// SPDX-License-Identifier: GPL-2.0-only /* * Record and handle CPU attributes. * * Copyright (C) 2014 ARM Ltd. */ #include <asm/arch_timer.h> #include <asm/cache.h> #include <asm/cpu.h> #include <asm/cputype.h> #include <asm/cpufeature.h> #include <asm/fpsimd.h> #include <linux/bitops.h> #include <linux/bug.h> #include <linux/compat.h> #include <linux/elf.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/personality.h> #include <linux/preempt.h> #include <linux/printk.h> #include <linux/seq_file.h> #include <linux/sched.h> #include <linux/smp.h> #include <linux/delay.h> /* * In case the boot CPU is hotpluggable, we record its initial state and * current state separately. Certain system registers may contain different * values depending on configuration at or after reset. */ DEFINE_PER_CPU(struct cpuinfo_arm64, cpu_data); static struct cpuinfo_arm64 boot_cpu_data; static const char *icache_policy_str[] = { [ICACHE_POLICY_VPIPT] = "VPIPT", [ICACHE_POLICY_RESERVED] = "RESERVED/UNKNOWN", [ICACHE_POLICY_VIPT] = "VIPT", [ICACHE_POLICY_PIPT] = "PIPT", }; unsigned long __icache_flags; static const char *const hwcap_str[] = { [KERNEL_HWCAP_FP] = "fp", [KERNEL_HWCAP_ASIMD] = "asimd", [KERNEL_HWCAP_EVTSTRM] = "evtstrm", [KERNEL_HWCAP_AES] = "aes", [KERNEL_HWCAP_PMULL] = "pmull", [KERNEL_HWCAP_SHA1] = "sha1", [KERNEL_HWCAP_SHA2] = "sha2", [KERNEL_HWCAP_CRC32] = "crc32", [KERNEL_HWCAP_ATOMICS] = "atomics", [KERNEL_HWCAP_FPHP] = "fphp", [KERNEL_HWCAP_ASIMDHP] = "asimdhp", [KERNEL_HWCAP_CPUID] = "cpuid", [KERNEL_HWCAP_ASIMDRDM] = "asimdrdm", [KERNEL_HWCAP_JSCVT] = "jscvt", [KERNEL_HWCAP_FCMA] = "fcma", [KERNEL_HWCAP_LRCPC] = "lrcpc", [KERNEL_HWCAP_DCPOP] = "dcpop", [KERNEL_HWCAP_SHA3] = "sha3", [KERNEL_HWCAP_SM3] = "sm3", [KERNEL_HWCAP_SM4] = "sm4", [KERNEL_HWCAP_ASIMDDP] = "asimddp", [KERNEL_HWCAP_SHA512] = "sha512", [KERNEL_HWCAP_SVE] = "sve", [KERNEL_HWCAP_ASIMDFHM] = "asimdfhm", [KERNEL_HWCAP_DIT] = "dit", [KERNEL_HWCAP_USCAT] = "uscat", [KERNEL_HWCAP_ILRCPC] = "ilrcpc", [KERNEL_HWCAP_FLAGM] = "flagm", [KERNEL_HWCAP_SSBS] = "ssbs", [KERNEL_HWCAP_SB] = "sb", [KERNEL_HWCAP_PACA] = "paca", [KERNEL_HWCAP_PACG] = "pacg", [KERNEL_HWCAP_DCPODP] = "dcpodp", [KERNEL_HWCAP_SVE2] = "sve2", [KERNEL_HWCAP_SVEAES] = "sveaes", [KERNEL_HWCAP_SVEPMULL] = "svepmull", [KERNEL_HWCAP_SVEBITPERM] = "svebitperm", [KERNEL_HWCAP_SVESHA3] = "svesha3", [KERNEL_HWCAP_SVESM4] = "svesm4", [KERNEL_HWCAP_FLAGM2] = "flagm2", [KERNEL_HWCAP_FRINT] = "frint", [KERNEL_HWCAP_SVEI8MM] = "svei8mm", [KERNEL_HWCAP_SVEF32MM] = "svef32mm", [KERNEL_HWCAP_SVEF64MM] = "svef64mm", [KERNEL_HWCAP_SVEBF16] = "svebf16", [KERNEL_HWCAP_I8MM] = "i8mm", [KERNEL_HWCAP_BF16] = "bf16", [KERNEL_HWCAP_DGH] = "dgh", [KERNEL_HWCAP_RNG] = "rng", [KERNEL_HWCAP_BTI] = "bti", [KERNEL_HWCAP_MTE] = "mte", }; #ifdef CONFIG_COMPAT #define COMPAT_KERNEL_HWCAP(x) const_ilog2(COMPAT_HWCAP_ ## x) static const char *const compat_hwcap_str[] = { [COMPAT_KERNEL_HWCAP(SWP)] = "swp", [COMPAT_KERNEL_HWCAP(HALF)] = "half", [COMPAT_KERNEL_HWCAP(THUMB)] = "thumb", [COMPAT_KERNEL_HWCAP(26BIT)] = NULL, /* Not possible