xref: /aosp_15_r20/external/coreboot/src/include/crc_byte.h (revision b9411a12aaaa7e1e6a6fb7c5e057f44ee179a49c)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 
3 #ifndef CRC_BYTE_H
4 #define CRC_BYTE_H
5 
6 #include <stddef.h>
7 #include <stdint.h>
8 
9 /* This function is used to calculate crc7 byte by byte, with polynomial
10  * x^7 + x^3 + 1.
11  *
12  * prev_crc: old crc result (0 for first)
13  * data: new byte
14  * return value: new crc result
15  */
16 uint8_t crc7_byte(uint8_t prev_crc, uint8_t data);
17 
18 /* This function is used to calculate crc16 byte by byte, with polynomial
19  * x^16 + x^12 + x^5 + 1.
20  *
21  * prev_crc: old crc result (0 for first)
22  * data: new byte
23  * return value: new crc result
24  */
25 uint16_t crc16_byte(uint16_t prev_crc, uint8_t data);
26 
27 /* This function is used to calculate crc32 byte by byte, with polynomial
28  * x^32 + x^26 +  x^23 + x^22 + x^16 + x^12 + x^11 + x^10 + x^8 + x^7 +
29  * x^5 + x^4 + x^2 + x + 1
30  *
31  * prev_crc: old crc result (0 for first)
32  * data: new byte
33  * return value: new crc result
34  */
35 uint32_t crc32_byte(uint32_t prev_crc, uint8_t data);
36 
37 #define CRC(buf, size, crc_func) ({ \
38 	const uint8_t *_crc_local_buf = (const uint8_t *)buf; \
39 	size_t _crc_local_size = size; \
40 	__typeof__(crc_func(0, 0)) _crc_local_result = 0; \
41 	while (_crc_local_size--) { \
42 		_crc_local_result = crc_func(_crc_local_result, *_crc_local_buf++); \
43 	} \
44 	_crc_local_result; \
45 })
46 
47 #endif /* CRC_BYTE_H */
48