powerpc: Add a cpu feature CPU_FTR_PMAO_BUG

Some power8 revisions have a hardware bug where we can lose a
Performance Monitor (PMU) exception under certain circumstances.

We will be adding a workaround for this case, see the next commit for
details. The observed behaviour is that writing PMAO doesn't cause an
exception as we would expect, hence the name of the feature.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Michael Ellerman 2014-03-14 16:00:28 +11:00 committed by Benjamin Herrenschmidt
parent 5f6d0380c6
commit 68f2f0d431
2 changed files with 5 additions and 3 deletions

View File

@ -189,6 +189,7 @@ extern const char *powerpc_base_platform;
#define CPU_FTR_HAS_PPR LONG_ASM_CONST(0x0200000000000000)
#define CPU_FTR_DAWR LONG_ASM_CONST(0x0400000000000000)
#define CPU_FTR_DABRX LONG_ASM_CONST(0x0800000000000000)
#define CPU_FTR_PMAO_BUG LONG_ASM_CONST(0x1000000000000000)
#ifndef __ASSEMBLY__
@ -445,6 +446,7 @@ extern const char *powerpc_base_platform;
CPU_FTR_ICSWX | CPU_FTR_CFAR | CPU_FTR_HVMODE | CPU_FTR_VMX_COPY | \
CPU_FTR_DBELL | CPU_FTR_HAS_PPR | CPU_FTR_DAWR | \
CPU_FTR_ARCH_207S | CPU_FTR_TM_COMP)
#define CPU_FTRS_POWER8E (CPU_FTRS_POWER8 | CPU_FTR_PMAO_BUG)
#define CPU_FTRS_CELL (CPU_FTR_USE_TB | CPU_FTR_LWSYNC | \
CPU_FTR_PPCAS_ARCH_V2 | CPU_FTR_CTRL | \
CPU_FTR_ALTIVEC_COMP | CPU_FTR_MMCRA | CPU_FTR_SMT | \
@ -466,8 +468,8 @@ extern const char *powerpc_base_platform;
#define CPU_FTRS_POSSIBLE \
(CPU_FTRS_POWER3 | CPU_FTRS_RS64 | CPU_FTRS_POWER4 | \
CPU_FTRS_PPC970 | CPU_FTRS_POWER5 | CPU_FTRS_POWER6 | \
CPU_FTRS_POWER7 | CPU_FTRS_POWER8 | CPU_FTRS_CELL | \
CPU_FTRS_PA6T | CPU_FTR_VSX)
CPU_FTRS_POWER7 | CPU_FTRS_POWER8E | CPU_FTRS_POWER8 | \
CPU_FTRS_CELL | CPU_FTRS_PA6T | CPU_FTR_VSX)
#endif
#else
enum {

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@ -510,7 +510,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.pvr_mask = 0xffff0000,
.pvr_value = 0x004b0000,
.cpu_name = "POWER8E (raw)",
.cpu_features = CPU_FTRS_POWER8,
.cpu_features = CPU_FTRS_POWER8E,
.cpu_user_features = COMMON_USER_POWER8,
.cpu_user_features2 = COMMON_USER2_POWER8,
.mmu_features = MMU_FTRS_POWER8,