// SPDX-License-Identifier: GPL-2.0-only /* * Contains CPU feature definitions * * Copyright (C) 2015 ARM Ltd. * * A note for the weary kernel hacker: the code here is confusing and hard to * follow! That's partly because it's solving a nasty problem, but also because * there's a little bit of over-abstraction that tends to obscure what's going * on behind a maze of helper functions and macros. * * The basic problem is that hardware folks have started gluing together CPUs * with distinct architectural features; in some cases even creating SoCs where * user-visible instructions are available only on a subset of the available * cores. We try to address this by snapshotting the feature registers of the * boot CPU and comparing these with the feature registers of each secondary * CPU when bringing them up. If there is a mismatch, then we update the * snapshot state to indicate the lowest-common denominator of the feature, * known as the "safe" value. This snapshot state can be queried to view the * "sanitised" value of a feature register. * * The sanitised register values are used to decide which capabilities we * have in the system. These may be in the form of traditional "hwcaps" * advertised to userspace or internal "cpucaps" which are used to configure * things like alternative patching and static keys. While a feature mismatch * may result in a TAINT_CPU_OUT_OF_SPEC kernel taint, a capability mismatch * may prevent a CPU from being onlined at all. * * Some implementation details worth remembering: * * - Mismatched features are *always* sanitised to a "safe" value, which * usually indicates that the feature is not supported. * * - A mismatched feature marked with FTR_STRICT will cause a "SANITY CHECK" * warning when onlining an offending CPU and the kernel will be tainted * with TAINT_CPU_OUT_OF_SPEC. * * - Features marked as FTR_VISIBLE have their sanitised value visible to * userspace. FTR_VISIBLE features in registers that are only visible * to EL0 by trapping *must* have a corresponding HWCAP so that late * onlining of CPUs cannot lead to features disappearing at runtime. * * - A "feature" is typically a 4-bit register field. A "capability" is the * high-level description derived from the sanitised field value. * * - Read the Arm ARM (DDI 0487F.a) section D13.1.3 ("Principles of the ID * scheme for fields in ID registers") to understand when feature fields * may be signed or unsigned (FTR_SIGNED and FTR_UNSIGNED accordingly). * * - KVM exposes its own view of the feature registers to guest operating * systems regardless of FTR_VISIBLE. This is typically driven from the * sanitised register values to allow virtual CPUs to be migrated between * arbitrary physical CPUs, but some features not present on the host are * also advertised and emulated. Look at sys_reg_descs[] for the gory * details. * * - If the arm64_ftr_bits[] for a register has a missing field, then this * field is treated as STRICT RES0, including for read_sanitised_ftr_reg(). * This is stronger than FTR_HIDDEN and can be used to hide features from * KVM guests. */ #define pr_fmt(fmt) "CPU features: " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* Kernel representation of AT_HWCAP and AT_HWCAP2 */ static unsigned long elf_hwcap __read_mostly; #ifdef CONFIG_COMPAT #define COMPAT_ELF_HWCAP_DEFAULT \ (COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\ COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\ COMPAT_HWCAP_TLS|COMPAT_HWCAP_IDIV|\ COMPAT_HWCAP_LPAE) unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT; unsigned int compat_elf_hwcap2 __read_mostly; #endif DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS); EXPORT_SYMBOL(cpu_hwcaps); static struct arm64_cpu_capabilities const __ro_after_init *cpu_hwcaps_ptrs[ARM64_NCAPS]; /* Need also bit for ARM64_CB_PATCH */ DECLARE_BITMAP(boot_capabilities, ARM64_NPATCHABLE); bool arm64_use_ng_mappings = false; EXPORT_SYMBOL(arm64_use_ng_mappings); /* * Flag to indicate if we have computed the system wide * capabilities based on the boot time active CPUs. This * will be used to determine if a new booting CPU should * go through the verification process to make sure that it * supports the system capabilities, without using a hotplug * notifier. This is also used to decide if we could use * the fast path for checking constant CPU caps. */ DEFINE_STATIC_KEY_FALSE(arm64_const_caps_ready); EXPORT_SYMBOL(arm64_const_caps_ready); static inline void finalize_system_capabilities(void) { static_branch_enable(&arm64_const_caps_ready); } static int dump_cpu_hwcaps(struct notifier_block *self, unsigned long v, void *p) { /* file-wide pr_fmt adds "CPU features: " prefix */ pr_emerg("0x%*pb\n", ARM64_NCAPS, &cpu_hwcaps); return 0; } static struct notifier_block cpu_hwcaps_notifier = { .notifier_call = dump_cpu_hwcaps }; static int __init register_cpu_hwcaps_dumper(void) { atomic_notifier_chain_register(&panic_notifier_list, &cpu_hwcaps_notifier); return 0; } __initcall(register_cpu_hwcaps_dumper); DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS); EXPORT_SYMBOL(cpu_hwcap_keys); #define __ARM64_FTR_BITS(SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \ { \ .sign = SIGNED, \ .visible = VISIBLE, \ .strict = STRICT, \ .type = TYPE, \ .shift = SHIFT, \ .width = WIDTH, \ .safe_val = SAFE_VAL, \ } /* Define a feature with unsigned values */ #define ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \ __ARM64_FTR_BITS(FTR_UNSIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) /* Define a feature with a signed value */ #define S_ARM64_FTR_BITS(VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) \ __ARM64_FTR_BITS(FTR_SIGNED, VISIBLE, STRICT, TYPE, SHIFT, WIDTH, SAFE_VAL) #define ARM64_FTR_END \ { \ .width = 0, \ } /* meta feature for alternatives */ static bool __maybe_unused cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused); static void cpu_enable_cnp(struct arm64_cpu_capabilities const *cap); static bool __system_matches_cap(unsigned int n); /* * NOTE: Any changes to the visibility of features should be kept in * sync with the documentation of the CPU feature register ABI. */ static const struct arm64_ftr_bits ftr_id_aa64isar0[] = { ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RNDR_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TLB_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_TS_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_FHM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_DP_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM4_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SM3_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA3_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_RDM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_ATOMICS_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA2_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_SHA1_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_AES_SHIFT, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_aa64isar1[] = { ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_I8MM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DGH_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_BF16_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SPECRES_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SB_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FRINTTS_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPI_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPA_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_LRCPC_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FCMA_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_JSCVT_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_API_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_APA_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DPB_SHIFT, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV3_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV2_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_DIT_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_AMU_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_MPAM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SEL2_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SVE_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_RAS_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_GIC_SHIFT, 4, 0), S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_ASIMD_SHIFT, 4, ID_AA64PFR0_ASIMD_NI), S_ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_FP_SHIFT, 4, ID_AA64PFR0_FP_NI), ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL3_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL2_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_EL1_64BIT_ONLY), ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_EL0_64BIT_ONLY), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MPAMFRAC_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_RASFRAC_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_SSBS_SHIFT, 4, ID_AA64PFR1_SSBS_PSTATE_NI), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = { ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F64MM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_F32MM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_I8MM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SM4_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SHA3_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BF16_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_BITPERM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_AES_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ZFR0_SVEVER_SHIFT, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = { /* * We already refuse to boot CPUs that don't support our configured * page size, so we can only detect mismatches for a page size other * than the one we're currently using. Unfortunately, SoCs like this * exist in the wild so, even though we don't like it, we'll have to go * along with it and treat