by node */
+		pdev = of_find_device_by_node(rd->dn);
+		if (pdev == NULL)
+			return NOTIFY_OK;	/* no? not meant for us */
+
+		/* unregister takes one ref away */
+		of_platform_device_destroy(&pdev->dev, &children_left);
+
+		/* and put the reference of the find */
+		of_dev_put(pdev);
+		break;
+	}
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block platform_of_notifier = {
+	.notifier_call = of_platform_notify,
+};
+
+void of_platform_register_reconfig_notifier(void)
+{
+	WARN_ON(of_reconfig_notifier_register(&platform_of_notifier));
+}
+#endif /* CONFIG_OF_DYNAMIC */
+
+#endif /* CONFIG_OF_ADDRESS */
diff --git a/kernel/drivers/of/resolver.c b/kernel/drivers/of/resolver.c
new file mode 100644
index 000000000..640eb4cb4
--- /dev/null
+++ b/kernel/drivers/of/resolver.c
@@ -0,0 +1,412 @@
+/*
+ * Functions for dealing with DT resolution
+ *
+ * Copyright (C) 2012 Pantelis Antoniou <panto@antoniou-consulting.com>
+ * Copyright (C) 2012 Texas Instruments Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+
+/* illegal phandle value (set when unresolved) */
+#define OF_PHANDLE_ILLEGAL	0xdeadbeef
+
+/**
+ * Find a node with the give full name by recursively following any of
+ * the child node links.
+ */
+static struct device_node *__of_find_node_by_full_name(struct device_node *node,
+		const char *full_name)
+{
+	struct device_node *child, *found;
+
+	if (node == NULL)
+		return NULL;
+
+	/* check */
+	if (of_node_cmp(node->full_name, full_name) == 0)
+		return node;
+
+	for_each_child_of_node(node, child) {
+		found = __of_find_node_by_full_name(child, full_name);
+		if (found != NULL)
+			return found;
+	}
+
+	return NULL;
+}
+
+/*
+ * Find live tree's maximum phandle value.
+ */
+static phandle of_get_tree_max_phandle(void)
+{
+	struct device_node *node;
+	phandle phandle;
+	unsigned long flags;
+
+	/* now search recursively */
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	phandle = 0;
+	for_each_of_allnodes(node) {
+		if (node->phandle != OF_PHANDLE_ILLEGAL &&
+				node->phandle > phandle)
+			phandle = node->phandle;
+	}
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+	return phandle;
+}
+
+/*
+ * Adjust a subtree's phandle values by a given delta.
+ * Makes sure not to just adjust the device node's phandle value,
+ * but modify the phandle properties values as well.
+ */
+static void __of_adjust_tree_phandles(struct device_node *node,
+		int phandle_delta)
+{
+	struct device_node *child;
+	struct property *prop;
+	phandle phandle;
+
+	/* first adjust the node's phandle direct value */
+	if (node->phandle != 0 && node->phandle != OF_PHANDLE_ILLEGAL)
+		node->phandle += phandle_delta;
+
+	/* now adjust phandle & linux,phandle values */
+	for_each_property_of_node(node, prop) {
+
+		/* only look for these two */
+		if (of_prop_cmp(prop->name, "phandle") != 0 &&
+		    of_prop_cmp(prop->name, "linux,phandle") != 0)
+			continue;
+
+		/* must be big enough */
+		if (prop->length < 4)
+			continue;
+
+		/* read phandle value */
+		phandle = be32_to_cpup(prop->value);
+		if (phandle == OF_PHANDLE_ILLEGAL)	/* unresolved */
+			continue;
+
+		/* adjust */
+		*(uint32_t *)prop->value = cpu_to_be32(node->phandle);
+	}
+
+	/* now do the children recursively */
+	for_each_child_of_node(node, child)
+		__of_adjust_tree_phandles(child, phandle_delta);
+}
+
+static int __of_adjust_phandle_ref(struct device_node *node,
+		struct property *rprop, int value)
+{
+	phandle phandle;
+	struct device_node *refnode;
+	struct property *sprop;
+	char *propval, *propcur, *propend, *nodestr, *propstr, *s;
+	int offset, propcurlen;
+	int err = 0;
+
+	/* make a copy */
+	propval = kmalloc(rprop->length, GFP_KERNEL);
+	if (!propval) {
+		pr_err("%s: Could not copy value of '%s'\n",
+				__func__, rprop->name);
+		return -ENOMEM;
+	}
+	memcpy(propval, rprop->value, rprop->length);
+
+	propend = propval + rprop->length;
+	for (propcur = propval; propcur < propend; propcur += propcurlen + 1) {
+		propcurlen = strlen(propcur);
+
+		nodestr = propcur;
+		s = strchr(propcur, ':');
+		if (!s) {
+			pr_err("%s: Illegal symbol entry '%s' (1)\n",
+				__func__, propcur);
+			err = -EINVAL;
+			goto err_fail;
+		}
+		*s++ = '\0';
+
+		propstr = s;
+		s = strchr(s, ':');
+		if (!s) {
+			pr_err("%s: Illegal symbol entry '%s' (2)\n",
+				__func__, (char *)rprop->value);
+			err = -EINVAL;
+			goto err_fail;
+		}
+
+		*s++ = '\0';
+		err = kstrtoint(s, 10, &offset);
+		if (err != 0) {
+			pr_err("%s: Could get offset '%s'\n",
+				__func__, (char *)rprop->value);
+			goto err_fail;
+		}
+
+		/* look into the resolve node for the full path */
+		refnode = __of_find_node_by_full_name(node, nodestr);
+		if (!refnode) {
+			pr_warn("%s: Could not find refnode '%s'\n",
+				__func__, (char *)rprop->value);
+			continue;
+		}
+
+		/* now find the property */
+		for_each_property_of_node(refnode, sprop) {
+			if (of_prop_cmp(sprop->name, propstr) == 0)
+				break;
+		}
+
+		if (!sprop) {
+			pr_err("%s: Could not find property '%s'\n",
+				__func__, (char *)rprop->value);
+			err = -ENOENT;
+			goto err_fail;
+		}
+
+		phandle = value;
+		*(__be32 *)(sprop->value + offset) = cpu_to_be32(phandle);
+	}
+
+err_fail:
+	kfree(propval);
+	return err;
+}
+
+/* compare nodes taking into account that 'name' strips out the @ part */
+static int __of_node_name_cmp(const struct device_node *dn1,
+		const struct device_node *dn2)
+{
+	const char *n1 = strrchr(dn1->full_name, '/') ? : "/";
+	const char *n2 = strrchr(dn2->full_name, '/') ? : "/";
+
+	return of_node_cmp(n1, n2);
+}
+
+/*
+ * Adjust the local phandle references by the given phandle delta.
+ * Assumes the existances of a __local_fixups__ node at the root.
+ * Assumes that __of_verify_tree_phandle_references has been called.
+ * Does not take any devtree locks so make sure you call this on a tree
+ * which is at the detached state.
+ */
+static int __of_adjust_tree_phandle_references(struct device_node *node,
+		struct device_node *target, int phandle_delta)
+{
+	struct device_node *child, *childtarget;
+	struct property *rprop, *sprop;
+	int err, i, count;
+	unsigned int off;
+	phandle phandle;
+
+	if (node == NULL)
+		return 0;
+
+	for_each_property_of_node(node, rprop) {
+
+		/* skip properties added automatically */
+		if (of_prop_cmp(rprop->name, "name") == 0 ||
+		    of_prop_cmp(rprop->name, "phandle") == 0 ||
+		    of_prop_cmp(rprop->name, "linux,phandle") == 0)
+			continue;
+
+		if ((rprop->length % 4) != 0 || rprop->length == 0) {
+			pr_err("%s: Illegal property (size) '%s' @%s\n",
+					__func__, rprop->name, node->full_name);
+			return -EINVAL;
+		}
+		count = rprop->length / sizeof(__be32);
+
+		/* now find the target property */
+		for_each_property_of_node(target, sprop) {
+			if (of_prop_cmp(sprop->name, rprop->name) == 0)
+				break;
+		}
+
+		if (sprop == NULL) {
+			pr_err("%s: Could not find target property '%s' @%s\n",
+					__func__, rprop->name, node->full_name);
+			return -EINVAL;
+		}
+
+		for (i = 0; i < count; i++) {
+			off = be32_to_cpu(((__be32 *)rprop->value)[i]);
+			/* make sure the offset doesn't overstep (even wrap) */
+			if (off >= sprop->length ||
+					(off + 4) > sprop->length) {
+				pr_err("%s: Illegal property '%s' @%s\n",
+						__func__, rprop->name,
+						node->full_name);
+				return -EINVAL;
+			}
+
+			if (phandle_delta) {
+				/* adjust */
+				phandle = be32_to_cpu(*(__be32 *)(sprop->value + off));
+				phandle += phandle_delta;
+				*(__be32 *)(sprop->value + off) = cpu_to_be32(phandle);
+			}
+		}
+	}
+
+	for_each_child_of_node(node, child) {
+
+		for_each_child_of_node(target, childtarget)
+			if (__of_node_name_cmp(child, childtarget) == 0)
+				break;
+
+		if (!childtarget) {
+			pr_err("%s: Could not find target child '%s' @%s\n",
+					__func__, child->name, node->full_name);
+			return -EINVAL;
+		}
+
+		err = __of_adjust_tree_phandle_references(child, childtarget,
+				phandle_delta);
+		if (err != 0)
+			return err;
+	}
+
+	return 0;
+}
+
+/**
+ * of_resolve	- Resolve the given node against the live tree.
+ *
+ * @resolve:	Node to resolve
+ *
+ * Perform dynamic Device Tree resolution against the live tree
+ * to the given node to resolve. This depends on the live tree
+ * having a __symbols__ node, and the resolve node the __fixups__ &
+ * __local_fixups__ nodes (if needed).
+ * The result of the operation is a resolve node that it's contents
+ * are fit to be inserted or operate upon the live tree.
+ * Returns 0 on success or a negative error value on error.
