mirror of
https://github.com/torvalds/linux
synced 2024-11-05 18:23:50 +00:00
1fb2e3f276
Allow other drivers and parts of kernel to use the same define for CRC32 polynomial, instead of duplicating it in many places. This code does not bring any functional changes, except moving existing code. Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
59 lines
1.6 KiB
C
59 lines
1.6 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
|
|
/* Try to choose an implementation variant via Kconfig */
|
|
#ifdef CONFIG_CRC32_SLICEBY8
|
|
# define CRC_LE_BITS 64
|
|
# define CRC_BE_BITS 64
|
|
#endif
|
|
#ifdef CONFIG_CRC32_SLICEBY4
|
|
# define CRC_LE_BITS 32
|
|
# define CRC_BE_BITS 32
|
|
#endif
|
|
#ifdef CONFIG_CRC32_SARWATE
|
|
# define CRC_LE_BITS 8
|
|
# define CRC_BE_BITS 8
|
|
#endif
|
|
#ifdef CONFIG_CRC32_BIT
|
|
# define CRC_LE_BITS 1
|
|
# define CRC_BE_BITS 1
|
|
#endif
|
|
|
|
/*
|
|
* How many bits at a time to use. Valid values are 1, 2, 4, 8, 32 and 64.
|
|
* For less performance-sensitive, use 4 or 8 to save table size.
|
|
* For larger systems choose same as CPU architecture as default.
|
|
* This works well on X86_64, SPARC64 systems. This may require some
|
|
* elaboration after experiments with other architectures.
|
|
*/
|
|
#ifndef CRC_LE_BITS
|
|
# ifdef CONFIG_64BIT
|
|
# define CRC_LE_BITS 64
|
|
# else
|
|
# define CRC_LE_BITS 32
|
|
# endif
|
|
#endif
|
|
#ifndef CRC_BE_BITS
|
|
# ifdef CONFIG_64BIT
|
|
# define CRC_BE_BITS 64
|
|
# else
|
|
# define CRC_BE_BITS 32
|
|
# endif
|
|
#endif
|
|
|
|
/*
|
|
* Little-endian CRC computation. Used with serial bit streams sent
|
|
* lsbit-first. Be sure to use cpu_to_le32() to append the computed CRC.
|
|
*/
|
|
#if CRC_LE_BITS > 64 || CRC_LE_BITS < 1 || CRC_LE_BITS == 16 || \
|
|
CRC_LE_BITS & CRC_LE_BITS-1
|
|
# error "CRC_LE_BITS must be one of {1, 2, 4, 8, 32, 64}"
|
|
#endif
|
|
|
|
/*
|
|
* Big-endian CRC computation. Used with serial bit streams sent
|
|
* msbit-first. Be sure to use cpu_to_be32() to append the computed CRC.
|
|
*/
|
|
#if CRC_BE_BITS > 64 || CRC_BE_BITS < 1 || CRC_BE_BITS == 16 || \
|
|
CRC_BE_BITS & CRC_BE_BITS-1
|
|
# error "CRC_BE_BITS must be one of {1, 2, 4, 8, 32, 64}"
|
|
#endif
|