summaryrefslogtreecommitdiffstats
path: root/arch/arm64/kernel/cpuinfo.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm64/kernel/cpuinfo.c')
-rw-r--r--arch/arm64/kernel/cpuinfo.c460
1 files changed, 460 insertions, 0 deletions
diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
new file mode 100644
index 000000000..28d4f442b
--- /dev/null
+++ b/arch/arm64/kernel/cpuinfo.c
@@ -0,0 +1,460 @@
+// 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_VPIPT:
+ return "VPIPT";
+ 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_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",
+};
+
+#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);
+CPUREGS_ATTR_RO(smidr_el1, smidr);
+
+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 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_VPIPT:
+ set_bit(ICACHEF_VPIPT, &__icache_flags);
+ 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_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);
+ info->reg_id_aa64smfr0 = read_cpuid(ID_AA64SMFR0_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);
+
+ 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);
+}