From: Amit Daniel Kachhap Date: Thu, 17 Nov 2022 05:37:21 +0000 (+0100) Subject: ARM: 9270/1: vfp: Add hwcap for FEAT_FHM X-Git-Tag: v6.2-rc1~101^2~8 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=ce4835497c20;p=thirdparty%2Flinux.git ARM: 9270/1: vfp: Add hwcap for FEAT_FHM Floating-point half-precision multiplication (FHM) is a feature present in AArch32 state for Armv8 and is represented by ISAR6.FHM identification register. This feature denotes the presence of VFMAL and VMFSL 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 64f3608e6f1bf..3d168d4f2a51e 100644 --- a/arch/arm/include/uapi/asm/hwcap.h +++ b/arch/arm/include/uapi/asm/hwcap.h @@ -31,6 +31,7 @@ #define HWCAP_FPHP (1 << 22) #define HWCAP_ASIMDHP (1 << 23) #define HWCAP_ASIMDDP (1 << 24) +#define HWCAP_ASIMDFHM (1 << 25) /* * 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 9841b897d476c..d88c1326f529a 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -1252,6 +1252,7 @@ static const char *hwcap_str[] = { "fphp", "asimdhp", "asimddp", + "asimdfhm", NULL }; diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c index 70f1e0f4eece8..404c4f9011329 100644 --- a/arch/arm/vfp/vfpmodule.c +++ b/arch/arm/vfp/vfpmodule.c @@ -845,6 +845,12 @@ static int __init vfp_init(void) isar6 = read_cpuid_ext(CPUID_EXT_ISAR6); if (cpuid_feature_extract_field(isar6, 4) == 0x1) elf_hwcap |= HWCAP_ASIMDDP; + /* + * Check for the presence of Advanced SIMD Floating point + * half-precision multiplication instructions. + */ + if (cpuid_feature_extract_field(isar6, 8) == 0x1) + elf_hwcap |= HWCAP_ASIMDFHM; /* Extract the architecture version on pre-cpuid scheme */ } else {