1/* 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 5 */ 6#define CRCPOLY_LE 0xedb88320 7#define CRCPOLY_BE 0x04c11db7 8 9/* How many bits at a time to use. Requires a table of 4<<CRC_xx_BITS bytes. */ 10/* For less performance-sensitive, use 4 */ 11#ifndef CRC_LE_BITS 12# define CRC_LE_BITS 8 13#endif 14#ifndef CRC_BE_BITS 15# define CRC_BE_BITS 8 16#endif 17 18/* 19 * Little-endian CRC computation. Used with serial bit streams sent 20 * lsbit-first. Be sure to use cpu_to_le32() to append the computed CRC. 21 */ 22#if CRC_LE_BITS > 8 || CRC_LE_BITS < 1 || CRC_LE_BITS & CRC_LE_BITS-1 23# error CRC_LE_BITS must be a power of 2 between 1 and 8 24#endif 25 26/* 27 * Big-endian CRC computation. Used with serial bit streams sent 28 * msbit-first. Be sure to use cpu_to_be32() to append the computed CRC. 29 */ 30#if CRC_BE_BITS > 8 || CRC_BE_BITS < 1 || CRC_BE_BITS & CRC_BE_BITS-1 31# error CRC_BE_BITS must be a power of 2 between 1 and 8 32#endif 33