/* * Contains CPU feature definitions * * Copyright (C) 2015 ARM Ltd. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #define pr_fmt(fmt) "CPU features: " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include unsigned long elf_hwcap __read_mostly; EXPORT_SYMBOL_GPL(elf_hwcap); #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_VFP|\ COMPAT_HWCAP_VFPv3|COMPAT_HWCAP_VFPv4|\ COMPAT_HWCAP_NEON|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); 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); /* * 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_EXACT, 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_aa64pfr0[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 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), /* Linux doesn't care about the EL3 */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64PFR0_EL3_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64PFR0_EL2_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64PFR0_EL1_SHIFT, 4, ID_AA64PFR0_EL1_64BIT_ONLY), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64PFR0_EL0_SHIFT, 4, ID_AA64PFR0_EL0_64BIT_ONLY), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = { S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI), S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0), /* Linux shouldn't care about secure memory */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64MMFR0_BIGENDEL_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 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_EXACT, ID_AA64MMFR1_LOR_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_HPD_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_VHE_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_VMIDBITS_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64MMFR1_HADBS_SHIFT, 4, 0), ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_LVA_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_IESB_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_LSM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_UAO_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 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), /* RAO */ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_SAFE, 24, 4, 0), /* CWG */ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0), /* ERG */ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 1), /* DminLine */ /* * 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 - AIVIVT. */ ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_EXACT, 14, 2, ICACHE_POLICY_AIVIVT), /* L1Ip */ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0), /* IminLine */ 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_EXACT, 28, 4, 0xf), /* InnerShr */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 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_EXACT, 16, 4, 0), /* TCM */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 12, 4, 0), /* ShareLvl */ S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 8, 4, 0xf), /* OuterShr */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 4, 4, 0), /* PMSA */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 4, 0), /* VMSA */ ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 36, 28, 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_EXACT, 4, 4, 0), /* FPMisc */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 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_isar5[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_ISAR5_RDM_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_ISAR5_CRC32_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_ISAR5_SHA2_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_ISAR5_SHA1_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_ISAR5_AES_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 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_EXACT, 4, 4, 0), /* ac2 */ ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_pfr0[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 12, 4, 0), /* State3 */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 8, 4, 0), /* State2 */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 4, 4, 0), /* State1 */ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, 0, 4, 0), /* State0 */ ARM64_FTR_END, }; static const struct arm64_ftr_bits ftr_id_dfr0[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0), 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, }; /* * 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[0-4], 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_generic_32bits), 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_generic_32bits), 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_generic_32bits), ARM64_FTR_REG(SYS_ID_ISAR5_EL1, ftr_id_isar5), ARM64_FTR_REG(SYS_ID_MMFR4_EL1, ftr_id_mmfr4), /* 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), /* Op1 = 0, CRn = 0, CRm = 4 */ ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0), ARM64_FTR_REG(SYS_ID_AA64PFR1_EL1, ftr_raz), /* 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_raz), /* 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 = 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_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; } 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); 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_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_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_PFR0_EL1, info->reg_id_pfr0); init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1); 