ARM: orion5x: switch to DT interrupts and timer

This commit switches the Orion5x platforms described through DT to use
a DT-defined interrupt controller and timer.

This involves:

 * Describing in the DT the bridge interrupt controller, which is a
   child interrupt controller to the main one, which is used for timer
   and watchdog interrupts.

 * Describing in the DT the timer.

 * Adding in the DT the interrupt specifications for the watchdog.

 * Selecting the ORION_IRQCHIP and ORION_TIMER drivers to be compiled.

 * Change board-dt.c to no longer have an ->init_time() callback,
   since the default callback will work fine: it calls
   clocksource_of_init() and of_clk_init(), as needed.

 * Implement a multi-IRQ handler for non-DT platforms in
   mach-orion5x/irq.c.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Link: https://lkml.kernel.org/r/1398202002-28530-24-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

1 files changed, 28 insertions, 0 deletions

diff --git a/arch/arm/mach-orion5x/irq.c b/arch/arm/mach-orion5x/irq.c
index 9654b0cc589..cd4bac4d7e4 100644
--- a/arch/arm/mach-orion5x/irq.c
+++ b/arch/arm/mach-orion5x/irq.c
@@ -16,6 +16,7 @@
 #include <mach/bridge-regs.h>
 #include <plat/orion-gpio.h>
 #include <plat/irq.h>
+#include <asm/exception.h>
 #include "common.h"
 
 static int __initdata gpio0_irqs[4] = {
@@ -25,10 +26,37 @@ static int __initdata gpio0_irqs[4] = {
 	IRQ_ORION5X_GPIO_24_31,
 };
 
+#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.
+ */
+
+asmlinkage void
+__exception_irq_entry orion5x_legacy_handle_irq(struct pt_regs *regs)
+{
+	u32 stat;
+
+	stat = readl_relaxed(MAIN_IRQ_CAUSE);
+	stat &= readl_relaxed(MAIN_IRQ_MASK);
+	if (stat) {
+		unsigned int hwirq = __fls(stat);
+		handle_IRQ(hwirq, regs);
+		return;
+	}
+}
+#endif
+
 void __init orion5x_init_irq(void)
 {
 	orion_irq_init(0, MAIN_IRQ_MASK);
 
+#ifdef CONFIG_MULTI_IRQ_HANDLER
+	set_handle_irq(orion5x_legacy_handle_irq);
+#endif
+
 	/*
 	 * Initialize gpiolib for GPIOs 0-31.
 	 */