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Diffstat (limited to 'arch/arm64/kernel/cpufeature.c')
-rw-r--r--arch/arm64/kernel/cpufeature.c53
1 files changed, 46 insertions, 7 deletions
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 5ad86ceac..3c9aed32f 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -21,24 +21,57 @@
#include <linux/types.h>
#include <asm/cpu.h>
#include <asm/cpufeature.h>
+#include <asm/processor.h>
static bool
-has_id_aa64pfr0_feature(const struct arm64_cpu_capabilities *entry)
+feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
{
- u64 val;
+ int val = cpuid_feature_extract_field(reg, entry->field_pos);
- val = read_cpuid(id_aa64pfr0_el1);
- return (val & entry->register_mask) == entry->register_value;
+ return val >= entry->min_field_value;
}
+#define __ID_FEAT_CHK(reg) \
+static bool __maybe_unused \
+has_##reg##_feature(const struct arm64_cpu_capabilities *entry) \
+{ \
+ u64 val; \
+ \
+ val = read_cpuid(reg##_el1); \
+ return feature_matches(val, entry); \
+}
+
+__ID_FEAT_CHK(id_aa64pfr0);
+__ID_FEAT_CHK(id_aa64mmfr1);
+__ID_FEAT_CHK(id_aa64isar0);
+
static const struct arm64_cpu_capabilities arm64_features[] = {
{
.desc = "GIC system register CPU interface",
.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
.matches = has_id_aa64pfr0_feature,
- .register_mask = (0xf << 24),
- .register_value = (1 << 24),
+ .field_pos = 24,
+ .min_field_value = 1,
+ },
+#ifdef CONFIG_ARM64_PAN
+ {
+ .desc = "Privileged Access Never",
+ .capability = ARM64_HAS_PAN,
+ .matches = has_id_aa64mmfr1_feature,
+ .field_pos = 20,
+ .min_field_value = 1,
+ .enable = cpu_enable_pan,
},
+#endif /* CONFIG_ARM64_PAN */
+#if defined(CONFIG_AS_LSE) && defined(CONFIG_ARM64_LSE_ATOMICS)
+ {
+ .desc = "LSE atomic instructions",
+ .capability = ARM64_HAS_LSE_ATOMICS,
+ .matches = has_id_aa64isar0_feature,
+ .field_pos = 20,
+ .min_field_value = 2,
+ },
+#endif /* CONFIG_AS_LSE && CONFIG_ARM64_LSE_ATOMICS */
{},
};
@@ -55,9 +88,15 @@ void check_cpu_capabilities(const struct arm64_cpu_capabilities *caps,
pr_info("%s %s\n", info, caps[i].desc);
cpus_set_cap(caps[i].capability);
}
+
+ /* second pass allows enable() to consider interacting capabilities */
+ for (i = 0; caps[i].desc; i++) {
+ if (cpus_have_cap(caps[i].capability) && caps[i].enable)
+ caps[i].enable();
+ }
}
void check_local_cpu_features(void)
{
- check_cpu_capabilities(arm64_features, "detected feature");
+ check_cpu_capabilities(arm64_features, "detected feature:");
}