them as non-strict. */ S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI), S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI), ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0), /* Linux shouldn't care about secure memory */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ASID_SHIFT, 4, 0), /* * Differing PARange is fine as long as all peripherals and memory are mapped * within the minimum PARange of all CPUs */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_PARANGE_SHIFT, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_PAN_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_LOR_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HPD_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VHE_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_HADBS_SHIFT, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_E0PD_SHIFT, 4, 0), 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_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_IESB_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LSM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_UAO_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_CNP_SHIFT, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_ctr[] = { ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DIC_SHIFT, 1, 1), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IDC_SHIFT, 1, 1), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_CWG_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_ERG_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DMINLINE_SHIFT, 4, 1), /* * Linux can handle differing I-cache policies. Userspace JITs will * make use of *minLine. * If we have differing I-cache policies, report it as the weakest - VIPT. */ ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_EXACT, 14, 2, ICACHE_POLICY_VIPT), /* L1Ip */ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IMINLINE_SHIFT, 4, 0), ARM64_FTR_END, }; struct arm64_ftr_reg arm64_ftr_reg_ctrel0 = { .name = "SYS_CTR_EL0", .ftr_bits = ftr_ctr }; static const struct arm64_ftr_bits ftr_id_mmfr0[] = { S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0xf), /* InnerShr */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0), /* FCSE */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, 20, 4, 0), /* AuxReg */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0), /* TCM */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0), /* ShareLvl */ S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0xf), /* OuterShr */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0), /* PMSA */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0), /* VMSA */ ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = { S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 36, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_PMSVER_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_CTX_CMPS_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_WRPS_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_BRPS_SHIFT, 4, 0), /* * We can instantiate multiple PMU instances with different levels * of support. */ S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_TRACEVER_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_mvfr2[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0), /* FPMisc */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0), /* SIMDMisc */ ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_dczid[] = { ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 4, 1, 1), /* DZP */ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0), /* BS */ ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_isar0[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DIVIDE_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_DEBUG_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_COPROC_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_CMPBRANCH_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITFIELD_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_BITCOUNT_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR0_SWAP_SHIFT, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_isar5[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_RDM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_CRC32_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA2_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SHA1_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_AES_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR5_SEVL_SHIFT, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_mmfr4[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_EVT_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CCIDX_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_LSM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_HPDS_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_CNP_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR4_XNX_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0), /* ac2 */ /* * SpecSEI = 1 indicates that the PE might generate an SError on an * external abort on speculative read. It is safe to assume that an * SError might be generated than it will not be. Hence it has been * classified as FTR_HIGHER_SAFE. */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_MMFR4_SPECSEI_SHIFT, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_isar4[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SWP_FRAC_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_PSR_M_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SYNCH_PRIM_FRAC_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_BARRIER_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_SMC_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WRITEBACK_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_WITHSHIFTS_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR4_UNPRIV_SHIFT, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_mmfr5[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_MMFR5_ETS_SHIFT, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_isar6[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_I8MM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_BF16_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SPECRES_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_SB_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_FHM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_DP_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_ISAR6_JSCVT_SHIFT, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_pfr0[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_DIT_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR0_CSV2_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0), /* State3 */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0), /* State2 */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0), /* State1 */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0), /* State0 */ ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_pfr1[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GIC_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRT_FRAC_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SEC_FRAC_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_GENTIMER_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_VIRTUALIZATION_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_MPROGMOD_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_SECURITY_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR1_PROGMOD_SHIFT, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_pfr2[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR2_SSBS_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_CSV3_SHIFT, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_dfr0[] = { /* [31:28] TraceFilt */ S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0xf), /* PerfMon */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_dfr1[] = { S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR1_MTPMU_SHIFT, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_zcr[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ZCR_ELx_LEN_SHIFT, ZCR_ELx_LEN_SIZE, 0), /* LEN */ ARM64_FTR_END, }; /* * Common ftr bits for a 32bit register with all hidden, strict * attributes, with 4bit feature fields and a default safe value of * 0. Covers the following 32bit registers: * id_isar[1-4], id_mmfr[1-3], id_pfr1, mvfr[0-1] */ static const struct arm64_ftr_bits ftr_generic_32bits[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0), ARM64_FTR_END, }; /* Table for a single 32bit feature value */ static const struct arm64_ftr_bits ftr_single32[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 32, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_raz[] = { ARM64_FTR_END, }; #define ARM64_FTR_REG(id, table) { \ .sys_id = id, \ .reg = &(struct arm64_ftr_reg){ \ .name = #id, \ .ftr_bits = &((table)[0]), \ }} static const struct __ftr_reg_entry { u32 sys_id; struct arm64_ftr_reg *reg; } arm64_ftr_regs[] = { /* Op1 = 0, CRn = 0, CRm = 1 */ ARM64_FTR_REG(SYS_ID_PFR0_EL1, ftr_id_pfr0), ARM64_FTR_REG(SYS_ID_PFR1_EL1, ftr_id_pfr1), ARM64_FTR_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0), ARM64_FTR_REG(SYS_ID_MMFR0_EL1, ftr_id_mmfr0), ARM64_FTR_REG(SYS_ID_MMFR1_EL1, ftr_generic_32bits), ARM64_FTR_REG(SYS_ID_MMFR2_EL1, ftr_generic_32bits), ARM64_FTR_REG(SYS_ID_MMFR3_EL1, ftr_generic_32bits), /* Op1 = 0, CRn = 0, CRm = 2 */ ARM64_FTR_REG(SYS_ID_ISAR0_EL1, ftr_id_isar0), ARM64_FTR_REG(SYS_ID_ISAR1_EL1, ftr_generic_32bits), ARM64_FTR_REG(SYS_ID_ISAR2_EL1, ftr_generic_32bits), ARM64_FTR_REG(SYS_ID_ISAR3_EL1, ftr_generic_32bits), ARM64_FTR_REG(SYS_ID_ISAR4_EL1, ftr_id_isar4), ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5), ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4), ARM64_FTR_REG(SYS_ID_ISAR6_EL1, ftr_id_isar6), /* Op1 = 0, CRn = 0, CRm = 3 */ ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits), ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits), ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2), ARM64_FTR_REG(SYS_ID_PFR2_EL1, ftr_id_pfr2), ARM64_FTR_REG(SYS_ID_DFR1_EL1, ftr_id_dfr1), ARM64_FTR_REG(SYS_ID_MMFR5_EL1, ftr_id_mmfr5), /* Op1 = 0, CRn = 0, CRm = 4 */ ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0), ARM64_FTR_REG(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1), ARM64_FTR_REG(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0), /* Op1 = 0, CRn = 0, CRm = 5 */ ARM64_FTR_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0), ARM64_FTR_REG(SYS_ID_AA64DFR1_EL1, ftr_raz), /* Op1 = 0, CRn = 0, CRm = 6 */ ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0), ARM64_FTR_REG(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1), /* Op1 = 0, CRn = 0, CRm = 7 */ ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0), ARM64_FTR_REG(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1), ARM64_FTR_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2), /* Op1 = 0, CRn = 1, CRm = 2 */ ARM64_FTR_REG(SYS_ZCR_EL1, ftr_zcr), /* Op1 = 3, CRn = 0, CRm = 0 */ { SYS_CTR_EL0, &arm64_ftr_reg_ctrel0 }, ARM64_FTR_REG(SYS_DCZID_EL0, ftr_dczid), /* Op1 = 3, CRn = 14, CRm = 0 */ ARM64_FTR_REG(SYS_CNTFRQ_EL0, ftr_single32), }; static int search_cmp_ftr_reg(const void *id, const void *regp) { return (int)(unsigned long)id - (int)((const struct __ftr_reg_entry *)regp)->sys_id; } /* * get_arm64_ftr_reg - Lookup a feature register entry using its * sys_reg() encoding. With the array arm64_ftr_regs sorted in the * ascending order of sys_id , we use binary search to find a matching * entry. * * returns - Upon success, matching ftr_reg entry for id. * - NULL on failure. It is upto the caller to decide * the impact of a failure. */ static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id) { const struct __ftr_reg_entry *ret; ret = bsearch((const void *)(unsigned long)sys_id, arm64_ftr_regs, ARRAY_SIZE(arm64_ftr_regs), sizeof(arm64_ftr_regs[0]), search_cmp_ftr_reg); if (ret) return ret->reg; return NULL; } static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg, s64 ftr_val) { u64 mask = arm64_ftr_mask(ftrp); reg &= ~mask; reg |= (ftr_val << ftrp->shift) & mask; return reg; } static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new, s64 cur) { s64 ret = 0; switch (ftrp->type) { case FTR_EXACT: ret = ftrp->safe_val; break; case FTR_LOWER_SAFE: ret = new < cur ? new : cur; break; case FTR_HIGHER_OR_ZERO_SAFE: if (!cur || !new) break; /* Fallthrough */ case FTR_HIGHER_SAFE: ret = new > cur ? new : cur; break; default: BUG(); } return ret; } static void __init sort_ftr_regs(void) { int i; /* Check that the array is sorted so that we can do the binary search */ for (i = 1; i < ARRAY_SIZE(arm64_ftr_regs); i++) BUG_ON(arm64_ftr_regs[i].sys_id < arm64_ftr_regs[i - 1].sys_id); } /* * Initialise the CPU feature register from Boot CPU values. * Also initiliases the strict_mask for the register. * Any bits that are not covered by an arm64_ftr_bits entry are considered * RES0 for the system-wide value, and must strictly match. */ static void __init init_cpu_ftr_reg(u32 sys_reg, u64 new) { u64 val = 0; u64 strict_mask = ~0x0ULL; u64 user_mask = 0; u64 valid_mask = 0; const struct arm64_ftr_bits *ftrp; struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg); BUG_ON(!reg); for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) { u64 ftr_mask = arm64_ftr_mask(ftrp); s64 ftr_new = arm64_ftr_value(ftrp, new); val = arm64_ftr_set_value(ftrp, val, ftr_new); valid_mask |= ftr_mask; if (!ftrp->strict) strict_mask &= ~ftr_mask; if (ftrp->visible) user_mask |= ftr_mask; else reg->user_val = arm64_ftr_set_value(ftrp, reg->user_val, ftrp->safe_val); } val &= valid_mask; reg->sys_val = val; reg->strict_mask = strict_mask; reg->user_mask = user_mask; } extern const struct arm64_cpu_capabilities arm64_errata[]; static const struct arm64_cpu_capabilities arm64_features[]; static void __init init_cpu_hwcaps_indirect_list_from_array(const struct arm64_cpu_capabilities *caps) { for (; caps->matches; caps++) { if (WARN(caps->capability >= ARM64_NCAPS, "Invalid capability %d\n", caps->capability)) continue; if (WARN(cpu_hwcaps_ptrs[caps->capability], "Duplicate entry for capability %d\n", caps->capability)) continue; cpu_hwcaps_ptrs[caps->capability] = caps; } } static void __init init_cpu_hwcaps_indirect_list(void) { init_cpu_hwcaps_indirect_list_from_array(arm64_features); init_cpu_hwcaps_indirect_list_from_array(arm64_errata); } static void __init setup_boot_cpu_capabilities(void); void __init init_cpu_features(struct cpuinfo_arm64 *info) { /* Before we start using the tables, make sure it is sorted */ sort_ftr_regs(); init_cpu_ftr_reg(SYS_CTR_EL0, info->reg_ctr); init_cpu_ftr_reg(SYS_DCZID_EL0, info->reg_dczid); init_cpu_ftr_reg(SYS_CNTFRQ_EL0, info->reg_cntfrq); init_cpu_ftr_reg(SYS_ID_AA64DFR0_EL1, info->reg_id_aa64dfr0); init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1); init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0); init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1); init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0); init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1); init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2); init_cpu_ftr_reg(SYS_ID_AA64PFR0_EL1, info->reg_id_aa64pfr0); init_cpu_ftr_reg(SYS_ID_AA64PFR1_EL1, info->reg_id_aa64pfr1); init_cpu_ftr_reg(SYS_ID_AA64ZFR0_EL1, info->reg_id_aa64zfr0); if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) { init_cpu_ftr_reg(SYS_ID_DFR0_EL1, info->reg_id_dfr0); init_cpu_ftr_reg(SYS_ID_DFR1_EL1, info->reg_id_dfr1); init_cpu_ftr_reg(SYS_ID_ISAR0_EL1, info->reg_id_isar0); init_cpu_ftr_reg(SYS_ID_ISAR1_EL1, info->reg_id_isar1); init_cpu_ftr_reg(SYS_ID_ISAR2_EL1, info->reg_id_isar2); init_cpu_ftr_reg(SYS_ID_ISAR3_EL1, info->reg_id_isar3); init_cpu_ftr_reg(SYS_ID_ISAR4_EL1, info->reg_id_isar4); init_cpu_ftr_reg(SYS_ID_ISAR5_EL1, info->reg_id_isar5); init_cpu_ftr_reg(SYS_ID_ISAR6_EL1, info->reg_id_isar6); init_cpu_ftr_reg(SYS_ID_MMFR0_EL1, info->reg_id_mmfr0); init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1); init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2); init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3); init_cpu_ftr_reg(SYS_ID_MMFR5_EL1, info->reg_id_mmfr5); init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0); init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1); init_cpu_ftr_reg(SYS_ID_PFR2_EL1, info->reg_id_pfr2); init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0); init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1); init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2); } if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) { init_cpu_ftr_reg(SYS_ZCR_EL1, info->reg_zcr); sve_init_vq_map(); } /* * Initialize the indirect array of CPU hwcaps capabilities pointers * before we handle the boot CPU below. */ init_cpu_hwcaps_indirect_list(); /* * Detect and enable early CPU capabilities based on the boot CPU, * after we have initialised the CPU feature infrastructure. */ setup_boot_cpu_capabilities(); } static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new) { const struct arm64_ftr_bits *ftrp; for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) { s64 ftr_cur = arm64_ftr_value(ftrp, reg->sys_val); s64 ftr_new = arm64_ftr_value(ftrp, new); if (ftr_cur == ftr_new) continue; /* Find a safe value */ ftr_new = arm64_ftr_safe_value(ftrp, ftr_new, ftr_cur); reg->sys_val = arm64_ftr_set_value(ftrp, reg->sys_val, ftr_new); } } static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot) { struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id); BUG_ON(!regp); update_cpu_ftr_reg(regp, val); if ((boot & regp->strict_mask) == (val & regp->strict_mask)) return 0; pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016llx, CPU%d: %#016llx\n", regp->name, boot, cpu, val); return 1; } static void relax_cpu_ftr_reg(u32 sys_id, int field) { const struct arm64_ftr_bits *ftrp; struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id); if (WARN_ON(!regp)) return; for (ftrp = regp->ftr_bits; ftrp->width; ftrp++) { if (ftrp->shift == field) { regp->strict_mask &= ~arm64_ftr_mask(ftrp); break; } } /* Bogus field? */ WARN_ON(!ftrp->width); } static int update_32bit_cpu_features(int cpu, struct cpuinfo_arm64 *info, struct cpuinfo_arm64 *boot) { int taint = 0; u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); /* * If we don't have AArch32 at all then skip the checks entirely * as the register values may be UNKNOWN and we're not going to be * using them for anything. */ if (!id_aa64pfr0_32bit_el0(pfr0)) return taint; /* * If we don't have AArch32 at EL1, then relax the strictness of * EL1-dependent register fields to avoid spurious sanity check fails. */ if (!id_aa64pfr0_32bit_el1(pfr0)) { relax_cpu_ftr_reg(SYS_ID_ISAR4_EL1, ID_ISAR4_SMC_SHIFT); relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRT_FRAC_SHIFT); relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SEC_FRAC_SHIFT); relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_VIRTUALIZATION_SHIFT); relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_SECURITY_SHIFT); relax_cpu_ftr_reg(SYS_ID_PFR1_EL1, ID_PFR1_PROGMOD_SHIFT); } taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu, info->reg_id_dfr0, boot->reg_id_dfr0); taint |= check_update_ftr_reg(SYS_ID_DFR1_EL1, cpu, info->reg_id_dfr1, boot->reg_id_dfr1); taint |= check_update_ftr_reg(SYS_ID_ISAR0_EL1, cpu, info->reg_id_isar0, boot->reg_id_isar0); taint |= check_update_ftr_reg(SYS_ID_ISAR1_EL1, cpu, info->reg_id_isar1, boot->reg_id_isar1); taint |= check_update_ftr_reg(SYS_ID_ISAR2_EL1, cpu, info->reg_id_isar2, boot->reg_id_isar2); taint |= check_update_ftr_reg(SYS_ID_ISAR3_EL1, cpu, info->reg_id_isar3, boot->reg_id_isar3); taint |= check_update_ftr_reg(SYS_ID_ISAR4_EL1, cpu, info->reg_id_isar4, boot->reg_id_isar4); taint |= check_update_ftr_reg(SYS_ID_ISAR5_EL1, cpu, info->reg_id_isar5, boot->reg_id_isar5); taint |= check_update_ftr_reg(SYS_ID_ISAR6_EL1, cpu, info->reg_id_isar6, boot->reg_id_isar6); /* * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and * ACTLR formats could differ across CPUs and therefore would have to * be trapped for virtualization anyway. */ taint |= check_update_ftr_reg(SYS_ID_MMFR0_EL1, cpu, info->reg_id_mmfr0, boot->reg_id_mmfr0); taint |= check_update_ftr_reg(SYS_ID_MMFR1_EL1, cpu, info->reg_id_mmfr1, boot->reg_id_mmfr1); taint |= check_update_ftr_reg(SYS_ID_MMFR2_EL1, cpu, info->reg_id_mmfr2, boot->reg_id_mmfr2); taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu, info->reg_id_mmfr3, boot->reg_id_mmfr3); taint |= check_update_ftr_reg(SYS_ID_MMFR5_EL1, cpu, info->reg_id_mmfr5, boot->reg_id_mmfr5); taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu, info->reg_id_pfr0, boot->reg_id_pfr0); taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu, info->reg_id_pfr1, boot->reg_id_pfr1); taint |= check_update_ftr_reg(SYS_ID_PFR2_EL1, cpu, info->reg_id_pfr2, boot->reg_id_pfr2); taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu, info->reg_mvfr0, boot->reg_mvfr0); taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu, info->reg_mvfr1, boot->reg_mvfr1); taint |= check_update_ftr_reg(SYS_MVFR2_EL1, cpu, info->reg_mvfr2, boot->reg_mvfr2); return taint; } /* * Update system wide CPU feature registers with the values from a * non-boot CPU. Also performs SANITY checks to make sure that there * aren't any insane variations from that of the boot CPU. */ void update_cpu_features(int cpu, struct cpuinfo_arm64 *info, struct cpuinfo_arm64 *boot) { int taint = 0; /* * The kernel can handle differing I-cache policies, but otherwise * caches should look identical. Userspace JITs will make use of * *minLine. */ taint |= check_update_ftr_reg(SYS_CTR_EL0, cpu, info->reg_ctr, boot->reg_ctr); /* * Userspace may perform DC ZVA instructions. Mismatched block sizes * could result in too much or too little memory being zeroed if a * process is preempted and migrated between CPUs. */ taint |= check_update_ftr_reg(SYS_DCZID_EL0, cpu, info->reg_dczid, boot->reg_dczid); /* If different, timekeeping will be broken (especially with KVM) */ taint |= check_update_ftr_reg(SYS_CNTFRQ_EL0, cpu, info->reg_cntfrq, boot->reg_cntfrq); /* * The kernel uses self-hosted debug features and expects CPUs to * support identical debug features. We presently need CTX_CMPs, WRPs, * and BRPs to be identical. * ID_AA64DFR1 is currently RES0. */ taint |= check_update_ftr_reg(SYS_ID_AA64DFR0_EL1, cpu, info->reg_id_aa64dfr0, boot->reg_id_aa64dfr0); taint |= check_update_ftr_reg(SYS_ID_AA64DFR1_EL1, cpu, info->reg_id_aa64dfr1, boot->reg_id_aa64dfr1); /* * Even in big.LITTLE, processors should be identical instruction-set * wise. */ taint |= check_update_ftr_reg(SYS_ID_AA64ISAR0_EL1, cpu, info->reg_id_aa64isar0, boot->reg_id_aa64isar0); taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu, info->reg_id_aa64isar1, boot->reg_id_aa64isar1); /* * Differing PARange support is fine as long as all peripherals and * memory are mapped within the minimum PARange of all CPUs. * Linux should not care about secure memory. */ taint |= check_update_ftr_reg(SYS_ID_AA64MMFR0_EL1, cpu, info->reg_id_aa64mmfr0, boot->reg_id_aa64mmfr0); taint |= check_update_ftr_reg(SYS_ID_AA64MMFR1_EL1, cpu, info->reg_id_aa64mmfr1, boot->reg_id_aa64mmfr1); taint |= check_update_ftr_reg(SYS_ID_AA64MMFR2_EL1, cpu, info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2); taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu, info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0); taint |= check_update_ftr_reg(SYS_ID_AA64PFR1_EL1, cpu, info->reg_id_aa64pfr1, boot->reg_id_aa64pfr1); taint |= check_update_ftr_reg(SYS_ID_AA64ZFR0_EL1, cpu, info->reg_id_aa64zfr0, boot->reg_id_aa64zfr0); if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) { taint |= check_update_ftr_reg(SYS_ZCR_EL1, cpu, info->reg_zcr, boot->reg_zcr); /* Probe vector lengths, unless we already gave up on SVE */ if (id_aa64pfr0_sve(read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) && !system_capabilities_finalized()) sve_update_vq_map(); } /* * This relies on a sanitised view of the AArch64 ID registers * (e.g. SYS_ID_AA64PFR0_EL1), so we call it last. */ taint |= update_32bit_cpu_features(cpu, info, boot); /* * Mismatched CPU features are a recipe for disaster. Don't even * pretend to support them. */ if (taint) { pr_warn_once("Unsupported CPU feature variation detected.\n"); add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK); } } u64 read_sanitised_ftr_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; } #define read_sysreg_case(r) \ case r: return read_sysreg_s(r) /* * __read_sysreg_by_encoding() - Used by a STARTING cpu before cpuinfo is populated. * Read the system register on the current CPU */ static u64 __read_sysreg_by_encoding(u32 sys_id) { switch (sys_id) { read_sysreg_case(SYS_ID_PFR0_EL1); read_sysreg_case(SYS_ID_PFR1_EL1); read_sysreg_case(SYS_ID_PFR2_EL1); read_sysreg_case(SYS_ID_DFR0_EL1); read_sysreg_case(SYS_ID_DFR1_EL1); read_sysreg_case(SYS_ID_MMFR0_EL1); read_sysreg_case(SYS_ID_MMFR1_EL1); read_sysreg_case(SYS_ID_MMFR2_EL1); read_sysreg_case(SYS_ID_MMFR3_EL1); read_sysreg_case(SYS_ID_MMFR5_EL1); read_sysreg_case(SYS_ID_ISAR0_EL1); read_sysreg_case(SYS_ID_ISAR1_EL1); read_sysreg_case(SYS_ID_ISAR2_EL1); read_sysreg_case(SYS_ID_ISAR3_EL1); read_sysreg_case(SYS_ID_ISAR4_EL1); read_sysreg_case(SYS_ID_ISAR5_EL1); read_sysreg_case(SYS_ID_ISAR6_EL1); read_sysreg_case(SYS_MVFR0_EL1); read_sysreg_case(SYS_MVFR1_EL1); read_sysreg_case(SYS_MVFR2_EL1); read_sysreg_case(SYS_ID_AA64PFR0_EL1); read_sysreg_case(SYS_ID_AA64PFR1_EL1); read_sysreg_case(SYS_ID_AA64ZFR0_EL1); read_sysreg_case(SYS_ID_AA64DFR0_EL1); read_sysreg_case(SYS_ID_AA64DFR1_EL1); read_sysreg_case(SYS_ID_AA64MMFR0_EL1); read_sysreg_case(SYS_ID_AA64MMFR1_EL1); read_sysreg_case(SYS_ID_AA64MMFR2_EL1); read_sysreg_case(SYS_ID_AA64ISAR0_EL1); read_sysreg_case(SYS_ID_AA64ISAR1_EL1); read_sysreg_case(SYS_CNTFRQ_EL0); read_sysreg_case(SYS_CTR_EL0); read_sysreg_case(SYS_DCZID_EL0); default: BUG(); return 0; } } #include static bool feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry) { int val = cpuid_feature_extract_field(reg, entry->field_pos, entry->sign); return val >= entry->min_field_value; } static bool has_cpuid_feature(const struct arm64_cpu_capabilities *entry, int scope) { u64 val; WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible()); if (scope == SCOPE_SYSTEM) val = read_sanitised_ftr_reg(entry->sys_reg); else val = __read_sysreg_by_encoding(entry->sys_reg); return feature_matches(val, entry); } static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope) { bool has_sre; if (!has_cpuid_feature(entry, scope)) return false; has_sre = gic_enable_sre(); if (!has_sre) pr_warn_once("%s present but disabled by higher exception level\n", entry->desc); return has_sre; } static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused) { u32 midr = read_cpuid_id(); /* Cavium ThunderX pass 1.x and 2.x */ return midr_is_cpu_model_range(midr, MIDR_THUNDERX, MIDR_CPU_VAR_REV(0, 0), MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK)); } static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused) { u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); return cpuid_feature_extract_signed_field(pfr0, ID_AA64PFR0_FP_SHIFT) < 0; } static bool has_cache_idc(const struct arm64_cpu_capabilities *entry, int scope) { u64 ctr; if (scope == SCOPE_SYSTEM) ctr = arm64_ftr_reg_ctrel0.sys_val; else ctr = read_cpuid_effective_cachetype(); return ctr & BIT(CTR_IDC_SHIFT); } static void cpu_emulate_effective_ctr(const struct arm64_cpu_capabilities *__unused) { /* * If the CPU exposes raw CTR_EL0.IDC = 0, while effectively * CTR_EL0.IDC = 1 (from CLIDR values), we need to trap accesses * to the CTR_EL0 on this CPU and emulate it with the real/safe * value. */ if (!(read_cpuid_cachetype() & BIT(CTR_IDC_SHIFT))) sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0); } static bool has_cache_dic(const struct arm64_cpu_capabilities *entry, int scope) { u64 ctr; if (scope == SCOPE_SYSTEM) ctr = arm64_ftr_reg_ctrel0.sys_val; else ctr = read_cpuid_cachetype(); return ctr & BIT(CTR_DIC_SHIFT); } static bool __maybe_unused has_useable_cnp(const struct arm64_cpu_capabilities *entry, int scope) { /* * Kdump isn't guaranteed to power-off all secondary CPUs, CNP * may share TLB entries with a CPU stuck in the crashed * kernel. */ if (is_kdump_kernel()) return false; return has_cpuid_feature(entry, scope); } /* * This check is triggered during the early boot before the cpufeature * is initialised. Checking the status on the local CPU allows the boot * CPU to detect the need for non-global mappings and thus avoiding a * pagetable re-write after all the CPUs are booted. This check will be * anyway run on individual CPUs, allowing us to get the consistent * state once the SMP CPUs are up and thus make the switch to non-global * mappings if required. */ bool kaslr_requires_kpti(void) { if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE)) return false; /* * E0PD does a similar job to KPTI so can be used instead * where available. */ if (IS_ENABLED(CONFIG_ARM64_E0PD)) { u64 mmfr2 = read_sysreg_s(SYS_ID_AA64MMFR2_EL1); if (cpuid_feature_extract_unsigned_field(mmfr2, ID_AA64MMFR2_E0PD_SHIFT)) return false; } /* * Systems affected by Cavium erratum 24756 are incompatible * with KPTI. */ if (IS_ENABLED(CONFIG_CAVIUM_ERRATUM_27456)) { extern const struct midr_range cavium_erratum_27456_cpus[]; if (is_midr_in_range_list(read_cpuid_id(), cavium_erratum_27456_cpus)) return false; } return kaslr_offset() > 0; } static bool __meltdown_safe = true; static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */ static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry, int scope) { /* List of CPUs that are not vulnerable and don't need KPTI */ static const struct midr_range kpti_safe_list[] = { MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2), MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN), MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53), MIDR_ALL_VERSIONS(MIDR_CORTEX_A35), MIDR_ALL_VERSIONS(MIDR_CORTEX_A53), MIDR_ALL_VERSIONS(MIDR_CORTEX_A55), MIDR_ALL_VERSIONS(MIDR_CORTEX_A57), MIDR_ALL_VERSIONS(MIDR_CORTEX_A72), MIDR_ALL_VERSIONS(MIDR_CORTEX_A73), MIDR_ALL_VERSIONS(MIDR_HISI_TSV110), MIDR_ALL_VERSIONS(MIDR_NVIDIA_CARMEL), { /* sentinel */ } }; char const *str = "kpti command line option"; bool meltdown_safe; meltdown_safe = is_midr_in_range_list(read_cpuid_id(), kpti_safe_list); /* Defer to CPU feature registers */ if (has_cpuid_feature(entry, scope)) meltdown_safe = true; if (!meltdown_safe) __meltdown_safe = false; /* * For reasons that aren't entirely clear, enabling KPTI on Cavium * ThunderX leads to apparent I-cache corruption of kernel text, which * ends as well as you might imagine. Don't even try. */ if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_27456)) { str = "ARM64_WORKAROUND_CAVIUM_27456"; __kpti_forced = -1; } /* Useful for KASLR robustness */ if (kaslr_requires_kpti()) { if (!