From: Keqian Zhu <zhukeqian1@xxxxxxxxxx>
Though we already has a cpu capability named ARM64_HW_DBM, it's a
LOCAL_CPU cap and conditionally compiled by CONFIG_ARM64_HW_AFDBM.
This reports the system wide support of HW_DBM.
Signed-off-by: Keqian Zhu <zhukeqian1@xxxxxxxxxx>
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@xxxxxxxxxx>
---
arch/arm64/include/asm/cpufeature.h | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
index 96e50227f940..edb04e45e030 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -733,6 +733,21 @@ static inline bool system_supports_mixed_endian(void)
return val == 0x1;
}
+static inline bool system_supports_hw_dbm(void)
+{
+ u64 mmfr1;
+ u32 val;
+
+ if (!IS_ENABLED(CONFIG_ARM64_HW_AFDBM))
+ return false;
+
+ mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
+ val = cpuid_feature_extract_unsigned_field(mmfr1,
+ ID_AA64MMFR1_EL1_HAFDBS_SHIFT);
+
+ return val == ID_AA64MMFR1_EL1_HAFDBS_DBM;
+}
+
static __always_inline bool system_supports_fpsimd(void)
{
return !cpus_have_const_cap(ARM64_HAS_NO_FPSIMD);
--
2.34.1
