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 * How many bits at a time to use. Valid values are 1, 2, 4, 8, 32 and 64.
11 * For less performance-sensitive, use 4 or 8 to save table size.
12 * For larger systems choose same as CPU architecture as default.
13 * This works well on X86_64, SPARC64 systems. This may require some
14 * elaboration after experiments with other architectures.
18 # define CRC_LE_BITS 64
20 # define CRC_LE_BITS 32
25 # define CRC_BE_BITS 64
27 # define CRC_BE_BITS 32
32 * Little-endian CRC computation. Used with serial bit streams sent
33 * lsbit-first. Be sure to use cpu_to_le32() to append the computed CRC.
35 #if CRC_LE_BITS > 64 || CRC_LE_BITS < 1 || CRC_LE_BITS == 16 || \
36 CRC_LE_BITS & CRC_LE_BITS-1
37 # error "CRC_LE_BITS must be one of {1, 2, 4, 8, 32, 64}"
41 * Big-endian CRC computation. Used with serial bit streams sent
42 * msbit-first. Be sure to use cpu_to_be32() to append the computed CRC.
44 #if CRC_BE_BITS > 64 || CRC_BE_BITS < 1 || CRC_BE_BITS == 16 || \
45 CRC_BE_BITS & CRC_BE_BITS-1
46 # error "CRC_BE_BITS must be one of {1, 2, 4, 8, 32, 64}"