__kpti_forced) { str = "KASLR"; __kpti_forced = 1; } } if (cpu_mitigations_off() && !__kpti_forced) { str = "mitigations=off"; __kpti_forced = -1; } if (!IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) { pr_info_once("kernel page table isolation disabled by kernel configuration\n"); return false; } /* Forced? */ if (__kpti_forced) { pr_info_once("kernel page table isolation forced %s by %s\n", __kpti_forced > 0 ? "ON" : "OFF", str); return __kpti_forced > 0; } return !meltdown_safe; } #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 static void kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused) { typedef void (kpti_remap_fn)(int, int, phys_addr_t); extern kpti_remap_fn idmap_kpti_install_ng_mappings; kpti_remap_fn *remap_fn; int cpu = smp_processor_id(); /* * We don't need to rewrite the page-tables if either we've done * it already or we have KASLR enabled and therefore have not * created any global mappings at all. */ if (arm64_use_ng_mappings) return; remap_fn = (void *)__pa_symbol(idmap_kpti_install_ng_mappings); cpu_install_idmap(); remap_fn(cpu, num_online_cpus(), __pa_symbol(swapper_pg_dir)); cpu_uninstall_idmap(); if (!cpu) arm64_use_ng_mappings = true; return; } #else static void kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused) { } #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */ static int __init parse_kpti(char *str) { bool enabled; int ret = strtobool(str, &enabled); if (ret) return ret; __kpti_forced = enabled ? 1 : -1; return 0; } early_param("kpti", parse_kpti); #ifdef CONFIG_ARM64_HW_AFDBM static inline void __cpu_enable_hw_dbm(void) { u64 tcr = read_sysreg(tcr_el1) | TCR_HD; write_sysreg(tcr, tcr_el1); isb(); } static bool cpu_has_broken_dbm(void) { /* List of CPUs which have broken DBM support. */ static const struct midr_range cpus[] = { #ifdef CONFIG_ARM64_ERRATUM_1024718 MIDR_RANGE(MIDR_CORTEX_A55, 0, 0, 1, 0), // A55 r0p0 -r1p0 #endif {}, }; return is_midr_in_range_list(read_cpuid_id(), cpus); } static bool cpu_can_use_dbm(const struct arm64_cpu_capabilities *cap) { return has_cpuid_feature(cap, SCOPE_LOCAL_CPU) && !cpu_has_broken_dbm(); } static void cpu_enable_hw_dbm(struct arm64_cpu_capabilities const *cap) { if (cpu_can_use_dbm(cap)) __cpu_enable_hw_dbm(); } static bool has_hw_dbm(const struct arm64_cpu_capabilities *cap, int __unused) { static bool detected = false; /* * DBM is a non-conflicting feature. i.e, the kernel can safely * run a mix of CPUs with and without the feature. So, we * unconditionally enable the capability to allow any late CPU * to use the feature. We only enable the control bits on the * CPU, if it actually supports. * * We have to make sure we print the "feature" detection only * when at least one CPU actually uses it. So check if this CPU * can actually use it and print the message exactly once. * * This is safe as all CPUs (including secondary CPUs - due to the * LOCAL_CPU scope - and the hotplugged CPUs - via verification) * goes through the "matches" check exactly once. Also if a CPU * matches the criteria, it is guaranteed that the CPU will turn * the DBM on, as the capability is unconditionally enabled. */ if (!detected && cpu_can_use_dbm(cap)) { detected = true; pr_info("detected: Hardware dirty bit management\n"); } return true; } #endif #ifdef CONFIG_ARM64_AMU_EXTN /* * The "amu_cpus" cpumask only signals that the CPU implementation for the * flagged CPUs supports the Activity Monitors Unit (AMU) but does not provide * information regarding all the events that it supports. When a CPU bit is * set in the cpumask, the user of this feature can only rely on the presence * of the 4 fixed counters for that CPU. But this does not guarantee that the * counters are enabled or access to these counters is enabled by code * executed at higher exception levels (firmware). */ static struct cpumask amu_cpus __read_mostly; bool cpu_has_amu_feat(int cpu) { return cpumask_test_cpu(cpu, &amu_cpus); } /* Initialize the use of AMU counters for frequency invariance */ extern void init_cpu_freq_invariance_counters(void); static void cpu_amu_enable(struct arm64_cpu_capabilities const *cap) { if (has_cpuid_feature(cap, SCOPE_LOCAL_CPU)) { pr_info("detected CPU%d: Activity Monitors Unit (AMU)\n", smp_processor_id()); cpumask_set_cpu(smp_processor_id(), &amu_cpus); init_cpu_freq_invariance_counters(); } } static bool has_amu(const struct arm64_cpu_capabilities *cap, int __unused) { /* * The AMU extension is a non-conflicting feature: the kernel can * safely run a mix of CPUs with and without support for the * activity monitors extension. Therefore, unconditionally enable * the capability to allow any late CPU to use the feature. * * With this feature unconditionally enabled, the cpu_enable * function will be called for all CPUs that match the criteria, * including secondary and hotplugged, marking this feature as * present on that respective CPU. The enable function will also * print a detection message. */ return true; } #endif #ifdef CONFIG_ARM64_VHE static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused) { return is_kernel_in_hyp_mode(); } static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused) { /* * Copy register values that aren't redirected by hardware. * * Before code patching, we only set tpidr_el1, all CPUs need to copy * this value to tpidr_el2 before we patch the code. Once we've done * that, freshly-onlined CPUs will set tpidr_el2, so we don't need to * do anything here. */ if (!alternative_is_applied(ARM64_HAS_VIRT_HOST_EXTN)) write_sysreg(read_sysreg(tpidr_el1), tpidr_el2); } #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)); } #ifdef CONFIG_ARM64_SSBD static int ssbs_emulation_handler(struct pt_regs *regs, u32 instr) { if (user_mode(regs)) return 1; if (instr & BIT(PSTATE_Imm_shift)) regs->pstate |= PSR_SSBS_BIT; else regs->pstate &= ~PSR_SSBS_BIT; arm64_skip_faulting_instruction(regs, 4); return 0; } static struct undef_hook ssbs_emulation_hook = { .instr_mask = ~(1U << PSTATE_Imm_shift), .instr_val = 0xd500401f | PSTATE_SSBS, .fn = ssbs_emulation_handler, }; static void cpu_enable_ssbs(const struct arm64_cpu_capabilities *__unused) { static bool undef_hook_registered = false; static DEFINE_RAW_SPINLOCK(hook_lock); raw_spin_lock(&hook_lock); if (!undef_hook_registered) { register_undef_hook(&ssbs_emulation_hook); undef_hook_registered = true; } raw_spin_unlock(&hook_lock); if (arm64_get_ssbd_state() == ARM64_SSBD_FORCE_DISABLE) { sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_DSSBS); arm64_set_ssbd_mitigation(false); } else { arm64_set_ssbd_mitigation(true); } } #endif /* CONFIG_ARM64_SSBD */ #ifdef CONFIG_ARM64_PAN static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused) { /* * We modify PSTATE. This won't work from irq context as the PSTATE * is discarded once we return from the exception. */ WARN_ON_ONCE(in_interrupt()); sysreg_clear_set(sctlr_el1, SCTLR_EL1_SPAN, 0); asm(SET_PSTATE_PAN(1)); } #endif /* CONFIG_ARM64_PAN */ #ifdef CONFIG_ARM64_RAS_EXTN static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused) { /* Firmware may have left a deferred SError in this register. */ write_sysreg_s(0, SYS_DISR_EL1); } #endif /* CONFIG_ARM64_RAS_EXTN */ #ifdef CONFIG_ARM64_PTR_AUTH static bool has_address_auth(const struct arm64_cpu_capabilities *entry, int __unused) { return __system_matches_cap(ARM64_HAS_ADDRESS_AUTH_ARCH) || __system_matches_cap(ARM64_HAS_ADDRESS_AUTH_IMP_DEF); } static bool has_generic_auth(const struct arm64_cpu_capabilities *entry, int __unused) { return __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH) || __system_matches_cap(ARM64_HAS_GENERIC_AUTH_IMP_DEF); } #endif /* CONFIG_ARM64_PTR_AUTH */ #ifdef CONFIG_ARM64_E0PD static void cpu_enable_e0pd(struct arm64_cpu_capabilities const *cap) { if (this_cpu_has_cap(ARM64_HAS_E0PD)) sysreg_clear_set(tcr_el1, 0, TCR_E0PD1); } #endif /* CONFIG_ARM64_E0PD */ #ifdef CONFIG_ARM64_PSEUDO_NMI static bool enable_pseudo_nmi; static int __init early_enable_pseudo_nmi(char *p) { return strtobool(p, &enable_pseudo_nmi); } early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi); static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry, int scope) { return enable_pseudo_nmi && has_useable_gicv3_cpuif(entry, scope); } #endif /* Internal helper functions to match cpu capability type */ static bool cpucap_late_cpu_optional(const struct arm64_cpu_capabilities *cap) { return !!(cap->type & ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU); } static bool cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities *cap) { return !!(cap->type & ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU); } static bool cpucap_panic_on_conflict(const struct arm64_cpu_capabilities *cap) { return !!