Quelle  cpuinfo.c   Sprache: C

// 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 inline const char *icache_policy_str(int l1ip)
{
 switch (l1ip) {
 case CTR_EL0_L1Ip_VIPT:
  return "VIPT";
 case CTR_EL0_L1Ip_PIPT:
  return "PIPT";
 default:
  return "RESERVED/UNKNOWN";
 }
}

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_GCS]  = "gcs",
 [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",
 [KERNEL_HWCAP_MTE3]  = "mte3",
 [KERNEL_HWCAP_SME]  = "sme",
 [KERNEL_HWCAP_SME_I16I64] = "smei16i64",
 [KERNEL_HWCAP_SME_F64F64] = "smef64f64",
 [KERNEL_HWCAP_SME_I8I32] = "smei8i32",
 [KERNEL_HWCAP_SME_F16F32] = "smef16f32",
 [KERNEL_HWCAP_SME_B16F32] = "smeb16f32",
 [KERNEL_HWCAP_SME_F32F32] = "smef32f32",
 [KERNEL_HWCAP_SME_FA64]  = "smefa64",
 [KERNEL_HWCAP_WFXT]  = "wfxt",
 [KERNEL_HWCAP_EBF16]  = "ebf16",
 [KERNEL_HWCAP_SVE_EBF16] = "sveebf16",
 [KERNEL_HWCAP_CSSC]  = "cssc",
 [KERNEL_HWCAP_RPRFM]  = "rprfm",
 [KERNEL_HWCAP_SVE2P1]  = "sve2p1",
 [KERNEL_HWCAP_SME2]  = "sme2",
 [KERNEL_HWCAP_SME2P1]  = "sme2p1",
 [KERNEL_HWCAP_SME_I16I32] = "smei16i32",
 [KERNEL_HWCAP_SME_BI32I32] = "smebi32i32",
 [KERNEL_HWCAP_SME_B16B16] = "smeb16b16",
 [KERNEL_HWCAP_SME_F16F16] = "smef16f16",
 [KERNEL_HWCAP_MOPS]  = "mops",
 [KERNEL_HWCAP_HBC]  = "hbc",
 [KERNEL_HWCAP_SVE_B16B16] = "sveb16b16",
 [KERNEL_HWCAP_LRCPC3]  = "lrcpc3",
 [KERNEL_HWCAP_LSE128]  = "lse128",
 [KERNEL_HWCAP_FPMR]  = "fpmr",
 [KERNEL_HWCAP_LUT]  = "lut",
 [KERNEL_HWCAP_FAMINMAX]  = "faminmax",
 [KERNEL_HWCAP_F8CVT]  = "f8cvt",
 [KERNEL_HWCAP_F8FMA]  = "f8fma",
 [KERNEL_HWCAP_F8DP4]  = "f8dp4",
 [KERNEL_HWCAP_F8DP2]  = "f8dp2",
 [KERNEL_HWCAP_F8E4M3]  = "f8e4m3",
 [KERNEL_HWCAP_F8E5M2]  = "f8e5m2",
 [KERNEL_HWCAP_SME_LUTV2] = "smelutv2",
 [KERNEL_HWCAP_SME_F8F16] = "smef8f16",
 [KERNEL_HWCAP_SME_F8F32] = "smef8f32",
 [KERNEL_HWCAP_SME_SF8FMA] = "smesf8fma",
 [KERNEL_HWCAP_SME_SF8DP4] = "smesf8dp4",
 [KERNEL_HWCAP_SME_SF8DP2] = "smesf8dp2",
 [KERNEL_HWCAP_POE]  = "poe",
 [KERNEL_HWCAP_CMPBR]  = "cmpbr",
 [KERNEL_HWCAP_FPRCVT]  = "fprcvt",
 [KERNEL_HWCAP_F8MM8]  = "f8mm8",
 [KERNEL_HWCAP_F8MM4]  = "f8mm4",
 [KERNEL_HWCAP_SVE_F16MM] = "svef16mm",
 [KERNEL_HWCAP_SVE_ELTPERM] = "sveeltperm",
 [KERNEL_HWCAP_SVE_AES2]  = "sveaes2",
 [KERNEL_HWCAP_SVE_BFSCALE] = "svebfscale",
 [KERNEL_HWCAP_SVE2P2]  = "sve2p2",
 [KERNEL_HWCAP_SME2P2]  = "sme2p2",
 [KERNEL_HWCAP_SME_SBITPERM] = "smesbitperm",
 [KERNEL_HWCAP_SME_AES]  = "smeaes",
 [KERNEL_HWCAP_SME_SFEXPA] = "smesfexpa",
 [KERNEL_HWCAP_SME_STMOP] = "smestmop",
 [KERNEL_HWCAP_SME_SMOP4] = "smesmop4",
 [KERNEL_HWCAP_MTE_FAR]  = "mtefar",
 [KERNEL_HWCAP_MTE_STORE_ONLY] = "mtestoreonly",
};

