ARM: orion: switch to a per-platform handle_irq() function

Moving to the Device Tree implies having CONFIG_MULTI_IRQ_HANDLER
enabled, even for non-DT platforms (if we want both DT and non-DT
platforms to be supported in a single kernel).

However, the common CONFIG_MULTI_IRQ_HANDLER handler for non-DT
platforms in plat-orion/irq.c doesn't match the needs of
Orion5x. Also, it doesn't make much sense for orion_irq_init() to
register the multi-IRQ handler: orion_irq_init() is called once for
each IRQ cause/mask tuple, while the multi-IRQ handler only needs to
be registered once.

To solve this problem, we move the multi-IRQ handle in per-platform
code: mach-kirkwood/irq.c and mach-dove/irq.c. The Orion5x variant
will be introduced in a followup commit. Of course, this code will
ultimately be completely removed once all boards are converted to the
Device Tree.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Link: https://lkml.kernel.org/r/1398202002-28530-23-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

arch/arm/mach-dove/irq.c

@@ -108,13 +108,49 @@ static int __initdata gpio2_irqs[4] = {
 	0,
 };
 
+#ifdef CONFIG_MULTI_IRQ_HANDLER
+/*
+ * Compiling with both non-DT and DT support enabled, will
+ * break asm irq handler used by non-DT boards. Therefore,
+ * we provide a C-style irq handler even for non-DT boards,
+ * if MULTI_IRQ_HANDLER is set.
+ */
+
+static void __iomem *dove_irq_base = IRQ_VIRT_BASE;
+
+static asmlinkage void
+__exception_irq_entry dove_legacy_handle_irq(struct pt_regs *regs)
+{
+	u32 stat;
+
+	stat = readl_relaxed(dove_irq_base + IRQ_CAUSE_LOW_OFF);
+	stat &= readl_relaxed(dove_irq_base + IRQ_MASK_LOW_OFF);
+	if (stat) {
+		unsigned int hwirq = __fls(stat);
+		handle_IRQ(hwirq, regs);
+		return;
+	}
+	stat = readl_relaxed(dove_irq_base + IRQ_CAUSE_HIGH_OFF);
+	stat &= readl_relaxed(dove_irq_base + IRQ_MASK_HIGH_OFF);
+	if (stat) {
+		unsigned int hwirq = 32 + __fls(stat);
+		handle_IRQ(hwirq, regs);
+		return;
+	}
+}
+#endif
+
 void __init dove_init_irq(void)
 {
 	int i;
 
 	orion_irq_init(0, IRQ_VIRT_BASE + IRQ_MASK_LOW_OFF);
 	orion_irq_init(32, IRQ_VIRT_BASE + IRQ_MASK_HIGH_OFF);
 
+#ifdef CONFIG_MULTI_IRQ_HANDLER
+	set_handle_irq(dove_legacy_handle_irq);
+#endif
+
 	/*
 	 * Initialize gpiolib for GPIOs 0-71.
 	 */

arch/arm/mach-kirkwood/irq.c

@@ -7,6 +7,7 @@
  * License version 2.  This program is licensed "as is" without any
  * warranty of any kind, whether express or implied.
  */
+#include <asm/exception.h>
 #include <linux/gpio.h>
 #include <linux/kernel.h>
 #include <linux/irq.h>
@@ -30,11 +31,47 @@ static int __initdata gpio1_irqs[4] = {
 	0,
 };
 
