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Diffstat (limited to '')
-rw-r--r-- | lib/crc32defs.h | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/lib/crc32defs.h b/lib/crc32defs.h new file mode 100644 index 0000000000..0c8fb5923e --- /dev/null +++ b/lib/crc32defs.h @@ -0,0 +1,59 @@ +/* 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 |