+ */
+int of_resolve_phandles(struct device_node *resolve)
+{
+	struct device_node *child, *childroot, *refnode;
+	struct device_node *root_sym, *resolve_sym, *resolve_fix;
+	struct property *rprop;
+	const char *refpath;
+	phandle phandle, phandle_delta;
+	int err;
+
+	/* the resolve node must exist, and be detached */
+	if (!resolve || !of_node_check_flag(resolve, OF_DETACHED))
+		return -EINVAL;
+
+	/* first we need to adjust the phandles */
+	phandle_delta = of_get_tree_max_phandle() + 1;
+	__of_adjust_tree_phandles(resolve, phandle_delta);
+
+	/* locate the local fixups */
+	childroot = NULL;
+	for_each_child_of_node(resolve, childroot)
+		if (of_node_cmp(childroot->name, "__local_fixups__") == 0)
+			break;
+
+	if (childroot != NULL) {
+		/* resolve root is guaranteed to be the '/' */
+		err = __of_adjust_tree_phandle_references(childroot,
+				resolve, 0);
+		if (err != 0)
+			return err;
+
+		BUG_ON(__of_adjust_tree_phandle_references(childroot,
+				resolve, phandle_delta));
+	}
+
+	root_sym = NULL;
+	resolve_sym = NULL;
+	resolve_fix = NULL;
+
+	/* this may fail (if no fixups are required) */
+	root_sym = of_find_node_by_path("/__symbols__");
+
+	/* locate the symbols & fixups nodes on resolve */
+	for_each_child_of_node(resolve, child) {
+
+		if (!resolve_sym &&
+				of_node_cmp(child->name, "__symbols__") == 0)
+			resolve_sym = child;
+
+		if (!resolve_fix &&
+				of_node_cmp(child->name, "__fixups__") == 0)
+			resolve_fix = child;
+
+		/* both found, don't bother anymore */
+		if (resolve_sym && resolve_fix)
+			break;
+	}
+
+	/* we do allow for the case where no fixups are needed */
+	if (!resolve_fix) {
+		err = 0;	/* no error */
+		goto out;
+	}
+
+	/* we need to fixup, but no root symbols... */
+	if (!root_sym) {
+		err = -EINVAL;
+		goto out;
+	}
+
+	for_each_property_of_node(resolve_fix, rprop) {
+
+		/* skip properties added automatically */
+		if (of_prop_cmp(rprop->name, "name") == 0)
+			continue;
+
+		err = of_property_read_string(root_sym,
+				rprop->name, &refpath);
+		if (err != 0) {
+			pr_err("%s: Could not find symbol '%s'\n",
+					__func__, rprop->name);
+			goto out;
+		}
+
+		refnode = of_find_node_by_path(refpath);
+		if (!refnode) {
+			pr_err("%s: Could not find node by path '%s'\n",
+					__func__, refpath);
+			err = -ENOENT;
+			goto out;
+		}
+
+		phandle = refnode->phandle;
+		of_node_put(refnode);
+
+		pr_debug("%s: %s phandle is 0x%08x\n",
+				__func__, rprop->name, phandle);
+
+		err = __of_adjust_phandle_ref(resolve, rprop, phandle);
+		if (err)
+			break;
+	}
+
+out:
+	/* NULL is handled by of_node_put as NOP */
+	of_node_put(root_sym);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(of_resolve_phandles);
diff --git a/kernel/drivers/of/unittest-data/.gitignore b/kernel/drivers/of/unittest-data/.gitignore
new file mode 100644
index 000000000..4b3cf8b16
--- /dev/null
+++ b/kernel/drivers/of/unittest-data/.gitignore
@@ -0,0 +1,2 @@
+testcases.dtb
+testcases.dtb.S
diff --git a/kernel/drivers/of/unittest-data/Makefile b/kernel/drivers/of/unittest-data/Makefile
new file mode 100644
index 000000000..1ac5cc01d
--- /dev/null
+++ b/kernel/drivers/of/unittest-data/Makefile
@@ -0,0 +1,7 @@
+obj-y += testcases.dtb.o
+
+targets += testcases.dtb testcases.dtb.S
+
+.SECONDARY: \
+	$(obj)/testcases.dtb.S \
+	$(obj)/testcases.dtb
diff --git a/kernel/drivers/of/unittest-data/testcases.dts b/kernel/drivers/of/unittest-data/testcases.dts
new file mode 100644
index 000000000..12f7c3d64
--- /dev/null
+++ b/kernel/drivers/of/unittest-data/testcases.dts
@@ -0,0 +1,79 @@
+/dts-v1/;
+/ {
+	testcase-data {
+		changeset {
+			prop-update = "hello";
+			prop-remove = "world";
+			node-remove {
+			};
+		};
+	};
+};
+#include "tests-phandle.dtsi"
+#include "tests-interrupts.dtsi"
+#include "tests-match.dtsi"
+#include "tests-platform.dtsi"
+#include "tests-overlay.dtsi"
+
+/*
+ * phandle fixup data - generated by dtc patches that aren't upstream.
+ * This data must be regenerated whenever phandle references are modified in
+ * the testdata tree.
+ *
+ * The format of this data may be subject to change. For the time being consider
+ * this a kernel-internal data format.
+ */
+/ { __local_fixups__ {
+	testcase-data {
+		phandle-tests {
+			consumer-a {
+				phandle-list = <0x00000000 0x00000008
+						0x00000018 0x00000028
+						0x00000034 0x00000038>;
+				phandle-list-bad-args = <0x00000000 0x0000000c>;
+			};
+		};
+		interrupts {
+			intmap0 {
+				interrupt-map = <0x00000004 0x00000010
+						 0x00000024 0x00000034>;
+			};
+			intmap1 {
+				interrupt-map = <0x0000000c>;
+			};
+			interrupts0 {
+				interrupt-parent = <0x00000000>;
+			};
+			interrupts1 {
+				interrupt-parent = <0x00000000>;
+			};
+			interrupts-extended0 {
+				interrupts-extended = <0x00000000 0x00000008
+						       0x00000018 0x00000024
+						       0x0000002c 0x00000034
+						       0x0000003c>;
+			};
+		};
+		testcase-device1 {
+			interrupt-parent = <0x00000000>;
+		};
+		testcase-device2 {
+			interrupt-parent = <0x00000000>;
+		};
+		overlay2 {
+			fragment@0 {
+				target = <0x00000000>;
+			};
+		};
+		overlay3 {
+			fragment@0 {
+				target = <0x00000000>;
+			};
+		};
+		overlay4 {
+			fragment@0 {
+				target = <0x00000000>;
+			};
+		};
+	};
+}; };
diff --git a/kernel/drivers/of/unittest-data/tests-interrupts.dtsi b/kernel/drivers/of/unittest-data/tests-interrupts.dtsi
new file mode 100644
index 000000000..da4695f60
--- /dev/null
+++ b/kernel/drivers/of/unittest-data/tests-interrupts.dtsi
@@ -0,0 +1,71 @@
+
+/ {
+	testcase-data {
+		interrupts {
+			#address-cells = <1>;
+			#size-cells = <1>;
+			test_intc0: intc0 {
+				interrupt-controller;
+				#interrupt-cells = <1>;
+			};
+
+			test_intc1: intc1 {
+				interrupt-controller;
+				#interrupt-cells = <3>;
+			};
+
+			test_intc2: intc2 {
+				interrupt-controller;
+				#interrupt-cells = <2>;
+			};
+
+			test_intmap0: intmap0 {
+				#interrupt-cells = <1>;
+				#address-cells = <0>;
+				interrupt-map = <1 &test_intc0 9>,
+						<2 &test_intc1 10 11 12>,
+						<3 &test_intc2 13 14>,
+						<4 &test_intc2 15 16>;
+			};
+
+			test_intmap1: intmap1 {
+				#interrupt-cells = <2>;
+				interrupt-map = <0x5000 1 2 &test_intc0 15>;
+			};
+
+			interrupts0 {
+				interrupt-parent = <&test_intc0>;
+				interrupts = <1>, <2>, <3>, <4>;
+			};
+
+			interrupts1 {
+				interrupt-parent = <&test_intmap0>;
+				interrupts = <1>, <2>, <3>, <4>;
+			};
+
+			interrupts-extended0 {
+				reg = <0x5000 0x100>;
+				interrupts-extended = <&test_intc0 1>,
+						      <&test_intc1 2 3 4>,
+						      <&test_intc2 5 6>,
+						      <&test_intmap0 1>,
+						      <&test_intmap0 2>,
+						      <&test_intmap0 3>,
+						      <&test_intmap1 1 2>;
+			};
+		};
+
+		testcase-device1 {
+			compatible = "testcase-device";
+			interrupt-parent = <&test_intc0>;
+			interrupts = <1>;
+		};
+
+		testcase-device2 {
+			compatible = "testcase-device";
+			interrupt-parent = <&test_intc2>;
+			interrupts = <1>; /* invalid specifier - too short */
+		};
+	};
+
+};
diff --git a/kernel/drivers/of/unittest-data/tests-match.dtsi b/kernel/drivers/of/unittest-data/tests-match.dtsi
new file mode 100644
index 000000000..c9e541129
--- /dev/null
+++ b/kernel/drivers/of/unittest-data/tests-match.dtsi
@@ -0,0 +1,19 @@
+
+/ {
+	testcase-data {
+		match-node {
+			name0 { };
+			name1 { device_type = "type1"; };
+			a { name2 { device_type = "type1"; }; };
+			b { name2 { }; };
+			c { name2 { device_type = "type2"; }; };
+			name3 { compatible = "compat3"; };
+			name4 { compatible = "compat2", "compat3"; };
+			name5 { compatible = "compat2", "compat3"; };
+			name6 { compatible = "compat1", "compat2", "compat3"; };
+			name7 { compatible = "compat2"; device_type = "type1"; };
+			name8 { compatible = "compat2"; device_type = "type1"; };
+			name9 { compatible = "compat2"; };
+		};
+	};
+};
diff --git a/kernel/drivers/of/unittest-data/tests-overlay.dtsi b/kernel/drivers/of/unittest-data/tests-overlay.dtsi
new file mode 100644
index 000000000..02ba56c20
--- /dev/null
+++ b/kernel/drivers/of/unittest-data/tests-overlay.dtsi
@@ -0,0 +1,329 @@
+
+/ {
+	testcase-data {
+		overlay-node {
+
+			/* test bus */
+			unittestbus: test-bus {
+				compatible = "simple-bus";
+				#address-cells = <1>;
+				#size-cells = <0>;
+
+				unittest100: test-unittest100 {
+					compatible = "unittest";
+					status = "okay";
+					reg = <100>;
+				};
+
+				unittest101: test-unittest101 {
+					compatible = "unittest";
+					status = "disabled";
+					reg = <101>;
+				};
+
+				unittest0: test-unittest0 {
+					compatible = "unittest";
+					status = "disabled";
+					reg = <0>;
+				};
+
+				unittest1: test-unittest1 {
+					compatible = "unittest";
+					status = "okay";
+					reg = <1>;
+				};
+
+				unittest2: test-unittest2 {
+					compatible = "unittest";
+					status = "disabled";
+					reg = <2>;
+				};
+
+				unittest3: test-unittest3 {
+					compatible = "unittest";
+					status = "okay";
+					reg = <3>;
+				};
+
+				unittest5: test-unittest5 {
+					compatible = "unittest";
+					status = "disabled";
+					reg = <5>;
+				};
+
+				unittest6: test-unittest6 {
+					compatible = "unittest";
+					status = "disabled";
+					reg = <6>;
+				};
+
+				unittest7: test-unittest7 {
+					compatible = "unittest";
+					status = "disabled";
+					reg = <7>;
+				};
+
+				unittest8: test-unittest8 {
+					compatible = "unittest";
+					status = "disabled";
+					reg = <8>;
+				};
+
+				i2c-test-bus {
+					compatible = "unittest-i2c-bus";
+					status = "okay";
+					reg = <50>;
+
+					#address-cells = <1>;
+					#size-cells = <0>;
+
+					test-unittest12 {
+						reg = <8>;
+						compatible = "unittest-i2c-dev";
+						status = "disabled";
+					};
+
+					test-unittest13 {
+						reg = <9>;
+						compatible = "unittest-i2c-dev";
+						status = "okay";
+					};
+
+					test-unittest14 {
+						reg = <10>;
+						compatible = "unittest-i2c-mux";
+						status = "okay";
+
+						#address-cells = <1>;
+						#size-cells = <0>;
+
+						i2c@0 {
+							#address-cells = <1>;
+							#size-cells = <0>;
+							reg = <0>;
+
+							test-mux-dev {
+								reg = <32>;
+								compatible = "unittest-i2c-dev";
+								status = "okay";
+							};
+						};
+					};
+				};
+			};
+		};
+
+		/* test enable using absolute target path */
+		overlay0 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/test-unittest0";
+				__overlay__ {
+					status = "okay";
+				};
+			};
+		};
+
+		/* test disable using absolute target path */
+		overlay1 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/test-unittest1";
+				__overlay__ {
+					status = "disabled";
+				};
+			};
+		};
+
+		/* test enable using label */
+		overlay2 {
+			fragment@0 {
+				target = <&unittest2>;
+				__overlay__ {
+					status = "okay";
