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| author | Amit Daniel Kachhap <amit.kachhap@arm.com> | 2022-11-17 08:37:21 +0300 |
|---|---|---|
| committer | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2022-11-28 14:57:33 +0300 |
| commit | ce4835497c20991574fde492ab37ec666563d3e4 (patch) | |
| tree | fc5b68f7321f1e1b76bcf147275fe343ea2318e2 | |
| parent | 62ea0d873af3ef0a7e8387b67241ad43e3d377e1 (diff) | |
| download | linux-ce4835497c20991574fde492ab37ec666563d3e4.tar.xz | |
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 <linus.walleij@linaro.org>
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
| -rw-r--r-- | arch/arm/include/uapi/asm/hwcap.h | 1 | ||||
| -rw-r--r-- | arch/arm/kernel/setup.c | 1 | ||||
| -rw-r--r-- | arch/arm/vfp/vfpmodule.c | 6 |
3 files changed, 8 insertions, 0 deletions
diff --git a/arch/arm/include/uapi/asm/hwcap.h b/arch/arm/include/uapi/asm/hwcap.h index 64f3608e6f1b..3d168d4f2a51 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 9841b897d476..d88c1326f529 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 70f1e0f4eece..404c4f901132 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 { |