xref: /spdk/lib/util/crc32.c (revision 1fc4165fe9bf8512483356ad8e6d27f793f2e3db)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (c) Intel Corporation.
5  *   All rights reserved.
6  *
7  *   Redistribution and use in source and binary forms, with or without
8  *   modification, are permitted provided that the following conditions
9  *   are met:
10  *
11  *     * Redistributions of source code must retain the above copyright
12  *       notice, this list of conditions and the following disclaimer.
13  *     * Redistributions in binary form must reproduce the above copyright
14  *       notice, this list of conditions and the following disclaimer in
15  *       the documentation and/or other materials provided with the
16  *       distribution.
17  *     * Neither the name of Intel Corporation nor the names of its
18  *       contributors may be used to endorse or promote products derived
19  *       from this software without specific prior written permission.
20  *
21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include "spdk/crc32.h"
35 
36 void
37 spdk_crc32_table_init(struct spdk_crc32_table *table, uint32_t polynomial_reflect)
38 {
39 	int i, j;
40 	uint32_t val;
41 
42 	for (i = 0; i < 256; i++) {
43 		val = i;
44 		for (j = 0; j < 8; j++) {
45 			if (val & 1) {
46 				val = (val >> 1) ^ polynomial_reflect;
47 			} else {
48 				val = (val >> 1);
49 			}
50 		}
51 		table->table[i] = val;
52 	}
53 }
54 
55 #ifdef SPDK_HAVE_ARM_CRC
56 
57 uint32_t
58 spdk_crc32_update(const struct spdk_crc32_table *table, const void *buf, size_t len, uint32_t crc)
59 {
60 	size_t count;
61 	const uint64_t *dword_buf;
62 
63 	count = len & 7;
64 	while (count--) {
65 		crc = __crc32b(crc, *(const uint8_t *)buf);
66 		buf++;
67 	}
68 	dword_buf = (const uint64_t *)buf;
69 
70 	count = len / 8;
71 	while (count--) {
72 		crc = __crc32d(crc, *dword_buf);
73 		dword_buf++;
74 	}
75 
76 	return crc;
77 }
78 
79 #else
80 
81 uint32_t
82 spdk_crc32_update(const struct spdk_crc32_table *table, const void *buf, size_t len, uint32_t crc)
83 {
84 	const uint8_t *buf_u8 = buf;
85 	size_t i;
86 
87 	for (i = 0; i < len; i++) {
88 		crc = (crc >> 8) ^ table->table[(crc ^ buf_u8[i]) & 0xff];
89 	}
90 
91 	return crc;
92 }
93 
94 #endif
95