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Diffstat (limited to 'kernel/arch/arm/mach-davinci/cp_intc.c')
-rw-r--r--kernel/arch/arm/mach-davinci/cp_intc.c222
1 files changed, 222 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-davinci/cp_intc.c b/kernel/arch/arm/mach-davinci/cp_intc.c
new file mode 100644
index 000000000..006dae8df
--- /dev/null
+++ b/kernel/arch/arm/mach-davinci/cp_intc.c
@@ -0,0 +1,222 @@
+/*
+ * TI Common Platform Interrupt Controller (cp_intc) driver
+ *
+ * Author: Steve Chen <schen@mvista.com>
+ * Copyright (C) 2008-2009, MontaVista Software, Inc. <source@mvista.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#include <mach/common.h>
+#include <mach/cp_intc.h>
+
+static inline unsigned int cp_intc_read(unsigned offset)
+{
+ return __raw_readl(davinci_intc_base + offset);
+}
+
+static inline void cp_intc_write(unsigned long value, unsigned offset)
+{
+ __raw_writel(value, davinci_intc_base + offset);
+}
+
+static void cp_intc_ack_irq(struct irq_data *d)
+{
+ cp_intc_write(d->hwirq, CP_INTC_SYS_STAT_IDX_CLR);
+}
+
+/* Disable interrupt */
+static void cp_intc_mask_irq(struct irq_data *d)
+{
+ /* XXX don't know why we need to disable nIRQ here... */
+ cp_intc_write(1, CP_INTC_HOST_ENABLE_IDX_CLR);
+ cp_intc_write(d->hwirq, CP_INTC_SYS_ENABLE_IDX_CLR);
+ cp_intc_write(1, CP_INTC_HOST_ENABLE_IDX_SET);
+}
+
+/* Enable interrupt */
+static void cp_intc_unmask_irq(struct irq_data *d)
+{
+ cp_intc_write(d->hwirq, CP_INTC_SYS_ENABLE_IDX_SET);
+}
+
+static int cp_intc_set_irq_type(struct irq_data *d, unsigned int flow_type)
+{
+ unsigned reg = BIT_WORD(d->hwirq);
+ unsigned mask = BIT_MASK(d->hwirq);
+ unsigned polarity = cp_intc_read(CP_INTC_SYS_POLARITY(reg));
+ unsigned type = cp_intc_read(CP_INTC_SYS_TYPE(reg));
+
+ switch (flow_type) {
+ case IRQ_TYPE_EDGE_RISING:
+ polarity |= mask;
+ type |= mask;
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ polarity &= ~mask;
+ type |= mask;
+ break;
+ case IRQ_TYPE_LEVEL_HIGH:
+ polarity |= mask;
+ type &= ~mask;
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ polarity &= ~mask;
+ type &= ~mask;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ cp_intc_write(polarity, CP_INTC_SYS_POLARITY(reg));
+ cp_intc_write(type, CP_INTC_SYS_TYPE(reg));
+
+ return 0;
+}
+
+/*
+ * Faking this allows us to to work with suspend functions of
+ * generic drivers which call {enable|disable}_irq_wake for
+ * wake up interrupt sources (eg RTC on DA850).
