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git.proxmox.com Git - mirror_ubuntu-eoan-kernel.git/blob - lib/gen_crc32table.c
2 #include "../include/generated/autoconf.h"
6 #define ENTRIES_PER_LINE 4
9 # define LE_TABLE_ROWS (CRC_LE_BITS/8)
10 # define LE_TABLE_SIZE 256
12 # define LE_TABLE_ROWS 1
13 # define LE_TABLE_SIZE (1 << CRC_LE_BITS)
17 # define BE_TABLE_ROWS (CRC_BE_BITS/8)
18 # define BE_TABLE_SIZE 256
20 # define BE_TABLE_ROWS 1
21 # define BE_TABLE_SIZE (1 << CRC_BE_BITS)
24 static uint32_t crc32table_le
[LE_TABLE_ROWS
][256];
25 static uint32_t crc32table_be
[BE_TABLE_ROWS
][256];
26 static uint32_t crc32ctable_le
[LE_TABLE_ROWS
][256];
29 * crc32init_le() - allocate and initialize LE table data
31 * crc is the crc of the byte i; other entries are filled in based on the
32 * fact that crctable[i^j] = crctable[i] ^ crctable[j].
35 static void crc32init_le_generic(const uint32_t polynomial
,
43 for (i
= LE_TABLE_SIZE
>> 1; i
; i
>>= 1) {
44 crc
= (crc
>> 1) ^ ((crc
& 1) ? polynomial
: 0);
45 for (j
= 0; j
< LE_TABLE_SIZE
; j
+= 2 * i
)
46 tab
[0][i
+ j
] = crc
^ tab
[0][j
];
48 for (i
= 0; i
< LE_TABLE_SIZE
; i
++) {
50 for (j
= 1; j
< LE_TABLE_ROWS
; j
++) {
51 crc
= tab
[0][crc
& 0xff] ^ (crc
>> 8);
57 static void crc32init_le(void)
59 crc32init_le_generic(CRCPOLY_LE
, crc32table_le
);
62 static void crc32cinit_le(void)
64 crc32init_le_generic(CRC32C_POLY_LE
, crc32ctable_le
);
68 * crc32init_be() - allocate and initialize BE table data
70 static void crc32init_be(void)
73 uint32_t crc
= 0x80000000;
75 crc32table_be
[0][0] = 0;
77 for (i
= 1; i
< BE_TABLE_SIZE
; i
<<= 1) {
78 crc
= (crc
<< 1) ^ ((crc
& 0x80000000) ? CRCPOLY_BE
: 0);
79 for (j
= 0; j
< i
; j
++)
80 crc32table_be
[0][i
+ j
] = crc
^ crc32table_be
[0][j
];
82 for (i
= 0; i
< BE_TABLE_SIZE
; i
++) {
83 crc
= crc32table_be
[0][i
];
84 for (j
= 1; j
< BE_TABLE_ROWS
; j
++) {
85 crc
= crc32table_be
[0][(crc
>> 24) & 0xff] ^ (crc
<< 8);
86 crc32table_be
[j
][i
] = crc
;
91 static void output_table(uint32_t (*table
)[256], int rows
, int len
, char *trans
)
95 for (j
= 0 ; j
< rows
; j
++) {
97 for (i
= 0; i
< len
- 1; i
++) {
98 if (i
% ENTRIES_PER_LINE
== 0)
100 printf("%s(0x%8.8xL), ", trans
, table
[j
][i
]);
102 printf("%s(0x%8.8xL)},\n", trans
, table
[j
][len
- 1]);
106 int main(int argc
, char** argv
)
108 printf("/* this file is generated - do not edit */\n\n");
110 if (CRC_LE_BITS
> 1) {
112 printf("static const u32 ____cacheline_aligned "
113 "crc32table_le[%d][%d] = {",
114 LE_TABLE_ROWS
, LE_TABLE_SIZE
);
115 output_table(crc32table_le
, LE_TABLE_ROWS
,
116 LE_TABLE_SIZE
, "tole");
120 if (CRC_BE_BITS
> 1) {
122 printf("static const u32 ____cacheline_aligned "
123 "crc32table_be[%d][%d] = {",
124 BE_TABLE_ROWS
, BE_TABLE_SIZE
);
125 output_table(crc32table_be
, LE_TABLE_ROWS
,
126 BE_TABLE_SIZE
, "tobe");
129 if (CRC_LE_BITS
> 1) {
131 printf("static const u32 ____cacheline_aligned "
132 "crc32ctable_le[%d][%d] = {",
133 LE_TABLE_ROWS
, LE_TABLE_SIZE
);
134 output_table(crc32ctable_le
, LE_TABLE_ROWS
,
135 LE_TABLE_SIZE
, "tole");