+				};
+			};
+		};
+
+		/* test disable using label */
+		overlay3 {
+			fragment@0 {
+				target = <&unittest3>;
+				__overlay__ {
+					status = "disabled";
+				};
+			};
+		};
+
+		/* test insertion of a full node */
+		overlay4 {
+			fragment@0 {
+				target = <&unittestbus>;
+				__overlay__ {
+
+					/* suppress DTC warning */
+					#address-cells = <1>;
+					#size-cells = <0>;
+
+					test-unittest4 {
+						compatible = "unittest";
+						status = "okay";
+						reg = <4>;
+					};
+				};
+			};
+		};
+
+		/* test overlay apply revert */
+		overlay5 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/test-unittest5";
+				__overlay__ {
+					status = "okay";
+				};
+			};
+		};
+
+		/* test overlays application and removal in sequence */
+		overlay6 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/test-unittest6";
+				__overlay__ {
+					status = "okay";
+				};
+			};
+		};
+		overlay7 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/test-unittest7";
+				__overlay__ {
+					status = "okay";
+				};
+			};
+		};
+
+		/* test overlays application and removal in bad sequence */
+		overlay8 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/test-unittest8";
+				__overlay__ {
+					status = "okay";
+				};
+			};
+		};
+		overlay9 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/test-unittest8";
+				__overlay__ {
+					property-foo = "bar";
+				};
+			};
+		};
+
+		overlay10 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus";
+				__overlay__ {
+
+					/* suppress DTC warning */
+					#address-cells = <1>;
+					#size-cells = <0>;
+
+					test-unittest10 {
+						compatible = "unittest";
+						status = "okay";
+						reg = <10>;
+
+						#address-cells = <1>;
+						#size-cells = <0>;
+
+						test-unittest101 {
+							compatible = "unittest";
+							status = "okay";
+							reg = <1>;
+						};
+
+					};
+				};
+			};
+		};
+
+		overlay11 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus";
+				__overlay__ {
+
+					/* suppress DTC warning */
+					#address-cells = <1>;
+					#size-cells = <0>;
+
+					test-unittest11 {
+						compatible = "unittest";
+						status = "okay";
+						reg = <11>;
+
+						#address-cells = <1>;
+						#size-cells = <0>;
+
+						test-unittest111 {
+							compatible = "unittest";
+							status = "okay";
+							reg = <1>;
+						};
+
+					};
+				};
+			};
+		};
+
+		/* test enable using absolute target path (i2c) */
+		overlay12 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/i2c-test-bus/test-unittest12";
+				__overlay__ {
+					status = "okay";
+				};
+			};
+		};
+
+		/* test disable using absolute target path (i2c) */
+		overlay13 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/i2c-test-bus/test-unittest13";
+				__overlay__ {
+					status = "disabled";
+				};
+			};
+		};
+
+		/* test mux overlay */
+		overlay15 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/i2c-test-bus";
+				__overlay__ {
+					#address-cells = <1>;
+					#size-cells = <0>;
+					test-unittest15 {
+						reg = <11>;
+						compatible = "unittest-i2c-mux";
+						status = "okay";
+
+						#address-cells = <1>;
+						#size-cells = <0>;
+
+						i2c@0 {
+							#address-cells = <1>;
+							#size-cells = <0>;
+							reg = <0>;
+
+							test-mux-dev {
+								reg = <32>;
+								compatible = "unittest-i2c-dev";
+								status = "okay";
+							};
+						};
+					};
+				};
+			};
+		};
+
+	};
+};
diff --git a/kernel/drivers/of/unittest-data/tests-phandle.dtsi b/kernel/drivers/of/unittest-data/tests-phandle.dtsi
new file mode 100644
index 000000000..5b1527e8a
--- /dev/null
+++ b/kernel/drivers/of/unittest-data/tests-phandle.dtsi
@@ -0,0 +1,48 @@
+
+/ {
+	aliases {
+		testcase-alias = &testcase;
+	};
+
+	testcase: testcase-data {
+		security-password = "password";
+		duplicate-name = "duplicate";
+		duplicate-name { };
+		phandle-tests {
+			provider0: provider0 {
+				#phandle-cells = <0>;
+			};
+
+			provider1: provider1 {
+				#phandle-cells = <1>;
+			};
+
+			provider2: provider2 {
+				#phandle-cells = <2>;
+			};
+
+			provider3: provider3 {
+				#phandle-cells = <3>;
+			};
+
+			consumer-a {
+				phandle-list =	<&provider1 1>,
+						<&provider2 2 0>,
+						<0>,
+						<&provider3 4 4 3>,
+						<&provider2 5 100>,
+						<&provider0>,
+						<&provider1 7>;
+				phandle-list-names = "first", "second", "third";
+
+				phandle-list-bad-phandle = <12345678 0 0>;
+				phandle-list-bad-args = <&provider2 1 0>,
+							<&provider3 0>;
+				empty-property;
+				string-property = "foobar";
+				unterminated-string = [40 41 42 43];
+				unterminated-string-list = "first", "second", [40 41 42 43];
+			};
+		};
+	};
+};
diff --git a/kernel/drivers/of/unittest-data/tests-platform.dtsi b/kernel/drivers/of/unittest-data/tests-platform.dtsi
new file mode 100644
index 000000000..eb20eeb2b
--- /dev/null
+++ b/kernel/drivers/of/unittest-data/tests-platform.dtsi
@@ -0,0 +1,35 @@
+
+/ {
+	testcase-data {
+		platform-tests {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			test-device@0 {
+				compatible = "test-device";
+				reg = <0x0>;
+
+				#address-cells = <1>;
+				#size-cells = <0>;
+
+				dev@100 {
+					compatible = "test-sub-device";
+					reg = <0x100>;
+				};
+			};
+
+			test-device@1 {
+				compatible = "test-device";
+				reg = <0x1>;
+
+				#address-cells = <1>;
+				#size-cells = <0>;
+
+				dev@100 {
+					compatible = "test-sub-device";
+					reg = <0x100>;
+				};
+			};
+		};
+	};
+};
diff --git a/kernel/drivers/of/unittest.c b/kernel/drivers/of/unittest.c
new file mode 100644
index 000000000..18016341d
--- /dev/null
+++ b/kernel/drivers/of/unittest.c
@@ -0,0 +1,1970 @@
+/*
+ * Self tests for device tree subsystem
+ */
+
+#define pr_fmt(fmt) "### dt-test ### " fmt
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/hashtable.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/of_platform.h>
+
+#include <linux/i2c.h>
+#include <linux/i2c-mux.h>
+
+#include <linux/bitops.h>
+
+#include "of_private.h"
+
+static struct unittest_results {
+	int passed;
+	int failed;
+} unittest_results;
+
+#define unittest(result, fmt, ...) ({ \
+	bool failed = !(result); \
+	if (failed) { \
+		unittest_results.failed++; \
+		pr_err("FAIL %s():%i " fmt, __func__, __LINE__, ##__VA_ARGS__); \
+	} else { \
+		unittest_results.passed++; \
+		pr_debug("pass %s():%i\n", __func__, __LINE__); \
+	} \
+	failed; \
+})
+
+static void __init of_unittest_find_node_by_name(void)
+{
+	struct device_node *np;
+	const char *options;
+
+	np = of_find_node_by_path("/testcase-data");
+	unittest(np && !strcmp("/testcase-data", np->full_name),
+		"find /testcase-data failed\n");
+	of_node_put(np);
+
+	/* Test if trailing '/' works */
+	np = of_find_node_by_path("/testcase-data/");
+	unittest(!np, "trailing '/' on /testcase-data/ should fail\n");
+
+	np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
+	unittest(np && !strcmp("/testcase-data/phandle-tests/consumer-a", np->full_name),
+		"find /testcase-data/phandle-tests/consumer-a failed\n");
+	of_node_put(np);
+
+	np = of_find_node_by_path("testcase-alias");
+	unittest(np && !strcmp("/testcase-data", np->full_name),
+		"find testcase-alias failed\n");
+	of_node_put(np);
+
+	/* Test if trailing '/' works on aliases */
+	np = of_find_node_by_path("testcase-alias/");
+	unittest(!np, "trailing '/' on testcase-alias/ should fail\n");
+
+	np = of_find_node_by_path("testcase-alias/phandle-tests/consumer-a");
+	unittest(np && !strcmp("/testcase-data/phandle-tests/consumer-a", np->full_name),
+		"find testcase-alias/phandle-tests/consumer-a failed\n");
+	of_node_put(np);
+
+	np = of_find_node_by_path("/testcase-data/missing-path");
+	unittest(!np, "non-existent path returned node %s\n", np->full_name);
+	of_node_put(np);
+
+	np = of_find_node_by_path("missing-alias");
+	unittest(!np, "non-existent alias returned node %s\n", np->full_name);
+	of_node_put(np);
+
+	np = of_find_node_by_path("testcase-alias/missing-path");
+	unittest(!np, "non-existent alias with relative path returned node %s\n", np->full_name);
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("/testcase-data:testoption", &options);
+	unittest(np && !strcmp("testoption", options),
+		 "option path test failed\n");
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("/testcase-data:test/option", &options);
+	unittest(np && !strcmp("test/option", options),
+		 "option path test, subcase #1 failed\n");
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("/testcase-data/testcase-device1:test/option", &options);
+	unittest(np && !strcmp("test/option", options),
+		 "option path test, subcase #2 failed\n");
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("/testcase-data:testoption", NULL);
+	unittest(np, "NULL option path test failed\n");
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("testcase-alias:testaliasoption",
+				       &options);
+	unittest(np && !strcmp("testaliasoption", options),
+		 "option alias path test failed\n");
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("testcase-alias:test/alias/option",
+				       &options);
+	unittest(np && !strcmp("test/alias/option", options),
+		 "option alias path test, subcase #1 failed\n");
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("testcase-alias:testaliasoption", NULL);
+	unittest(np, "NULL option alias path test failed\n");
+	of_node_put(np);
+
+	options = "testoption";
+	np = of_find_node_opts_by_path("testcase-alias", &options);
+	unittest(np && !options, "option clearing test failed\n");
+	of_node_put(np);
+
+	options = "testoption";
+	np = of_find_node_opts_by_path("/", &options);
+	unittest(np && !options, "option clearing root node test failed\n");
+	of_node_put(np);
+}
+
+static void __init of_unittest_dynamic(void)
+{
+	struct device_node *np;
+	struct property *prop;
+
+	np = of_find_node_by_path("/testcase-data");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	/* Array of 4 properties for the purpose of testing */
+	prop = kzalloc(sizeof(*prop) * 4, GFP_KERNEL);
+	if (!prop) {
+		unittest(0, "kzalloc() failed\n");
+		return;
+	}
+
+	/* Add a new property - should pass*/
+	prop->name = "new-property";
+	prop->value = "new-property-data";
+	prop->length = strlen(prop->value);
+	unittest(of_add_property(np, prop) == 0, "Adding a new property failed\n");
+
+	/* Try to add an existing property - should fail */
+	prop++;
+	prop->name = "new-property";
+	prop->value = "new-property-data-should-fail";
+	prop->length = strlen(prop->value);
+	unittest(of_add_property(np, prop) != 0,
+		 "Adding an existing property should have failed\n");
+
+	/* Try to modify an existing property - should pass */
+	prop->value = "modify-property-data-should-pass";
+	prop->length = strlen(prop->value);
+	unittest(of_update_property(np, prop) == 0,
