kernel-ark/lib/crc32defs.h

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/*
* There are multiple 16-bit CRC polynomials in common use, but this is
* *the* standard CRC-32 polynomial, first popularized by Ethernet.
* 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
*/
#define CRCPOLY_LE 0xedb88320
#define CRCPOLY_BE 0x04c11db7
/* How many bits at a time to use. Requires a table of 4<<CRC_xx_BITS bytes. */
/* For less performance-sensitive, use 4 */
#ifndef CRC_LE_BITS
# define CRC_LE_BITS 8
#endif
#ifndef CRC_BE_BITS
# define CRC_BE_BITS 8
#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 > 8 || CRC_LE_BITS < 1 || CRC_LE_BITS & CRC_LE_BITS-1
# error CRC_LE_BITS must be a power of 2 between 1 and 8
#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 > 8 || CRC_BE_BITS < 1 || CRC_BE_BITS & CRC_BE_BITS-1
# error CRC_BE_BITS must be a power of 2 between 1 and 8
#endif