davinci: INTC: add support for TI cp_intc
Add support for Texas Instuments Common Platform Interrupt Controller
(cp_intc) used on DA830/OMAP-L137.
Signed-off-by: Steve Chen <schen@mvista.com>
Signed-off-by: Mark Greer <mgreer@mvista.com>
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
diff --git a/arch/arm/mach-davinci/cp_intc.c b/arch/arm/mach-davinci/cp_intc.c
new file mode 100644
index 0000000..96c8e97
--- /dev/null
+++ b/arch/arm/mach-davinci/cp_intc.c
@@ -0,0 +1,161 @@
+/*
+ * 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/init.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+
+#include <mach/cp_intc.h>
+
+static void __iomem *cp_intc_base;
+
+static inline unsigned int cp_intc_read(unsigned offset)
+{
+ return __raw_readl(cp_intc_base + offset);
+}
+
+static inline void cp_intc_write(unsigned long value, unsigned offset)
+{
+ __raw_writel(value, cp_intc_base + offset);
+}
+
+static void cp_intc_ack_irq(unsigned int irq)
+{
+ cp_intc_write(irq, CP_INTC_SYS_STAT_IDX_CLR);
+}
+
+/* Disable interrupt */
+static void cp_intc_mask_irq(unsigned int irq)
+{
+ /* XXX don't know why we need to disable nIRQ here... */
+ cp_intc_write(1, CP_INTC_HOST_ENABLE_IDX_CLR);
+ cp_intc_write(irq, CP_INTC_SYS_ENABLE_IDX_CLR);
+ cp_intc_write(1, CP_INTC_HOST_ENABLE_IDX_SET);
+}
+
+/* Enable interrupt */
+static void cp_intc_unmask_irq(unsigned int irq)
+{
+ cp_intc_write(irq, CP_INTC_SYS_ENABLE_IDX_SET);
+}
+
+static int cp_intc_set_irq_type(unsigned int irq, unsigned int flow_type)
+{
+ unsigned reg = BIT_WORD(irq);
+ unsigned mask = BIT_MASK(irq);
+ 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;
+}
+
+static struct irq_chip cp_intc_irq_chip = {
+ .name = "cp_intc",
+ .ack = cp_intc_ack_irq,
+ .mask = cp_intc_mask_irq,
+ .unmask = cp_intc_unmask_irq,
+ .set_type = cp_intc_set_irq_type,
+};
+
+void __init cp_intc_init(void __iomem *base, unsigned short num_irq,
+ u8 *irq_prio)
+{
+ unsigned num_reg = BITS_TO_LONGS(num_irq);
+ int i;
+
+ cp_intc_base = base;
+
+ 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));
+ }
+
+ /* Set up genirq dispatching for cp_intc */
+ for (i = 0; i < num_irq; i++) {
+ set_irq_chip(i, &cp_intc_irq_chip);
+ set_irq_flags(i, IRQF_VALID | IRQF_PROBE);
+ set_irq_handler(i, handle_edge_irq);
+ }
+
+ /* Enable global interrupt */
+ cp_intc_write(1, CP_INTC_GLOBAL_ENABLE);
+}