(cap->type & ARM64_CPUCAP_PANIC_ON_CONFLICT); } static const struct arm64_cpu_capabilities arm64_features[] = { { .desc = "GIC system register CPU interface", .capability = ARM64_HAS_SYSREG_GIC_CPUIF, .type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE, .matches = has_useable_gicv3_cpuif, .sys_reg = SYS_ID_AA64PFR0_EL1, .field_pos = ID_AA64PFR0_GIC_SHIFT, .sign = FTR_UNSIGNED, .min_field_value = 1, }, #ifdef CONFIG_ARM64_PAN { .desc = "Privileged Access Never", .capability = ARM64_HAS_PAN, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64MMFR1_EL1, .field_pos = ID_AA64MMFR1_PAN_SHIFT, .sign = FTR_UNSIGNED, .min_field_value = 1, .cpu_enable = cpu_enable_pan, }, #endif /* CONFIG_ARM64_PAN */ #ifdef CONFIG_ARM64_LSE_ATOMICS { .desc = "LSE atomic instructions", .capability = ARM64_HAS_LSE_ATOMICS, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64ISAR0_EL1, .field_pos = ID_AA64ISAR0_ATOMICS_SHIFT, .sign = FTR_UNSIGNED, .min_field_value = 2, }, #endif /* CONFIG_ARM64_LSE_ATOMICS */ { .desc = "Software prefetching using PRFM", .capability = ARM64_HAS_NO_HW_PREFETCH, .type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE, .matches = has_no_hw_prefetch, }, #ifdef CONFIG_ARM64_UAO { .desc = "User Access Override", .capability = ARM64_HAS_UAO, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64MMFR2_EL1, .field_pos = ID_AA64MMFR2_UAO_SHIFT, .min_field_value = 1, /* * We rely on stop_machine() calling uao_thread_switch() to set * UAO immediately after patching. */ }, #endif /* CONFIG_ARM64_UAO */ #ifdef CONFIG_ARM64_PAN { .capability = ARM64_ALT_PAN_NOT_UAO, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = cpufeature_pan_not_uao, }, #endif /* CONFIG_ARM64_PAN */ #ifdef CONFIG_ARM64_VHE { .desc = "Virtualization Host Extensions", .capability = ARM64_HAS_VIRT_HOST_EXTN, .type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE, .matches = runs_at_el2, .cpu_enable = cpu_copy_el2regs, }, #endif /* CONFIG_ARM64_VHE */ { .desc = "32-bit EL0 Support", .capability = ARM64_HAS_32BIT_EL0, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64PFR0_EL1, .sign = FTR_UNSIGNED, .field_pos = ID_AA64PFR0_EL0_SHIFT, .min_field_value = ID_AA64PFR0_EL0_32BIT_64BIT, }, #ifdef CONFIG_KVM { .desc = "32-bit EL1 Support", .capability = ARM64_HAS_32BIT_EL1, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64PFR0_EL1, .sign = FTR_UNSIGNED, .field_pos = ID_AA64PFR0_EL1_SHIFT, .min_field_value = ID_AA64PFR0_EL1_32BIT_64BIT, }, #endif { .desc = "Kernel page table isolation (KPTI)", .capability = ARM64_UNMAP_KERNEL_AT_EL0, .type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE, /* * The ID feature fields below are used to indicate that * the CPU doesn't need KPTI. See unmap_kernel_at_el0 for * more details. */ .sys_reg = SYS_ID_AA64PFR0_EL1, .field_pos = ID_AA64PFR0_CSV3_SHIFT, .min_field_value = 1, .matches = unmap_kernel_at_el0, .cpu_enable = kpti_install_ng_mappings, }, { /* FP/SIMD is not implemented */ .capability = ARM64_HAS_NO_FPSIMD, .type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE, .min_field_value = 0, .matches = has_no_fpsimd, }, #ifdef CONFIG_ARM64_PMEM { .desc = "Data cache clean to Point of Persistence", .capability = ARM64_HAS_DCPOP, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64ISAR1_EL1, .field_pos = ID_AA64ISAR1_DPB_SHIFT, .min_field_value = 1, }, { .desc = "Data cache clean to Point of Deep Persistence", .capability = ARM64_HAS_DCPODP, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64ISAR1_EL1, .sign = FTR_UNSIGNED, .field_pos = ID_AA64ISAR1_DPB_SHIFT, .min_field_value = 2, }, #endif #ifdef CONFIG_ARM64_SVE { .desc = "Scalable Vector Extension", .type = ARM64_CPUCAP_SYSTEM_FEATURE, .capability = ARM64_SVE, .sys_reg = SYS_ID_AA64PFR0_EL1, .sign = FTR_UNSIGNED, .field_pos = ID_AA64PFR0_SVE_SHIFT, .min_field_value = ID_AA64PFR0_SVE, .matches = has_cpuid_feature, .cpu_enable = sve_kernel_enable, }, #endif /* CONFIG_ARM64_SVE */ #ifdef CONFIG_ARM64_RAS_EXTN { .desc = "RAS Extension Support", .capability = ARM64_HAS_RAS_EXTN, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64PFR0_EL1, .sign = FTR_UNSIGNED, .field_pos = ID_AA64PFR0_RAS_SHIFT, .min_field_value = ID_AA64PFR0_RAS_V1, .cpu_enable = cpu_clear_disr, }, #endif /* CONFIG_ARM64_RAS_EXTN */ #ifdef CONFIG_ARM64_AMU_EXTN { /* * The feature is enabled by default if CONFIG_ARM64_AMU_EXTN=y. * Therefore, don't provide .desc as we don't want the detection * message to be shown until at least one CPU is detected to * support the feature. */ .capability = ARM64_HAS_AMU_EXTN, .type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE, .matches = has_amu, .sys_reg = SYS_ID_AA64PFR0_EL1, .sign = FTR_UNSIGNED, .field_pos = ID_AA64PFR0_AMU_SHIFT, .min_field_value = ID_AA64PFR0_AMU, .cpu_enable = cpu_amu_enable, }, #endif /* CONFIG_ARM64_AMU_EXTN */ { .desc = "Data cache clean to the PoU not required for I/D coherence", .capability = ARM64_HAS_CACHE_IDC, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cache_idc, .cpu_enable = cpu_emulate_effective_ctr, }, { .desc = "Instruction cache invalidation not required for I/D coherence", .capability = ARM64_HAS_CACHE_DIC, .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 { /* * Since we turn this on always, we don't want the user to * think that the feature is available when it may not be. * So hide the description. * * .desc = "Hardware pagetable Dirty Bit Management", * */ .type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE, .capability = ARM64_HW_DBM, .sys_reg = SYS_ID_AA64MMFR1_EL1, .sign = FTR_UNSIGNED, .field_pos = ID_AA64MMFR1_HADBS_SHIFT, .min_field_value = 2, .matches = has_hw_dbm, .cpu_enable = cpu_enable_hw_dbm, }, #endif { .desc = "CRC32 instructions", .capability = ARM64_HAS_CRC32, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64ISAR0_EL1, .field_pos = ID_AA64ISAR0_CRC32_SHIFT, .min_field_value = 1, }, #ifdef CONFIG_ARM64_SSBD { .desc = "Speculative Store Bypassing Safe (SSBS)", .capability = ARM64_SSBS, .type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64PFR1_EL1, .field_pos = ID_AA64PFR1_SSBS_SHIFT, .sign = FTR_UNSIGNED, .min_field_value = ID_AA64PFR1_SSBS_PSTATE_ONLY, .cpu_enable = cpu_enable_ssbs, }, #endif #ifdef CONFIG_ARM64_CNP { .desc = "Common not Private translations", .capability = ARM64_HAS_CNP, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_useable_cnp, .sys_reg = SYS_ID_AA64MMFR2_EL1, .sign = FTR_UNSIGNED, .field_pos = ID_AA64MMFR2_CNP_SHIFT, .min_field_value = 1, .cpu_enable = cpu_enable_cnp, }, #endif { .desc = "Speculation barrier (SB)", .capability = ARM64_HAS_SB, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64ISAR1_EL1, .field_pos = ID_AA64ISAR1_SB_SHIFT, .sign = FTR_UNSIGNED, .min_field_value = 1, }, #ifdef CONFIG_ARM64_PTR_AUTH { .desc = "Address authentication (architected algorithm)", .capability = ARM64_HAS_ADDRESS_AUTH_ARCH, .type = ARM64_CPUCAP_BOOT_CPU_FEATURE, .sys_reg = SYS_ID_AA64ISAR1_EL1, .sign = FTR_UNSIGNED, .field_pos = ID_AA64ISAR1_APA_SHIFT, .min_field_value = ID_AA64ISAR1_APA_ARCHITECTED, .matches = has_cpuid_feature, }, { .desc = "Address authentication (IMP DEF algorithm)", .capability = ARM64_HAS_ADDRESS_AUTH_IMP_DEF, .type = ARM64_CPUCAP_BOOT_CPU_FEATURE, .sys_reg = SYS_ID_AA64ISAR1_EL1, .sign = FTR_UNSIGNED, .field_pos = ID_AA64ISAR1_API_SHIFT, .min_field_value = ID_AA64ISAR1_API_IMP_DEF, .matches = has_cpuid_feature, }, { .capability = ARM64_HAS_ADDRESS_AUTH, .type = ARM64_CPUCAP_BOOT_CPU_FEATURE, .matches = has_address_auth, }, { .desc = "Generic authentication (architected algorithm)", .capability = ARM64_HAS_GENERIC_AUTH_ARCH, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .sys_reg = SYS_ID_AA64ISAR1_EL1, .sign = FTR_UNSIGNED, .field_pos = ID_AA64ISAR1_GPA_SHIFT, .min_field_value = ID_AA64ISAR1_GPA_ARCHITECTED, .matches = has_cpuid_feature, }, { .desc = "Generic authentication (IMP DEF algorithm)", .capability = ARM64_HAS_GENERIC_AUTH_IMP_DEF, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .sys_reg = SYS_ID_AA64ISAR1_EL1, .sign = FTR_UNSIGNED, .field_pos = ID_AA64ISAR1_GPI_SHIFT, .min_field_value = ID_AA64ISAR1_GPI_IMP_DEF, .matches = has_cpuid_feature, }, { .capability = ARM64_HAS_GENERIC_AUTH, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_generic_auth, }, #endif /* CONFIG_ARM64_PTR_AUTH */ #ifdef CONFIG_ARM64_PSEUDO_NMI { /* * Depends on having GICv3 */ .desc = "IRQ priority masking", .capability = ARM64_HAS_IRQ_PRIO_MASKING, .type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE, .matches = can_use_gic_priorities, .sys_reg = SYS_ID_AA64PFR0_EL1, .field_pos = ID_AA64PFR0_GIC_SHIFT, .sign = FTR_UNSIGNED, .min_field_value = 1, }, #endif #ifdef CONFIG_ARM64_E0PD { .desc = "E0PD", .capability = ARM64_HAS_E0PD, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .sys_reg = SYS_ID_AA64MMFR2_EL1, .sign = FTR_UNSIGNED, .field_pos = ID_AA64MMFR2_E0PD_SHIFT, .matches = has_cpuid_feature, .min_field_value = 1, .cpu_enable = cpu_enable_e0pd, }, #endif #ifdef CONFIG_ARCH_RANDOM { .desc = "Random Number Generator", .capability = ARM64_HAS_RNG, .