arm64/hwcap: Support FEAT_EBF16
The v9.2 feature FEAT_EBF16 provides support for an extended BFloat16 mode.
Allow userspace to discover system support for this feature by adding a
hwcap for it.
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/Documentation/arm64/elf_hwcaps.rst b/Documentation/arm64/elf_hwcaps.rst
index 3d116fb..31fc10b 100644
--- a/Documentation/arm64/elf_hwcaps.rst
+++ b/Documentation/arm64/elf_hwcaps.rst
@@ -301,6 +301,10 @@
Functionality implied by ID_AA64ISAR2_EL1.WFXT == 0b0010.
+HWCAP2_EBF16
+
+ Functionality implied by ID_AA64ISAR1_EL1.BF16 == 0b0010.
+
4. Unused AT_HWCAP bits
-----------------------
diff --git a/arch/arm64/include/asm/hwcap.h b/arch/arm64/include/asm/hwcap.h
index 9b5fdc1..cef4ae7 100644
--- a/arch/arm64/include/asm/hwcap.h
+++ b/arch/arm64/include/asm/hwcap.h
@@ -118,6 +118,7 @@
#define KERNEL_HWCAP_SME_F32F32 __khwcap2_feature(SME_F32F32)
#define KERNEL_HWCAP_SME_FA64 __khwcap2_feature(SME_FA64)
#define KERNEL_HWCAP_WFXT __khwcap2_feature(WFXT)
+#define KERNEL_HWCAP_EBF16 __khwcap2_feature(EBF16)
/*
* This yields a mask that user programs can use to figure out what
diff --git a/arch/arm64/include/uapi/asm/hwcap.h b/arch/arm64/include/uapi/asm/hwcap.h
index fd7577c..1ad2568 100644
--- a/arch/arm64/include/uapi/asm/hwcap.h
+++ b/arch/arm64/include/uapi/asm/hwcap.h
@@ -91,5 +91,6 @@
#define HWCAP2_SME_F32F32 (1 << 29)
#define HWCAP2_SME_FA64 (1 << 30)
#define HWCAP2_WFXT (1UL << 31)
+#define HWCAP2_EBF16 (1UL << 32)
#endif /* _UAPI__ASM_HWCAP_H */
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 5ba226f..c84f977 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -2623,6 +2623,7 @@
HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FRINTTS_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FRINT),
HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_SB_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_SB),
HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_BF16_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_BF16),
+ HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_BF16_SHIFT, 4, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_EBF16),
HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DGH_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DGH),
HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_I8MM_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_I8MM),
HWCAP_CAP(SYS_ID_AA64MMFR2_EL1, ID_AA64MMFR2_AT_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_USCAT),
diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
index 8eff0a3..2ca1312 100644
--- a/arch/arm64/kernel/cpuinfo.c
+++ b/arch/arm64/kernel/cpuinfo.c
@@ -107,6 +107,7 @@
[KERNEL_HWCAP_SME_F32F32] = "smef32f32",
[KERNEL_HWCAP_SME_FA64] = "smefa64",
[KERNEL_HWCAP_WFXT] = "wfxt",
+ [KERNEL_HWCAP_EBF16] = "ebf16",
};
#ifdef CONFIG_COMPAT