on arm64 */ [COMPAT_KERNEL_HWCAP(FAST_MULT)] = "fastmult", [COMPAT_KERNEL_HWCAP(FPA)] = NULL, /* Not possible on arm64 */ [COMPAT_KERNEL_HWCAP(VFP)] = "vfp", [COMPAT_KERNEL_HWCAP(EDSP)] = "edsp", [COMPAT_KERNEL_HWCAP(JAVA)] = NULL, /* Not possible on arm64 */ [COMPAT_KERNEL_HWCAP(IWMMXT)] = NULL, /* Not possible on arm64 */ [COMPAT_KERNEL_HWCAP(CRUNCH)] = NULL, /* Not possible on arm64 */ [COMPAT_KERNEL_HWCAP(THUMBEE)] = NULL, /* Not possible on arm64 */ [COMPAT_KERNEL_HWCAP(NEON)] = "neon", [COMPAT_KERNEL_HWCAP(VFPv3)] = "vfpv3", [COMPAT_KERNEL_HWCAP(VFPV3D16)] = NULL, /* Not possible on arm64 */ [COMPAT_KERNEL_HWCAP(TLS)] = "tls", [COMPAT_KERNEL_HWCAP(VFPv4)] = "vfpv4", [COMPAT_KERNEL_HWCAP(IDIVA)] = "idiva", [COMPAT_KERNEL_HWCAP(IDIVT)] = "idivt", [COMPAT_KERNEL_HWCAP(VFPD32)] = NULL, /* Not possible on arm64 */ [COMPAT_KERNEL_HWCAP(LPAE)] = "lpae", [COMPAT_KERNEL_HWCAP(EVTSTRM)] = "evtstrm", }; #define COMPAT_KERNEL_HWCAP2(x) const_ilog2(COMPAT_HWCAP2_ ## x) static const char *const compat_hwcap2_str[] = { [COMPAT_KERNEL_HWCAP2(AES)] = "aes", [COMPAT_KERNEL_HWCAP2(PMULL)] = "pmull", [COMPAT_KERNEL_HWCAP2(SHA1)] = "sha1", [COMPAT_KERNEL_HWCAP2(SHA2)] = "sha2", [COMPAT_KERNEL_HWCAP2(CRC32)] = "crc32", }; #endif /* CONFIG_COMPAT */ static int c_show(struct seq_file *m, void *v) { int i, j; bool compat = personality(current->personality) == PER_LINUX32; for_each_online_cpu(i) { struct cpuinfo_arm64 *cpuinfo = &per_cpu(cpu_data, i); u32 midr = cpuinfo->reg_midr; /* * glibc reads /proc/cpuinfo to determine the number of * online processors, looking for lines beginning with * "processor". Give glibc what it expects. */ seq_printf(m, "processor\t: %d\n", i); if (compat) seq_printf(m, "model name\t: ARMv8 Processor rev %d (%s)\n", MIDR_REVISION(midr), COMPAT_ELF_PLATFORM); seq_printf(m, "BogoMIPS\t: %lu.%02lu\n", loops_per_jiffy / (500000UL/HZ), loops_per_jiffy / (5000UL/HZ) % 100); /* * Dump out the common processor features in a single line. * Userspace should read the hwcaps with getauxval(AT_HWCAP) * rather than attempting to parse this, but there's a body of * software which does already (at least for 32-bit). */ seq_puts(m, "Features\t:"); if (compat) { #ifdef CONFIG_COMPAT for (j = 0; j < ARRAY_SIZE(compat_hwcap_str); j++) { if (compat_elf_hwcap & (1 << j)) { /* * Warn once if any feature should not * have been present on arm64 platform. */ if (WARN_ON_ONCE(!compat_hwcap_str[j])) continue; seq_printf(m, " %s", compat_hwcap_str[j]); } } for (j = 0; j < ARRAY_SIZE(compat_hwcap2_str); j++) if (compat_elf_hwcap2 & (1 << j)) seq_printf(m, " %s", compat_hwcap2_str[j]); #endif /* CONFIG_COMPAT */ } else { for (j = 0; j < ARRAY_SIZE(hwcap_str); j++) if (cpu_have_feature(j)) seq_printf(m, " %s", hwcap_str[j]); } seq_puts(m, "\n"); seq_printf(m, "CPU implementer\t: 0x%02x\n", MIDR_IMPLEMENTOR(midr)); seq_printf(m, "CPU architecture: 8\n"); seq_printf(m, "CPU variant\t: 0x%x\n", MIDR_VARIANT(midr)); seq_printf(m, "CPU part\t: 0x%03x\n", MIDR_PARTNUM(midr)); seq_printf(m, "CPU revision\t: %d\n\n", MIDR_REVISION(midr)); } return 0; } static