2 * There are multiple 16-bit CRC polynomials in common use, but this is
3 * *the* standard CRC-32 polynomial, first popularized by Ethernet.
4 * x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x^1+x^0
6 #define CRCPOLY_LE 0xedb88320
7 #define CRCPOLY_BE 0x04c11db7
10 * This is the CRC32c polynomial, as outlined by Castagnoli.
11 * x^32+x^28+x^27+x^26+x^25+x^23+x^22+x^20+x^19+x^18+x^14+x^13+x^11+x^10+x^9+
14 #define CRC32C_POLY_LE 0x82F63B78
16 /* Try to choose an implementation variant via Kconfig */
17 #ifdef CONFIG_CRC32_SLICEBY8
18 # define CRC_LE_BITS 64
19 # define CRC_BE_BITS 64
21 #ifdef CONFIG_CRC32_SLICEBY4
22 # define CRC_LE_BITS 32
23 # define CRC_BE_BITS 32
25 #ifdef CONFIG_CRC32_SARWATE
26 # define CRC_LE_BITS 8
27 # define CRC_BE_BITS 8
29 #ifdef CONFIG_CRC32_BIT
30 # define CRC_LE_BITS 1
31 # define CRC_BE_BITS 1
35 * How many bits at a time to use. Valid values are 1, 2, 4, 8, 32 and 64.
36 * For less performance-sensitive, use 4 or 8 to save table size.
37 * For larger systems choose same as CPU architecture as default.
38 * This works well on X86_64, SPARC64 systems. This may require some
39 * elaboration after experiments with other architectures.
43 # define CRC_LE_BITS 64
45 # define CRC_LE_BITS 32
50 # define CRC_BE_BITS 64
52 # define CRC_BE_BITS 32
57 * Little-endian CRC computation. Used with serial bit streams sent
58 * lsbit-first. Be sure to use cpu_to_le32() to append the computed CRC.
60 #if CRC_LE_BITS > 64 || CRC_LE_BITS < 1 || CRC_LE_BITS == 16 || \
61 CRC_LE_BITS & CRC_LE_BITS-1
62 # error "CRC_LE_BITS must be one of {1, 2, 4, 8, 32, 64}"
66 * Big-endian CRC computation. Used with serial bit streams sent
67 * msbit-first. Be sure to use cpu_to_be32() to append the computed CRC.
69 #if CRC_BE_BITS > 64 || CRC_BE_BITS < 1 || CRC_BE_BITS == 16 || \
70 CRC_BE_BITS & CRC_BE_BITS-1
71 # error "CRC_BE_BITS must be one of {1, 2, 4, 8, 32, 64}"