[ARM] Orion: IRQ support

Signed-off-by: Tzachi Perelstein <tzachi@marvell.com>
Reviewed-by: Nicolas Pitre <nico@marvell.com>
Reviewed-by: Lennert Buytenhek <buytenh@marvell.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>

3 files changed, 162 insertions, 1 deletions

diff --git a/arch/arm/mach-orion/Makefile b/arch/arm/mach-orion/Makefile
index d6a6c86faafc..57d459a2090e 100644
--- a/arch/arm/mach-orion/Makefile
+++ b/arch/arm/mach-orion/Makefile
@@ -1 +1 @@
-obj-y  += common.o addr-map.o pci.o gpio.o
+obj-y  += common.o addr-map.o pci.o gpio.o irq.o
diff --git a/arch/arm/mach-orion/common.h b/arch/arm/mach-orion/common.h
index a6a7af189b0e..155371e1d672 100644
--- a/arch/arm/mach-orion/common.h
+++ b/arch/arm/mach-orion/common.h
@@ -6,6 +6,7 @@
  */
 
 void __init orion_map_io(void);
+void __init orion_init_irq(void);
 void __init orion_init(void);
 
 /*
diff --git a/arch/arm/mach-orion/irq.c b/arch/arm/mach-orion/irq.c
new file mode 100644
index 000000000000..585a0fb06262
--- /dev/null
+++ b/arch/arm/mach-orion/irq.c
@@ -0,0 +1,160 @@
+/*
+ * arch/arm/mach-orion/irq.c
+ *
+ * Core IRQ functions for Marvell Orion System On Chip
+ *
+ * Maintainer: Tzachi Perelstein <tzachi@marvell.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/kernel.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <asm/gpio.h>
+#include <asm/arch/orion.h>
+#include "common.h"
+
+/*****************************************************************************
+ * Orion GPIO IRQ
+ ****************************************************************************/
+static void orion_gpio_irq_mask(u32 irq)
+{
+        int pin = irq_to_gpio(irq);
+        orion_clrbits(GPIO_LEVEL_MASK, 1 << pin);
+}
+
+static void orion_gpio_irq_unmask(u32 irq)
+{
+        int pin = irq_to_gpio(irq);
+        orion_setbits(GPIO_LEVEL_MASK, 1 << pin);
+}
+
+static int orion_gpio_set_irq_type(u32 irq, u32 type)
+{
+        int pin = irq_to_gpio(irq);
+
+        if ((orion_read(GPIO_IO_CONF) & (1 << pin)) == 0) {
+                printk(KERN_ERR "orion_gpio_set_irq_type failed "
+                                "(irq %d, pin %d).\n", irq, pin);
+                return -EINVAL;
+        }
+
+        switch (type) {
+        case IRQT_HIGH:
+                orion_clrbits(GPIO_IN_POL, (1 << pin));
+                break;
+        case IRQT_LOW:
+                orion_setbits(GPIO_IN_POL, (1 << pin));
+                break;
+        default:
+                printk(KERN_ERR "failed to set irq=%d (type=%d)\n", irq, type);
+                return -EINVAL;
+        }
+
+        return 0;
+}
+
+static struct irq_chip orion_gpio_irq_chip = {
+        .name           = "Orion-IRQ-GPIO",
+        .ack            = orion_gpio_irq_mask,
+        .mask           = orion_gpio_irq_mask,
+        .unmask         = orion_gpio_irq_unmask,
+        .set_type       = orion_gpio_set_irq_type,
+};
+
+static void orion_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+        int i;
+        u32 cause, shift;
+
+        BUG_ON(irq < IRQ_ORION_GPIO_0_7 || irq > IRQ_ORION_GPIO_24_31);
+        shift = (irq - IRQ_ORION_GPIO_0_7) * 8;
+        cause = orion_read(GPIO_EDGE_CAUSE) & orion_read(GPIO_LEVEL_MASK);
+        cause &= (0xff << shift);
+
+        for (i = shift; i < shift + 8; i++) {
+                if (cause & (1 << i)) {
+                        int gpio_irq = i + IRQ_ORION_GPIO_START;
+                        if (gpio_irq > 0) {
+                                desc = irq_desc + gpio_irq;
+                                desc_handle_irq(gpio_irq, desc);
+                        } else {
+                                printk(KERN_ERR "orion_gpio_irq_handler error, "
+                                                "invalid irq %d\n", gpio_irq);
+                        }
+                }
+        }
+}
+
+static void __init orion_init_gpio_irq(void)
+{
+        int i;
+
+        /*
+         * Mask and clear GPIO IRQ interrupts
+         */
+        orion_write(GPIO_LEVEL_MASK, 0x0);
+        orion_write(GPIO_EDGE_CAUSE, 0x0);
+
+        /*
+         * Register chained level handlers for GPIO IRQs
+         */
+        for (i = IRQ_ORION_GPIO_START; i < NR_IRQS; i++) {
+                set_irq_chip(i, &orion_gpio_irq_chip);
+                set_irq_handler(i, handle_level_irq);
+                set_irq_flags(i, IRQF_VALID);
+        }
+        set_irq_chained_handler(IRQ_ORION_GPIO_0_7, orion_gpio_irq_handler);
+        set_irq_chained_handler(IRQ_ORION_GPIO_8_15, orion_gpio_irq_handler);
+        set_irq_chained_handler(IRQ_ORION_GPIO_16_23, orion_gpio_irq_handler);
+        set_irq_chained_handler(IRQ_ORION_GPIO_24_31, orion_gpio_irq_handler);
+}
+
+/*****************************************************************************
+ * Orion Main IRQ
+ ****************************************************************************/
+static void orion_main_irq_mask(u32 irq)
+{
+        orion_clrbits(MAIN_IRQ_MASK, 1 << irq);
+}
+
+static void orion_main_irq_unmask(u32 irq)
+{
+        orion_setbits(MAIN_IRQ_MASK, 1 << irq);
+}
+
+static struct irq_chip orion_main_irq_chip = {
+        .name           = "Orion-IRQ-Main",
+        .ack            = orion_main_irq_mask,
+        .mask           = orion_main_irq_mask,
+        .unmask         = orion_main_irq_unmask,
+};
+
+static void __init orion_init_main_irq(void)
+{
+        int i;
+
+        /*
+         * Mask and clear Main IRQ interrupts
+         */
+        orion_write(MAIN_IRQ_MASK, 0x0);
+        orion_write(MAIN_IRQ_CAUSE, 0x0);
+
+        /*
+         * Register level handler for Main IRQs
+         */
+        for (i = 0; i < IRQ_ORION_GPIO_START; i++) {
+                set_irq_chip(i, &orion_main_irq_chip);
+                set_irq_handler(i, handle_level_irq);
+                set_irq_flags(i, IRQF_VALID);
+        }
+}
+
+void __init orion_init_irq(void)
+{
+        orion_init_main_irq();
+        orion_init_gpio_irq();
+}