diff options
Diffstat (limited to '')
| -rw-r--r-- | arch/arm64/kernel/cpufeature.c | 1946 |
1 files changed, 1946 insertions, 0 deletions
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c new file mode 100644 index 000000000..03b0fdcca --- /dev/null +++ b/arch/arm64/kernel/cpufeature.c @@ -0,0 +1,1946 @@ +/* + * 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 <http://www.gnu.org/licenses/>. + */ + +#define pr_fmt(fmt) "CPU features: " fmt + +#include <linux/bsearch.h> +#include <linux/cpumask.h> +#include <linux/percpu.h> +#include <linux/sort.h> +#include <linux/stop_machine.h> +#include <linux/types.h> +#include <linux/mm.h> +#include <linux/cpu.h> + +#include <asm/cpu.h> +#include <asm/cpufeature.h> +#include <asm/cpu_ops.h> +#include <asm/fpsimd.h> +#include <asm/mmu_context.h> +#include <asm/processor.h> +#include <asm/sysreg.h> +#include <asm/traps.h> +#include <asm/vectors.h> +#include <asm/virt.h> + +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_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_PER_CPU_READ_MOSTLY(const char *, this_cpu_vector) = vectors; + +/* + * 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; +} + +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); + + +/* + * 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_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_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, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_DPB_SHIFT, 4, 0), + ARM64_FTR_END, +}; + +static const struct arm64_ftr_bits ftr_id_aa64isar2[] = { + ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64ISAR2_CLEARBHB_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_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_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_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_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_STRICT, 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[] = { + 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_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_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, 4, 4, 0), /* ac2 */ + ARM64_FTR_END, +}; + +static const struct arm64_ftr_bits ftr_id_pfr0[] = { + 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_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_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[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_id_aa64pfr1), + ARM64_FTR_REG(SYS_ID_AA64ZFR0_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_id_aa64isar1), + ARM64_FTR_REG(SYS_ID_AA64ISAR2_EL1, ftr_id_aa64isar2), + + /* 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 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_AA64ISAR2_EL1, info->reg_id_aa64isar2); + 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_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); + } + + if (id_aa64pfr0_sve(info->reg_id_aa64pfr0)) { + init_cpu_ftr_reg(SYS_ZCR_EL1, info->reg_zcr); + sve_init_vq_map(); + } + + /* + * 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; +} + +/* + * 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); + taint |= check_update_ftr_reg(SYS_ID_AA64ISAR2_EL1, cpu, + info->reg_id_aa64isar2, boot->reg_id_aa64isar2); + + /* + * 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 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_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1)) && + id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) { + + taint |= check_update_ftr_reg(SYS_ID_DFR0_EL1, cpu, + 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); + } + + 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)) && + !sys_caps_initialised) + sve_update_vq_map(); + } + + /* + * 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_DFR0_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_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_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_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_ID_AA64ISAR2_EL1); + + read_sysreg_case(SYS_CNTFRQ_EL0); + read_sysreg_case(SYS_CTR_EL0); + read_sysreg_case(SYS_DCZID_EL0); + + default: + BUG(); + return 0; + } +} + +#include <linux/irqchip/arm-gic-v3.h> + +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_cachetype(); + + return ctr & BIT(CTR_IDC_SHIFT); +} + +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 __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_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), + { /* 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 (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && kaslr_offset() > 0) { + 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; + + static bool kpti_applied = false; + int cpu = smp_processor_id(); + + if (__this_cpu_read(this_cpu_vector) == vectors) { + const char *v = arm64_get_bp_hardening_vector(EL1_VECTOR_KPTI); + + __this_cpu_write(this_cpu_vector, v); + } + + if (kpti_applied) + 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) + kpti_applied = 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_ALL_VERSIONS(MIDR_CORTEX_A55), +#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_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 (!alternatives_applied) + 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(CRm_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 << CRm_shift), + .instr_val = 0xd500001f | REG_PSTATE_SSBS_IMM, + .fn = ssbs_emulation_handler, +}; + +static void cpu_enable_ssbs(const struct arm64_cpu_capabilities *__unused) +{ + static bool undef_hook_registered = false; + static DEFINE_SPINLOCK(hook_lock); + + spin_lock(&hook_lock); + if (!undef_hook_registered) { + register_undef_hook(&ssbs_emulation_hook); + undef_hook_registered = true; + } + 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 */ + +static const struct arm64_cpu_capabilities arm64_features[] = { + { + .desc = "GIC system register CPU interface", + .capability = ARM64_HAS_SYSREG_GIC_CPUIF, + .type = ARM64_CPUCAP_SYSTEM_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 */ +#if defined(CONFIG_AS_LSE) && defined(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_AS_LSE && 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, + }, + { + .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, + }, +#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 */ + { + .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, + }, + { + .