| xj | b04a402 | 2021-11-25 15:01:52 +0800 | [diff] [blame] | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | |
| 3 | /* Try to choose an implementation variant via Kconfig */ |
| 4 | #ifdef CONFIG_CRC32_SLICEBY8 |
| 5 | # define CRC_LE_BITS 64 |
| 6 | # define CRC_BE_BITS 64 |
| 7 | #endif |
| 8 | #ifdef CONFIG_CRC32_SLICEBY4 |
| 9 | # define CRC_LE_BITS 32 |
| 10 | # define CRC_BE_BITS 32 |
| 11 | #endif |
| 12 | #ifdef CONFIG_CRC32_SARWATE |
| 13 | # define CRC_LE_BITS 8 |
| 14 | # define CRC_BE_BITS 8 |
| 15 | #endif |
| 16 | #ifdef CONFIG_CRC32_BIT |
| 17 | # define CRC_LE_BITS 1 |
| 18 | # define CRC_BE_BITS 1 |
| 19 | #endif |
| 20 | |
| 21 | /* |
| 22 | * How many bits at a time to use. Valid values are 1, 2, 4, 8, 32 and 64. |
| 23 | * For less performance-sensitive, use 4 or 8 to save table size. |
| 24 | * For larger systems choose same as CPU architecture as default. |
| 25 | * This works well on X86_64, SPARC64 systems. This may require some |
| 26 | * elaboration after experiments with other architectures. |
| 27 | */ |
| 28 | #ifndef CRC_LE_BITS |
| 29 | # ifdef CONFIG_64BIT |
| 30 | # define CRC_LE_BITS 64 |
| 31 | # else |
| 32 | # define CRC_LE_BITS 32 |
| 33 | # endif |
| 34 | #endif |
| 35 | #ifndef CRC_BE_BITS |
| 36 | # ifdef CONFIG_64BIT |
| 37 | # define CRC_BE_BITS 64 |
| 38 | # else |
| 39 | # define CRC_BE_BITS 32 |
| 40 | # endif |
| 41 | #endif |
| 42 | |
| 43 | /* |
| 44 | * Little-endian CRC computation. Used with serial bit streams sent |
| 45 | * lsbit-first. Be sure to use cpu_to_le32() to append the computed CRC. |
| 46 | */ |
| 47 | #if CRC_LE_BITS > 64 || CRC_LE_BITS < 1 || CRC_LE_BITS == 16 || \ |
| 48 | CRC_LE_BITS & CRC_LE_BITS-1 |
| 49 | # error "CRC_LE_BITS must be one of {1, 2, 4, 8, 32, 64}" |
| 50 | #endif |
| 51 | |
| 52 | /* |
| 53 | * Big-endian CRC computation. Used with serial bit streams sent |
| 54 | * msbit-first. Be sure to use cpu_to_be32() to append the computed CRC. |
| 55 | */ |
| 56 | #if CRC_BE_BITS > 64 || CRC_BE_BITS < 1 || CRC_BE_BITS == 16 || \ |
| 57 | CRC_BE_BITS & CRC_BE_BITS-1 |
| 58 | # error "CRC_BE_BITS must be one of {1, 2, 4, 8, 32, 64}" |
| 59 | #endif |