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Diffstat (limited to 'arch/arm64/kernel/cpuinfo.c')
-rw-r--r--arch/arm64/kernel/cpuinfo.c261
1 files changed, 129 insertions, 132 deletions
diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
index 75d5a867e..212ae6361 100644
--- a/arch/arm64/kernel/cpuinfo.c
+++ b/arch/arm64/kernel/cpuinfo.c
@@ -24,9 +24,13 @@
#include <linux/bug.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
@@ -35,7 +39,6 @@
*/
DEFINE_PER_CPU(struct cpuinfo_arm64, cpu_data);
static struct cpuinfo_arm64 boot_cpu_data;
-static bool mixed_endian_el0 = true;
static char *icache_policy_str[] = {
[ICACHE_POLICY_RESERVED] = "RESERVED/UNKNOWN",
@@ -46,157 +49,152 @@ static char *icache_policy_str[] = {
unsigned long __icache_flags;
-static void cpuinfo_detect_icache_policy(struct cpuinfo_arm64 *info)
+static const char *const hwcap_str[] = {
+ "fp",
+ "asimd",
+ "evtstrm",
+ "aes",
+ "pmull",
+ "sha1",
+ "sha2",
+ "crc32",
+ "atomics",
+ 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"
+};
+
+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)
{
- unsigned int cpu = smp_processor_id();
- u32 l1ip = CTR_L1IP(info->reg_ctr);
+ int i, j;
+
+ for_each_online_cpu(i) {
+ struct cpuinfo_arm64 *cpuinfo = &per_cpu(cpu_data, i);
+ u32 midr = cpuinfo->reg_midr;
- if (l1ip != ICACHE_POLICY_PIPT) {
/*
- * VIPT caches are non-aliasing if the VA always equals the PA
- * in all bit positions that are covered by the index. This is
- * the case if the size of a way (# of sets * line size) does
- * not exceed PAGE_SIZE.
+ * glibc reads /proc/cpuinfo to determine the number of
+ * online processors, looking for lines beginning with
+ * "processor". Give glibc what it expects.
*/
- u32 waysize = icache_get_numsets() * icache_get_linesize();
+ seq_printf(m, "processor\t: %d\n", i);
- if (l1ip != ICACHE_POLICY_VIPT || waysize > PAGE_SIZE)
- set_bit(ICACHEF_ALIASING, &__icache_flags);
+ 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 (personality(current->personality) == PER_LINUX32) {
+#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));
}
- if (l1ip == ICACHE_POLICY_AIVIVT)
- set_bit(ICACHEF_AIVIVT, &__icache_flags);
- pr_info("Detected %s I-cache on CPU%d\n", icache_policy_str[l1ip], cpu);
+ return 0;
}
-bool cpu_supports_mixed_endian_el0(void)
+static void *c_start(struct seq_file *m, loff_t *pos)
{
- return id_aa64mmfr0_mixed_endian_el0(read_cpuid(ID_AA64MMFR0_EL1));
+ return *pos < 1 ? (void *)1 : NULL;
}
-bool system_supports_mixed_endian_el0(void)
+static void *c_next(struct seq_file *m, void *v, loff_t *pos)
{
- return mixed_endian_el0;
+ ++*pos;
+ return NULL;
}
-static void update_mixed_endian_el0_support(struct cpuinfo_arm64 *info)
+static void c_stop(struct seq_file *m, void *v)
{
- mixed_endian_el0 &= id_aa64mmfr0_mixed_endian_el0(info->reg_id_aa64mmfr0);
}
-static void update_cpu_features(struct cpuinfo_arm64 *info)
-{
- update_mixed_endian_el0_support(info);
-}
+const struct seq_operations cpuinfo_op = {
+ .start = c_start,
+ .next = c_next,
+ .stop = c_stop,
+ .show = c_show
+};
-static int check_reg_mask(char *name, u64 mask, u64 boot, u64 cur, int cpu)
+static void cpuinfo_detect_icache_policy(struct cpuinfo_arm64 *info)
{
- if ((boot & mask) == (cur & mask))
- return 0;
-
- pr_warn("SANITY CHECK: Unexpected variation in %s. Boot CPU: %#016lx, CPU%d: %#016lx\n",
- name, (unsigned long)boot, cpu, (unsigned long)cur);
-
- return 1;
-}
+ unsigned int cpu = smp_processor_id();
+ u32 l1ip = CTR_L1IP(info->reg_ctr);
-#define CHECK_MASK(field, mask, boot, cur, cpu) \
- check_reg_mask(#field, mask, (boot)->reg_ ## field, (cur)->reg_ ## field, cpu)
+ if (l1ip != ICACHE_POLICY_PIPT) {
+ /*
+ * VIPT caches are non-aliasing if the VA always equals the PA
+ * in all bit positions that are covered by the index. This is
+ * the case if the size of a way (# of sets * line size) does
+ * not exceed PAGE_SIZE.
+ */
+ u32 waysize = icache_get_numsets() * icache_get_linesize();
-#define CHECK(field, boot, cur, cpu) \
- CHECK_MASK(field, ~0ULL, boot, cur, cpu)
+ if (l1ip != ICACHE_POLICY_VIPT || waysize > PAGE_SIZE)
+ set_bit(ICACHEF_ALIASING, &__icache_flags);
+ }
+ if (l1ip == ICACHE_POLICY_AIVIVT)
+ set_bit(ICACHEF_AIVIVT, &__icache_flags);
-/*
- * Verify that CPUs don't have unexpected differences that will cause problems.
