On Tue, Feb 15, 2011 at 3:04 AM, Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx> wrote: > On Fri, Feb 11, 2011 at 06:50:57PM -0800, Colin Cross wrote: >> > +ENDPROC(cpu_resume_turn_mmu_on) >> > +cpu_resume_after_mmu: >> > + str r5, [r2, r4, lsl #2] @ restore old mapping >> > +#ifdef MULTI_CACHE >> > + ldr r10, =cpu_cache >> > + ldr pc, [r10, #CACHE_FLUSH_KERN_ALL] >> > +#else >> > + b __cpuc_flush_kern_all >> > +#endif > > I think we can eliminate this cache flush by delaying the cache enable > as below. Could you see whether Tegra 2 survives this please? > Thanks. > > diff --git a/arch/arm/kernel/sleep.S b/arch/arm/kernel/sleep.S > index bed1876..193be5f 100644 > --- a/arch/arm/kernel/sleep.S > +++ b/arch/arm/kernel/sleep.S > @@ -4,6 +4,7 @@ > #include <asm/assembler.h> > #include <asm/glue-cache.h> > #include <asm/glue-proc.h> > +#include <asm/system.h> > .text > > /* > @@ -81,25 +82,22 @@ ENTRY(cpu_resume_mmu) > str r3, [r2, r4, lsl #2] @ setup 1:1 mapping for mmu code > sub r2, r2, r1 > ldr r3, =cpu_resume_after_mmu > + bic r1, r0, #CR_C @ ensure D-cache is disabled > b cpu_resume_turn_mmu_on > ENDPROC(cpu_resume_mmu) > .ltorg > .align 5 > cpu_resume_turn_mmu_on: > - mcr p15, 0, r0, c1, c0, 0 @ turn on MMU, caches, etc > - mrc p15, 0, r0, c0, c0, 0 @ read id reg > - mov r0, r0 > - mov r0, r0 > + mcr p15, 0, r1, c1, c0, 0 @ turn on MMU, I-cache, etc > + mrc p15, 0, r1, c0, c0, 0 @ read id reg > + mov r1, r1 > + mov r1, r1 > mov pc, r3 @ jump to virtual address > ENDPROC(cpu_resume_turn_mmu_on) > cpu_resume_after_mmu: > str r5, [r2, r4, lsl #2] @ restore old mapping > -#ifdef MULTI_CACHE > - ldr r10, =cpu_cache > - ldr pc, [r10, #CACHE_FLUSH_KERN_ALL] > -#else > - b __cpuc_flush_kern_all > -#endif > + mcr p15, 0, r0, c1, c0, 0 @ turn on D-cache > + mov pc, lr > > /* > * Note: Yes, part of the following code is located into the .data section. > > Tested-by: Colin Cross <ccross@xxxxxxxxxxx> Works for Tegra 2 cpuidle and suspend. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