+		 "Updating an existing property should have passed\n");
+
+	/* Try to modify non-existent property - should pass*/
+	prop++;
+	prop->name = "modify-property";
+	prop->value = "modify-missing-property-data-should-pass";
+	prop->length = strlen(prop->value);
+	unittest(of_update_property(np, prop) == 0,
+		 "Updating a missing property should have passed\n");
+
+	/* Remove property - should pass */
+	unittest(of_remove_property(np, prop) == 0,
+		 "Removing a property should have passed\n");
+
+	/* Adding very large property - should pass */
+	prop++;
+	prop->name = "large-property-PAGE_SIZEx8";
+	prop->length = PAGE_SIZE * 8;
+	prop->value = kzalloc(prop->length, GFP_KERNEL);
+	unittest(prop->value != NULL, "Unable to allocate large buffer\n");
+	if (prop->value)
+		unittest(of_add_property(np, prop) == 0,
+			 "Adding a large property should have passed\n");
+}
+
+static int __init of_unittest_check_node_linkage(struct device_node *np)
+{
+	struct device_node *child;
+	int count = 0, rc;
+
+	for_each_child_of_node(np, child) {
+		if (child->parent != np) {
+			pr_err("Child node %s links to wrong parent %s\n",
+				 child->name, np->name);
+			return -EINVAL;
+		}
+
+		rc = of_unittest_check_node_linkage(child);
+		if (rc < 0)
+			return rc;
+		count += rc;
+	}
+
+	return count + 1;
+}
+
+static void __init of_unittest_check_tree_linkage(void)
+{
+	struct device_node *np;
+	int allnode_count = 0, child_count;
+
+	if (!of_root)
+		return;
+
+	for_each_of_allnodes(np)
+		allnode_count++;
+	child_count = of_unittest_check_node_linkage(of_root);
+
+	unittest(child_count > 0, "Device node data structure is corrupted\n");
+	unittest(child_count == allnode_count,
+		 "allnodes list size (%i) doesn't match sibling lists size (%i)\n",
+		 allnode_count, child_count);
+	pr_debug("allnodes list size (%i); sibling lists size (%i)\n", allnode_count, child_count);
+}
+
+struct node_hash {
+	struct hlist_node node;
+	struct device_node *np;
+};
+
+static DEFINE_HASHTABLE(phandle_ht, 8);
+static void __init of_unittest_check_phandles(void)
+{
+	struct device_node *np;
+	struct node_hash *nh;
+	struct hlist_node *tmp;
+	int i, dup_count = 0, phandle_count = 0;
+
+	for_each_of_allnodes(np) {
+		if (!np->phandle)
+			continue;
+
+		hash_for_each_possible(phandle_ht, nh, node, np->phandle) {
+			if (nh->np->phandle == np->phandle) {
+				pr_info("Duplicate phandle! %i used by %s and %s\n",
+					np->phandle, nh->np->full_name, np->full_name);
+				dup_count++;
+				break;
+			}
+		}
+
+		nh = kzalloc(sizeof(*nh), GFP_KERNEL);
+		if (WARN_ON(!nh))
+			return;
+
+		nh->np = np;
+		hash_add(phandle_ht, &nh->node, np->phandle);
+		phandle_count++;
+	}
+	unittest(dup_count == 0, "Found %i duplicates in %i phandles\n",
+		 dup_count, phandle_count);
+
+	/* Clean up */
+	hash_for_each_safe(phandle_ht, i, tmp, nh, node) {
+		hash_del(&nh->node);
+		kfree(nh);
+	}
+}
+
+static void __init of_unittest_parse_phandle_with_args(void)
+{
+	struct device_node *np;
+	struct of_phandle_args args;
+	int i, rc;
+
+	np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	rc = of_count_phandle_with_args(np, "phandle-list", "#phandle-cells");
+	unittest(rc == 7, "of_count_phandle_with_args() returned %i, expected 7\n", rc);
+
+	for (i = 0; i < 8; i++) {
+		bool passed = true;
+
+		rc = of_parse_phandle_with_args(np, "phandle-list",
+						"#phandle-cells", i, &args);
+
+		/* Test the values from tests-phandle.dtsi */
+		switch (i) {
+		case 0:
+			passed &= !rc;
+			passed &= (args.args_count == 1);
+			passed &= (args.args[0] == (i + 1));
+			break;
+		case 1:
+			passed &= !rc;
+			passed &= (args.args_count == 2);
+			passed &= (args.args[0] == (i + 1));
+			passed &= (args.args[1] == 0);
+			break;
+		case 2:
+			passed &= (rc == -ENOENT);
+			break;
+		case 3:
+			passed &= !rc;
+			passed &= (args.args_count == 3);
+			passed &= (args.args[0] == (i + 1));
+			passed &= (args.args[1] == 4);
+			passed &= (args.args[2] == 3);
+			break;
+		case 4:
+			passed &= !rc;
+			passed &= (args.args_count == 2);
+			passed &= (args.args[0] == (i + 1));
+			passed &= (args.args[1] == 100);
+			break;
+		case 5:
+			passed &= !rc;
+			passed &= (args.args_count == 0);
+			break;
+		case 6:
+			passed &= !rc;
+			passed &= (args.args_count == 1);
+			passed &= (args.args[0] == (i + 1));
+			break;
+		case 7:
+			passed &= (rc == -ENOENT);
+			break;
+		default:
+			passed = false;
+		}
+
+		unittest(passed, "index %i - data error on node %s rc=%i\n",
+			 i, args.np->full_name, rc);
+	}
+
+	/* Check for missing list property */
+	rc = of_parse_phandle_with_args(np, "phandle-list-missing",
+					"#phandle-cells", 0, &args);
+	unittest(rc == -ENOENT, "expected:%i got:%i\n", -ENOENT, rc);
+	rc = of_count_phandle_with_args(np, "phandle-list-missing",
+					"#phandle-cells");
+	unittest(rc == -ENOENT, "expected:%i got:%i\n", -ENOENT, rc);
+
+	/* Check for missing cells property */
+	rc = of_parse_phandle_with_args(np, "phandle-list",
+					"#phandle-cells-missing", 0, &args);
+	unittest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc);
+	rc = of_count_phandle_with_args(np, "phandle-list",
+					"#phandle-cells-missing");
+	unittest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc);
+
+	/* Check for bad phandle in list */
+	rc = of_parse_phandle_with_args(np, "phandle-list-bad-phandle",
+					"#phandle-cells", 0, &args);
+	unittest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc);
+	rc = of_count_phandle_with_args(np, "phandle-list-bad-phandle",
+					"#phandle-cells");
+	unittest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc);
+
+	/* Check for incorrectly formed argument list */
+	rc = of_parse_phandle_with_args(np, "phandle-list-bad-args",
+					"#phandle-cells", 1, &args);
+	unittest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc);
+	rc = of_count_phandle_with_args(np, "phandle-list-bad-args",
+					"#phandle-cells");
+	unittest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc);
+}
+
+static void __init of_unittest_property_string(void)
+{
+	const char *strings[4];
+	struct device_node *np;
+	int rc;
+
+	np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
+	if (!np) {
+		pr_err("No testcase data in device tree\n");
+		return;
+	}
+
+	rc = of_property_match_string(np, "phandle-list-names", "first");
+	unittest(rc == 0, "first expected:0 got:%i\n", rc);
+	rc = of_property_match_string(np, "phandle-list-names", "second");
+	unittest(rc == 1, "second expected:1 got:%i\n", rc);
+	rc = of_property_match_string(np, "phandle-list-names", "third");
+	unittest(rc == 2, "third expected:2 got:%i\n", rc);
+	rc = of_property_match_string(np, "phandle-list-names", "fourth");
+	unittest(rc == -ENODATA, "unmatched string; rc=%i\n", rc);
+	rc = of_property_match_string(np, "missing-property", "blah");
+	unittest(rc == -EINVAL, "missing property; rc=%i\n", rc);
+	rc = of_property_match_string(np, "empty-property", "blah");
+	unittest(rc == -ENODATA, "empty property; rc=%i\n", rc);
+	rc = of_property_match_string(np, "unterminated-string", "blah");
+	unittest(rc == -EILSEQ, "unterminated string; rc=%i\n", rc);
+
+	/* of_property_count_strings() tests */
+	rc = of_property_count_strings(np, "string-property");
+	unittest(rc == 1, "Incorrect string count; rc=%i\n", rc);
+	rc = of_property_count_strings(np, "phandle-list-names");
+	unittest(rc == 3, "Incorrect string count; rc=%i\n", rc);
+	rc = of_property_count_strings(np, "unterminated-string");
+	unittest(rc == -EILSEQ, "unterminated string; rc=%i\n", rc);
+	rc = of_property_count_strings(np, "unterminated-string-list");
+	unittest(rc == -EILSEQ, "unterminated string array; rc=%i\n", rc);
+
+	/* of_property_read_string_index() tests */
+	rc = of_property_read_string_index(np, "string-property", 0, strings);
+	unittest(rc == 0 && !strcmp(strings[0], "foobar"), "of_property_read_string_index() failure; rc=%i\n", rc);
+	strings[0] = NULL;
+	rc = of_property_read_string_index(np, "string-property", 1, strings);
+	unittest(rc == -ENODATA && strings[0] == NULL, "of_property_read_string_index() failure; rc=%i\n", rc);
+	rc = of_property_read_string_index(np, "phandle-list-names", 0, strings);
+	unittest(rc == 0 && !strcmp(strings[0], "first"), "of_property_read_string_index() failure; rc=%i\n", rc);
+	rc = of_property_read_string_index(np, "phandle-list-names", 1, strings);
+	unittest(rc == 0 && !strcmp(strings[0], "second"), "of_property_read_string_index() failure; rc=%i\n", rc);
+	rc = of_property_read_string_index(np, "phandle-list-names", 2, strings);
+	unittest(rc == 0 && !strcmp(strings[0], "third"), "of_property_read_string_index() failure; rc=%i\n", rc);
+	strings[0] = NULL;
+	rc = of_property_read_string_index(np, "phandle-list-names", 3, strings);
+	unittest(rc == -ENODATA && strings[0] == NULL, "of_property_read_string_index() failure; rc=%i\n", rc);
+	strings[0] = NULL;
+	rc = of_property_read_string_index(np, "unterminated-string", 0, strings);
+	unittest(rc == -EILSEQ && strings[0] == NULL, "of_property_read_string_index() failure; rc=%i\n", rc);
+	rc = of_property_read_string_index(np, "unterminated-string-list", 0, strings);
+	unittest(rc == 0 && !strcmp(strings[0], "first"), "of_property_read_string_index() failure; rc=%i\n", rc);
+	strings[0] = NULL;
+	rc = of_property_read_string_index(np, "unterminated-string-list", 2, strings); /* should fail */
+	unittest(rc == -EILSEQ && strings[0] == NULL, "of_property_read_string_index() failure; rc=%i\n", rc);
+	strings[1] = NULL;
+
+	/* of_property_read_string_array() tests */
+	rc = of_property_read_string_array(np, "string-property", strings, 4);
+	unittest(rc == 1, "Incorrect string count; rc=%i\n", rc);
+	rc = of_property_read_string_array(np, "phandle-list-names", strings, 4);
+	unittest(rc == 3, "Incorrect string count; rc=%i\n", rc);
+	rc = of_property_read_string_array(np, "unterminated-string", strings, 4);
+	unittest(rc == -EILSEQ, "unterminated string; rc=%i\n", rc);
+	/* -- An incorrectly formed string should cause a failure */
+	rc = of_property_read_string_array(np, "unterminated-string-list", strings, 4);
+	unittest(rc == -EILSEQ, "unterminated string array; rc=%i\n", rc);
+	/* -- parsing the correctly formed strings should still work: */
+	strings[2] = NULL;
+	rc = of_property_read_string_array(np, "unterminated-string-list", strings, 2);
+	unittest(rc == 2 && strings[2] == NULL, "of_property_read_string_array() failure; rc=%i\n", rc);
+	strings[1] = NULL;
+	rc = of_property_read_string_array(np, "phandle-list-names", strings, 1);
+	unittest(rc == 1 && strings[1] == NULL, "Overwrote end of string array; rc=%i, str='%s'\n", rc, strings[1]);
+}
+
+#define propcmp(p1, p2) (((p1)->length == (p2)->length) && \
+			(p1)->value && (p2)->value && \
+			!memcmp((p1)->value, (p2)->value, (p1)->length) && \
+			!strcmp((p1)->name, (p2)->name))