- */
-static void cpuinfo_sanity_check(struct cpuinfo_arm64 *cur)
-{
- unsigned int cpu = smp_processor_id();
- struct cpuinfo_arm64 *boot = &boot_cpu_data;
- unsigned int diff = 0;
-
- /*
- * The kernel can handle differing I-cache policies, but otherwise
- * caches should look identical. Userspace JITs will make use of
- * *minLine.
- */
- diff |= CHECK_MASK(ctr, 0xffff3fff, boot, cur, cpu);
-
- /*
- * Userspace may perform DC ZVA instructions. Mismatched block sizes
- * could result in too much or too little memory being zeroed if a
- * process is preempted and migrated between CPUs.
- */
- diff |= CHECK(dczid, boot, cur, cpu);
-
- /* If different, timekeeping will be broken (especially with KVM) */
- diff |= CHECK(cntfrq, boot, cur, cpu);
-
- /*
- * The kernel uses self-hosted debug features and expects CPUs to
- * support identical debug features. We presently need CTX_CMPs, WRPs,
- * and BRPs to be identical.
- * ID_AA64DFR1 is currently RES0.
- */
- diff |= CHECK(id_aa64dfr0, boot, cur, cpu);
- diff |= CHECK(id_aa64dfr1, boot, cur, cpu);
-
- /*
- * Even in big.LITTLE, processors should be identical instruction-set
- * wise.
- */
- diff |= CHECK(id_aa64isar0, boot, cur, cpu);
- diff |= CHECK(id_aa64isar1, boot, cur, cpu);
-
- /*
- * Differing PARange support is fine as long as all peripherals and
- * memory are mapped within the minimum PARange of all CPUs.
- * Linux should not care about secure memory.
- * ID_AA64MMFR1 is currently RES0.
- */
- diff |= CHECK_MASK(id_aa64mmfr0, 0xffffffffffff0ff0, boot, cur, cpu);
- diff |= CHECK(id_aa64mmfr1, boot, cur, cpu);
-
- /*
- * EL3 is not our concern.
- * ID_AA64PFR1 is currently RES0.
- */
- diff |= CHECK_MASK(id_aa64pfr0, 0xffffffffffff0fff, boot, cur, cpu);
- diff |= CHECK(id_aa64pfr1, boot, cur, cpu);
-
- /*
- * If we have AArch32, we care about 32-bit features for compat. These
- * registers should be RES0 otherwise.
- */
- diff |= CHECK(id_dfr0, boot, cur, cpu);
- diff |= CHECK(id_isar0, boot, cur, cpu);
- diff |= CHECK(id_isar1, boot, cur, cpu);
- diff |= CHECK(id_isar2, boot, cur, cpu);
- diff |= CHECK(id_isar3, boot, cur, cpu);
- diff |= CHECK(id_isar4, boot, cur, cpu);
- diff |= CHECK(id_isar5, boot, cur, cpu);
- /*
- * Regardless of the value of the AuxReg field, the AIFSR, ADFSR, and
- * ACTLR formats could differ across CPUs and therefore would have to
- * be trapped for virtualization anyway.
- */
- diff |= CHECK_MASK(id_mmfr0, 0xff0fffff, boot, cur, cpu);
- diff |= CHECK(id_mmfr1, boot, cur, cpu);
- diff |= CHECK(id_mmfr2, boot, cur, cpu);
- diff |= CHECK(id_mmfr3, boot, cur, cpu);
- diff |= CHECK(id_pfr0, boot, cur, cpu);
- diff |= CHECK(id_pfr1, boot, cur, cpu);
-
- diff |= CHECK(mvfr0, boot, cur, cpu);
- diff |= CHECK(mvfr1, boot, cur, cpu);
- diff |= CHECK(mvfr2, boot, cur, cpu);
-
- /*
- * Mismatched CPU features are a recipe for disaster. Don't even
- * pretend to support them.
- */
- WARN_TAINT_ONCE(diff, TAINT_CPU_OUT_OF_SPEC,
- "Unsupported CPU feature variation.\n");
+ pr_info("Detected %s I-cache on CPU%d\n", icache_policy_str[l1ip], cpu);
}
static void __cpuinfo_store_cpu(struct cpuinfo_arm64 *info)
@@ -236,15 +234,13 @@ static void __cpuinfo_store_cpu(struct cpuinfo_arm64 *info)
cpuinfo_detect_icache_policy(info);
check_local_cpu_errata();
- check_local_cpu_features();
- update_cpu_features(info);
}
void cpuinfo_store_cpu(void)
{
struct cpuinfo_arm64 *info = this_cpu_ptr(&cpu_data);
__cpuinfo_store_cpu(info);
- cpuinfo_sanity_check(info);
+ update_cpu_features(smp_processor_id(), info, &boot_cpu_data);
}
void __init cpuinfo_store_boot_cpu(void)
@@ -253,4 +249,5 @@ void __init cpuinfo_store_boot_cpu(void)
__cpuinfo_store_cpu(info);
boot_cpu_data = *info;
+ init_cpu_features(&boot_cpu_data);
}