diff options
| author | Fabio Estevam <festevam@gmail.com> | 2013-07-23 15:13:06 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2013-07-26 12:02:09 +0100 |
| commit | 1f49856bb029779d8f1b63517a3a3b34ffe672c7 (patch) | |
| tree | 2fa00a1dc1f50c04c7c3fd339f534275e213590b | |
| parent | 8fbac214e5c594a0c2fe78c14adf2cdbb1febc92 (diff) | |
ARM: 7789/1: Do not run dummy_flush_tlb_a15_erratum() on non-Cortex-A15
Commit 93dc688 (ARM: 7684/1: errata: Workaround for Cortex-A15 erratum 798181 (TLBI/DSB operations)) causes the following undefined instruction error on a mx53 (Cortex-A8):
Internal error: Oops - undefined instruction: 0 [#1] SMP ARM
CPU: 0 PID: 275 Comm: modprobe Not tainted 3.11.0-rc2-next-20130722-00009-g9b0f371 #881
task: df46cc00 ti: df48e000 task.ti: df48e000
PC is at check_and_switch_context+0x17c/0x4d0
LR is at check_and_switch_context+0xdc/0x4d0
This problem happens because check_and_switch_context() calls dummy_flush_tlb_a15_erratum() without checking if we are really running on a Cortex-A15 or not.
To avoid this issue, only call dummy_flush_tlb_a15_erratum() inside
check_and_switch_context() if erratum_a15_798181() returns true, which means that we are really running on a Cortex-A15.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| -rw-r--r-- | arch/arm/include/asm/tlbflush.h | 16 | ||||
| -rw-r--r-- | arch/arm/kernel/smp_tlb.c | 17 | ||||
| -rw-r--r-- | arch/arm/mm/context.c | 3 |
3 files changed, 18 insertions, 18 deletions
diff --git a/arch/arm/include/asm/tlbflush.h b/arch/arm/include/asm/tlbflush.h index fdbb9e369745..f467e9b3f8d5 100644 --- a/arch/arm/include/asm/tlbflush.h +++ b/arch/arm/include/asm/tlbflush.h @@ -443,7 +443,18 @@ static inline void local_flush_bp_all(void) isb(); } +#include <asm/cputype.h> #ifdef CONFIG_ARM_ERRATA_798181 +static inline int erratum_a15_798181(void) +{ + unsigned int midr = read_cpuid_id(); + + /* Cortex-A15 r0p0..r3p2 affected */ + if ((midr & 0xff0ffff0) != 0x410fc0f0 || midr > 0x413fc0f2) + return 0; + return 1; +} + static inline void dummy_flush_tlb_a15_erratum(void) { /* @@ -453,6 +464,11 @@ static inline void dummy_flush_tlb_a15_erratum(void) dsb(); } #else +static inline int erratum_a15_798181(void) +{ + return 0; +} + static inline void dummy_flush_tlb_a15_erratum(void) { } diff --git a/arch/arm/kernel/smp_tlb.c b/arch/arm/kernel/smp_tlb.c index a98b62dca2fa..c2edfff573c2 100644 --- a/arch/arm/kernel/smp_tlb.c +++ b/arch/arm/kernel/smp_tlb.c @@ -70,23 +70,6 @@ static inline void ipi_flush_bp_all(void *ignored) local_flush_bp_all(); } -#ifdef CONFIG_ARM_ERRATA_798181 -static int erratum_a15_798181(void) -{ - unsigned int midr = read_cpuid_id(); - - /* Cortex-A15 r0p0..r3p2 affected */ - if ((midr & 0xff0ffff0) != 0x410fc0f0 || midr > 0x413fc0f2) - return 0; - return 1; -} -#else -static int erratum_a15_798181(void) -{ - return 0; -} -#endif - static void ipi_flush_tlb_a15_erratum(void *arg) { dmb(); diff --git a/arch/arm/mm/context.c b/arch/arm/mm/context.c index b55b1015724b..4a0544492f10 100644 --- a/arch/arm/mm/context.c +++ b/arch/arm/mm/context.c @@ -245,7 +245,8 @@ void check_and_switch_context(struct mm_struct *mm, struct task_struct *tsk) if (cpumask_test_and_clear_cpu(cpu, &tlb_flush_pending)) { local_flush_bp_all(); local_flush_tlb_all(); - dummy_flush_tlb_a15_erratum(); + if (erratum_a15_798181()) + dummy_flush_tlb_a15_erratum(); } atomic64_set(&per_cpu(active_asids, cpu), asid); |