1 files changed, 30 insertions, 8 deletions

diff --git a/arch/arm/mach-ebsa110/core.c b/arch/arm/mach-ebsa110/core.c
index 294aad07f7a0..e400d75d11ae 100644
--- a/arch/arm/mach-ebsa110/core.c
+++ b/arch/arm/mach-ebsa110/core.c
@@ -30,10 +30,7 @@
 
 #include <asm/mach/time.h>
 
-#define IRQ_MASK		0xfe000000	/* read */
-#define IRQ_MSET		0xfe000000	/* write */
-#define IRQ_STAT		0xff000000	/* read */
-#define IRQ_MCLR		0xff000000	/* write */
+#include "core.h"
 
 static void ebsa110_mask_irq(struct irq_data *d)
 {
@@ -79,22 +76,22 @@ static struct map_desc ebsa110_io_desc[] __initdata = {
 	{	/* IRQ_STAT/IRQ_MCLR */
 		.virtual	= IRQ_STAT,
 		.pfn		= __phys_to_pfn(TRICK4_PHYS),
-		.length		= PGDIR_SIZE,
+		.length		= TRICK4_SIZE,
 		.type		= MT_DEVICE
 	}, {	/* IRQ_MASK/IRQ_MSET */
 		.virtual	= IRQ_MASK,
 		.pfn		= __phys_to_pfn(TRICK3_PHYS),
-		.length		= PGDIR_SIZE,
+		.length		= TRICK3_SIZE,
 		.type		= MT_DEVICE
 	}, {	/* SOFT_BASE */
 		.virtual	= SOFT_BASE,
 		.pfn		= __phys_to_pfn(TRICK1_PHYS),
-		.length		= PGDIR_SIZE,
+		.length		= TRICK1_SIZE,
 		.type		= MT_DEVICE
 	}, {	/* PIT_BASE */
 		.virtual	= PIT_BASE,
 		.pfn		= __phys_to_pfn(TRICK0_PHYS),
-		.length		= PGDIR_SIZE,
+		.length		= TRICK0_SIZE,
 		.type		= MT_DEVICE
 	},
 
@@ -271,8 +268,33 @@ static struct platform_device *ebsa110_devices[] = {
 	&am79c961_device,
 };
 
+/*
+ * EBSA110 idling methodology:
+ *
+ * We can not execute the "wait for interrupt" instruction since that
+ * will stop our MCLK signal (which provides the clock for the glue
+ * logic, and therefore the timer interrupt).
+ *
+ * Instead, we spin, polling the IRQ_STAT register for the occurrence
+ * of any interrupt with core clock down to the memory clock.
+ */
+static void ebsa110_idle(void)
+{
+	const char *irq_stat = (char *)0xff000000;
+
+	/* disable clock switching */
+	asm volatile ("mcr p15, 0, ip, c15, c2, 2" : : : "cc");
+
+	/* wait for an interrupt to occur */
+	while (!*irq_stat);
+
+	/* enable clock switching */
+	asm volatile ("mcr p15, 0, ip, c15, c1, 2" : : : "cc");
+}
+
 static int __init ebsa110_init(void)
 {
+	arm_pm_idle = ebsa110_idle;
 	return platform_add_devices(ebsa110_devices, ARRAY_SIZE(ebsa110_devices));
 }