arm64: v8.4: Support for new floating point multiplication instructions
authorDongjiu Geng <gengdongjiu@huawei.com>
Wed, 13 Dec 2017 10:13:56 +0000 (18:13 +0800)
committerCatalin Marinas <catalin.marinas@arm.com>
Fri, 5 Jan 2018 11:29:48 +0000 (11:29 +0000)
commit3b3b681097fae73b7f5dcdd42db6cfdf32943d4c
tree514122d4fd4358c7dfda62c2294ad31215e0aed6
parenta8ffaaa060b8d4da6138e0958cb0f45b73e1cb78
arm64: v8.4: Support for new floating point multiplication instructions

ARM v8.4 extensions add new neon instructions for performing a
multiplication of each FP16 element of one vector with the corresponding
FP16 element of a second vector, and to add or subtract this without an
intermediate rounding to the corresponding FP32 element in a third vector.

This patch detects this feature and let the userspace know about it via a
HWCAP bit and MRS emulation.

Cc: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Documentation/arm64/cpu-feature-registers.txt
Documentation/arm64/elf_hwcaps.txt
arch/arm64/include/asm/sysreg.h
arch/arm64/include/uapi/asm/hwcap.h
arch/arm64/kernel/cpufeature.c
arch/arm64/kernel/cpuinfo.c