1*961df833SKyungmin Park /* 2*961df833SKyungmin Park * There are multiple 16-bit CRC polynomials in common use, but this is 3*961df833SKyungmin Park * *the* standard CRC-32 polynomial, first popularized by Ethernet. 4*961df833SKyungmin Park * 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*961df833SKyungmin Park */ 6*961df833SKyungmin Park #define CRCPOLY_LE 0xedb88320 7*961df833SKyungmin Park #define CRCPOLY_BE 0x04c11db7 8*961df833SKyungmin Park 9*961df833SKyungmin Park /* How many bits at a time to use. Requires a table of 4<<CRC_xx_BITS bytes. */ 10*961df833SKyungmin Park /* For less performance-sensitive, use 4 */ 11*961df833SKyungmin Park #ifndef CRC_LE_BITS 12*961df833SKyungmin Park # define CRC_LE_BITS 8 13*961df833SKyungmin Park #endif 14*961df833SKyungmin Park #ifndef CRC_BE_BITS 15*961df833SKyungmin Park # define CRC_BE_BITS 8 16*961df833SKyungmin Park #endif 17*961df833SKyungmin Park 18*961df833SKyungmin Park /* 19*961df833SKyungmin Park * Little-endian CRC computation. Used with serial bit streams sent 20*961df833SKyungmin Park * lsbit-first. Be sure to use cpu_to_le32() to append the computed CRC. 21*961df833SKyungmin Park */ 22*961df833SKyungmin Park #if CRC_LE_BITS > 8 || CRC_LE_BITS < 1 || CRC_LE_BITS & CRC_LE_BITS-1 23*961df833SKyungmin Park # error CRC_LE_BITS must be a power of 2 between 1 and 8 24*961df833SKyungmin Park #endif 25*961df833SKyungmin Park 26*961df833SKyungmin Park /* 27*961df833SKyungmin Park * Big-endian CRC computation. Used with serial bit streams sent 28*961df833SKyungmin Park * msbit-first. Be sure to use cpu_to_be32() to append the computed CRC. 29*961df833SKyungmin Park */ 30*961df833SKyungmin Park #if CRC_BE_BITS > 8 || CRC_BE_BITS < 1 || CRC_BE_BITS & CRC_BE_BITS-1 31*961df833SKyungmin Park # error CRC_BE_BITS must be a power of 2 between 1 and 8 32*961df833SKyungmin Park #endif 33