plat-orion: share IRQ handling code

Split off Orion IRQ handling code into plat-orion/, and add
support for multiple sets of (32) interrupts.

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

2 files changed, 65 insertions, 1 deletions

diff --git a/arch/arm/plat-orion/Makefile b/arch/arm/plat-orion/Makefile
index 2327762133f7..ea4ce342a196 100644
--- a/arch/arm/plat-orion/Makefile
+++ b/arch/arm/plat-orion/Makefile
@@ -2,7 +2,7 @@
 # Makefile for the linux kernel.
 #
 
-obj-y   :=
+obj-y   := irq.o
 obj-m   :=
 obj-n   :=
 obj-    :=
diff --git a/arch/arm/plat-orion/irq.c b/arch/arm/plat-orion/irq.c
new file mode 100644
index 000000000000..c5b669d234bc
--- /dev/null
+++ b/arch/arm/plat-orion/irq.c
@@ -0,0 +1,64 @@
+/*
+ * arch/arm/plat-orion/irq.c
+ *
+ * Marvell Orion SoC IRQ handling.
+ *
+ * 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 <linux/io.h>
+#include <asm/plat-orion/irq.h>
+
+static void orion_irq_mask(u32 irq)
+{
+        void __iomem *maskaddr = get_irq_chip_data(irq);
+        u32 mask;
+
+        mask = readl(maskaddr);
+        mask &= ~(1 << (irq & 31));
+        writel(mask, maskaddr);
+}
+
+static void orion_irq_unmask(u32 irq)
+{
+        void __iomem *maskaddr = get_irq_chip_data(irq);
+        u32 mask;
+
+        mask = readl(maskaddr);
+        mask |= 1 << (irq & 31);
+        writel(mask, maskaddr);
+}
+
+static struct irq_chip orion_irq_chip = {
+        .name           = "orion_irq",
+        .ack            = orion_irq_mask,
+        .mask           = orion_irq_mask,
+        .unmask         = orion_irq_unmask,
+};
+
+void __init orion_irq_init(unsigned int irq_start, void __iomem *maskaddr)
+{
+        unsigned int i;
+
+        /*
+         * Mask all interrupts initially.
+         */
+        writel(0, maskaddr);
+
+        /*
+         * Register IRQ sources.
+         */
+        for (i = 0; i < 32; i++) {
+                unsigned int irq = irq_start + i;
+
+                set_irq_chip(irq, &orion_irq_chip);
+                set_irq_chip_data(irq, maskaddr);
+                set_irq_handler(irq, handle_level_irq);
+                set_irq_flags(irq, IRQF_VALID);
+        }
+}