+static void __init of_unittest_property_copy(void)
+{
+#ifdef CONFIG_OF_DYNAMIC
+	struct property p1 = { .name = "p1", .length = 0, .value = "" };
+	struct property p2 = { .name = "p2", .length = 5, .value = "abcd" };
+	struct property *new;
+
+	new = __of_prop_dup(&p1, GFP_KERNEL);
+	unittest(new && propcmp(&p1, new), "empty property didn't copy correctly\n");
+	kfree(new->value);
+	kfree(new->name);
+	kfree(new);
+
+	new = __of_prop_dup(&p2, GFP_KERNEL);
+	unittest(new && propcmp(&p2, new), "non-empty property didn't copy correctly\n");
+	kfree(new->value);
+	kfree(new->name);
+	kfree(new);
+#endif
+}
+
+static void __init of_unittest_changeset(void)
+{
+#ifdef CONFIG_OF_DYNAMIC
+	struct property *ppadd, padd = { .name = "prop-add", .length = 0, .value = "" };
+	struct property *ppupdate, pupdate = { .name = "prop-update", .length = 5, .value = "abcd" };
+	struct property *ppremove;
+	struct device_node *n1, *n2, *n21, *nremove, *parent, *np;
+	struct of_changeset chgset;
+
+	n1 = __of_node_dup(NULL, "/testcase-data/changeset/n1");
+	unittest(n1, "testcase setup failure\n");
+	n2 = __of_node_dup(NULL, "/testcase-data/changeset/n2");
+	unittest(n2, "testcase setup failure\n");
+	n21 = __of_node_dup(NULL, "%s/%s", "/testcase-data/changeset/n2", "n21");
+	unittest(n21, "testcase setup failure %p\n", n21);
+	nremove = of_find_node_by_path("/testcase-data/changeset/node-remove");
+	unittest(nremove, "testcase setup failure\n");
+	ppadd = __of_prop_dup(&padd, GFP_KERNEL);
+	unittest(ppadd, "testcase setup failure\n");
+	ppupdate = __of_prop_dup(&pupdate, GFP_KERNEL);
+	unittest(ppupdate, "testcase setup failure\n");
+	parent = nremove->parent;
+	n1->parent = parent;
+	n2->parent = parent;
+	n21->parent = n2;
+	n2->child = n21;
+	ppremove = of_find_property(parent, "prop-remove", NULL);
+	unittest(ppremove, "failed to find removal prop");
+
+	of_changeset_init(&chgset);
+	unittest(!of_changeset_attach_node(&chgset, n1), "fail attach n1\n");
+	unittest(!of_changeset_attach_node(&chgset, n2), "fail attach n2\n");
+	unittest(!of_changeset_detach_node(&chgset, nremove), "fail remove node\n");
+	unittest(!of_changeset_attach_node(&chgset, n21), "fail attach n21\n");
+	unittest(!of_changeset_add_property(&chgset, parent, ppadd), "fail add prop\n");
+	unittest(!of_changeset_update_property(&chgset, parent, ppupdate), "fail update prop\n");
+	unittest(!of_changeset_remove_property(&chgset, parent, ppremove), "fail remove prop\n");
+	mutex_lock(&of_mutex);
+	unittest(!of_changeset_apply(&chgset), "apply failed\n");
+	mutex_unlock(&of_mutex);
+
+	/* Make sure node names are constructed correctly */
+	unittest((np = of_find_node_by_path("/testcase-data/changeset/n2/n21")),
+		 "'%s' not added\n", n21->full_name);
+	of_node_put(np);
+
+	mutex_lock(&of_mutex);
+	unittest(!of_changeset_revert(&chgset), "revert failed\n");
+	mutex_unlock(&of_mutex);
+
+	of_changeset_destroy(&chgset);
+#endif
+}
+
+static void __init of_unittest_parse_interrupts(void)
+{
+	struct device_node *np;
+	struct of_phandle_args args;
+	int i, rc;
+
+	np = of_find_node_by_path("/testcase-data/interrupts/interrupts0");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	for (i = 0; i < 4; i++) {
+		bool passed = true;
+
+		args.args_count = 0;
+		rc = of_irq_parse_one(np, i, &args);
+
+		passed &= !rc;
+		passed &= (args.args_count == 1);
+		passed &= (args.args[0] == (i + 1));
+
+		unittest(passed, "index %i - data error on node %s rc=%i\n",
+			 i, args.np->full_name, rc);
+	}
+	of_node_put(np);
+
+	np = of_find_node_by_path("/testcase-data/interrupts/interrupts1");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	for (i = 0; i < 4; i++) {
+		bool passed = true;
+
+		args.args_count = 0;
+		rc = of_irq_parse_one(np, i, &args);
+
+		/* Test the values from tests-phandle.dtsi */
+		switch (i) {
+		case 0:
+			passed &= !rc;
+			passed &= (args.args_count == 1);
+			passed &= (args.args[0] == 9);
+			break;
+		case 1:
+			passed &= !rc;
+			passed &= (args.args_count == 3);
+			passed &= (args.args[0] == 10);
+			passed &= (args.args[1] == 11);
+			passed &= (args.args[2] == 12);
+			break;
+		case 2:
+			passed &= !rc;
+			passed &= (args.args_count == 2);
+			passed &= (args.args[0] == 13);
+			passed &= (args.args[1] == 14);
+			break;
+		case 3:
+			passed &= !rc;
+			passed &= (args.args_count == 2);
+			passed &= (args.args[0] == 15);
+			passed &= (args.args[1] == 16);
+			break;
+		default:
+			passed = false;
+		}
+		unittest(passed, "index %i - data error on node %s rc=%i\n",
+			 i, args.np->full_name, rc);
+	}
+	of_node_put(np);
+}
+
+static void __init of_unittest_parse_interrupts_extended(void)
+{
+	struct device_node *np;
+	struct of_phandle_args args;
+	int i, rc;
+
+	np = of_find_node_by_path("/testcase-data/interrupts/interrupts-extended0");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	for (i = 0; i < 7; i++) {
+		bool passed = true;
+
+		rc = of_irq_parse_one(np, i, &args);
+
+		/* Test the values from tests-phandle.dtsi */
+		switch (i) {
+		case 0:
+			passed &= !rc;
+			passed &= (args.args_count == 1);
+			passed &= (args.args[0] == 1);
+			break;
+		case 1:
+			passed &= !rc;
+			passed &= (args.args_count == 3);
+			passed &= (args.args[0] == 2);
+			passed &= (args.args[1] == 3);
+			passed &= (args.args[2] == 4);
+			break;
+		case 2:
+			passed &= !rc;
+			passed &= (args.args_count == 2);
+			passed &= (args.args[0] == 5);
+			passed &= (args.args[1] == 6);
+			break;
+		case 3:
+			passed &= !rc;
+			passed &= (args.args_count == 1);
+			passed &= (args.args[0] == 9);
+			break;
+		case 4:
+			passed &= !rc;
+			passed &= (args.args_count == 3);
+			passed &= (args.args[0] == 10);
+			passed &= (args.args[1] == 11);
+			passed &= (args.args[2] == 12);
+			break;
+		case 5:
+			passed &= !rc;
+			passed &= (args.args_count == 2);
+			passed &= (args.args[0] == 13);
+			passed &= (args.args[1] == 14);
+			break;
+		case 6:
+			passed &= !rc;
+			passed &= (args.args_count == 1);
+			passed &= (args.args[0] == 15);
+			break;
+		default:
+			passed = false;
+		}
+
+		unittest(passed, "index %i - data error on node %s rc=%i\n",
+			 i, args.np->full_name, rc);
+	}
+	of_node_put(np);
+}
+
+static const struct of_device_id match_node_table[] = {
+	{ .data = "A", .name = "name0", }, /* Name alone is lowest priority */
+	{ .data = "B", .type = "type1", }, /* followed by type alone */
+
+	{ .data = "Ca", .name = "name2", .type = "type1", }, /* followed by both together */
+	{ .data = "Cb", .name = "name2", }, /* Only match when type doesn't match */
+	{ .data = "Cc", .name = "name2", .type = "type2", },
+
+	{ .data = "E", .compatible = "compat3" },
+	{ .data = "G", .compatible = "compat2", },
+	{ .data = "H", .compatible = "compat2", .name = "name5", },
+	{ .data = "I", .compatible = "compat2", .type = "type1", },
+	{ .data = "J", .compatible = "compat2", .type = "type1", .name = "name8", },
+	{ .data = "K", .compatible = "compat2", .name = "name9", },
+	{}
+};
+
+static struct {
+	const char *path;
+	const char *data;
+} match_node_tests[] = {
+	{ .path = "/testcase-data/match-node/name0", .data = "A", },
+	{ .path = "/testcase-data/match-node/name1", .data = "B", },
+	{ .path = "/testcase-data/match-node/a/name2", .data = "Ca", },
+	{ .path = "/testcase-data/match-node/b/name2", .data = "Cb", },
+	{ .path = "/testcase-data/match-node/c/name2", .data = "Cc", },
+	{ .path = "/testcase-data/match-node/name3", .data = "E", },
+	{ .path = "/testcase-data/match-node/name4", .data = "G", },
+	{ .path = "/testcase-data/match-node/name5", .data = "H", },
+	{ .path = "/testcase-data/match-node/name6", .data = "G", },
+	{ .path = "/testcase-data/match-node/name7", .data = "I", },
+	{ .path = "/testcase-data/match-node/name8", .data = "J", },
+	{ .path = "/testcase-data/match-node/name9", .data = "K", },
+};
+
+static void __init of_unittest_match_node(void)
+{
+	struct device_node *np;
+	const struct of_device_id *match;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(match_node_tests); i++) {
+		np = of_find_node_by_path(match_node_tests[i].path);
+		if (!np) {
+			unittest(0, "missing testcase node %s\n",
+				match_node_tests[i].path);
+			continue;
+		}
+
+		match = of_match_node(match_node_table, np);
+		if (!match) {
+			unittest(0, "%s didn't match anything\n",
+				match_node_tests[i].path);
+			continue;
+		}
+
+		if (strcmp(match->data, match_node_tests[i].data) != 0) {
+			unittest(0, "%s got wrong match. expected %s, got %s\n",
+				match_node_tests[i].path, match_node_tests[i].data,
+				(const char *)match->data);
+			continue;
+		}
+		unittest(1, "passed");
+	}
+}
+
+static const struct platform_device_info test_bus_info = {
+	.name = "unittest-bus",
+};
+static void __init of_unittest_platform_populate(void)
+{
+	int irq, rc;
+	struct device_node *np, *child, *grandchild;
+	struct platform_device *pdev, *test_bus;
+	const struct of_device_id match[] = {
+		{ .compatible = "test-device", },
+		{}
+	};
+
+	np = of_find_node_by_path("/testcase-data");
+	of_platform_populate(np, of_default_bus_match_table, NULL, NULL);
+
+	/* Test that a missing irq domain returns -EPROBE_DEFER */
+	np = of_find_node_by_path("/testcase-data/testcase-device1");
+	pdev = of_find_device_by_node(np);
+	unittest(pdev, "device 1 creation failed\n");
+
+	irq = platform_get_irq(pdev, 0);
+	unittest(irq == -EPROBE_DEFER, "device deferred probe failed - %d\n", irq);
+
+	/* Test that a parsing failure does not return -EPROBE_DEFER */
+	np = of_find_node_by_path("/testcase-data/testcase-device2");
+	pdev = of_find_device_by_node(np);
+	unittest(pdev, "device 2 creation failed\n");
+	irq = platform_get_irq(pdev, 0);
+	unittest(irq < 0 && irq != -EPROBE_DEFER, "device parsing error failed - %d\n", irq);
+
+	np = of_find_node_by_path("/testcase-data/platform-tests");
+	unittest(np, "No testcase data in device tree\n");
+	if (!np)
+		return;
+
+	test_bus = platform_device_register_full(&test_bus_info);
+	rc = PTR_ERR_OR_ZERO(test_bus);
+	unittest(!rc, "testbus registration failed; rc=%i\n", rc);
+	if (rc)
+		return;
+	test_bus->dev.of_node = np;
+
+	of_platform_populate(np, match, NULL, &test_bus->dev);
+	for_each_child_of_node(np, child) {
+		for_each_child_of_node(child, grandchild)
+			unittest(of_find_device_by_node(grandchild),
+				 "Could not create device for node '%s'\n",
+				 grandchild->name);
+	}
+
+	of_platform_depopulate(&test_bus->dev);
+	for_each_child_of_node(np, child) {
+		for_each_child_of_node(child, grandchild)
+			unittest(!of_find_device_by_node(grandchild),
+				 "device didn't get destroyed '%s'\n",
+				 grandchild->name);
+	}
+
+	platform_device_unregister(test_bus);
+	of_node_put(np);
+}
+
+/**
+ *	update_node_properties - adds the properties
+ *	of np into dup node (present in live tree) and
+ *	updates parent of children of np to dup.
