From da8d02d19ffdd201af632c755a473b6df4b3e4cc Mon Sep 17 00:00:00 2001 From: "Suzuki K. Poulose" Date: Mon, 19 Oct 2015 14:24:51 +0100 Subject: [PATCH] arm64/capabilities: Make use of system wide safe value Now that we can reliably read the system wide safe value for a feature register, use that to compute the system capability. This patch also replaces the 'feature-register-specific' methods with a generic routine to check the capability. Signed-off-by: Suzuki K. Poulose Tested-by: Dave Martin Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/cpufeature.h | 1 + arch/arm64/kernel/cpufeature.c | 79 +++++++++++++++++++++-------- 2 files changed, 60 insertions(+), 20 deletions(-) diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index 1603ae84ea45..eec584e7c701 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -78,6 +78,7 @@ struct arm64_cpu_capabilities { }; struct { /* Feature register checking */ + u32 sys_reg; int field_pos; int min_field_value; }; diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index e002cadf84bf..8aff8fcbeb96 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -586,34 +586,31 @@ feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry) return val >= entry->min_field_value; } -#define __ID_FEAT_CHK(reg) \ -static bool __maybe_unused \ -has_##reg##_feature(const struct arm64_cpu_capabilities *entry) \ -{ \ - u64 val; \ - \ - val = read_cpuid(reg##_el1); \ - return feature_matches(val, entry); \ -} +static bool +has_cpuid_feature(const struct arm64_cpu_capabilities *entry) +{ + u64 val; -__ID_FEAT_CHK(id_aa64pfr0); -__ID_FEAT_CHK(id_aa64mmfr1); -__ID_FEAT_CHK(id_aa64isar0); + val = read_system_reg(entry->sys_reg); + return feature_matches(val, entry); +} static const struct arm64_cpu_capabilities arm64_features[] = { { .desc = "GIC system register CPU interface", .capability = ARM64_HAS_SYSREG_GIC_CPUIF, - .matches = has_id_aa64pfr0_feature, - .field_pos = 24, + .matches = has_cpuid_feature, + .sys_reg = SYS_ID_AA64PFR0_EL1, + .field_pos = ID_AA64PFR0_GIC_SHIFT, .min_field_value = 1, }, #ifdef CONFIG_ARM64_PAN { .desc = "Privileged Access Never", .capability = ARM64_HAS_PAN, - .matches = has_id_aa64mmfr1_feature, - .field_pos = 20, + .matches = has_cpuid_feature, + .sys_reg = SYS_ID_AA64MMFR1_EL1, + .field_pos = ID_AA64MMFR1_PAN_SHIFT, .min_field_value = 1, .enable = cpu_enable_pan, }, @@ -622,8 +619,9 @@ static const struct arm64_cpu_capabilities arm64_features[] = { { .desc = "LSE atomic instructions", .capability = ARM64_HAS_LSE_ATOMICS, - .matches = has_id_aa64isar0_feature, - .field_pos = 20, + .matches = has_cpuid_feature, + .sys_reg = SYS_ID_AA64ISAR0_EL1, + .field_pos = ID_AA64ISAR0_ATOMICS_SHIFT, .min_field_value = 2, }, #endif /* CONFIG_AS_LSE && CONFIG_ARM64_LSE_ATOMICS */ @@ -675,6 +673,47 @@ static inline void set_sys_caps_initialised(void) sys_caps_initialised = true; } +/* + * __raw_read_system_reg() - Used by a STARTING cpu before cpuinfo is populated. + */ +static u64 __raw_read_system_reg(u32 sys_id) +{ + switch (sys_id) { + case SYS_ID_PFR0_EL1: return (u64)read_cpuid(ID_PFR0_EL1); + case SYS_ID_PFR1_EL1: return (u64)read_cpuid(ID_PFR1_EL1); + case SYS_ID_DFR0_EL1: return (u64)read_cpuid(ID_DFR0_EL1); + case SYS_ID_MMFR0_EL1: return (u64)read_cpuid(ID_MMFR0_EL1); + case SYS_ID_MMFR1_EL1: return (u64)read_cpuid(ID_MMFR1_EL1); + case SYS_ID_MMFR2_EL1: return (u64)read_cpuid(ID_MMFR2_EL1); + case SYS_ID_MMFR3_EL1: return (u64)read_cpuid(ID_MMFR3_EL1); + case SYS_ID_ISAR0_EL1: return (u64)read_cpuid(ID_ISAR0_EL1); + case SYS_ID_ISAR1_EL1: return (u64)read_cpuid(ID_ISAR1_EL1); + case SYS_ID_ISAR2_EL1: return (u64)read_cpuid(ID_ISAR2_EL1); + case SYS_ID_ISAR3_EL1: return (u64)read_cpuid(ID_ISAR3_EL1); + case SYS_ID_ISAR4_EL1: return (u64)read_cpuid(ID_ISAR4_EL1); + case SYS_ID_ISAR5_EL1: return (u64)read_cpuid(ID_ISAR4_EL1); + case SYS_MVFR0_EL1: return (u64)read_cpuid(MVFR0_EL1); + case SYS_MVFR1_EL1: return (u64)read_cpuid(MVFR1_EL1); + case SYS_MVFR2_EL1: return (u64)read_cpuid(MVFR2_EL1); + + case SYS_ID_AA64PFR0_EL1: return (u64)read_cpuid(ID_AA64PFR0_EL1); + case SYS_ID_AA64PFR1_EL1: return (u64)read_cpuid(ID_AA64PFR0_EL1); + case SYS_ID_AA64DFR0_EL1: return (u64)read_cpuid(ID_AA64DFR0_EL1); + case SYS_ID_AA64DFR1_EL1: return (u64)read_cpuid(ID_AA64DFR0_EL1); + case SYS_ID_AA64MMFR0_EL1: return (u64)read_cpuid(ID_AA64MMFR0_EL1); + case SYS_ID_AA64MMFR1_EL1: return (u64)read_cpuid(ID_AA64MMFR1_EL1); + case SYS_ID_AA64ISAR0_EL1: return (u64)read_cpuid(ID_AA64ISAR0_EL1); + case SYS_ID_AA64ISAR1_EL1: return (u64)read_cpuid(ID_AA64ISAR1_EL1); + + case SYS_CNTFRQ_EL0: return (u64)read_cpuid(CNTFRQ_EL0); + case SYS_CTR_EL0: return (u64)read_cpuid(CTR_EL0); + case SYS_DCZID_EL0: return (u64)read_cpuid(DCZID_EL0); + default: + BUG(); + return 0; + } +} + /* * Park the CPU which doesn't have the capability as advertised * by the system. @@ -719,13 +758,13 @@ void verify_local_cpu_capabilities(void) caps = arm64_features; for (i = 0; caps[i].desc; i++) { - if (!cpus_have_cap(caps[i].capability)) + if (!cpus_have_cap(caps[i].capability) || !caps[i].sys_reg) continue; /* * If the new CPU misses an advertised feature, we cannot proceed * further, park the cpu. */ - if (!caps[i].matches(&caps[i])) + if (!feature_matches(__raw_read_system_reg(caps[i].sys_reg), &caps[i])) fail_incapable_cpu("arm64_features", &caps[i]); if (caps[i].enable) caps[i].enable(NULL); -- 2.20.1