From: Amit Daniel Kachhap Date: Thu, 17 Nov 2022 05:42:07 +0000 (+0100) Subject: ARM: 9271/1: vfp: Add hwcap for FEAT_AA32BF16 X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=23b6d4ad6e7a;p=linux.git ARM: 9271/1: vfp: Add hwcap for FEAT_AA32BF16 Advanced SIMD BFloat16 (FEAT_AA32BF16) is a feature present in AArch32 state for Armv8 and is represented by ISAR6.BF16 identification register. This feature denotes the presence of VCVT, VCVTB, VCVTT, VDOT, VFMAB, VFMAT and VMMLA instructions and hence adding a hwcap will enable the userspace to check it before trying to use those instructions. Reviewed-by: Linus Walleij Signed-off-by: Amit Daniel Kachhap Signed-off-by: Russell King (Oracle) --- diff --git a/arch/arm/include/uapi/asm/hwcap.h b/arch/arm/include/uapi/asm/hwcap.h index 3d168d4f2a51e..14e260e2d6d0c 100644 --- a/arch/arm/include/uapi/asm/hwcap.h +++ b/arch/arm/include/uapi/asm/hwcap.h @@ -32,6 +32,7 @@ #define HWCAP_ASIMDHP (1 << 23) #define HWCAP_ASIMDDP (1 << 24) #define HWCAP_ASIMDFHM (1 << 25) +#define HWCAP_ASIMDBF16 (1 << 26) /* * HWCAP2 flags - for elf_hwcap2 (in kernel) and AT_HWCAP2 diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index d88c1326f529a..070067cb6c77a 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -1253,6 +1253,7 @@ static const char *hwcap_str[] = { "asimdhp", "asimddp", "asimdfhm", + "asimdbf16", NULL }; diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c index 404c4f9011329..ff574cb8a0b92 100644 --- a/arch/arm/vfp/vfpmodule.c +++ b/arch/arm/vfp/vfpmodule.c @@ -851,6 +851,12 @@ static int __init vfp_init(void) */ if (cpuid_feature_extract_field(isar6, 8) == 0x1) elf_hwcap |= HWCAP_ASIMDFHM; + /* + * Check for the presence of Advanced SIMD Bfloat16 + * floating point instructions. + */ + if (cpuid_feature_extract_field(isar6, 20) == 0x1) + elf_hwcap |= HWCAP_ASIMDBF16; /* Extract the architecture version on pre-cpuid scheme */ } else {