diff options
Diffstat (limited to 'arch/arm64/kernel/cpuinfo.c')
| -rw-r--r-- | arch/arm64/kernel/cpuinfo.c | 425 |
1 files changed, 425 insertions, 0 deletions
diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c new file mode 100644 index 000000000..4c0e72781 --- /dev/null +++ b/arch/arm64/kernel/cpuinfo.c @@ -0,0 +1,425 @@ +// 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", + [KERNEL_HWCAP_ECV] = "ecv", + [KERNEL_HWCAP_AFP] = "afp", + [KERNEL_HWCAP_RPRES] = "rpres", +}; + +#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%016x\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(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 + * acurate 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_aa64isar2 = read_cpuid(ID_AA64ISAR2_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); + + /* Update the 32bit ID registers only if AArch32 is implemented */ + if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) { + 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); + } + + 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); +} |