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64ISAR0_EL1, .field_pos = ID_AA64ISAR0_RNDR_SHIFT, .sign = FTR_UNSIGNED, .min_field_value = 1, }, #endif {}, }; #define HWCAP_CPUID_MATCH(reg, field, s, min_value) \ .matches = has_cpuid_feature, \ .sys_reg = reg, \ .field_pos = field, \ .sign = s, \ .min_field_value = min_value, #define __HWCAP_CAP(name, cap_type, cap) \ .desc = name, \ .type = ARM64_CPUCAP_SYSTEM_FEATURE, \ .hwcap_type = cap_type, \ .hwcap = cap, \ #define HWCAP_CAP(reg, field, s, min_value, cap_type, cap) \ { \ __HWCAP_CAP(#cap, cap_type, cap) \ HWCAP_CPUID_MATCH(reg, field, s, min_value) \ } #define HWCAP_MULTI_CAP(list, cap_type, cap) \ { \ __HWCAP_CAP(#cap, cap_type, cap) \ .matches = cpucap_multi_entry_cap_matches, \ .match_list = list, \ } #define HWCAP_CAP_MATCH(match, cap_type, cap) \ { \ __HWCAP_CAP(#cap, cap_type, cap) \ .matches = match, \ } #ifdef CONFIG_ARM64_PTR_AUTH static const struct arm64_cpu_capabilities ptr_auth_hwcap_addr_matches[] = { { HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_APA_SHIFT, FTR_UNSIGNED, ID_AA64ISAR1_APA_ARCHITECTED) }, { HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_API_SHIFT, FTR_UNSIGNED, ID_AA64ISAR1_API_IMP_DEF) }, {}, }; static const struct arm64_cpu_capabilities ptr_auth_hwcap_gen_matches[] = { { HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPA_SHIFT, FTR_UNSIGNED, ID_AA64ISAR1_GPA_ARCHITECTED) }, { HWCAP_CPUID_MATCH(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_GPI_SHIFT, FTR_UNSIGNED, ID_AA64ISAR1_GPI_IMP_DEF) }, {}, }; #endif static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = { HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_PMULL), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AES), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA1), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA2), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_SHA512), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_CRC32), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ATOMICS), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RDM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDRDM), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SHA3), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM3), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM4_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SM4), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_DP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDDP), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_FHM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDFHM), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FLAGM), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_FLAGM2), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RNDR_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RNG), HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_FP), HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FPHP), HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, KERNEL_HWCAP_ASIMD), HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDHP), HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_DIT_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DIT), HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DCPOP), HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_DCPODP), HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_JSCVT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_JSCVT), HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FCMA_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FCMA), HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_LRCPC), HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_ILRCPC), HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FRINTTS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FRINT), HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_SB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SB), HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_BF16_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_BF16), HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DGH_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DGH), HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_I8MM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_I8MM), HWCAP_CAP(SYS_ID_AA64MMFR2_EL1, ID_AA64MMFR2_AT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_USCAT), #ifdef CONFIG_ARM64_SVE HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_SVE_SHIFT, FTR_UNSIGNED, ID_AA64PFR0_SVE, CAP_HWCAP, KERNEL_HWCAP_SVE), HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SVEVER_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SVEVER_SVE2, CAP_HWCAP, KERNEL_HWCAP_SVE2), HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES, CAP_HWCAP, KERNEL_HWCAP_SVEAES), HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_AES_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_AES_PMULL, CAP_HWCAP, KERNEL_HWCAP_SVEPMULL), HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BITPERM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BITPERM, CAP_HWCAP, KERNEL_HWCAP_SVEBITPERM), HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_BF16_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_BF16, CAP_HWCAP, KERNEL_HWCAP_SVEBF16), HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SHA3_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SHA3, CAP_HWCAP, KERNEL_HWCAP_SVESHA3), HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_SM4_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_SM4, CAP_HWCAP, KERNEL_HWCAP_SVESM4), HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_I8MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_I8MM, CAP_HWCAP, KERNEL_HWCAP_SVEI8MM), HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F32MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F32MM, CAP_HWCAP, KERNEL_HWCAP_SVEF32MM), HWCAP_CAP(SYS_ID_AA64ZFR0_EL1, ID_AA64ZFR0_F64MM_SHIFT, FTR_UNSIGNED, ID_AA64ZFR0_F64MM, CAP_HWCAP, KERNEL_HWCAP_SVEF64MM), #endif HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_SSBS_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_SSBS_PSTATE_INSNS, CAP_HWCAP, KERNEL_HWCAP_SSBS), #ifdef CONFIG_ARM64_PTR_AUTH HWCAP_MULTI_CAP(ptr_auth_hwcap_addr_matches, CAP_HWCAP, KERNEL_HWCAP_PACA), HWCAP_MULTI_CAP(ptr_auth_hwcap_gen_matches, CAP_HWCAP, KERNEL_HWCAP_PACG), #endif {}, }; #ifdef CONFIG_COMPAT static bool compat_has_neon(const struct arm64_cpu_capabilities *cap, int scope) { /* * Check that all of MVFR1_EL1.{SIMDSP, SIMDInt, SIMDLS} are available, * in line with that of arm32 as in vfp_init(). We make sure that the * check is future proof, by making sure value is non-zero. */ u32 mvfr1; WARN_ON(scope == SCOPE_LOCAL_CPU && preemptible()); if (scope == SCOPE_SYSTEM) mvfr1 = read_sanitised_ftr_reg(SYS_MVFR1_EL1); else mvfr1 = read_sysreg_s(SYS_MVFR1_EL1); return cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDSP_SHIFT) && cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDINT_SHIFT) && cpuid_feature_extract_unsigned_field(mvfr1, MVFR1_SIMDLS_SHIFT); } #endif static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = { #ifdef CONFIG_COMPAT HWCAP_CAP_MATCH(compat_has_neon, CAP_COMPAT_HWCAP, COMPAT_HWCAP_NEON), HWCAP_CAP(SYS_MVFR1_EL1, MVFR1_SIMDFMAC_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv4), /* Arm v8 mandates MVFR0.FPDP == {0, 2}. So, piggy back on this for the presence of VFP support */ HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFP), HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv3), HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL), HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES), HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1), HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA2), HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_CRC32), #endif {}, }; static void __init cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap) { switch (cap->hwcap_type) { case CAP_HWCAP: cpu_set_feature(cap->hwcap); break; #ifdef CONFIG_COMPAT case CAP_COMPAT_HWCAP: compat_elf_hwcap |= (u32)cap->hwcap; break; case CAP_COMPAT_HWCAP2: compat_elf_hwcap2 |= (u32)cap->hwcap; break; #endif default: WARN_ON(1); break; } } /* Check if we have a particular HWCAP enabled */ static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap) { bool rc; switch (cap->hwcap_type) { case CAP_HWCAP: rc = cpu_have_feature(cap->hwcap); break; #ifdef CONFIG_COMPAT case CAP_COMPAT_HWCAP: rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0; break; case CAP_COMPAT_HWCAP2: rc = (compat_elf_hwcap2 & (u32)cap->hwcap) != 0; break; #endif default: WARN_ON(1); rc = false; } return rc; } static void __init setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps) { /* We support emulation of accesses to CPU ID feature registers */ cpu_set_named_feature(CPUID); for (; hwcaps->matches; hwcaps++) if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps))) cap_set_elf_hwcap(hwcaps); } static void update_cpu_capabilities(u16 scope_mask) { int i; const struct arm64_cpu_capabilities *caps; scope_mask &= ARM64_CPUCAP_SCOPE_MASK; for (i = 0; i < ARM64_NCAPS; i++) { caps = cpu_hwcaps_ptrs[i]; if (!caps || !(caps->type & scope_mask) || cpus_have_cap(caps->capability) || !caps->matches(caps, cpucap_default_scope(caps))) continue; if (caps->desc) pr_info("detected: %s\n", caps->desc); cpus_set_cap(caps->capability); if ((scope_mask & SCOPE_BOOT_CPU) && (caps->type & SCOPE_BOOT_CPU)) set_bit(caps->capability, boot_capabilities); } } /* * Enable all the available capabilities on this CPU. The capabilities * with BOOT_CPU scope are handled separately and hence skipped here. */ static int cpu_enable_non_boot_scope_capabilities(void *__unused) { int i; u16 non_boot_scope = SCOPE_ALL & ~SCOPE_BOOT_CPU; for_each_available_cap(i) { const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[i]; if (WARN_ON(!cap)) continue; if (!(cap->type & non_boot_scope)) continue; if (cap->cpu_enable) cap->cpu_enable(cap); } return 0; } /* * Run through the enabled capabilities and enable() it on all active * CPUs */ static void __init enable_cpu_capabilities(u16 scope_mask) { int i; const struct arm64_cpu_capabilities *caps; bool boot_scope; scope_mask &= ARM64_CPUCAP_SCOPE_MASK; boot_scope = !!(scope_mask & SCOPE_BOOT_CPU); for (i = 0; i < ARM64_NCAPS; i++) { unsigned int num; caps = cpu_hwcaps_ptrs[i]; if (!caps || !