[PATCH v2 5/8] arm64: cpufeature: Track 32bit EL0 support
From: Suzuki K Poulose
Date: Thu Feb 25 2016 - 04:53:22 EST
Keep track of the support for 32bit EL0.
Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
---
arch/arm64/include/asm/cpufeature.h | 8 +++++++-
arch/arm64/kernel/cpufeature.c | 9 +++++++++
2 files changed, 16 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
index 98f83d7..46c6f4c 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -30,8 +30,9 @@
#define ARM64_HAS_LSE_ATOMICS 5
#define ARM64_WORKAROUND_CAVIUM_23154 6
#define ARM64_WORKAROUND_834220 7
+#define ARM64_HAS_32BIT_EL0 8
-#define ARM64_NCAPS 8
+#define ARM64_NCAPS 9
#ifndef __ASSEMBLY__
@@ -187,6 +188,11 @@ static inline bool cpu_supports_mixed_endian_el0(void)
return id_aa64mmfr0_mixed_endian_el0(read_cpuid(ID_AA64MMFR0_EL1));
}
+static inline bool system_supports_32bit_el0(void)
+{
+ return cpus_have_cap(ARM64_HAS_32BIT_EL0);
+}
+
static inline bool system_supports_mixed_endian_el0(void)
{
return id_aa64mmfr0_mixed_endian_el0(read_system_reg(SYS_ID_AA64MMFR0_EL1));
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 853e575..8f6b674 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -675,6 +675,15 @@ static const struct arm64_cpu_capabilities arm64_features[] = {
.min_field_value = 2,
},
#endif /* CONFIG_AS_LSE && CONFIG_ARM64_LSE_ATOMICS */
+ {
+ .desc = "32 bit EL0",
+ .capability = ARM64_HAS_32BIT_EL0,
+ .matches = has_cpuid_feature,
+ .sys_reg = SYS_ID_AA64PFR0_EL1,
+ .field_pos = ID_AA64PFR0_EL0_SHIFT,
+ .sign = FTR_UNSIGNED,
+ .min_field_value = ID_AA64PFR0_EL0_32BIT_64BIT,
+ },
{},
};
--
1.7.9.5