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); } } 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; } /* * 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); /* * EL3 is not our concern. * ID_AA64PFR1 is currently RES0. */ 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); /* * If we have AArch32, we care about 32-bit features for compat. * If the system doesn't support AArch32, don't update them. */ if (id_aa64pfr0_32bit_el0(read_system_reg(SYS_ID_AA64PFR0_EL1)) && id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) { 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_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); /* * 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_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_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); } /* * Mismatched CPU features are a recipe for disaster. Don't even * pretend to support them. */ WARN_TAINT_ONCE(taint, TAINT_CPU_OUT_OF_SPEC, "Unsupported CPU feature variation.\n"); } u64 read_system_reg(u32 id) { struct arm64_ftr_reg *regp = get_arm64_ftr_reg(id); /* We shouldn't get a request for an unsupported register */ BUG_ON(!regp); return regp->sys_val; } /* * __raw_read_system_reg() - Used by a STARTING cpu before cpuinfo is populated. * Read the system register on the current CPU */ static u64 __raw_read_system_reg(u32 sys_id) { switch (sys_id) { case SYS_ID_PFR0_EL1: return read_cpuid(ID_PFR0_EL1); case SYS_ID_PFR1_EL1: return read_cpuid(ID_PFR1_EL1); case SYS_ID_DFR0_EL1: return read_cpuid(ID_DFR0_EL1); case SYS_ID_MMFR0_EL1: return read_cpuid(ID_MMFR0_EL1); case SYS_ID_MMFR1_EL1: return read_cpuid(ID_MMFR1_EL1); case SYS_ID_MMFR2_EL1: return read_cpuid(ID_MMFR2_EL1); case SYS_ID_MMFR3_EL1: return read_cpuid(ID_MMFR3_EL1); case SYS_ID_ISAR0_EL1: return read_cpuid(ID_ISAR0_EL1); case SYS_ID_ISAR1_EL1: return read_cpuid(ID_ISAR1_EL1); case SYS_ID_ISAR2_EL1: return read_cpuid(ID_ISAR2_EL1); case SYS_ID_ISAR3_EL1: return read_cpuid(ID_ISAR3_EL1); case SYS_ID_ISAR4_EL1: return read_cpuid(ID_ISAR4_EL1); case SYS_ID_ISAR5_EL1: return read_cpuid(ID_ISAR5_EL1); case SYS_MVFR0_EL1: return read_cpuid(MVFR0_EL1); case SYS_MVFR1_EL1: return read_cpuid(MVFR1_EL1); case SYS_MVFR2_EL1: return read_cpuid(MVFR2_EL1); case SYS_ID_AA64PFR0_EL1: return read_cpuid(ID_AA64PFR0_EL1); case SYS_ID_AA64PFR1_EL1: return read_cpuid(ID_AA64PFR1_EL1); case SYS_ID_AA64DFR0_EL1: return read_cpuid(ID_AA64DFR0_EL1); case SYS_ID_AA64DFR1_EL1: return read_cpuid(ID_AA64DFR1_EL1); case SYS_ID_AA64MMFR0_EL1: return read_cpuid(ID_AA64MMFR0_EL1); case SYS_ID_AA64MMFR1_EL1: return read_cpuid(ID_AA64MMFR1_EL1); case SYS_ID_AA64MMFR2_EL1: return read_cpuid(ID_AA64MMFR2_EL1); case SYS_ID_AA64ISAR0_EL1: return read_cpuid(ID_AA64ISAR0_EL1); case SYS_ID_AA64ISAR1_EL1: return read_cpuid(ID_AA64ISAR1_EL1); case SYS_CNTFRQ_EL0: return read_cpuid(CNTFRQ_EL0); case SYS_CTR_EL0: return read_cpuid(CTR_EL0); case SYS_DCZID_EL0: return read_cpuid(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_system_reg(entry->sys_reg); else val = __raw_read_system_reg(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 runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused) { return is_kernel_in_hyp_mode(); } static bool hyp_offset_low(const struct arm64_cpu_capabilities *entry, int __unused) { phys_addr_t idmap_addr = __pa_symbol(__hyp_idmap_text_start); /* * Activate the lower HYP offset only if: * - the idmap doesn't clash with it, * - the kernel is not running at EL2. */ return idmap_addr > GENMASK(VA_BITS - 2, 0) && !is_kernel_in_hyp_mode(); } static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused) { u64 pfr0 = read_system_reg(SYS_ID_AA64PFR0_EL1); return cpuid_feature_extract_signed_field(pfr0, ID_AA64PFR0_FP_SHIFT) < 0; } static const struct arm64_cpu_capabilities arm64_features[] = { { .desc = "GIC system register CPU interface", .capability = ARM64_HAS_SYSREG_GIC_CPUIF, .def_scope = SCOPE_SYSTEM, .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, .def_scope = SCOPE_SYSTEM, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64MMFR1_EL1, .field_pos = ID_AA64MMFR1_PAN_SHIFT, .sign = FTR_UNSIGNED, .min_field_value = 1, .enable = cpu_enable_pan, }, #endif /* CONFIG_ARM64_PAN */ #if defined(CONFIG_AS_LSE) && defined(CONFIG_ARM64_LSE_ATOMICS) { .desc = "LSE atomic instructions", .capability = ARM64_HAS_LSE_ATOMICS, .def_scope = SCOPE_SYSTEM, .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_AS_LSE && CONFIG_ARM64_LSE_ATOMICS */ { .desc = "Software prefetching using PRFM", .capability = ARM64_HAS_NO_HW_PREFETCH, .def_scope = SCOPE_SYSTEM, .matches = has_no_hw_prefetch, }, #ifdef CONFIG_ARM64_UAO { .desc = "User Access Override", .capability = ARM64_HAS_UAO, .def_scope = SCOPE_SYSTEM, .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, .def_scope = SCOPE_SYSTEM, .matches = cpufeature_pan_not_uao, }, #endif /* CONFIG_ARM64_PAN */ { .desc = "Virtualization Host Extensions", .capability = ARM64_HAS_VIRT_HOST_EXTN, .def_scope = SCOPE_SYSTEM, .matches = runs_at_el2, }, { .desc = "32-bit EL0 Support", .capability = ARM64_HAS_32BIT_EL0, .def_scope = SCOPE_SYSTEM, .