diff options
Diffstat (limited to 'arch/arm64/kernel/cpufeature.c')
| -rw-r--r-- | arch/arm64/kernel/cpufeature.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 611e8921c3d4..e238b7932096 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -192,6 +192,7 @@ static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = { }; static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = { + ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_FWB_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_AT_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LVA_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IESB_SHIFT, 4, 0), @@ -1026,6 +1027,14 @@ static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused) } #endif +static void cpu_has_fwb(const struct arm64_cpu_capabilities *__unused) +{ + u64 val = read_sysreg_s(SYS_CLIDR_EL1); + + /* Check that CLIDR_EL1.LOU{U,IS} are both 0 */ + WARN_ON(val & (7 << 27 | 7 << 21)); +} + static const struct arm64_cpu_capabilities arm64_features[] = { { .desc = "GIC system register CPU interface", @@ -1182,6 +1191,17 @@ static const struct arm64_cpu_capabilities arm64_features[] = { .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cache_dic, }, + { + .desc = "Stage-2 Force Write-Back", + .type = ARM64_CPUCAP_SYSTEM_FEATURE, + .capability = ARM64_HAS_STAGE2_FWB, + .sys_reg = SYS_ID_AA64MMFR2_EL1, + .sign = FTR_UNSIGNED, + .field_pos = ID_AA64MMFR2_FWB_SHIFT, + .min_field_value = 1, + .matches = has_cpuid_feature, + .cpu_enable = cpu_has_fwb, + }, #ifdef CONFIG_ARM64_HW_AFDBM { /* |