| /* |
| * Record and handle CPU attributes. |
| * |
| * Copyright (C) 2014 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/>. |
| */ |
| #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 char *icache_policy_str[] = { |
| [0 ... ICACHE_POLICY_PIPT] = "RESERVED/UNKNOWN", |
| [ICACHE_POLICY_VIPT] = "VIPT", |
| [ICACHE_POLICY_PIPT] = "PIPT", |
| [ICACHE_POLICY_VPIPT] = "VPIPT", |
| }; |
| |
| unsigned long __icache_flags; |
| |
| static const char *const hwcap_str[] = { |
| "fp", |
| "asimd", |
| "evtstrm", |
| "aes", |
| "pmull", |
| "sha1", |
| "sha2", |
| "crc32", |
| "atomics", |
| "fphp", |
| "asimdhp", |
| "cpuid", |
| "asimdrdm", |
| "jscvt", |
| "fcma", |
| "lrcpc", |
| "dcpop", |
| "sha3", |
| "sm3", |
| "sm4", |
| "asimddp", |
| "sha512", |
| "sve", |
| "asimdfhm", |
| "dit", |
| "uscat", |
| "ilrcpc", |
| "flagm", |
| "ssbs", |
| "sb", |
| "paca", |
| "pacg", |
| "dcpodp", |
| "sve2", |
| "sveaes", |
| "svepmull", |
| "svebitperm", |
| "svesha3", |
| "svesm4", |
| NULL |
| }; |
| |
| #ifdef CONFIG_COMPAT |
| static const char *const compat_hwcap_str[] = { |
| "swp", |
| "half", |
| "thumb", |
| "26bit", |
| "fastmult", |
| "fpa", |
| "vfp", |
| "edsp", |
| "java", |
| "iwmmxt", |
| "crunch", |
| "thumbee", |
| "neon", |
| "vfpv3", |
| "vfpv3d16", |
| "tls", |
| "vfpv4", |
| "idiva", |
| "idivt", |
| "vfpd32", |
| "lpae", |
| "evtstrm", |
| NULL |
| }; |
| |
| static const char *const compat_hwcap2_str[] = { |
| "aes", |
| "pmull", |
| "sha1", |
| "sha2", |
| "crc32", |
| NULL |
| }; |
| #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; compat_hwcap_str[j]; j++) |
| if (compat_elf_hwcap & (1 << j)) |
| seq_printf(m, " %s", compat_hwcap_str[j]); |
| |
| for (j = 0; compat_hwcap2_str[j]; j++) |
| if (compat_elf_hwcap2 & (1 << j)) |
| seq_printf(m, " %s", compat_hwcap2_str[j]); |
| #endif /* CONFIG_COMPAT */ |
| } else { |
| for (j = 0; hwcap_str[j]; 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; |
| } |
| 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; |
| default: |
| /* Fallthrough */ |
| case ICACHE_POLICY_VIPT: |
| /* Assume aliasing */ |
| set_bit(ICACHEF_ALIASING, &__icache_flags); |
| } |
| |
| 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_E0.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_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_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_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_pfr0 = read_cpuid(ID_PFR0_EL1); |
| info->reg_id_pfr1 = read_cpuid(ID_PFR1_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); |
| } |
| |
| device_initcall(cpuinfo_regs_init); |