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, }, { .desc = "Reduced HYP mapping offset", .capability = ARM64_HYP_OFFSET_LOW, .def_scope = SCOPE_SYSTEM, .matches = hyp_offset_low, }, { /* FP/SIMD is not implemented */ .capability = ARM64_HAS_NO_FPSIMD, .def_scope = SCOPE_SYSTEM, .min_field_value = 0, .matches = has_no_fpsimd, }, {}, }; #define HWCAP_CAP(reg, field, s, min_value, type, cap) \ { \ .desc = #cap, \ .def_scope = SCOPE_SYSTEM, \ .matches = has_cpuid_feature, \ .sys_reg = reg, \ .field_pos = field, \ .sign = s, \ .min_field_value = min_value, \ .hwcap_type = type, \ .hwcap = cap, \ } static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = { HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_PMULL), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_AES), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SHA1), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SHA2), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_CRC32), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_ATOMICS), HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RDM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_ASIMDRDM), HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, HWCAP_FP), HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, HWCAP_FPHP), HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, HWCAP_ASIMD), HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, HWCAP_ASIMDHP), {}, }; static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = { #ifdef CONFIG_COMPAT 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: elf_hwcap |= 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 = (elf_hwcap & cap->hwcap) != 0; 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 */ elf_hwcap |= HWCAP_CPUID; for (; hwcaps->matches; hwcaps++) if (hwcaps->matches(hwcaps, hwcaps->def_scope)) cap_set_elf_hwcap(hwcaps); } void update_cpu_capabilities(const struct arm64_cpu_capabilities *caps, const char *info) { for (; caps->matches; caps++) { if (!caps->matches(caps, caps->def_scope)) continue; if (!cpus_have_cap(caps->capability) && caps->desc) pr_info("%s %s\n", info, caps->desc); cpus_set_cap(caps->capability); } } /* * Run through the enabled capabilities and enable() it on all active * CPUs */ void __init enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps) { for (; caps->matches; caps++) if (caps->enable && cpus_have_cap(caps->capability)) /* * 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. */ stop_machine(caps->enable, NULL, cpu_online_mask); } /* * 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. */ static bool sys_caps_initialised; static inline void set_sys_caps_initialised(void) { sys_caps_initialised = true; } /* * 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_run_el(); verify_cpu_asid_bits(); } 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_local_cpu_features(const struct arm64_cpu_capabilities *caps) { for (; caps->matches; caps++) { if (!cpus_have_cap(caps->capability)) continue; /* * If the new CPU misses an advertised feature, we cannot proceed * further, park the cpu. */ if (!caps->matches(caps, SCOPE_LOCAL_CPU)) { pr_crit("CPU%d: missing feature: %s\n", smp_processor_id(), caps->desc); cpu_die_early(); } if (caps->enable) caps->enable(NULL); } } /* * 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) { verify_local_cpu_errata_workarounds(); verify_local_cpu_features(arm64_features); verify_local_elf_hwcaps(arm64_elf_hwcaps); if (system_supports_32bit_el0()) verify_local_elf_hwcaps(compat_elf_hwcaps); } 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. * Otherwise, this CPU should verify that it has all the system * advertised capabilities. */ if (!sys_caps_initialised) update_cpu_errata_workarounds(); else verify_local_cpu_capabilities(); } static void __init setup_feature_capabilities(void) { update_cpu_capabilities(arm64_features, "detected feature:"); enable_cpu_capabilities(arm64_features); } /* * Check if the current CPU has a given feature capability. * Should be called from non-preemptible context. */ bool this_cpu_has_cap(unsigned int cap) { const struct arm64_cpu_capabilities *caps; if (WARN_ON(preemptible())) return false; for (caps = arm64_features; caps->desc; caps++) if (caps->capability == cap && caps->matches) return caps->matches(caps, SCOPE_LOCAL_CPU); return false; } void __init setup_cpu_features(void) { u32 cwg; int cls; /* Set the CPU feature capabilies */ setup_feature_capabilities(); enable_errata_workarounds(); setup_elf_hwcaps(arm64_elf_hwcaps); if (system_supports_32bit_el0()) setup_elf_hwcaps(compat_elf_hwcaps); /* Advertise that we have computed the system capabilities */ set_sys_caps_initialised(); /* * Check for sane CTR_EL0.CWG value. */ cwg = cache_type_cwg(); cls = cache_line_size(); if (!cwg) pr_warn("No Cache Writeback Granule information, assuming cache line size %d\n", cls); if (L1_CACHE_BYTES < cls) pr_warn("L1_CACHE_BYTES smaller than the Cache Writeback Granule (%d < %d)\n", L1_CACHE_BYTES, cls); } static bool __maybe_unused cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused) { return (cpus_have_const_cap(ARM64_HAS_PAN) && !cpus_have_const_cap(ARM64_HAS_UAO)); } /* * 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; } static int emulate_mrs(struct pt_regs *regs, u32 insn) { int rc; u32 sys_reg, dst; u64 val; /* * 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; rc = emulate_sys_reg(sys_reg, &val); if (!rc) { dst = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RT, insn); regs->user_regs.regs[dst] = val; regs->pc += 4; } return rc; } static struct undef_hook mrs_hook = { .instr_mask = 0xfff00000, .instr_val = 0xd5300000, .pstate_mask = COMPAT_PSR_MODE_MASK, .pstate_val = PSR_MODE_EL0t, .fn = emulate_mrs, }; static int __init enable_mrs_emulation(void) { register_undef_hook(&mrs_hook); return 0; } late_initcall(enable_mrs_emulation);