+ *
+ *	@np:	node already present in live tree
+ *	@dup:	node present in live tree to be updated
+ */
+static void update_node_properties(struct device_node *np,
+					struct device_node *dup)
+{
+	struct property *prop;
+	struct device_node *child;
+
+	for_each_property_of_node(np, prop)
+		of_add_property(dup, prop);
+
+	for_each_child_of_node(np, child)
+		child->parent = dup;
+}
+
+/**
+ *	attach_node_and_children - attaches nodes
+ *	and its children to live tree
+ *
+ *	@np:	Node to attach to live tree
+ */
+static int attach_node_and_children(struct device_node *np)
+{
+	struct device_node *next, *dup, *child;
+	unsigned long flags;
+
+	dup = of_find_node_by_path(np->full_name);
+	if (dup) {
+		update_node_properties(np, dup);
+		return 0;
+	}
+
+	child = np->child;
+	np->child = NULL;
+
+	mutex_lock(&of_mutex);
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	np->sibling = np->parent->child;
+	np->parent->child = np;
+	of_node_clear_flag(np, OF_DETACHED);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+	__of_attach_node_sysfs(np);
+	mutex_unlock(&of_mutex);
+
+	while (child) {
+		next = child->sibling;
+		attach_node_and_children(child);
+		child = next;
+	}
+
+	return 0;
+}
+
+/**
+ *	unittest_data_add - Reads, copies data from
+ *	linked tree and attaches it to the live tree
+ */
+static int __init unittest_data_add(void)
+{
+	void *unittest_data;
+	struct device_node *unittest_data_node, *np;
+	/*
+	 * __dtb_testcases_begin[] and __dtb_testcases_end[] are magically
+	 * created by cmd_dt_S_dtb in scripts/Makefile.lib
+	 */
+	extern uint8_t __dtb_testcases_begin[];
+	extern uint8_t __dtb_testcases_end[];
+	const int size = __dtb_testcases_end - __dtb_testcases_begin;
+	int rc;
+
+	if (!size) {
+		pr_warn("%s: No testcase data to attach; not running tests\n",
+			__func__);
+		return -ENODATA;
+	}
+
+	/* creating copy */
+	unittest_data = kmemdup(__dtb_testcases_begin, size, GFP_KERNEL);
+
+	if (!unittest_data) {
+		pr_warn("%s: Failed to allocate memory for unittest_data; "
+			"not running tests\n", __func__);
+		return -ENOMEM;
+	}
+	of_fdt_unflatten_tree(unittest_data, &unittest_data_node);
+	if (!unittest_data_node) {
+		pr_warn("%s: No tree to attach; not running tests\n", __func__);
+		return -ENODATA;
+	}
+	of_node_set_flag(unittest_data_node, OF_DETACHED);
+	rc = of_resolve_phandles(unittest_data_node);
+	if (rc) {
+		pr_err("%s: Failed to resolve phandles (rc=%i)\n", __func__, rc);
+		return -EINVAL;
+	}
+
+	if (!of_root) {
+		of_root = unittest_data_node;
+		for_each_of_allnodes(np)
+			__of_attach_node_sysfs(np);
+		of_aliases = of_find_node_by_path("/aliases");
+		of_chosen = of_find_node_by_path("/chosen");
+		return 0;
+	}
+
+	/* attach the sub-tree to live tree */
+	np = unittest_data_node->child;
+	while (np) {
+		struct device_node *next = np->sibling;
+
+		np->parent = of_root;
+		attach_node_and_children(np);
+		np = next;
+	}
+	return 0;
+}
+
+#ifdef CONFIG_OF_OVERLAY
+
+static int unittest_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+
+	if (np == NULL) {
+		dev_err(dev, "No OF data for device\n");
+		return -EINVAL;
+
+	}
+
+	dev_dbg(dev, "%s for node @%s\n", __func__, np->full_name);
+
+	of_platform_populate(np, NULL, NULL, &pdev->dev);
+
+	return 0;
+}
+
+static int unittest_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+
+	dev_dbg(dev, "%s for node @%s\n", __func__, np->full_name);
+	return 0;
+}
+
+static const struct of_device_id unittest_match[] = {
+	{ .compatible = "unittest", },
+	{},
+};
+
+static struct platform_driver unittest_driver = {
+	.probe			= unittest_probe,
+	.remove			= unittest_remove,
+	.driver = {
+		.name		= "unittest",
+		.owner		= THIS_MODULE,
+		.of_match_table	= of_match_ptr(unittest_match),
+	},
+};
+
+/* get the platform device instantiated at the path */
+static struct platform_device *of_path_to_platform_device(const char *path)
+{
+	struct device_node *np;
+	struct platform_device *pdev;
+
+	np = of_find_node_by_path(path);
+	if (np == NULL)
+		return NULL;
+
+	pdev = of_find_device_by_node(np);
+	of_node_put(np);
+
+	return pdev;
+}
+
+/* find out if a platform device exists at that path */
+static int of_path_platform_device_exists(const char *path)
+{
+	struct platform_device *pdev;
+
+	pdev = of_path_to_platform_device(path);
+	platform_device_put(pdev);
+	return pdev != NULL;
+}
+
+#if IS_BUILTIN(CONFIG_I2C)
+
+/* get the i2c client device instantiated at the path */
+static struct i2c_client *of_path_to_i2c_client(const char *path)
+{
+	struct device_node *np;
+	struct i2c_client *client;
+
+	np = of_find_node_by_path(path);
+	if (np == NULL)
+		return NULL;
+
+	client = of_find_i2c_device_by_node(np);
+	of_node_put(np);
+
+	return client;
+}
+
+/* find out if a i2c client device exists at that path */
+static int of_path_i2c_client_exists(const char *path)
+{
+	struct i2c_client *client;
+
+	client = of_path_to_i2c_client(path);
+	if (client)
+		put_device(&client->dev);
+	return client != NULL;
+}
+#else
+static int of_path_i2c_client_exists(const char *path)
+{
+	return 0;
+}
+#endif
+
+enum overlay_type {
+	PDEV_OVERLAY,
+	I2C_OVERLAY
+};
+
+static int of_path_device_type_exists(const char *path,
+		enum overlay_type ovtype)
+{
+	switch (ovtype) {
+	case PDEV_OVERLAY:
+		return of_path_platform_device_exists(path);
+	case I2C_OVERLAY:
+		return of_path_i2c_client_exists(path);
+	}
+	return 0;
+}
+
+static const char *unittest_path(int nr, enum overlay_type ovtype)
+{
+	const char *base;
+	static char buf[256];
+
+	switch (ovtype) {
+	case PDEV_OVERLAY:
+		base = "/testcase-data/overlay-node/test-bus";
+		break;
+	case I2C_OVERLAY:
+		base = "/testcase-data/overlay-node/test-bus/i2c-test-bus";
+		break;
+	default:
+		buf[0] = '\0';
+		return buf;
+	}
+	snprintf(buf, sizeof(buf) - 1, "%s/test-unittest%d", base, nr);
+	buf[sizeof(buf) - 1] = '\0';
+	return buf;
+}
+
+static int of_unittest_device_exists(int unittest_nr, enum overlay_type ovtype)
+{
+	const char *path;
+
+	path = unittest_path(unittest_nr, ovtype);
+
+	switch (ovtype) {
+	case PDEV_OVERLAY:
+		return of_path_platform_device_exists(path);
+	case I2C_OVERLAY:
+		return of_path_i2c_client_exists(path);
+	}
+	return 0;
+}
+
+static const char *overlay_path(int nr)
+{
+	static char buf[256];
+
+	snprintf(buf, sizeof(buf) - 1,
+		"/testcase-data/overlay%d", nr);
+	buf[sizeof(buf) - 1] = '\0';
+
+	return buf;
+}
+
+static const char *bus_path = "/testcase-data/overlay-node/test-bus";
+
+/* it is guaranteed that overlay ids are assigned in sequence */
+#define MAX_UNITTEST_OVERLAYS	256
+static unsigned long overlay_id_bits[BITS_TO_LONGS(MAX_UNITTEST_OVERLAYS)];
+static int overlay_first_id = -1;
+
+static void of_unittest_track_overlay(int id)
+{
+	if (overlay_first_id < 0)
+		overlay_first_id = id;
+	id -= overlay_first_id;
+
+	/* we shouldn't need that many */
+	BUG_ON(id >= MAX_UNITTEST_OVERLAYS);
+	overlay_id_bits[BIT_WORD(id)] |= BIT_MASK(id);
+}
+
+static void of_unittest_untrack_overlay(int id)
+{
+	if (overlay_first_id < 0)
+		return;
+	id -= overlay_first_id;
+	BUG_ON(id >= MAX_UNITTEST_OVERLAYS);
+	overlay_id_bits[BIT_WORD(id)] &= ~BIT_MASK(id);
+}
+
+static void of_unittest_destroy_tracked_overlays(void)
+{
+	int id, ret, defers;
+
+	if (overlay_first_id < 0)
+		return;
+
+	/* try until no defers */
+	do {
+		defers = 0;
+		/* remove in reverse order */
+		for (id = MAX_UNITTEST_OVERLAYS - 1; id >= 0; id--) {
+			if (!(overlay_id_bits[BIT_WORD(id)] & BIT_MASK(id)))
+				continue;
+
+			ret = of_overlay_destroy(id + overlay_first_id);
+			if (ret != 0) {
+				defers++;
+				pr_warn("%s: overlay destroy failed for #%d\n",
+					__func__, id + overlay_first_id);
+				continue;
+			}
+
+			overlay_id_bits[BIT_WORD(id)] &= ~BIT_MASK(id);
+		}
+	} while (defers > 0);
+}
+
+static int of_unittest_apply_overlay(int unittest_nr, int overlay_nr,
+		int *overlay_id)
+{
+	struct device_node *np = NULL;
+	int ret, id = -1;
+
+	np = of_find_node_by_path(overlay_path(overlay_nr));
+	if (np == NULL) {
+		unittest(0, "could not find overlay node @\"%s\"\n",
+				overlay_path(overlay_nr));
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = of_overlay_create(np);
+	if (ret < 0) {
+		unittest(0, "could not create overlay from \"%s\"\n",
+				overlay_path(overlay_nr));
+		goto out;
+	}
+	id = ret;
+	of_unittest_track_overlay(id);
+
+	ret = 0;
+
+out:
+	of_node_put(np);
+
+	if (overlay_id)
+		*overlay_id = id;
+
+	return ret;
+}
+
+/* apply an overlay while checking before and after states */
+static int of_unittest_apply_overlay_check(int overlay_nr, int unittest_nr,
+		int before, int after, enum overlay_type ovtype)
+{
+	int ret;
+
+	/* unittest device must not be in before state */
+	if (of_unittest_device_exists(unittest_nr, ovtype) != before) {
+		unittest(0, "overlay @\"%s\" with device @\"%s\" %s\n",
+				overlay_path(overlay_nr),
+				unittest_path(unittest_nr, ovtype),
+				!before ? "enabled" : "disabled");
+		return -EINVAL;
+	}
+
+	ret = of_unittest_apply_overlay(overlay_nr, unittest_nr, NULL);
+	if (ret != 0) {
+		/* of_unittest_apply_overlay already called unittest() */
+		return ret;
+	}
+