void *c_start(struct seq_file *m, loff_t *pos) { return *pos < 1 ? (void *)1 : NULL; } static void *c_next(struct seq_file *m, void *v, loff_t *pos) { ++*pos; return NULL; } static void c_stop(struct seq_file *m, void *v) { } const struct seq_operations cpuinfo_op = { .start = c_start, .next = c_next, .stop = c_stop, .show = c_show }; static struct kobj_type cpuregs_kobj_type = { .sysfs_ops = &kobj_sysfs_ops, }; /* * The ARM ARM uses the phrase "32-bit register" to describe a register * whose upper 32 bits are RES0 (per C5.1.1, ARM DDI 0487A.i), however * no statement is made as to whether the upper 32 bits will or will not * be made use of in future, and between ARM DDI 0487A.c and ARM DDI * 0487A.d CLIDR_EL1 was expanded from 32-bit to 64-bit. * * Thus, while both MIDR_EL1 and REVIDR_EL1 are described as 32-bit * registers, we expose them both as 64 bit values to cater for possible * future expansion without an ABI break. */ #define kobj_to_cpuinfo(kobj) container_of(kobj, struct cpuinfo_arm64, kobj) #define CPUREGS_ATTR_RO(_name, _field) \ static ssize_t _name##_show(struct kobject *kobj, \ struct kobj_attribute *attr, char *buf) \ { \ struct cpuinfo_arm64 *info = kobj_to_cpuinfo(kobj); \ \ if (info->reg_midr) \ return sprintf(buf, "0x%016llx\n", info->reg_##_field); \ else \ return 0; \ } \ static struct kobj_attribute cpuregs_attr_##_name = __ATTR_RO(_name) CPUREGS_ATTR_RO(midr_el1, midr); CPUREGS_ATTR_RO(revidr_el1, revidr); static struct attribute *cpuregs_id_attrs[] = { &cpuregs_attr_midr_el1.attr, &cpuregs_attr_revidr_el1.attr, NULL }; static const struct attribute_group cpuregs_attr_group = { .attrs = cpuregs_id_attrs, .name = "identification" }; static int cpuid_cpu_online(unsigned int cpu) { int rc; struct device *dev; struct cpuinfo_arm64 *info = &per_cpu(cpu_data, cpu); dev = get_cpu_device(cpu); if (!dev) { rc = -ENODEV; goto out; } rc = kobject_add(&info->kobj, &dev->kobj, "regs"); if (rc) goto out; rc = sysfs_create_group(&info->kobj, &cpuregs_attr_group); if (rc) kobject_del(&info->kobj); out: return rc; } static int cpuid_cpu_offline(unsigned int cpu) { struct device *dev; struct cpuinfo_arm64 *info = &per_cpu(cpu_data, cpu); dev = get_cpu_device(cpu); if (!dev) return -ENODEV; if (info->kobj.parent) { sysfs_remove_group(&info->kobj, &cpuregs_attr_group); kobject_del(&info->kobj); } return 0; } static int __init cpuinfo_regs_init(void) { int cpu, ret; for_each_possible_cpu(cpu) { struct cpuinfo_arm64 *info = &per_cpu(cpu_data, cpu); kobject_init(&info->kobj, &cpuregs_kobj_type); } ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "arm64/cpuinfo:online", cpuid_cpu_online, cpuid_cpu_offline); if (ret < 0) { pr_err("cpuinfo: failed to register hotplug callbacks.