From fac2e57742d9aa3dbe41860280352efda9d5566e Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Wed, 14 Aug 2013 10:25:14 -0400 Subject: [PATCH] ARM: vexpress/MCPM: fix cache disable sequence when CONFIG_FRAME_POINTER=y If CONFIG_FRAME_POINTER=y we get the following error: arch/arm/mach-vexpress/tc2_pm.c: In function 'tc2_pm_down': arch/arm/mach-vexpress/tc2_pm.c:200:1: error: fp cannot be used in asm here Let's fix that by explicitly preserving r11 on the stack and removing it from the clobber list. Reported-by: Russell King Reviewed-by: Dave Martin Signed-off-by: Nicolas Pitre Signed-off-by: Olof Johansson --- arch/arm/mach-vexpress/dcscb.c | 16 ++++++++++++---- arch/arm/mach-vexpress/tc2_pm.c | 16 ++++++++++++---- 2 files changed, 24 insertions(+), 8 deletions(-) diff --git a/arch/arm/mach-vexpress/dcscb.c b/arch/arm/mach-vexpress/dcscb.c index 85fffa702f5b..3a6384c6c435 100644 --- a/arch/arm/mach-vexpress/dcscb.c +++ b/arch/arm/mach-vexpress/dcscb.c @@ -144,8 +144,13 @@ static void dcscb_power_down(void) * Let's do it in the safest possible way i.e. with * no memory access within the following sequence * including to the stack. + * + * Note: fp is preserved to the stack explicitly prior doing + * this since adding it to the clobber list is incompatible + * with having CONFIG_FRAME_POINTER=y. */ asm volatile( + "str fp, [sp, #-4]! \n\t" "mrc p15, 0, r0, c1, c0, 0 @ get CR \n\t" "bic r0, r0, #"__stringify(CR_C)" \n\t" "mcr p15, 0, r0, c1, c0, 0 @ set CR \n\t" @@ -156,9 +161,10 @@ static void dcscb_power_down(void) "bic r0, r0, #(1 << 6) @ disable local coherency \n\t" "mcr p15, 0, r0, c1, c0, 1 @ set AUXCR \n\t" "isb \n\t" - "dsb " + "dsb \n\t" + "ldr fp, [sp], #4" : : : "r0","r1","r2","r3","r4","r5","r6","r7", - "r9","r10","r11","lr","memory"); + "r9","r10","lr","memory"); /* * This is a harmless no-op. On platforms with a real @@ -182,6 +188,7 @@ static void dcscb_power_down(void) * Let's do it in the safest possible way as above. */ asm volatile( + "str fp, [sp, #-4]! \n\t" "mrc p15, 0, r0, c1, c0, 0 @ get CR \n\t" "bic r0, r0, #"__stringify(CR_C)" \n\t" "mcr p15, 0, r0, c1, c0, 0 @ set CR \n\t" @@ -192,9 +199,10 @@ static void dcscb_power_down(void) "bic r0, r0, #(1 << 6) @ disable local coherency \n\t" "mcr p15, 0, r0, c1, c0, 1 @ set AUXCR \n\t" "isb \n\t" - "dsb " + "dsb \n\t" + "ldr fp, [sp], #4" : : : "r0","r1","r2","r3","r4","r5","r6","r7", - "r9","r10","r11","lr","memory"); + "r9","r10","lr","memory"); } __mcpm_cpu_down(cpu, cluster); diff --git a/arch/arm/mach-vexpress/tc2_pm.c b/arch/arm/mach-vexpress/tc2_pm.c index ddd97dd4e9b7..2b7c93a724ed 100644 --- a/arch/arm/mach-vexpress/tc2_pm.c +++ b/arch/arm/mach-vexpress/tc2_pm.c @@ -150,8 +150,13 @@ static void tc2_pm_down(u64 residency) * Let's do it in the safest possible way i.e. with * no memory access within the following sequence * including the stack. + * + * Note: fp is preserved to the stack explicitly prior doing + * this since adding it to the clobber list is incompatible + * with having CONFIG_FRAME_POINTER=y. */ asm volatile( + "str fp, [sp, #-4]! \n\t" "mrc p15, 0, r0, c1, c0, 0 @ get CR \n\t" "bic r0, r0, #"__stringify(CR_C)" \n\t" "mcr p15, 0, r0, c1, c0, 0 @ set CR \n\t" @@ -162,9 +167,10 @@ static void tc2_pm_down(u64 residency) "bic r0, r0, #(1 << 6) @ disable local coherency \n\t" "mcr p15, 0, r0, c1, c0, 1 @ set AUXCR \n\t" "isb \n\t" - "dsb " + "dsb \n\t" + "ldr fp, [sp], #4" : : : "r0","r1","r2","r3","r4","r5","r6","r7", - "r9","r10","r11","lr","memory"); + "r9","r10","lr","memory"); cci_disable_port_by_cpu(mpidr); @@ -185,6 +191,7 @@ static void tc2_pm_down(u64 residency) * Let's do it in the safest possible way as above. */ asm volatile( + "str fp, [sp, #-4]! \n\t" "mrc p15, 0, r0, c1, c0, 0 @ get CR \n\t" "bic r0, r0, #"__stringify(CR_C)" \n\t" "mcr p15, 0, r0, c1, c0, 0 @ set CR \n\t" @@ -195,9 +202,10 @@ static void tc2_pm_down(u64 residency) "bic r0, r0, #(1 << 6) @ disable local coherency \n\t" "mcr p15, 0, r0, c1, c0, 1 @ set AUXCR \n\t" "isb \n\t" - "dsb " + "dsb \n\t" + "ldr fp, [sp], #4" : : : "r0","r1","r2","r3","r4","r5","r6","r7", - "r9","r10","r11","lr","memory"); + "r9","r10","lr","memory"); } __mcpm_cpu_down(cpu, cluster);