diff options
Diffstat (limited to 'lib')
-rw-r--r-- | lib/crc32.c | 24 | ||||
-rw-r--r-- | lib/gen_crc32table.c | 47 |
2 files changed, 47 insertions, 24 deletions
diff --git a/lib/crc32.c b/lib/crc32.c index bc5b936e914..4855995fcde 100644 --- a/lib/crc32.c +++ b/lib/crc32.c | |||
@@ -48,12 +48,20 @@ MODULE_LICENSE("GPL"); | |||
48 | #if CRC_LE_BITS == 8 || CRC_BE_BITS == 8 | 48 | #if CRC_LE_BITS == 8 || CRC_BE_BITS == 8 |
49 | 49 | ||
50 | static inline u32 | 50 | static inline u32 |
51 | crc32_body(u32 crc, unsigned char const *buf, size_t len, const u32 *tab) | 51 | crc32_body(u32 crc, unsigned char const *buf, size_t len, const u32 (*tab)[256]) |
52 | { | 52 | { |
53 | # ifdef __LITTLE_ENDIAN | 53 | # ifdef __LITTLE_ENDIAN |
54 | # define DO_CRC(x) crc = tab[(crc ^ (x)) & 255 ] ^ (crc >> 8) | 54 | # define DO_CRC(x) crc = tab[0][(crc ^ (x)) & 255] ^ (crc >> 8) |
55 | # define DO_CRC4 crc = tab[3][(crc) & 255] ^ \ | ||
56 | tab[2][(crc >> 8) & 255] ^ \ | ||
57 | tab[1][(crc >> 16) & 255] ^ \ | ||
58 | tab[0][(crc >> 24) & 255] | ||
55 | # else | 59 | # else |
56 | # define DO_CRC(x) crc = tab[((crc >> 24) ^ (x)) & 255] ^ (crc << 8) | 60 | # define DO_CRC(x) crc = tab[0][((crc >> 24) ^ (x)) & 255] ^ (crc << 8) |
61 | # define DO_CRC4 crc = tab[0][(crc) & 255] ^ \ | ||
62 | tab[1][(crc >> 8) & 255] ^ \ | ||
63 | tab[2][(crc >> 16) & 255] ^ \ | ||
64 | tab[3][(crc >> 24) & 255] | ||
57 | # endif | 65 | # endif |
58 | const u32 *b; | 66 | const u32 *b; |
59 | size_t rem_len; | 67 | size_t rem_len; |
@@ -70,10 +78,7 @@ crc32_body(u32 crc, unsigned char const *buf, size_t len, const u32 *tab) | |||
70 | b = (const u32 *)buf; | 78 | b = (const u32 *)buf; |
71 | for (--b; len; --len) { | 79 | for (--b; len; --len) { |
72 | crc ^= *++b; /* use pre increment for speed */ | 80 | crc ^= *++b; /* use pre increment for speed */ |
73 | DO_CRC(0); | 81 | DO_CRC4; |
74 | DO_CRC(0); | ||
75 | DO_CRC(0); | ||
76 | DO_CRC(0); | ||
77 | } | 82 | } |
78 | len = rem_len; | 83 | len = rem_len; |
79 | /* And the last few bytes */ | 84 | /* And the last few bytes */ |
@@ -85,6 +90,7 @@ crc32_body(u32 crc, unsigned char const *buf, size_t len, const u32 *tab) | |||
85 | } | 90 | } |
86 | return crc; | 91 | return crc; |
87 | #undef DO_CRC | 92 | #undef DO_CRC |
93 | #undef DO_CRC4 | ||
88 | } | 94 | } |
89 | #endif | 95 | #endif |
90 | /** | 96 | /** |
@@ -117,7 +123,7 @@ u32 __pure crc32_le(u32 crc, unsigned char const *p, size_t len) | |||
117 | u32 __pure crc32_le(u32 crc, unsigned char const *p, size_t len) | 123 | u32 __pure crc32_le(u32 crc, unsigned char const *p, size_t len) |
118 | { | 124 | { |
119 | # if CRC_LE_BITS == 8 | 125 | # if CRC_LE_BITS == 8 |
120 | const u32 *tab = crc32table_le; | 126 | const u32 (*tab)[] = crc32table_le; |
121 | 127 | ||
122 | crc = __cpu_to_le32(crc); | 128 | crc = __cpu_to_le32(crc); |
123 | crc = crc32_body(crc, p, len, tab); | 129 | crc = crc32_body(crc, p, len, tab); |
@@ -174,7 +180,7 @@ u32 __pure crc32_be(u32 crc, unsigned char const *p, size_t len) | |||
174 | u32 __pure crc32_be(u32 crc, unsigned char const *p, size_t len) | 180 | u32 __pure crc32_be(u32 crc, unsigned char const *p, size_t len) |
175 | { | 181 | { |
176 | # if CRC_BE_BITS == 8 | 182 | # if CRC_BE_BITS == 8 |
177 | const u32 *tab = crc32table_be; | 183 | const u32 (*tab)[] = crc32table_be; |
178 | 184 | ||
179 | crc = __cpu_to_be32(crc); | 185 | crc = __cpu_to_be32(crc); |
180 | crc = crc32_body(crc, p, len, tab); | 186 | crc = crc32_body(crc, p, len, tab); |
diff --git a/lib/gen_crc32table.c b/lib/gen_crc32table.c index bea5d97df99..85d0e412a04 100644 --- a/lib/gen_crc32table.c +++ b/lib/gen_crc32table.c | |||
@@ -7,8 +7,8 @@ | |||
7 | #define LE_TABLE_SIZE (1 << CRC_LE_BITS) | 7 | #define LE_TABLE_SIZE (1 << CRC_LE_BITS) |
8 | #define BE_TABLE_SIZE (1 << CRC_BE_BITS) | 8 | #define BE_TABLE_SIZE (1 << CRC_BE_BITS) |
