summaryrefslogtreecommitdiffstats
path: root/arch/arm64/kernel/cpuinfo.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/arm64/kernel/cpuinfo.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arm64/kernel/cpuinfo.c')
-rw-r--r--arch/arm64/kernel/cpuinfo.c389
1 files changed, 389 insertions, 0 deletions
diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
new file mode 100644
index 000000000..36bd58d8c
--- /dev/null
+++ b/arch/arm64/kernel/cpuinfo.c
@@ -0,0 +1,389 @@
+/*
+ * 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",
+ 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 (elf_hwcap & (1 << 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();
+ info->reg_ctr = read_cpuid_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_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);