[PATCH v15 08/16] arm64: cpufeature: add MMFR0 helper functions

AKASHI Takahiro takahiro.akashi at linaro.org
Thu Sep 27 23:48:33 PDT 2018


Those helper functions for MMFR0 register will be used later by kexec_file
loader.

Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: Will Deacon <will.deacon at arm.com>
Reviewed-by: James Morse <james.morse at arm.com>
---
 arch/arm64/include/asm/cpufeature.h | 48 +++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
index 1717ba1db35d..cd90b5252d6d 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -486,11 +486,59 @@ static inline bool system_supports_32bit_el0(void)
 	return cpus_have_const_cap(ARM64_HAS_32BIT_EL0);
 }
 
+static inline bool system_supports_4kb_granule(void)
+{
+	u64 mmfr0;
+	u32 val;
+
+	mmfr0 =	read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
+	val = cpuid_feature_extract_unsigned_field(mmfr0,
+						ID_AA64MMFR0_TGRAN4_SHIFT);
+
+	return val == ID_AA64MMFR0_TGRAN4_SUPPORTED;
+}
+
+static inline bool system_supports_64kb_granule(void)
+{
+	u64 mmfr0;
+	u32 val;
+
+	mmfr0 =	read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
+	val = cpuid_feature_extract_unsigned_field(mmfr0,
+						ID_AA64MMFR0_TGRAN64_SHIFT);
+
+	return val == ID_AA64MMFR0_TGRAN64_SUPPORTED;
+}
+
+static inline bool system_supports_16kb_granule(void)
+{
+	u64 mmfr0;
+	u32 val;
+
+	mmfr0 =	read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
+	val = cpuid_feature_extract_unsigned_field(mmfr0,
+						ID_AA64MMFR0_TGRAN16_SHIFT);
+
+	return val == ID_AA64MMFR0_TGRAN16_SUPPORTED;
+}
+
 static inline bool system_supports_mixed_endian_el0(void)
 {
 	return id_aa64mmfr0_mixed_endian_el0(read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1));
 }
 
+static inline bool system_supports_mixed_endian(void)
+{
+	u64 mmfr0;
+	u32 val;
+
+	mmfr0 =	read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
+	val = cpuid_feature_extract_unsigned_field(mmfr0,
+						ID_AA64MMFR0_BIGENDEL_SHIFT);
+
+	return val == 0x1;
+}
+
 static inline bool system_supports_fpsimd(void)
 {
 	return !cpus_have_const_cap(ARM64_HAS_NO_FPSIMD);
-- 
2.19.0




More information about the linux-arm-kernel mailing list