(caps->type & scope_mask)) continue; num = caps->capability; if (!cpus_have_cap(num)) continue; /* Ensure cpus_have_const_cap(num) works */ static_branch_enable(&cpu_hwcap_keys[num]); if (boot_scope && caps->cpu_enable) /* * Capabilities with SCOPE_BOOT_CPU scope are finalised * before any secondary CPU boots. Thus, each secondary * will enable the capability as appropriate via * check_local_cpu_capabilities(). The only exception is * the boot CPU, for which the capability must be * enabled here. This approach avoids costly * stop_machine() calls for this case. */ caps->cpu_enable(caps); } /* * For all non-boot scope capabilities, use stop_machine() * as it schedules the work allowing us to modify PSTATE, * instead of on_each_cpu() which uses an IPI, giving us a * PSTATE that disappears when we return. */ if (!boot_scope) stop_machine(cpu_enable_non_boot_scope_capabilities, NULL, cpu_online_mask); } /* * Run through the list of capabilities to check for conflicts. * If the system has already detected a capability, take necessary * action on this CPU. */ static void verify_local_cpu_caps(u16 scope_mask) { int i; bool cpu_has_cap, system_has_cap; const struct arm64_cpu_capabilities *caps; scope_mask &= ARM64_CPUCAP_SCOPE_MASK; for (i = 0; i < ARM64_NCAPS; i++) { caps = cpu_hwcaps_ptrs[i]; if (!caps || !(caps->type & scope_mask)) continue; cpu_has_cap = caps->matches(caps, SCOPE_LOCAL_CPU); system_has_cap = cpus_have_cap(caps->capability); if (system_has_cap) { /* * Check if the new CPU misses an advertised feature, * which is not safe to miss. */ if (!cpu_has_cap && !cpucap_late_cpu_optional(caps)) break; /* * We have to issue cpu_enable() irrespective of * whether the CPU has it or not, as it is enabeld * system wide. It is upto the call back to take * appropriate action on this CPU. */ if (caps->cpu_enable) caps->cpu_enable(caps); } else { /* * Check if the CPU has this capability if it isn't * safe to have when the system doesn't. */ if (cpu_has_cap && !cpucap_late_cpu_permitted(caps)) break; } } if (i < ARM64_NCAPS) { pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n", smp_processor_id(), caps->capability, caps->desc, system_has_cap, cpu_has_cap); if (cpucap_panic_on_conflict(caps)) cpu_panic_kernel(); else cpu_die_early(); } } /* * Check for CPU features that are used in early boot * based on the Boot CPU value. */ static void check_early_cpu_features(void) { verify_cpu_asid_bits(); verify_local_cpu_caps(SCOPE_BOOT_CPU); } static void verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps) { for (; caps->matches; caps++) if (cpus_have_elf_hwcap(caps) && !caps->matches(caps, SCOPE_LOCAL_CPU)) { pr_crit("CPU%d: missing HWCAP: %s\n", smp_processor_id(), caps->desc); cpu_die_early(); } } static void verify_sve_features(void) { u64 safe_zcr = read_sanitised_ftr_reg(SYS_ZCR_EL1); u64 zcr = read_zcr_features(); unsigned int safe_len = safe_zcr & ZCR_ELx_LEN_MASK; unsigned int len = zcr & ZCR_ELx_LEN_MASK; if (len < safe_len || sve_verify_vq_map()) { pr_crit("CPU%d: SVE: vector length support mismatch\n", smp_processor_id()); cpu_die_early(); } /* Add checks on other ZCR bits here if necessary */ } static void verify_hyp_capabilities(void) { u64 safe_mmfr1, mmfr0, mmfr1; int parange, ipa_max; unsigned int safe_vmid_bits, vmid_bits; if (!IS_ENABLED(CONFIG_KVM) || !IS_ENABLED(CONFIG_KVM_ARM_HOST)) return; safe_mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); mmfr0 = read_cpuid(ID_AA64MMFR0_EL1); mmfr1 = read_cpuid(ID_AA64MMFR1_EL1); /* Verify VMID bits */ safe_vmid_bits = get_vmid_bits(safe_mmfr1); vmid_bits = get_vmid_bits(mmfr1); if (vmid_bits < safe_vmid_bits) { pr_crit("CPU%d: VMID width mismatch\n", smp_processor_id()); cpu_die_early(); } /* Verify IPA range */ parange = cpuid_feature_extract_unsigned_field(mmfr0, ID_AA64MMFR0_PARANGE_SHIFT); ipa_max = id_aa64mmfr0_parange_to_phys_shift(parange); if (ipa_max < get_kvm_ipa_limit()) { pr_crit("CPU%d: IPA range mismatch\n", smp_processor_id()); cpu_die_early(); } } /* * Run through the enabled system capabilities and enable() it on this CPU. * The capabilities were decided based on the available CPUs at the boot time. * Any new CPU should match the system wide status of the capability. If the * new CPU doesn't have a capability which the system now has enabled, we * cannot do anything to fix it up and could cause unexpected failures. So * we park the CPU. */ static void verify_local_cpu_capabilities(void) { /* * The capabilities with SCOPE_BOOT_CPU are checked from * check_early_cpu_features(), as they need to be verified * on all secondary CPUs. */ verify_local_cpu_caps(SCOPE_ALL & ~SCOPE_BOOT_CPU); verify_local_elf_hwcaps(arm64_elf_hwcaps); if (system_supports_32bit_el0()) verify_local_elf_hwcaps(compat_elf_hwcaps); if (system_supports_sve()) verify_sve_features(); if (is_hyp_mode_available()) verify_hyp_capabilities(); } void check_local_cpu_capabilities(void) { /* * All secondary CPUs should conform to the early CPU features * in use by the kernel based on boot CPU. */ check_early_cpu_features(); /* * If we haven't finalised the system capabilities, this CPU gets * a chance to update the errata work arounds and local features. * Otherwise, this CPU should verify that it has all the system * advertised capabilities. */ if (!system_capabilities_finalized()) update_cpu_capabilities(SCOPE_LOCAL_CPU); else verify_local_cpu_capabilities(); } static void __init setup_boot_cpu_capabilities(void) { /* Detect capabilities with either SCOPE_BOOT_CPU or SCOPE_LOCAL_CPU */ update_cpu_capabilities(SCOPE_BOOT_CPU | SCOPE_LOCAL_CPU); /* Enable the SCOPE_BOOT_CPU capabilities alone right away */ enable_cpu_capabilities(SCOPE_BOOT_CPU); } bool this_cpu_has_cap(unsigned int n) { if (!WARN_ON(preemptible()) && n < ARM64_NCAPS) { const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n]; if (cap) return cap->matches(cap, SCOPE_LOCAL_CPU); } return false; } /* * This helper function is used in a narrow window when, * - The system wide safe registers are set with all the SMP CPUs and, * - The SYSTEM_FEATURE cpu_hwcaps may not have been set. * In all other cases cpus_have_{const_}cap() should be used. */ static bool __system_matches_cap(unsigned int n) { if (n < ARM64_NCAPS) { const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n]; if (cap) return cap->matches(cap, SCOPE_SYSTEM); } return false; } void cpu_set_feature(unsigned int num) { WARN_ON(num >= MAX_CPU_FEATURES); elf_hwcap |= BIT(num); } EXPORT_SYMBOL_GPL(cpu_set_feature); bool cpu_have_feature(unsigned int num) { WARN_ON(num >= MAX_CPU_FEATURES); return elf_hwcap & BIT(num); } EXPORT_SYMBOL_GPL(cpu_have_feature); unsigned long cpu_get_elf_hwcap(void) { /* * We currently only populate the first 32 bits of AT_HWCAP. Please * note that for userspace compatibility we guarantee that bits 62 * and 63 will always be returned as 0. */ return lower_32_bits(elf_hwcap); } unsigned long cpu_get_elf_hwcap2(void) { return upper_32_bits(elf_hwcap); } static void __init setup_system_capabilities(void) { /* * We have finalised the system-wide safe feature * registers, finalise the capabilities that depend * on it. Also enable all the available capabilities, * that are not enabled already. */ update_cpu_capabilities(SCOPE_SYSTEM); enable_cpu_capabilities(SCOPE_ALL & ~SCOPE_BOOT_CPU); } void __init setup_cpu_features(void) { u32 cwg; setup_system_capabilities(); setup_elf_hwcaps(arm64_elf_hwcaps); if (system_supports_32bit_el0()) setup_elf_hwcaps(compat_elf_hwcaps); if (system_uses_ttbr0_pan()) pr_info("emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching\n"); sve_setup(); minsigstksz_setup(); /* Advertise that we have computed the system capabilities */ finalize_system_capabilities(); /* * Check for sane CTR_EL0.CWG value. */ cwg = cache_type_cwg(); if (!cwg) pr_warn("No Cache Writeback Granule information, assuming %d\n", ARCH_DMA_MINALIGN); } static bool __maybe_unused cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused) { return (__system_matches_cap(ARM64_HAS_PAN) && !__system_matches_cap(ARM64_HAS_UAO)); } static void __maybe_unused cpu_enable_cnp(struct arm64_cpu_capabilities const *cap) { cpu_replace_ttbr1(lm_alias(swapper_pg_dir)); } /* * We emulate only the following system register space. * Op0 = 0x3, CRn = 0x0, Op1 = 0x0, CRm = [0, 4 - 7] * See Table C5-6 System instruction encodings for System register accesses, * ARMv8 ARM(ARM DDI 0487A.f) for more details. */ static inline bool __attribute_const__ is_emulated(u32 id) { return (sys_reg_Op0(id) == 0x3 && sys_reg_CRn(id) == 0x0 && sys_reg_Op1(id) == 0x0 && (sys_reg_CRm(id) == 0 || ((sys_reg_CRm(id) >= 4) && (sys_reg_CRm(id) <= 7)))); } /* * With CRm == 0, reg should be one of : * MIDR_EL1, MPIDR_EL1 or REVIDR_EL1. */ static inline int emulate_id_reg(u32 id, u64 *valp) { switch (id) { case SYS_MIDR_EL1: *valp = read_cpuid_id(); break; case SYS_MPIDR_EL1: *valp = SYS_MPIDR_SAFE_VAL; break; case SYS_REVIDR_EL1: /* IMPLEMENTATION DEFINED values are emulated with 0 */ *valp = 0; break; default: return -EINVAL; } return 0; } static int emulate_sys_reg(u32 id, u64 *valp) { struct arm64_ftr_reg *regp; if (!is_emulated(id)) return -EINVAL; if (sys_reg_CRm(id) == 0) return emulate_id_reg(id, valp); regp = get_arm64_ftr_reg(id); if (regp) *valp = arm64_ftr_reg_user_value(regp); else /* * The untracked registers are either IMPLEMENTATION DEFINED * (e.g, ID_AFR0_EL1) or reserved RAZ. */ *valp = 0; return 0; } int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt) { int rc; u64 val; rc = emulate_sys_reg(sys_reg, &val); if (!rc) { pt_regs_write_reg(regs, rt, val); arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE); } return rc; } static int emulate_mrs(struct pt_regs *regs, u32 insn) { u32 sys_reg, rt; /* * sys_reg values are defined as used in mrs/msr instruction. * shift the imm value to get the encoding. */ sys_reg = (u32)aarch64_insn_decode_immediate(AARCH64_INSN_IMM_16, insn) << 5; rt = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RT, insn); return do_emulate_mrs(regs, sys_reg, rt); } static struct undef_hook mrs_hook = { .instr_mask = 0xfff00000, .instr_val = 0xd5300000, .pstate_mask = PSR_AA32_MODE_MASK, .pstate_val = PSR_MODE_EL0t, .fn = emulate_mrs, }; static int __init enable_mrs_emulation(void) { register_undef_hook(&mrs_hook); return 0; } core_initcall(enable_mrs_emulation); ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf) { if (__meltdown_safe) return sprintf(buf, "Not affected\n"); if (arm64_kernel_unmapped_at_el0()) return sprintf(buf, "Mitigation: PTI\n"); return sprintf(buf, "Vulnerable\n"); }