diff options
| -rw-r--r-- | Documentation/powerpc/dawr-power9.rst | 26 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/cputable.h | 10 | ||||
| -rw-r--r-- | arch/powerpc/kernel/cputable.c | 22 | ||||
| -rw-r--r-- | arch/powerpc/kernel/dt_cpu_ftrs.c | 8 |
4 files changed, 52 insertions, 14 deletions
diff --git a/Documentation/powerpc/dawr-power9.rst b/Documentation/powerpc/dawr-power9.rst index e55ac6a24b97..310f2e0cea81 100644 --- a/Documentation/powerpc/dawr-power9.rst +++ b/Documentation/powerpc/dawr-power9.rst @@ -2,15 +2,23 @@ DAWR issues on POWER9 ===================== -On POWER9 the Data Address Watchpoint Register (DAWR) can cause a checkstop -if it points to cache inhibited (CI) memory. Currently Linux has no way to -distinguish CI memory when configuring the DAWR, so (for now) the DAWR is -disabled by this commit:: - - commit 9654153158d3e0684a1bdb76dbababdb7111d5a0 - Author: Michael Neuling <mikey@neuling.org> - Date: Tue Mar 27 15:37:24 2018 +1100 - powerpc: Disable DAWR in the base POWER9 CPU features +On older POWER9 processors, the Data Address Watchpoint Register (DAWR) can +cause a checkstop if it points to cache inhibited (CI) memory. Currently Linux +has no way to distinguish CI memory when configuring the DAWR, so on affected +systems, the DAWR is disabled. + +Affected processor revisions +============================ + +This issue is only present on processors prior to v2.3. The revision can be +found in /proc/cpuinfo:: + + processor : 0 + cpu : POWER9, altivec supported + clock : 3800.000000MHz + revision : 2.3 (pvr 004e 1203) + +On a system with the issue, the DAWR is disabled as detailed below. Technical Details: ================== diff --git a/arch/powerpc/include/asm/cputable.h b/arch/powerpc/include/asm/cputable.h index 48a55cb1bf5c..549eb6dd146f 100644 --- a/arch/powerpc/include/asm/cputable.h +++ b/arch/powerpc/include/asm/cputable.h @@ -440,6 +440,10 @@ static inline void cpu_feature_keys_init(void) { } #define CPU_FTRS_POWER9_DD2_2 (CPU_FTRS_POWER9 | CPU_FTR_POWER9_DD2_1 | \ CPU_FTR_P9_TM_HV_ASSIST | \ CPU_FTR_P9_TM_XER_SO_BUG) +#define CPU_FTRS_POWER9_DD2_3 (CPU_FTRS_POWER9 | CPU_FTR_POWER9_DD2_1 | \ + CPU_FTR_P9_TM_HV_ASSIST | \ + CPU_FTR_P9_TM_XER_SO_BUG | \ + CPU_FTR_DAWR) #define CPU_FTRS_POWER10 (CPU_FTR_LWSYNC | \ CPU_FTR_PPCAS_ARCH_V2 | CPU_FTR_CTRL | CPU_FTR_ARCH_206 |\ CPU_FTR_MMCRA | CPU_FTR_SMT | \ @@ -469,14 +473,16 @@ static inline void cpu_feature_keys_init(void) { } #define CPU_FTRS_POSSIBLE \ (CPU_FTRS_POWER7 | CPU_FTRS_POWER8E | CPU_FTRS_POWER8 | \ CPU_FTR_ALTIVEC_COMP | CPU_FTR_VSX_COMP | CPU_FTRS_POWER9 | \ - CPU_FTRS_POWER9_DD2_1 | CPU_FTRS_POWER9_DD2_2 | CPU_FTRS_POWER10) + CPU_FTRS_POWER9_DD2_1 | CPU_FTRS_POWER9_DD2_2 | \ + CPU_FTRS_POWER9_DD2_3 | CPU_FTRS_POWER10) #else #define CPU_FTRS_POSSIBLE \ (CPU_FTRS_PPC970 | CPU_FTRS_POWER5 | \ CPU_FTRS_POWER6 | CPU_FTRS_POWER7 | CPU_FTRS_POWER8E | \ CPU_FTRS_POWER8 | CPU_FTRS_CELL | CPU_FTRS_PA6T | \ CPU_FTR_VSX_COMP | CPU_FTR_ALTIVEC_COMP | CPU_FTRS_POWER9 | \ - CPU_FTRS_POWER9_DD2_1 | CPU_FTRS_POWER9_DD2_2 | CPU_FTRS_POWER10) + CPU_FTRS_POWER9_DD2_1 | CPU_FTRS_POWER9_DD2_2 | \ + CPU_FTRS_POWER9_DD2_3 | CPU_FTRS_POWER10) #endif /* CONFIG_CPU_LITTLE_ENDIAN */ #endif #else diff --git a/arch/powerpc/kernel/cputable.c b/arch/powerpc/kernel/cputable.c index f9b3def5b254..a5dbfccd2047 100644 --- a/arch/powerpc/kernel/cputable.c +++ b/arch/powerpc/kernel/cputable.c @@ -487,11 +487,29 @@ static struct cpu_spec __initdata cpu_specs[] = { .machine_check_early = __machine_check_early_realmode_p9, .platform = "power9", }, - { /* Power9 DD2.2 or later */ + { /* Power9 DD2.2 */ + .pvr_mask = 0xffffefff, + .pvr_value = 0x004e0202, + .cpu_name = "POWER9 (raw)", + .cpu_features = CPU_FTRS_POWER9_DD2_2, + .cpu_user_features = COMMON_USER_POWER9, + .cpu_user_features2 = COMMON_USER2_POWER9, + .mmu_features = MMU_FTRS_POWER9, + .icache_bsize = 128, + .dcache_bsize = 128, + .num_pmcs = 6, + .pmc_type = PPC_PMC_IBM, + .oprofile_cpu_type = "ppc64/power9", + .cpu_setup = __setup_cpu_power9, + .cpu_restore = __restore_cpu_power9, + .machine_check_early = __machine_check_early_realmode_p9, + .platform = "power9", + }, + { /* Power9 DD2.3 or later */ .pvr_mask = 0xffff0000, .pvr_value = 0x004e0000, .cpu_name = "POWER9 (raw)", - .cpu_features = CPU_FTRS_POWER9_DD2_2, + .cpu_features = CPU_FTRS_POWER9_DD2_3, .cpu_user_features = COMMON_USER_POWER9, .cpu_user_features2 = COMMON_USER2_POWER9, .mmu_features = MMU_FTRS_POWER9, diff --git a/arch/powerpc/kernel/dt_cpu_ftrs.c b/arch/powerpc/kernel/dt_cpu_ftrs.c index c8e147b66d34..2ad365c21afa 100644 --- a/arch/powerpc/kernel/dt_cpu_ftrs.c +++ b/arch/powerpc/kernel/dt_cpu_ftrs.c @@ -774,20 +774,26 @@ static __init void cpufeatures_cpu_quirks(void) if ((version & 0xffffefff) == 0x004e0200) { /* DD2.0 has no feature flag */ cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG; + cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR); } else if ((version & 0xffffefff) == 0x004e0201) { cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1; cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG; + cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR); } else if ((version & 0xffffefff) == 0x004e0202) { cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_HV_ASSIST; cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_XER_SO_BUG; cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1; + cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR); + } else if ((version & 0xffffefff) == 0x004e0203) { + cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_HV_ASSIST; + cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_XER_SO_BUG; + cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1; } else if ((version & 0xffff0000) == 0x004e0000) { /* DD2.1 and up have DD2_1 */ cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1; } if ((version & 0xffff0000) == 0x004e0000) { - cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR); cur_cpu_spec->cpu_features |= CPU_FTR_P9_TIDR; } |