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 +#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 + {}, +}; + + +#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_CAP_MATCH(match, cap_type, cap) \ + { \ + __HWCAP_CAP(#cap, cap_type, cap) \ + .matches = match, \ + } + +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_SHA2_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_SHA512), + 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_AA64ISAR0_EL1, ID_AA64ISAR0_SHA3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SHA3), + HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SM3), + HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM4_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SM4), + HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_DP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_ASIMDDP), + HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_FHM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_ASIMDFHM), + HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_TS_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_FLAGM), + 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), + HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_DIT_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, HWCAP_DIT), + HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_DCPOP), + HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_JSCVT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_JSCVT), + HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FCMA_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_FCMA), + HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_LRCPC), + HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_ILRCPC), + HWCAP_CAP(SYS_ID_AA64MMFR2_EL1, ID_AA64MMFR2_AT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_USCAT), +#ifdef CONFIG_ARM64_SVE + HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_SVE_SHIFT, FTR_UNSIGNED, ID_AA64PFR0_SVE, CAP_HWCAP, HWCAP_SVE), +#endif + HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_SSBS_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_SSBS_PSTATE_INSNS, CAP_HWCAP, HWCAP_SSBS), + {}, +}; + +#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: + 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, cpucap_default_scope(hwcaps))) + cap_set_elf_hwcap(hwcaps); +} + +/* + * Check if the current CPU has a given feature capability. + * Should be called from non-preemptible context. + */ +static bool __this_cpu_has_cap(const struct arm64_cpu_capabilities *cap_array, + unsigned int cap) +{ + const struct arm64_cpu_capabilities *caps; + + if (WARN_ON(preemptible())) + return false; + + for (caps = cap_array; caps->matches; caps++) + if (caps->capability == cap) + return caps->matches(caps, SCOPE_LOCAL_CPU); + + return false; +} + +static void __update_cpu_capabilities(const struct arm64_cpu_capabilities *caps, + u16 scope_mask, const char *info) +{ + scope_mask &= ARM64_CPUCAP_SCOPE_MASK; + for (; caps->matches; caps++) { + if (!(caps->type & scope_mask) || + !caps->matches(caps, cpucap_default_scope(caps))) + continue; + + if (!cpus_have_cap(caps->capability) && caps->desc) + pr_info("%s %s\n", info, caps->desc); + cpus_set_cap(caps->capability); + } +} + +static void update_cpu_capabilities(u16 scope_mask) +{ + __update_cpu_capabilities(arm64_errata, scope_mask, + "enabling workaround for"); + __update_cpu_capabilities(arm64_features, scope_mask, "detected:"); +} + +static int __enable_cpu_capability(void *arg) +{ + const struct arm64_cpu_capabilities *cap = arg; + + cap->cpu_enable(cap); + return 0; +} + +/* + * Run through the enabled capabilities and enable() it on all active + * CPUs + */ +static void __init +__enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps, + u16 scope_mask) +{ + scope_mask &= ARM64_CPUCAP_SCOPE_MASK; + for (; caps->matches; caps++) { + unsigned int num = caps->capability; + + if (!(caps->type & scope_mask) || !cpus_have_cap(num)) + continue; + + /* Ensure cpus_have_const_cap(num) works */ + static_branch_enable(&cpu_hwcap_keys[num]); + + if (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. + * + * Otherwise, 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 (scope_mask & SCOPE_BOOT_CPU) + caps->cpu_enable(caps); + else + stop_machine(__enable_cpu_capability, + (void *)caps, cpu_online_mask); + } + } +} + +static void __init enable_cpu_capabilities(u16 scope_mask) +{ + __enable_cpu_capabilities(arm64_errata, scope_mask); + __enable_cpu_capabilities(arm64_features, scope_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. + * + * Returns "false" on conflicts. + */ +static bool +__verify_local_cpu_caps(const struct arm64_cpu_capabilities *caps, + u16 scope_mask) +{ + bool cpu_has_cap, system_has_cap; + + scope_mask &= ARM64_CPUCAP_SCOPE_MASK; + + for (; caps->matches; caps++) { + if (!(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 (caps->matches) { + 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); + return false; + } + + return true; +} + +static bool verify_local_cpu_caps(u16 scope_mask) +{ + return __verify_local_cpu_caps(arm64_errata, scope_mask) && + __verify_local_cpu_caps(arm64_features, scope_mask); +} + +/* + * 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(); + /* + * Early features are used by the kernel already. If there + * is a conflict, we cannot proceed further. + */ + if (!verify_local_cpu_caps(SCOPE_BOOT_CPU)) + cpu_panic_kernel(); +} + +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: required vector length(s) missing\n", + smp_processor_id()); + cpu_die_early(); + } + + /* Add checks on other ZCR bits here if necessary */ +} + + +/* + * 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. + */ + if (!verify_local_cpu_caps(SCOPE_ALL & ~SCOPE_BOOT_CPU)) + cpu_die_early(); + + 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(); +} + +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 (!sys_caps_initialised) + 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); +} + +DEFINE_STATIC_KEY_FALSE(arm64_const_caps_ready); +EXPORT_SYMBOL(arm64_const_caps_ready); + +static void __init mark_const_caps_ready(void) +{ + static_branch_enable(&arm64_const_caps_ready); +} + +extern const struct arm64_cpu_capabilities arm64_errata[]; + +bool this_cpu_has_cap(unsigned int cap) +{ + return (__this_cpu_has_cap(arm64_features, cap) || + __this_cpu_has_cap(arm64_errata, cap)); +} + +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(); + mark_const_caps_ready(); + 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 */ + set_sys_caps_initialised(); + + /* + * 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 (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); + pt_regs_write_reg(regs, dst, val); + arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE); + } + + return rc; +} + +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); + +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); +} + +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"); +} |