GNUBoot/coreboot-kgpe-d16
2
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

lib/crc_byte: Add CRC32 implementation

Browse source 
* Add CRC32 using polynomial 0x04C11DB7
+ Add macro to caculate CRC of a buffer

Change-Id: If98e4e12bb53a6e5123e94e8cdffde1eb3bc4b4b
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/37753
Reviewed-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
This commit is contained in:
Patrick Rudolph 2019-12-15 18:03:36 +01:00
parent 389c827943
commit cc0b6f18cd
2 changed files with 33 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

19
src/include/crc_byte.h
View file

@ -36,5 +36,24 @@ uint8_t crc7_byte(uint8_t prev_crc, uint8_t data);
*/
uint16_t crc16_byte(uint16_t prev_crc, uint8_t data);
/* This function is used to calculate crc32 byte by byte, with polynomial
* 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
*
* prev_crc: old crc result (0 for first)
* data: new byte
* return value: new crc result
*/
uint32_t crc32_byte(uint32_t prev_crc, uint8_t data);
#define CRC(buf, size, crc_func) ({ \
const uint8_t *_crc_local_buf = (const uint8_t *)buf; \
size_t _crc_local_size = size; \
__typeof__(crc_func(0, 0)) _crc_local_result = 0; \
while (_crc_local_size--) { \
_crc_local_result = crc_func(_crc_local_result, *_crc_local_buf++); \
} \
_crc_local_result; \
})
#endif /* CRC_BYTE_H */

14
src/lib/crc_byte.c
View file

@ -36,3 +36,17 @@ uint16_t crc16_byte(uint16_t prev_crc, uint8_t data)
prev_crc ^= ((prev_crc & 0xff) << 4) << 1;
return prev_crc;
}
uint32_t crc32_byte(uint32_t prev_crc, uint8_t data)
{
prev_crc ^= (uint32_t)data << 24;
for (int i = 0; i < 8; i++) {
if ((prev_crc & 0x80000000UL) != 0)
prev_crc = ((prev_crc << 1) ^ 0x04C11DB7UL);
else
prev_crc <<= 1;
}
return prev_crc;
}