+	/* unittest device must be to set to after state */
+	if (of_unittest_device_exists(unittest_nr, ovtype) != after) {
+		unittest(0, "overlay @\"%s\" failed to create @\"%s\" %s\n",
+				overlay_path(overlay_nr),
+				unittest_path(unittest_nr, ovtype),
+				!after ? "enabled" : "disabled");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* apply an overlay and then revert it while checking before, after states */
+static int of_unittest_apply_revert_overlay_check(int overlay_nr,
+		int unittest_nr, int before, int after,
+		enum overlay_type ovtype)
+{
+	int ret, ov_id;
+
+	/* unittest device must be in before state */
+	if (of_unittest_device_exists(unittest_nr, ovtype) != before) {
+		unittest(0, "overlay @\"%s\" with device @\"%s\" %s\n",
+				overlay_path(overlay_nr),
+				unittest_path(unittest_nr, ovtype),
+				!before ? "enabled" : "disabled");
+		return -EINVAL;
+	}
+
+	/* apply the overlay */
+	ret = of_unittest_apply_overlay(overlay_nr, unittest_nr, &ov_id);
+	if (ret != 0) {
+		/* of_unittest_apply_overlay already called unittest() */
+		return ret;
+	}
+
+	/* unittest device must be in after state */
+	if (of_unittest_device_exists(unittest_nr, ovtype) != after) {
+		unittest(0, "overlay @\"%s\" failed to create @\"%s\" %s\n",
+				overlay_path(overlay_nr),
+				unittest_path(unittest_nr, ovtype),
+				!after ? "enabled" : "disabled");
+		return -EINVAL;
+	}
+
+	ret = of_overlay_destroy(ov_id);
+	if (ret != 0) {
+		unittest(0, "overlay @\"%s\" failed to be destroyed @\"%s\"\n",
+				overlay_path(overlay_nr),
+				unittest_path(unittest_nr, ovtype));
+		return ret;
+	}
+
+	/* unittest device must be again in before state */
+	if (of_unittest_device_exists(unittest_nr, PDEV_OVERLAY) != before) {
+		unittest(0, "overlay @\"%s\" with device @\"%s\" %s\n",
+				overlay_path(overlay_nr),
+				unittest_path(unittest_nr, ovtype),
+				!before ? "enabled" : "disabled");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* test activation of device */
+static void of_unittest_overlay_0(void)
+{
+	int ret;
+
+	/* device should enable */
+	ret = of_unittest_apply_overlay_check(0, 0, 0, 1, PDEV_OVERLAY);
+	if (ret != 0)
+		return;
+
+	unittest(1, "overlay test %d passed\n", 0);
+}
+
+/* test deactivation of device */
+static void of_unittest_overlay_1(void)
+{
+	int ret;
+
+	/* device should disable */
+	ret = of_unittest_apply_overlay_check(1, 1, 1, 0, PDEV_OVERLAY);
+	if (ret != 0)
+		return;
+
+	unittest(1, "overlay test %d passed\n", 1);
+}
+
+/* test activation of device */
+static void of_unittest_overlay_2(void)
+{
+	int ret;
+
+	/* device should enable */
+	ret = of_unittest_apply_overlay_check(2, 2, 0, 1, PDEV_OVERLAY);
+	if (ret != 0)
+		return;
+
+	unittest(1, "overlay test %d passed\n", 2);
+}
+
+/* test deactivation of device */
+static void of_unittest_overlay_3(void)
+{
+	int ret;
+
+	/* device should disable */
+	ret = of_unittest_apply_overlay_check(3, 3, 1, 0, PDEV_OVERLAY);
+	if (ret != 0)
+		return;
+
+	unittest(1, "overlay test %d passed\n", 3);
+}
+
+/* test activation of a full device node */
+static void of_unittest_overlay_4(void)
+{
+	int ret;
+
+	/* device should disable */
+	ret = of_unittest_apply_overlay_check(4, 4, 0, 1, PDEV_OVERLAY);
+	if (ret != 0)
+		return;
+
+	unittest(1, "overlay test %d passed\n", 4);
+}
+
+/* test overlay apply/revert sequence */
+static void of_unittest_overlay_5(void)
+{
+	int ret;
+
+	/* device should disable */
+	ret = of_unittest_apply_revert_overlay_check(5, 5, 0, 1, PDEV_OVERLAY);
+	if (ret != 0)
+		return;
+
+	unittest(1, "overlay test %d passed\n", 5);
+}
+
+/* test overlay application in sequence */
+static void of_unittest_overlay_6(void)
+{
+	struct device_node *np;
+	int ret, i, ov_id[2];
+	int overlay_nr = 6, unittest_nr = 6;
+	int before = 0, after = 1;
+
+	/* unittest device must be in before state */
+	for (i = 0; i < 2; i++) {
+		if (of_unittest_device_exists(unittest_nr + i, PDEV_OVERLAY)
+				!= before) {
+			unittest(0, "overlay @\"%s\" with device @\"%s\" %s\n",
+					overlay_path(overlay_nr + i),
+					unittest_path(unittest_nr + i,
+						PDEV_OVERLAY),
+					!before ? "enabled" : "disabled");
+			return;
+		}
+	}
+
+	/* apply the overlays */
+	for (i = 0; i < 2; i++) {
+
+		np = of_find_node_by_path(overlay_path(overlay_nr + i));
+		if (np == NULL) {
+			unittest(0, "could not find overlay node @\"%s\"\n",
+					overlay_path(overlay_nr + i));
+			return;
+		}
+
+		ret = of_overlay_create(np);
+		if (ret < 0)  {
+			unittest(0, "could not create overlay from \"%s\"\n",
+					overlay_path(overlay_nr + i));
+			return;
+		}
+		ov_id[i] = ret;
+		of_unittest_track_overlay(ov_id[i]);
+	}
+
+	for (i = 0; i < 2; i++) {
+		/* unittest device must be in after state */
+		if (of_unittest_device_exists(unittest_nr + i, PDEV_OVERLAY)
+				!= after) {
+			unittest(0, "overlay @\"%s\" failed @\"%s\" %s\n",
+					overlay_path(overlay_nr + i),
+					unittest_path(unittest_nr + i,
+						PDEV_OVERLAY),
+					!after ? "enabled" : "disabled");
+			return;
+		}
+	}
+
+	for (i = 1; i >= 0; i--) {
+		ret = of_overlay_destroy(ov_id[i]);
+		if (ret != 0) {
+			unittest(0, "overlay @\"%s\" failed destroy @\"%s\"\n",
+					overlay_path(overlay_nr + i),
+					unittest_path(unittest_nr + i,
+						PDEV_OVERLAY));
+			return;
+		}
+		of_unittest_untrack_overlay(ov_id[i]);
+	}
+
+	for (i = 0; i < 2; i++) {
+		/* unittest device must be again in before state */
+		if (of_unittest_device_exists(unittest_nr + i, PDEV_OVERLAY)
+				!= before) {
+			unittest(0, "overlay @\"%s\" with device @\"%s\" %s\n",
+					overlay_path(overlay_nr + i),
+					unittest_path(unittest_nr + i,
+						PDEV_OVERLAY),
+					!before ? "enabled" : "disabled");
+			return;
+		}
+	}
+
+	unittest(1, "overlay test %d passed\n", 6);
+}
+
+/* test overlay application in sequence */
+static void of_unittest_overlay_8(void)
+{
+	struct device_node *np;
+	int ret, i, ov_id[2];
+	int overlay_nr = 8, unittest_nr = 8;
+
+	/* we don't care about device state in this test */
+
+	/* apply the overlays */
+	for (i = 0; i < 2; i++) {
+
+		np = of_find_node_by_path(overlay_path(overlay_nr + i));
+		if (np == NULL) {
+			unittest(0, "could not find overlay node @\"%s\"\n",
+					overlay_path(overlay_nr + i));
+			return;
+		}
+
+		ret = of_overlay_create(np);
+		if (ret < 0)  {
+			unittest(0, "could not create overlay from \"%s\"\n",
+					overlay_path(overlay_nr + i));
+			return;
+		}
+		ov_id[i] = ret;
+		of_unittest_track_overlay(ov_id[i]);
+	}
+
+	/* now try to remove first overlay (it should fail) */
+	ret = of_overlay_destroy(ov_id[0]);
+	if (ret == 0) {
+		unittest(0, "overlay @\"%s\" was destroyed @\"%s\"\n",
+				overlay_path(overlay_nr + 0),
+				unittest_path(unittest_nr,
+					PDEV_OVERLAY));
+		return;
+	}
+
+	/* removing them in order should work */
+	for (i = 1; i >= 0; i--) {
+		ret = of_overlay_destroy(ov_id[i]);
+		if (ret != 0) {
+			unittest(0, "overlay @\"%s\" not destroyed @\"%s\"\n",
+					overlay_path(overlay_nr + i),
+					unittest_path(unittest_nr,
+						PDEV_OVERLAY));
+			return;
+		}
+		of_unittest_untrack_overlay(ov_id[i]);
+	}
+
+	unittest(1, "overlay test %d passed\n", 8);
+}
+
+/* test insertion of a bus with parent devices */
+static void of_unittest_overlay_10(void)
+{
+	int ret;
+	char *child_path;
+
+	/* device should disable */
+	ret = of_unittest_apply_overlay_check(10, 10, 0, 1, PDEV_OVERLAY);
+	if (unittest(ret == 0,
+			"overlay test %d failed; overlay application\n", 10))
+		return;
+
+	child_path = kasprintf(GFP_KERNEL, "%s/test-unittest101",
+			unittest_path(10, PDEV_OVERLAY));
+	if (unittest(child_path, "overlay test %d failed; kasprintf\n", 10))
+		return;
+
+	ret = of_path_device_type_exists(child_path, PDEV_OVERLAY);
+	kfree(child_path);
+	if (unittest(ret, "overlay test %d failed; no child device\n", 10))
+		return;
+}
+
+/* test insertion of a bus with parent devices (and revert) */
+static void of_unittest_overlay_11(void)
+{
+	int ret;
+
+	/* device should disable */
+	ret = of_unittest_apply_revert_overlay_check(11, 11, 0, 1,
+			PDEV_OVERLAY);
+	if (unittest(ret == 0,
+			"overlay test %d failed; overlay application\n", 11))
+		return;
+}
+
+#if IS_BUILTIN(CONFIG_I2C) && IS_ENABLED(CONFIG_OF_OVERLAY)
+
+struct unittest_i2c_bus_data {
+	struct platform_device	*pdev;
+	struct i2c_adapter	adap;
+};
+
+static int unittest_i2c_master_xfer(struct i2c_adapter *adap,
+		struct i2c_msg *msgs, int num)
+{
+	struct unittest_i2c_bus_data *std = i2c_get_adapdata(adap);
+
+	(void)std;
+
+	return num;
+}
+
+static u32 unittest_i2c_functionality(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm unittest_i2c_algo = {
+	.master_xfer	= unittest_i2c_master_xfer,
+	.functionality	= unittest_i2c_functionality,
+};
+
+static int unittest_i2c_bus_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct unittest_i2c_bus_data *std;
+	struct i2c_adapter *adap;
+	int ret;
+
+	if (np == NULL) {
+		dev_err(dev, "No OF data for device\n");
+		return -EINVAL;
+
+	}
+
+	dev_dbg(dev, "%s for node @%s\n", __func__, np->full_name);
+
+	std = devm_kzalloc(dev, sizeof(*std), GFP_KERNEL);
+	if (!std) {
