From 46823dd17c676d1e1830774e93be813dc3638d6c Mon Sep 17 00:00:00 2001 From: Dave Martin Date: Thu, 23 Mar 2017 15:14:39 +0000 Subject: [PATCH] arm64: cpufeature: Make ID reg accessor naming less counterintuitive read_system_reg() can readily be confused with read_sysreg(), whereas these are really quite different in their meaning. This patches attempts to reduce the ambiguity be reserving "sysreg" for the actual system register accessors. read_system_reg() is instead renamed to read_sanitised_ftr_reg(), to make it more obvious that the Linux-defined sanitised feature register cache is being accessed here, not the underlying architectural system registers. cpufeature.c's internal __raw_read_system_reg() function is renamed in line with its actual purpose: a form of read_sysreg() that indexes on (non-compiletime-constant) encoding rather than symbolic register name. Acked-by: Mark Rutland Reviewed-by: Suzuki K Poulose Signed-off-by: Dave Martin Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/cpufeature.h | 4 ++-- arch/arm64/include/asm/hw_breakpoint.h | 4 ++-- arch/arm64/include/asm/kvm_mmu.h | 2 +- arch/arm64/kernel/cpufeature.c | 14 +++++++------- arch/arm64/kernel/debug-monitors.c | 2 +- arch/arm64/kvm/reset.c | 2 +- arch/arm64/kvm/sys_regs.c | 4 ++-- 7 files changed, 16 insertions(+), 16 deletions(-) diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index f31c48d0cd68..e7f84a7b4465 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -226,7 +226,7 @@ void update_cpu_errata_workarounds(void); void __init enable_errata_workarounds(void); void verify_local_cpu_errata_workarounds(void); -u64 read_system_reg(u32 id); +u64 read_sanitised_ftr_reg(u32 id); static inline bool cpu_supports_mixed_endian_el0(void) { @@ -240,7 +240,7 @@ static inline bool system_supports_32bit_el0(void) static inline bool system_supports_mixed_endian_el0(void) { - return id_aa64mmfr0_mixed_endian_el0(read_system_reg(SYS_ID_AA64MMFR0_EL1)); + return id_aa64mmfr0_mixed_endian_el0(read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1)); } static inline bool system_supports_fpsimd(void) diff --git a/arch/arm64/include/asm/hw_breakpoint.h b/arch/arm64/include/asm/hw_breakpoint.h index b6b167ac082b..41770766d964 100644 --- a/arch/arm64/include/asm/hw_breakpoint.h +++ b/arch/arm64/include/asm/hw_breakpoint.h @@ -149,7 +149,7 @@ static inline void ptrace_hw_copy_thread(struct task_struct *task) /* Determine number of BRP registers available. */ static inline int get_num_brps(void) { - u64 dfr0 = read_system_reg(SYS_ID_AA64DFR0_EL1); + u64 dfr0 = read_sanitised_ftr_reg(SYS_ID_AA64DFR0_EL1); return 1 + cpuid_feature_extract_unsigned_field(dfr0, ID_AA64DFR0_BRPS_SHIFT); @@ -158,7 +158,7 @@ static inline int get_num_brps(void) /* Determine number of WRP registers available. */ static inline int get_num_wrps(void) { - u64 dfr0 = read_system_reg(SYS_ID_AA64DFR0_EL1); + u64 dfr0 = read_sanitised_ftr_reg(SYS_ID_AA64DFR0_EL1); return 1 + cpuid_feature_extract_unsigned_field(dfr0, ID_AA64DFR0_WRPS_SHIFT); diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index d2293d49f555..2bc6ffa7b89b 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -308,7 +308,7 @@ static inline void __kvm_extend_hypmap(pgd_t *boot_hyp_pgd, static inline unsigned int kvm_get_vmid_bits(void) { - int reg = read_system_reg(SYS_ID_AA64MMFR1_EL1); + int reg = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); return (cpuid_feature_extract_unsigned_field(reg, ID_AA64MMFR1_VMIDBITS_SHIFT) == 2) ? 