diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index 01bb5cf995af901008186726f65816b9b999d795..81217220eb92d25b9edf9b75036f4d064efeb2d0 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -144,6 +144,8 @@ void check_local_cpu_features(void); bool cpu_supports_mixed_endian_el0(void); bool system_supports_mixed_endian_el0(void); +u64 read_system_reg(u32 id); + #endif /* __ASSEMBLY__ */ #endif diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index aae181760e1f02af3c6bb55633062c557b18f5be..b4656cabf87f78f71613aee903bdf634650d729d 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -590,6 +590,15 @@ void update_cpu_features(int cpu, update_mixed_endian_el0_support(info); } +u64 read_system_reg(u32 id) +{ + struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id); + + /* We shouldn't get a request for an unsupported register */ + BUG_ON(!regp); + return regp->sys_val; +} + static bool feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry) {