+		dev_err(dev, "Failed to allocate unittest i2c data\n");
+		return -ENOMEM;
+	}
+
+	/* link them together */
+	std->pdev = pdev;
+	platform_set_drvdata(pdev, std);
+
+	adap = &std->adap;
+	i2c_set_adapdata(adap, std);
+	adap->nr = -1;
+	strlcpy(adap->name, pdev->name, sizeof(adap->name));
+	adap->class = I2C_CLASS_DEPRECATED;
+	adap->algo = &unittest_i2c_algo;
+	adap->dev.parent = dev;
+	adap->dev.of_node = dev->of_node;
+	adap->timeout = 5 * HZ;
+	adap->retries = 3;
+
+	ret = i2c_add_numbered_adapter(adap);
+	if (ret != 0) {
+		dev_err(dev, "Failed to add I2C adapter\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int unittest_i2c_bus_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct unittest_i2c_bus_data *std = platform_get_drvdata(pdev);
+
+	dev_dbg(dev, "%s for node @%s\n", __func__, np->full_name);
+	i2c_del_adapter(&std->adap);
+
+	return 0;
+}
+
+static const struct of_device_id unittest_i2c_bus_match[] = {
+	{ .compatible = "unittest-i2c-bus", },
+	{},
+};
+
+static struct platform_driver unittest_i2c_bus_driver = {
+	.probe			= unittest_i2c_bus_probe,
+	.remove			= unittest_i2c_bus_remove,
+	.driver = {
+		.name		= "unittest-i2c-bus",
+		.of_match_table	= of_match_ptr(unittest_i2c_bus_match),
+	},
+};
+
+static int unittest_i2c_dev_probe(struct i2c_client *client,
+		const struct i2c_device_id *id)
+{
+	struct device *dev = &client->dev;
+	struct device_node *np = client->dev.of_node;
+
+	if (!np) {
+		dev_err(dev, "No OF node\n");
+		return -EINVAL;
+	}
+
+	dev_dbg(dev, "%s for node @%s\n", __func__, np->full_name);
+
+	return 0;
+};
+
+static int unittest_i2c_dev_remove(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct device_node *np = client->dev.of_node;
+
+	dev_dbg(dev, "%s for node @%s\n", __func__, np->full_name);
+	return 0;
+}
+
+static const struct i2c_device_id unittest_i2c_dev_id[] = {
+	{ .name = "unittest-i2c-dev" },
+	{ }
+};
+
+static struct i2c_driver unittest_i2c_dev_driver = {
+	.driver = {
+		.name = "unittest-i2c-dev",
+		.owner = THIS_MODULE,
+	},
+	.probe = unittest_i2c_dev_probe,
+	.remove = unittest_i2c_dev_remove,
+	.id_table = unittest_i2c_dev_id,
+};
+
+#if IS_BUILTIN(CONFIG_I2C_MUX)
+
+struct unittest_i2c_mux_data {
+	int nchans;
+	struct i2c_adapter *adap[];
+};
+
+static int unittest_i2c_mux_select_chan(struct i2c_adapter *adap,
+			       void *client, u32 chan)
+{
+	return 0;
+}
+
+static int unittest_i2c_mux_probe(struct i2c_client *client,
+		const struct i2c_device_id *id)
+{
+	int ret, i, nchans, size;
+	struct device *dev = &client->dev;
+	struct i2c_adapter *adap = to_i2c_adapter(dev->parent);
+	struct device_node *np = client->dev.of_node, *child;
+	struct unittest_i2c_mux_data *stm;
+	u32 reg, max_reg;
+
+	dev_dbg(dev, "%s for node @%s\n", __func__, np->full_name);
+
+	if (!np) {
+		dev_err(dev, "No OF node\n");
+		return -EINVAL;
+	}
+
+	max_reg = (u32)-1;
+	for_each_child_of_node(np, child) {
+		ret = of_property_read_u32(child, "reg", &reg);
+		if (ret)
+			continue;
+		if (max_reg == (u32)-1 || reg > max_reg)
+			max_reg = reg;
+	}
+	nchans = max_reg == (u32)-1 ? 0 : max_reg + 1;
+	if (nchans == 0) {
+		dev_err(dev, "No channels\n");
+		return -EINVAL;
+	}
+
+	size = offsetof(struct unittest_i2c_mux_data, adap[nchans]);
+	stm = devm_kzalloc(dev, size, GFP_KERNEL);
+	if (!stm) {
+		dev_err(dev, "Out of memory\n");
+		return -ENOMEM;
+	}
+	stm->nchans = nchans;
+	for (i = 0; i < nchans; i++) {
+		stm->adap[i] = i2c_add_mux_adapter(adap, dev, client,
+				0, i, 0, unittest_i2c_mux_select_chan, NULL);
+		if (!stm->adap[i]) {
+			dev_err(dev, "Failed to register mux #%d\n", i);
+			for (i--; i >= 0; i--)
+				i2c_del_mux_adapter(stm->adap[i]);
+			return -ENODEV;
+		}
+	}
+
+	i2c_set_clientdata(client, stm);
+
+	return 0;
+};
+
+static int unittest_i2c_mux_remove(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct device_node *np = client->dev.of_node;
+	struct unittest_i2c_mux_data *stm = i2c_get_clientdata(client);
+	int i;
+
+	dev_dbg(dev, "%s for node @%s\n", __func__, np->full_name);
+	for (i = stm->nchans - 1; i >= 0; i--)
+		i2c_del_mux_adapter(stm->adap[i]);
+	return 0;
+}
+
+static const struct i2c_device_id unittest_i2c_mux_id[] = {
+	{ .name = "unittest-i2c-mux" },
+	{ }
+};
+
+static struct i2c_driver unittest_i2c_mux_driver = {
+	.driver = {
+		.name = "unittest-i2c-mux",
+		.owner = THIS_MODULE,
+	},
+	.probe = unittest_i2c_mux_probe,
+	.remove = unittest_i2c_mux_remove,
+	.id_table = unittest_i2c_mux_id,
+};
+
+#endif
+
+static int of_unittest_overlay_i2c_init(void)
+{
+	int ret;
+
+	ret = i2c_add_driver(&unittest_i2c_dev_driver);
+	if (unittest(ret == 0,
+			"could not register unittest i2c device driver\n"))
+		return ret;
+
+	ret = platform_driver_register(&unittest_i2c_bus_driver);
+	if (unittest(ret == 0,
+			"could not register unittest i2c bus driver\n"))
+		return ret;
+
+#if IS_BUILTIN(CONFIG_I2C_MUX)
+	ret = i2c_add_driver(&unittest_i2c_mux_driver);
+	if (unittest(ret == 0,
+			"could not register unittest i2c mux driver\n"))
+		return ret;
+#endif
+
+	return 0;
+}
+
+static void of_unittest_overlay_i2c_cleanup(void)
+{
+#if IS_BUILTIN(CONFIG_I2C_MUX)
+	i2c_del_driver(&unittest_i2c_mux_driver);
+#endif
+	platform_driver_unregister(&unittest_i2c_bus_driver);
+	i2c_del_driver(&unittest_i2c_dev_driver);
+}
+
+static void of_unittest_overlay_i2c_12(void)
+{
+	int ret;
+
+	/* device should enable */
+	ret = of_unittest_apply_overlay_check(12, 12, 0, 1, I2C_OVERLAY);
+	if (ret != 0)
+		return;
+
+	unittest(1, "overlay test %d passed\n", 12);
+}
+
+/* test deactivation of device */
+static void of_unittest_overlay_i2c_13(void)
+{
+	int ret;
+
+	/* device should disable */
+	ret = of_unittest_apply_overlay_check(13, 13, 1, 0, I2C_OVERLAY);
+	if (ret != 0)
+		return;
+
+	unittest(1, "overlay test %d passed\n", 13);
+}
+
+/* just check for i2c mux existence */
+static void of_unittest_overlay_i2c_14(void)
+{
+}
+
+static void of_unittest_overlay_i2c_15(void)
+{
+	int ret;
+
+	/* device should enable */
+	ret = of_unittest_apply_overlay_check(16, 15, 0, 1, I2C_OVERLAY);
+	if (ret != 0)
+		return;
+
+	unittest(1, "overlay test %d passed\n", 15);
+}
+
+#else
+
+static inline void of_unittest_overlay_i2c_14(void) { }
+static inline void of_unittest_overlay_i2c_15(void) { }
+
+#endif
+
+static void __init of_unittest_overlay(void)
+{
+	struct device_node *bus_np = NULL;
+	int ret;
+
+	ret = platform_driver_register(&unittest_driver);
+	if (ret != 0) {
+		unittest(0, "could not register unittest driver\n");
+		goto out;
+	}
+
+	bus_np = of_find_node_by_path(bus_path);
+	if (bus_np == NULL) {
+		unittest(0, "could not find bus_path \"%s\"\n", bus_path);
+		goto out;
+	}
+
+	ret = of_platform_populate(bus_np, of_default_bus_match_table,
+			NULL, NULL);
+	if (ret != 0) {
+		unittest(0, "could not populate bus @ \"%s\"\n", bus_path);
+		goto out;
+	}
+
+	if (!of_unittest_device_exists(100, PDEV_OVERLAY)) {
+		unittest(0, "could not find unittest0 @ \"%s\"\n",
+				unittest_path(100, PDEV_OVERLAY));
+		goto out;
+	}
+
+	if (of_unittest_device_exists(101, PDEV_OVERLAY)) {
+		unittest(0, "unittest1 @ \"%s\" should not exist\n",
+				unittest_path(101, PDEV_OVERLAY));
+		goto out;
+	}
+
+	unittest(1, "basic infrastructure of overlays passed");
+
+	/* tests in sequence */
+	of_unittest_overlay_0();
+	of_unittest_overlay_1();
+	of_unittest_overlay_2();
+	of_unittest_overlay_3();
+	of_unittest_overlay_4();
+	of_unittest_overlay_5();
+	of_unittest_overlay_6();
+	of_unittest_overlay_8();
+
+	of_unittest_overlay_10();
+	of_unittest_overlay_11();
+
+#if IS_BUILTIN(CONFIG_I2C)
+	if (unittest(of_unittest_overlay_i2c_init() == 0, "i2c init failed\n"))
+		goto out;
+
+	of_unittest_overlay_i2c_12();
+	of_unittest_overlay_i2c_13();
+	of_unittest_overlay_i2c_14();
+	of_unittest_overlay_i2c_15();
+
+	of_unittest_overlay_i2c_cleanup();
+#endif
+
+	of_unittest_destroy_tracked_overlays();
+
+out:
+	of_node_put(bus_np);
+}
+
+#else
+static inline void __init of_unittest_overlay(void) { }
+#endif
+
+static int __init of_unittest(void)
+{
+	struct device_node *np;
+	int res;
+
+	/* adding data for unittest */
+	res = unittest_data_add();
+	if (res)
+		return res;
+	if (!of_aliases)
+		of_aliases = of_find_node_by_path("/aliases");
+
+	np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
+	if (!np) {
+		pr_info("No testcase data in device tree; not running tests\n");
+		return 0;
+	}
+	of_node_put(np);
+
+	pr_info("start of unittest - you will see error messages\n");
+	of_unittest_check_tree_linkage();
+	of_unittest_check_phandles();
+	of_unittest_find_node_by_name();
+	of_unittest_dynamic();
+	of_unittest_parse_phandle_with_args();
+	of_unittest_property_string();
+	of_unittest_property_copy();
+	of_unittest_changeset();
+	of_unittest_parse_interrupts();
+	of_unittest_parse_interrupts_extended();
+	of_unittest_match_node();
+	of_unittest_platform_populate();
+	of_unittest_overlay();
+
+	/* Double check linkage after removing testcase data */
+	of_unittest_check_tree_linkage();
+
+	pr_info("end of unittest - %i passed, %i failed\n",
+		unittest_results.passed, unittest_results.failed);
+
+	return 0;
+}
+late_initcall(of_unittest);