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4fb623074e
Before modifying the prototypes of kernel_neon_begin() and kernel_neon_end() to accommodate kernel mode FP/SIMD state buffers allocated on the stack, move arm64 to the new 'ksimd' scoped guard API, which encapsulates the calls to those functions. For symmetry, do the same for 32-bit ARM too. Reviewed-by: Eric Biggers <ebiggers@kernel.org> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
97 lines
2.4 KiB
C
97 lines
2.4 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Accelerated CRC32(C) using ARM CRC, NEON and Crypto Extensions instructions
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*
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* Copyright (C) 2016 Linaro Ltd <ard.biesheuvel@linaro.org>
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*/
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#include <linux/cpufeature.h>
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#include <asm/hwcap.h>
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#include <asm/simd.h>
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static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_crc32);
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static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_pmull);
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#define PMULL_MIN_LEN 64 /* min size of buffer for pmull functions */
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asmlinkage u32 crc32_pmull_le(const u8 buf[], u32 len, u32 init_crc);
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asmlinkage u32 crc32_armv8_le(u32 init_crc, const u8 buf[], u32 len);
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asmlinkage u32 crc32c_pmull_le(const u8 buf[], u32 len, u32 init_crc);
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asmlinkage u32 crc32c_armv8_le(u32 init_crc, const u8 buf[], u32 len);
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static inline u32 crc32_le_scalar(u32 crc, const u8 *p, size_t len)
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{
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if (static_branch_likely(&have_crc32))
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return crc32_armv8_le(crc, p, len);
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return crc32_le_base(crc, p, len);
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}
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static inline u32 crc32_le_arch(u32 crc, const u8 *p, size_t len)
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{
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if (len >= PMULL_MIN_LEN + 15 &&
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static_branch_likely(&have_pmull) && likely(may_use_simd())) {
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size_t n = -(uintptr_t)p & 15;
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/* align p to 16-byte boundary */
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if (n) {
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crc = crc32_le_scalar(crc, p, n);
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p += n;
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len -= n;
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}
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n = round_down(len, 16);
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scoped_ksimd()
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crc = crc32_pmull_le(p, n, crc);
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p += n;
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len -= n;
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}
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return crc32_le_scalar(crc, p, len);
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}
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static inline u32 crc32c_scalar(u32 crc, const u8 *p, size_t len)
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{
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if (static_branch_likely(&have_crc32))
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return crc32c_armv8_le(crc, p, len);
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return crc32c_base(crc, p, len);
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}
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static inline u32 crc32c_arch(u32 crc, const u8 *p, size_t len)
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{
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if (len >= PMULL_MIN_LEN + 15 &&
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static_branch_likely(&have_pmull) && likely(may_use_simd())) {
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size_t n = -(uintptr_t)p & 15;
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/* align p to 16-byte boundary */
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if (n) {
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crc = crc32c_scalar(crc, p, n);
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p += n;
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len -= n;
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}
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n = round_down(len, 16);
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scoped_ksimd()
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crc = crc32c_pmull_le(p, n, crc);
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p += n;
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len -= n;
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}
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return crc32c_scalar(crc, p, len);
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}
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#define crc32_be_arch crc32_be_base /* not implemented on this arch */
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#define crc32_mod_init_arch crc32_mod_init_arch
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static void crc32_mod_init_arch(void)
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{
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if (elf_hwcap2 & HWCAP2_CRC32)
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static_branch_enable(&have_crc32);
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if (elf_hwcap2 & HWCAP2_PMULL)
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static_branch_enable(&have_pmull);
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}
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static inline u32 crc32_optimizations_arch(void)
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{
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if (elf_hwcap2 & (HWCAP2_CRC32 | HWCAP2_PMULL))
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return CRC32_LE_OPTIMIZATION | CRC32C_OPTIMIZATION;
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return 0;
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}
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