1 files changed, 129 insertions, 132 deletions

diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
index 75d5a867e7fb..212ae6361d8b 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);
 }