+ */
+static int cp_intc_set_wake(struct irq_data *d, unsigned int on)
+{
+ return 0;
+}
+
+static struct irq_chip cp_intc_irq_chip = {
+ .name = "cp_intc",
+ .irq_ack = cp_intc_ack_irq,
+ .irq_mask = cp_intc_mask_irq,
+ .irq_unmask = cp_intc_unmask_irq,
+ .irq_set_type = cp_intc_set_irq_type,
+ .irq_set_wake = cp_intc_set_wake,
+};
+
+static struct irq_domain *cp_intc_domain;
+
+static int cp_intc_host_map(struct irq_domain *h, unsigned int virq,
+ irq_hw_number_t hw)
+{
+ pr_debug("cp_intc_host_map(%d, 0x%lx)\n", virq, hw);
+
+ irq_set_chip(virq, &cp_intc_irq_chip);
+ set_irq_flags(virq, IRQF_VALID | IRQF_PROBE);
+ irq_set_handler(virq, handle_edge_irq);
+ return 0;
+}
+
+static const struct irq_domain_ops cp_intc_host_ops = {
+ .map = cp_intc_host_map,
+ .xlate = irq_domain_xlate_onetwocell,
+};
+
+int __init cp_intc_of_init(struct device_node *node, struct device_node *parent)
+{
+ u32 num_irq = davinci_soc_info.intc_irq_num;
+ u8 *irq_prio = davinci_soc_info.intc_irq_prios;
+ u32 *host_map = davinci_soc_info.intc_host_map;
+ unsigned num_reg = BITS_TO_LONGS(num_irq);
+ int i, irq_base;
+
+ davinci_intc_type = DAVINCI_INTC_TYPE_CP_INTC;
+ if (node) {
+ davinci_intc_base = of_iomap(node, 0);
+ if (of_property_read_u32(node, "ti,intc-size", &num_irq))
+ pr_warn("unable to get intc-size, default to %d\n",
+ num_irq);
+ } else {
+ davinci_intc_base = ioremap(davinci_soc_info.intc_base, SZ_8K);
+ }
+ if (WARN_ON(!davinci_intc_base))
+ return -EINVAL;
+
+ cp_intc_write(0, CP_INTC_GLOBAL_ENABLE);
+
+ /* Disable all host interrupts */
+ cp_intc_write(0, CP_INTC_HOST_ENABLE(0));
+
+ /* Disable system interrupts */
+ for (i = 0; i < num_reg; i++)
+ cp_intc_write(~0, CP_INTC_SYS_ENABLE_CLR(i));
+
+ /* Set to normal mode, no nesting, no priority hold */
+ cp_intc_write(0, CP_INTC_CTRL);
+ cp_intc_write(0, CP_INTC_HOST_CTRL);
+
+ /* Clear system interrupt status */
+ for (i = 0; i < num_reg; i++)
+ cp_intc_write(~0, CP_INTC_SYS_STAT_CLR(i));
+
+ /* Enable nIRQ (what about nFIQ?) */
+ cp_intc_write(1, CP_INTC_HOST_ENABLE_IDX_SET);
+
+ /*
+ * Priority is determined by host channel: lower channel number has
+ * higher priority i.e. channel 0 has highest priority and channel 31
+ * had the lowest priority.
+ */
+ num_reg = (num_irq + 3) >> 2; /* 4 channels per register */
+ if (irq_prio) {
+ unsigned j, k;
+ u32 val;
+
+ for (k = i = 0; i < num_reg; i++) {
+ for (val = j = 0; j < 4; j++, k++) {
+ val >>= 8;
+ if (k < num_irq)
+ val |= irq_prio[k] << 24;
+ }
+
+ cp_intc_write(val, CP_INTC_CHAN_MAP(i));
+ }
+ } else {
+ /*
+ * Default everything to channel 15 if priority not specified.
+ * Note that channel 0-1 are mapped to nFIQ and channels 2-31
+ * are mapped to nIRQ.
+ */
+ for (i = 0; i < num_reg; i++)
+ cp_intc_write(0x0f0f0f0f, CP_INTC_CHAN_MAP(i));
+ }
+
+ if (host_map)
+ for (i = 0; host_map[i] != -1; i++)
+ cp_intc_write(host_map[i], CP_INTC_HOST_MAP(i));
+
+ irq_base = irq_alloc_descs(-1, 0, num_irq, 0);
+ if (irq_base < 0) {
+ pr_warn("Couldn't allocate IRQ numbers\n");
+ irq_base = 0;
+ }
+
+ /* create a legacy host */
+ cp_intc_domain = irq_domain_add_legacy(node, num_irq,
+ irq_base, 0, &cp_intc_host_ops, NULL);
+
+ if (!cp_intc_domain) {
+ pr_err("cp_intc: failed to allocate irq host!\n");
+ return -EINVAL;
+ }
+
+ /* Enable global interrupt */
+ cp_intc_write(1, CP_INTC_GLOBAL_ENABLE);
+
+ return 0;
+}
+
+void __init cp_intc_init(void)
+{
+ cp_intc_of_init(NULL, NULL);
+}