AT91: pm: use plain cpu_do_idle() for "wait for interrupt"
For power management at91_pm_enter() routine, use the cpu_do_idle() for a
rock solid "wait for interrupt" implementation.
For AT91SAM9 ARM 926 based chips, we can exceed the cache line length as
we can access RAM even while in self-refresh mode.
We keep plain access to CP15 for at91rm9200 as this feature is not
available: instructions have to be in a single cache line.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index 6156689..87a31ba 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c
@@ -258,16 +258,18 @@
* NOTE: the Wait-for-Interrupt instruction needs to be
* in icache so no SDRAM accesses are needed until the
* wakeup IRQ occurs and self-refresh is terminated.
+ * For ARM 926 based chips, this requirement is weaker
+ * as at91sam9 can access a RAM in self-refresh mode.
*/
asm("b 1f; .align 5; 1:");
asm("mcr p15, 0, r0, c7, c10, 4"); /* drain write buffer */
saved_lpr = sdram_selfrefresh_enable();
- asm("mcr p15, 0, r0, c7, c0, 4"); /* wait for interrupt */
+ wait_for_interrupt_enable();
sdram_selfrefresh_disable(saved_lpr);
break;
case PM_SUSPEND_ON:
- asm("mcr p15, 0, r0, c7, c0, 4"); /* wait for interrupt */
+ cpu_do_idle();
break;
default: