linux/lib/crc/loongarch/crc32.h
Eric Biggers b10d2d20d9 lib/crc: loongarch: Migrate optimized CRC code into lib/crc/
Move the loongarch-optimized CRC code from arch/loongarch/lib/crc* into
its new location in lib/crc/loongarch/, and wire it up in the new way.
This new way of organizing the CRC code eliminates the need to
artificially split the code for each CRC variant into separate arch and
generic modules, enabling better inlining and dead code elimination.
For more details, see "lib/crc: Prepare for arch-optimized code in
subdirs of lib/crc/".

Reviewed-by: "Martin K. Petersen" <martin.petersen@oracle.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: "Jason A. Donenfeld" <Jason@zx2c4.com>
Link: https://lore.kernel.org/r/20250607200454.73587-6-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2025-06-30 09:31:57 -07:00

115 lines
2.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* CRC32 and CRC32C using LoongArch crc* instructions
*
* Module based on mips/crypto/crc32-mips.c
*
* Copyright (C) 2014 Linaro Ltd <yazen.ghannam@linaro.org>
* Copyright (C) 2018 MIPS Tech, LLC
* Copyright (C) 2020-2023 Loongson Technology Corporation Limited
*/
#include <asm/cpu-features.h>
#include <linux/unaligned.h>
#define _CRC32(crc, value, size, type) \
do { \
__asm__ __volatile__( \
#type ".w." #size ".w" " %0, %1, %0\n\t"\
: "+r" (crc) \
: "r" (value) \
: "memory"); \
} while (0)
#define CRC32(crc, value, size) _CRC32(crc, value, size, crc)
#define CRC32C(crc, value, size) _CRC32(crc, value, size, crcc)
static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_crc32);
static inline u32 crc32_le_arch(u32 crc, const u8 *p, size_t len)
{
if (!static_branch_likely(&have_crc32))
return crc32_le_base(crc, p, len);
while (len >= sizeof(u64)) {
u64 value = get_unaligned_le64(p);
CRC32(crc, value, d);
p += sizeof(u64);
len -= sizeof(u64);
}
if (len & sizeof(u32)) {
u32 value = get_unaligned_le32(p);
CRC32(crc, value, w);
p += sizeof(u32);
}
if (len & sizeof(u16)) {
u16 value = get_unaligned_le16(p);
CRC32(crc, value, h);
p += sizeof(u16);
}
if (len & sizeof(u8)) {
u8 value = *p++;
CRC32(crc, value, b);
}
return crc;
}
static inline u32 crc32c_arch(u32 crc, const u8 *p, size_t len)
{
if (!static_branch_likely(&have_crc32))
return crc32c_base(crc, p, len);
while (len >= sizeof(u64)) {
u64 value = get_unaligned_le64(p);
CRC32C(crc, value, d);
p += sizeof(u64);
len -= sizeof(u64);
}
if (len & sizeof(u32)) {
u32 value = get_unaligned_le32(p);
CRC32C(crc, value, w);
p += sizeof(u32);
}
if (len & sizeof(u16)) {
u16 value = get_unaligned_le16(p);
CRC32C(crc, value, h);
p += sizeof(u16);
}
if (len & sizeof(u8)) {
u8 value = *p++;
CRC32C(crc, value, b);
}
return crc;
}
#define crc32_be_arch crc32_be_base /* not implemented on this arch */
#define crc32_mod_init_arch crc32_mod_init_arch
static inline void crc32_mod_init_arch(void)
{
if (cpu_has_crc32)
static_branch_enable(&have_crc32);
}
static inline u32 crc32_optimizations_arch(void)
{
if (static_key_enabled(&have_crc32))
return CRC32_LE_OPTIMIZATION | CRC32C_OPTIMIZATION;
return 0;
}