\n"); return ret; } return 0; } device_initcall(cpuinfo_regs_init); static void cpuinfo_detect_icache_policy(struct cpuinfo_arm64 *info) { unsigned int cpu = smp_processor_id(); u32 l1ip = CTR_L1IP(info->reg_ctr); switch (l1ip) { case ICACHE_POLICY_PIPT: break; case ICACHE_POLICY_VPIPT: set_bit(ICACHEF_VPIPT, &__icache_flags); break; case ICACHE_POLICY_RESERVED: case ICACHE_POLICY_VIPT: /* Assume aliasing */ set_bit(ICACHEF_ALIASING, &__icache_flags); break; } pr_info("Detected %s I-cache on CPU%d\n", icache_policy_str[l1ip], cpu); } static void __cpuinfo_store_cpu_32bit(struct cpuinfo_32bit *info) { info->reg_id_dfr0 = read_cpuid(ID_DFR0_EL1); info->reg_id_dfr1 = read_cpuid(ID_DFR1_EL1); info->reg_id_isar0 = read_cpuid(ID_ISAR0_EL1); info->reg_id_isar1 = read_cpuid(ID_ISAR1_EL1); info->reg_id_isar2 = read_cpuid(ID_ISAR2_EL1); info->reg_id_isar3 = read_cpuid(ID_ISAR3_EL1); info->reg_id_isar4 = read_cpuid(ID_ISAR4_EL1); info->reg_id_isar5 = read_cpuid(ID_ISAR5_EL1); info->reg_id_isar6 = read_cpuid(ID_ISAR6_EL1); info->reg_id_mmfr0 = read_cpuid(ID_MMFR0_EL1); info->reg_id_mmfr1 = read_cpuid(ID_MMFR1_EL1); info->reg_id_mmfr2 = read_cpuid(ID_MMFR2_EL1); info->reg_id_mmfr3 = read_cpuid(ID_MMFR3_EL1); info->reg_id_mmfr4 = read_cpuid(ID_MMFR4_EL1); info->reg_id_mmfr5 = read_cpuid(ID_MMFR5_EL1); info->reg_id_pfr0 = read_cpuid(ID_PFR0_EL1); info->reg_id_pfr1 = read_cpuid(ID_PFR1_EL1); info->reg_id_pfr2 = read_cpuid(ID_PFR2_EL1); info->reg_mvfr0 = read_cpuid(MVFR0_EL1); info->reg_mvfr1 = read_cpuid(MVFR1_EL1); info->reg_mvfr2 = read_cpuid(MVFR2_EL1); } static void __cpuinfo_store_cpu(struct cpuinfo_arm64 *info) { info->reg_cntfrq = arch_timer_get_cntfrq(); /* * Use the effective value of the CTR_EL0 than the raw value * exposed by the CPU. CTR_EL0.IDC field value must be interpreted * with the CLIDR_EL1 fields to avoid triggering false warnings * when there is a mismatch across the CPUs. Keep track of the * effective value of the CTR_EL0 in our internal records for * accurate sanity check and feature enablement. */ info->reg_ctr = read_cpuid_effective_cachetype(); info->reg_dczid = read_cpuid(DCZID_EL0); info->reg_midr = read_cpuid_id(); info->reg_revidr = read_cpuid(REVIDR_EL1); info->reg_id_aa64dfr0 = read_cpuid(ID_AA64DFR0_EL1); info->reg_id_aa64dfr1 = read_cpuid(ID_AA64DFR1_EL1); info->reg_id_aa64isar0 = read_cpuid(ID_AA64ISAR0_EL1); info->reg_id_aa64isar1 = read_cpuid(ID_AA64ISAR1_EL1); info->reg_id_aa64mmfr0 = read_cpuid(ID_AA64MMFR0_EL1); info->reg_id_aa64mmfr1 = read_cpuid(ID_AA64MMFR1_EL1); info->reg_id_aa64mmfr2 = read_cpuid(ID_AA64MMFR2_EL1); info->reg_id_aa64pfr0 = read_cpuid(ID_AA64PFR0_EL1); info->reg_id_aa64pfr1 = read_cpuid(ID_AA64PFR1_EL1); info->reg_id_aa64zfr0 = read_cpuid(ID_AA64ZFR0_EL1); if (id_aa64pfr1_mte(info->reg_id_aa64pfr1)) info->reg_gmid = read_cpuid(GMID_EL1); if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) __cpuinfo_store_cpu_32bit(&info->aarch32); if (IS_ENABLED(CONFIG_ARM64_SVE) && id_aa64pfr0_sve(info->reg_id_aa64pfr0)) info->reg_zcr = read_zcr_features(); cpuinfo_detect_icache_policy(info); } void cpuinfo_store_cpu(void) { struct cpuinfo_arm64 *info = this_cpu_ptr(&cpu_data); __cpuinfo_store_cpu(info); update_cpu_features(smp_processor_id(), info, &boot_cpu_data); } void __init cpuinfo_store_boot_cpu(void) { struct cpuinfo_arm64 *info = &per_cpu(cpu_data, 0); __cpuinfo_store_cpu(info); boot_cpu_data = *info; init_cpu_features(&boot_cpu_data); }