xref: /openbmc/u-boot/lib/crc32c.c (revision ae485b54)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copied from Linux kernel crypto/crc32c.c
4  * Copyright (c) 2004 Cisco Systems, Inc.
5  * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License as published by the Free
9  * Software Foundation; either version 2 of the License, or (at your option)
10  * any later version.
11  */
12 
13 #include <common.h>
14 #include <compiler.h>
15 
16 uint32_t crc32c_cal(uint32_t crc, const char *data, int length,
17 		    uint32_t *crc32c_table)
18 {
19 	while (length--)
20 		crc = crc32c_table[(u8)(crc ^ *data++)] ^ (crc >> 8);
21 
22 	return crc;
23 }
24 
25 void crc32c_init(uint32_t *crc32c_table, uint32_t pol)
26 {
27 	int i, j;
28 	uint32_t v;
29 	const uint32_t poly = pol; /* Bit-reflected CRC32C polynomial */
30 
31 	for (i = 0; i < 256; i++) {
32 		v = i;
33 		for (j = 0; j < 8; j++)
34 			v = (v >> 1) ^ ((v & 1) ? poly : 0);
35 
36 		crc32c_table[i] = v;
37 	}
38 }
39