From 37caf9f2a1b99d11ba71e17168d221da9ca13f24 Mon Sep 17 00:00:00 2001 From: Kumar Gala Date: Sat, 27 Aug 2011 06:14:23 -0500 Subject: [PATCH] powerpc/fsl-booke: Handle L1 D-cache parity error correctly on e500mc If the L1 D-Cache is in write shadow mode the HW will auto-recover the error. However we might still log the error and cause a machine check (if L1CSR0[CPE] - Cache error checking enable). We should only treat the non-write shadow case as non-recoverable. Signed-off-by: Kumar Gala --- arch/powerpc/include/asm/reg_booke.h | 3 +++ arch/powerpc/kernel/traps.c | 9 ++++++++- 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/reg_booke.h b/arch/powerpc/include/asm/reg_booke.h index 9ec0b39f9ddc..28cdbd9f399c 100644 --- a/arch/powerpc/include/asm/reg_booke.h +++ b/arch/powerpc/include/asm/reg_booke.h @@ -548,6 +548,9 @@ #define L1CSR1_ICFI 0x00000002 /* Instr Cache Flash Invalidate */ #define L1CSR1_ICE 0x00000001 /* Instr Cache Enable */ +/* Bit definitions for L1CSR2. */ +#define L1CSR2_DCWS 0x40000000 /* Data Cache write shadow */ + /* Bit definitions for L2CSR0. */ #define L2CSR0_L2E 0x80000000 /* L2 Cache Enable */ #define L2CSR0_L2PE 0x40000000 /* L2 Cache Parity/ECC Enable */ diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index f19d9777d3c1..4e5908264d1a 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -457,7 +457,14 @@ int machine_check_e500mc(struct pt_regs *regs) if (reason & MCSR_DCPERR_MC) { printk("Data Cache Parity Error\n"); - recoverable = 0; + + /* + * In write shadow mode we auto-recover from the error, but it + * may still get logged and cause a machine check. We should + * only treat the non-write shadow case as non-recoverable. + */ + if (!(mfspr(SPRN_L1CSR2) & L1CSR2_DCWS)) + recoverable = 0; } if (reason & MCSR_L2MMU_MHIT) {