1 files changed, 82 insertions, 0 deletions
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);