From aec9562f3db8ece218125042e0b2b7ac5b7091e7 Mon Sep 17 00:00:00 2001 From: Anders Larsen Date: Tue, 13 Apr 2010 12:05:32 +0100 Subject: [PATCH] ARM: 6053/1: AT91: Save power by disabling the processor clock when CPU is idle Disable the processor clock when the CPU is idle. This saves much more power than merely entering 'Wait for Interrupt' mode. Since JTAG-debugging doesn't work when the processor clock is switched off, make it conditional on CONFIG_DEBUG_KERNEL. Signed-off-by: Anders Larsen Acked-by: Andrew Victor Signed-off-by: Russell King --- arch/arm/mach-at91/include/mach/system.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/arch/arm/mach-at91/include/mach/system.h b/arch/arm/mach-at91/include/mach/system.h index 5268af3933c2..c80e090b3670 100644 --- a/arch/arm/mach-at91/include/mach/system.h +++ b/arch/arm/mach-at91/include/mach/system.h @@ -24,21 +24,24 @@ #include #include #include +#include static inline void arch_idle(void) { +#ifndef CONFIG_DEBUG_KERNEL /* * Disable the processor clock. The processor will be automatically * re-enabled by an interrupt or by a reset. */ -// at91_sys_write(AT91_PMC_SCDR, AT91_PMC_PCK); - + at91_sys_write(AT91_PMC_SCDR, AT91_PMC_PCK); +#else /* * Set the processor (CP15) into 'Wait for Interrupt' mode. * Unlike disabling the processor clock via the PMC (above) * this allows the processor to be woken via JTAG. */ cpu_do_idle(); +#endif } void (*at91_arch_reset)(void);