16 : 8; } diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 81a78d9331ea..3e0d4f1ab5da 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -592,7 +592,7 @@ void update_cpu_features(int cpu, * If we have AArch32, we care about 32-bit features for compat. * If the system doesn't support AArch32, don't update them. */ - if (id_aa64pfr0_32bit_el0(read_system_reg(SYS_ID_AA64PFR0_EL1)) && + if (id_aa64pfr0_32bit_el0(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) && id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) { taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu, @@ -643,7 +643,7 @@ void update_cpu_features(int cpu, "Unsupported CPU feature variation.\n"); } -u64 read_system_reg(u32 id) +u64 read_sanitised_ftr_reg(u32 id) { struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id); @@ -656,10 +656,10 @@ u64 read_system_reg(u32 id) case r: return read_sysreg_s(r) /* - * __raw_read_system_reg() - Used by a STARTING cpu before cpuinfo is populated. + * __read_sysreg_by_encoding() - Used by a STARTING cpu before cpuinfo is populated. * Read the system register on the current CPU */ -static u64 __raw_read_system_reg(u32 sys_id) +static u64 __read_sysreg_by_encoding(u32 sys_id) { switch (sys_id) { read_sysreg_case(SYS_ID_PFR0_EL1); @@ -716,9 +716,9 @@ has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope) WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible()); if (scope == SCOPE_SYSTEM) - val = read_system_reg(entry->sys_reg); + val = read_sanitised_ftr_reg(entry->sys_reg); else - val = __raw_read_system_reg(entry->sys_reg); + val = __read_sysreg_by_encoding(entry->sys_reg); return feature_matches(val, entry); } @@ -768,7 +768,7 @@ static bool hyp_offset_low(const struct arm64_cpu_capabilities *entry, static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused) { - u64 pfr0 = read_system_reg(SYS_ID_AA64PFR0_EL1); + u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); return cpuid_feature_extract_signed_field(pfr0, ID_AA64PFR0_FP_SHIFT) < 0; diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c index 32913567da08..d618e25c3de1 100644 --- a/arch/arm64/kernel/debug-monitors.c +++ b/arch/arm64/kernel/debug-monitors.c @@ -36,7 +36,7 @@ /* Determine debug architecture. */ u8 debug_monitors_arch(void) { - return cpuid_feature_extract_unsigned_field(read_system_reg(SYS_ID_AA64DFR0_EL1), + return cpuid_feature_extract_unsigned_field(read_sanitised_ftr_reg(SYS_ID_AA64DFR0_EL1), ID_AA64DFR0_DEBUGVER_SHIFT); } diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c index d9e9697de1b2..561badf93de8 100644 --- a/arch/arm64/kvm/reset.c +++ b/arch/arm64/kvm/reset.c @@ -60,7 +60,7 @@ static bool cpu_has_32bit_el1(void) { u64 pfr0; - pfr0 = read_system_reg(SYS_ID_AA64PFR0_EL1); + pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); return !!(pfr0 & 0x20); } diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 0e26f8c2b56f..26b0e77878b5 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1183,8 +1183,8 @@ static bool trap_dbgidr(struct kvm_vcpu *vcpu, if (p->is_write) { return ignore_write(vcpu, p); } else { - u64 dfr = read_system_reg(SYS_ID_AA64DFR0_EL1); - u64 pfr = read_system_reg(SYS_ID_AA64PFR0_EL1); + u64 dfr = read_sanitised_ftr_reg(SYS_ID_AA64DFR0_EL1); + u64 pfr = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); u32 el3 = !!cpuid_feature_extract_unsigned_field(pfr, ID_AA64PFR0_EL3_SHIFT); p->regval = ((((dfr >> ID_AA64DFR0_WRPS_SHIFT) & 0xf) << 28) | -- 2.30.2