#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",
 [COMPAT_KERNEL_HWCAP(FPHP)] = "fphp",
 [COMPAT_KERNEL_HWCAP(ASIMDHP)] = "asimdhp",
 [COMPAT_KERNEL_HWCAP(ASIMDDP)] = "asimddp",
 [COMPAT_KERNEL_HWCAP(ASIMDFHM)] = "asimdfhm",
 [COMPAT_KERNEL_HWCAP(ASIMDBF16)] = "asimdbf16",
 [COMPAT_KERNEL_HWCAP(I8MM)] = "i8mm",
};

#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",
 [COMPAT_KERNEL_HWCAP2(SB)] = "sb",
 [COMPAT_KERNEL_HWCAP2(SSBS)] = "ssbs",
};
#endif /* CONFIG_COMPAT */

static int c_show(struct seq_file *m, void *v)
{
 int j;
 int cpu = m->index;
 bool compat = personality(current->personality) == PER_LINUX32;
 struct cpuinfo_arm64 *cpuinfo = v;
 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", cpu);
 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_puts(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)
{
 *pos = cpumask_next(*pos - 1, cpu_online_mask);
 return *pos < nr_cpu_ids ? &per_cpu(cpu_data, *pos) : NULL;
}

static void *c_next(struct seq_file *m, void *v, loff_t *pos)
{
 ++*pos;
 return c_start(m, pos);
}

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 const 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);
CPUREGS_ATTR_RO(aidr_el1, aidr);
CPUREGS_ATTR_RO(smidr_el1, smidr);

static struct attribute *cpuregs_id_attrs[] = {
 &cpuregs_attr_midr_el1.attr,
 &cpuregs_attr_revidr_el1.attr,
 &cpuregs_attr_aidr_el1.attr,
 NULL
};

static const struct attribute_group cpuregs_attr_group = {
 .attrs = cpuregs_id_attrs,
 .name = "identification"
};

static struct attribute *sme_cpuregs_id_attrs[] = {
 &cpuregs_attr_smidr_el1.attr,
 NULL
};

static const struct attribute_group sme_cpuregs_attr_group = {
 .attrs = sme_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);
 if (system_supports_sme())
  rc = sysfs_merge_group(&info->kobj, &sme_cpuregs_attr_group);
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 CTR_EL0_L1Ip_PIPT:
  break;
 case CTR_EL0_L1Ip_VIPT:
 default:
  /* 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_aidr = read_cpuid(AIDR_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_aa64isar3 = read_cpuid(ID_AA64ISAR3_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_aa64mmfr3 = read_cpuid(ID_AA64MMFR3_EL1);
 info->reg_id_aa64mmfr4 = read_cpuid(ID_AA64MMFR4_EL1);
 info->reg_id_aa64pfr0 = read_cpuid(ID_AA64PFR0_EL1);
 info->reg_id_aa64pfr1 = read_cpuid(ID_AA64PFR1_EL1);
 info->reg_id_aa64pfr2 = read_cpuid(ID_AA64PFR2_EL1);
 info->reg_id_aa64zfr0 = read_cpuid(ID_AA64ZFR0_EL1);
 info->reg_id_aa64smfr0 = read_cpuid(ID_AA64SMFR0_EL1);
 info->reg_id_aa64fpfr0 = read_cpuid(ID_AA64FPFR0_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);

 /*
 * info->reg_mpamidr deferred to {init,update}_cpu_features because we
 * don't want to read it (and trigger a trap on buggy firmware) if
 * using an aa64pfr0_el1 override to unconditionally disable MPAM.
 */

 if (IS_ENABLED(CONFIG_ARM64_SME) &&
     id_aa64pfr1_sme(info->reg_id_aa64pfr1)) {
  /*
 * We mask out SMPS since even if the hardware
 * supports priorities the kernel does not at present
 * and we block access to them.
 */
  info->reg_smidr = read_cpuid(SMIDR_EL1) & ~SMIDR_EL1_SMPS;
 }

 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);
}