+#ifdef CONFIG_MULTI_IRQ_HANDLER
+/*
+ * Compiling with both non-DT and DT support enabled, will
+ * break asm irq handler used by non-DT boards. Therefore,
+ * we provide a C-style irq handler even for non-DT boards,
+ * if MULTI_IRQ_HANDLER is set.
+ */
+
+static void __iomem *kirkwood_irq_base = IRQ_VIRT_BASE;
+
+asmlinkage void
+__exception_irq_entry kirkwood_legacy_handle_irq(struct pt_regs *regs)
+{
+	u32 stat;
+
+	stat = readl_relaxed(kirkwood_irq_base + IRQ_CAUSE_LOW_OFF);
+	stat &= readl_relaxed(kirkwood_irq_base + IRQ_MASK_LOW_OFF);
+	if (stat) {
+		unsigned int hwirq = __fls(stat);
+		handle_IRQ(hwirq, regs);
+		return;
+	}
+	stat = readl_relaxed(kirkwood_irq_base + IRQ_CAUSE_HIGH_OFF);
+	stat &= readl_relaxed(kirkwood_irq_base + IRQ_MASK_HIGH_OFF);
+	if (stat) {
+		unsigned int hwirq = 32 + __fls(stat);
+		handle_IRQ(hwirq, regs);
+		return;
+	}
+}
+#endif
+
 void __init kirkwood_init_irq(void)
 {
 	orion_irq_init(0, IRQ_VIRT_BASE + IRQ_MASK_LOW_OFF);
 	orion_irq_init(32, IRQ_VIRT_BASE + IRQ_MASK_HIGH_OFF);
 
+#ifdef CONFIG_MULTI_IRQ_HANDLER
+	set_handle_irq(kirkwood_legacy_handle_irq);
+#endif
+
 	/*
 	 * Initialize gpiolib for GPIOs 0-49.
 	 */

arch/arm/plat-orion/irq.c

@@ -20,47 +20,6 @@
 #include <plat/orion-gpio.h>
 #include <mach/bridge-regs.h>
 
-#ifdef CONFIG_MULTI_IRQ_HANDLER
-/*
- * Compiling with both non-DT and DT support enabled, will
- * break asm irq handler used by non-DT boards. Therefore,
- * we provide a C-style irq handler even for non-DT boards,
- * if MULTI_IRQ_HANDLER is set.
- *
- * Notes:
- * - this is prepared for Kirkwood and Dove only, update
- *   accordingly if you add Orion5x or MV78x00.
- * - Orion5x uses different macro names and has only one
- *   set of CAUSE/MASK registers.
- * - MV78x00 uses the same macro names but has a third
- *   set of CAUSE/MASK registers.
- *
- */
-
-static void __iomem *orion_irq_base = IRQ_VIRT_BASE;
-
-asmlinkage void
-__exception_irq_entry orion_legacy_handle_irq(struct pt_regs *regs)
-{
-	u32 stat;
-
-	stat = readl_relaxed(orion_irq_base + IRQ_CAUSE_LOW_OFF);
-	stat &= readl_relaxed(orion_irq_base + IRQ_MASK_LOW_OFF);
-	if (stat) {
-		unsigned int hwirq = __fls(stat);
-		handle_IRQ(hwirq, regs);
-		return;
-	}
-	stat = readl_relaxed(orion_irq_base + IRQ_CAUSE_HIGH_OFF);
-	stat &= readl_relaxed(orion_irq_base + IRQ_MASK_HIGH_OFF);
-	if (stat) {
-		unsigned int hwirq = 32 + __fls(stat);
-		handle_IRQ(hwirq, regs);
-		return;
-	}
-}
-#endif
-
 void __init orion_irq_init(unsigned int irq_start, void __iomem *maskaddr)
 {
 	struct irq_chip_generic *gc;
@@ -78,10 +37,6 @@ void __init orion_irq_init(unsigned int irq_start, void __iomem *maskaddr)
 	ct->chip.irq_unmask = irq_gc_mask_set_bit;
 	irq_setup_generic_chip(gc, IRQ_MSK(32), IRQ_GC_INIT_MASK_CACHE,
 			       IRQ_NOREQUEST, IRQ_LEVEL | IRQ_NOPROBE);
-
-#ifdef CONFIG_MULTI_IRQ_HANDLER
-	set_handle_irq(orion_legacy_handle_irq);
-#endif
 }
 
 #ifdef CONFIG_OF