9 | 9 | ||
10 | static uint32_t crc32table_le[LE_TABLE_SIZE]; | 10 | static uint32_t crc32table_le[4][LE_TABLE_SIZE]; |
11 | static uint32_t crc32table_be[BE_TABLE_SIZE]; | 11 | static uint32_t crc32table_be[4][BE_TABLE_SIZE]; |
12 | 12 | ||
13 | /** | 13 | /** |
14 | * crc32init_le() - allocate and initialize LE table data | 14 | * crc32init_le() - allocate and initialize LE table data |
@@ -22,12 +22,19 @@ static void crc32init_le(void) | |||
22 | unsigned i, j; | 22 | unsigned i, j; |
23 | uint32_t crc = 1; | 23 | uint32_t crc = 1; |
24 | 24 | ||
25 | crc32table_le[0] = 0; | 25 | crc32table_le[0][0] = 0; |
26 | 26 | ||
27 | for (i = 1 << (CRC_LE_BITS - 1); i; i >>= 1) { | 27 | for (i = 1 << (CRC_LE_BITS - 1); i; i >>= 1) { |
28 | crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0); | 28 | crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0); |
29 | for (j = 0; j < LE_TABLE_SIZE; j += 2 * i) | 29 | for (j = 0; j < LE_TABLE_SIZE; j += 2 * i) |
30 | crc32table_le[i + j] = crc ^ crc32table_le[j]; | 30 | crc32table_le[0][i + j] = crc ^ crc32table_le[0][j]; |
31 | } | ||
32 | for (i = 0; i < LE_TABLE_SIZE; i++) { | ||
33 | crc = crc32table_le[0][i]; | ||
34 | for (j = 1; j < 4; j++) { | ||
35 | crc = crc32table_le[0][crc & 0xff] ^ (crc >> 8); | ||
36 | crc32table_le[j][i] = crc; | ||
37 | } | ||
31 | } | 38 | } |
32 | } | 39 | } |
33 | 40 | ||
@@ -39,25 +46,35 @@ static void crc32init_be(void) | |||
39 | unsigned i, j; | 46 | unsigned i, j; |
40 | uint32_t crc = 0x80000000; | 47 | uint32_t crc = 0x80000000; |
41 | 48 | ||
42 | crc32table_be[0] = 0; | 49 | crc32table_be[0][0] = 0; |
43 | 50 | ||
44 | for (i = 1; i < BE_TABLE_SIZE; i <<= 1) { | 51 | for (i = 1; i < BE_TABLE_SIZE; i <<= 1) { |
45 | crc = (crc << 1) ^ ((crc & 0x80000000) ? CRCPOLY_BE : 0); | 52 | crc = (crc << 1) ^ ((crc & 0x80000000) ? CRCPOLY_BE : 0); |
46 | for (j = 0; j < i; j++) | 53 | for (j = 0; j < i; j++) |
47 | crc32table_be[i + j] = crc ^ crc32table_be[j]; | 54 | crc32table_be[0][i + j] = crc ^ crc32table_be[0][j]; |
55 | } | ||
56 | for (i = 0; i < BE_TABLE_SIZE; i++) { | ||
57 | crc = crc32table_be[0][i]; | ||
58 | for (j = 1; j < 4; j++) { | ||
59 | crc = crc32table_be[0][(crc >> 24) & 0xff] ^ (crc << 8); | ||
60 | crc32table_be[j][i] = crc; | ||
61 | } | ||
48 | } | 62 | } |
49 | } | 63 | } |
50 | 64 | ||
51 | static void output_table(uint32_t table[], int len, char *trans) | 65 | static void output_table(uint32_t table[4][256], int len, char *trans) |
52 | { | 66 | { |
53 | int i; | 67 | int i, j; |
54 | 68 | ||
55 | for (i = 0; i < len - 1; i++) { | 69 | for (j = 0 ; j < 4; j++) { |
56 | if (i % ENTRIES_PER_LINE == 0) | 70 | printf("{"); |
57 | printf("\n"); | 71 | for (i = 0; i < len - 1; i++) { |
58 | printf("%s(0x%8.8xL), ", trans, table[i]); | 72 | if (i % ENTRIES_PER_LINE == 0) |
73 | printf("\n"); | ||
74 | printf("%s(0x%8.8xL), ", trans, table[j][i]); | ||
75 | } | ||
76 | printf("%s(0x%8.8xL)},\n", trans, table[j][len - 1]); | ||
59 | } | 77 | } |
60 | printf("%s(0x%8.8xL)\n", trans, table[len - 1]); | ||
61 | } | 78 | } |
62 | 79 | ||
63 | int main(int argc, char** argv) | 80 | int main(int argc, char** argv) |
@@ -66,14 +83,14 @@ int main(int argc, char** argv) | |||
66 | 83 | ||
67 | if (CRC_LE_BITS > 1) { | 84 | if (CRC_LE_BITS > 1) { |
68 | crc32init_le(); | 85 | crc32init_le(); |
69 | printf("static const u32 crc32table_le[] = {"); | 86 | printf("static const u32 crc32table_le[4][256] = {"); |
70 | output_table(crc32table_le, LE_TABLE_SIZE, "tole"); | 87 | output_table(crc32table_le, LE_TABLE_SIZE, "tole"); |
71 | printf("};\n"); | 88 | printf("};\n"); |
72 | } | 89 | } |
73 | 90 | ||
74 | if (CRC_BE_BITS > 1) { | 91 | if (CRC_BE_BITS > 1) { |
75 | crc32init_be(); | 92 | crc32init_be(); |
76 | printf("static const u32 crc32table_be[] = {"); | 93 | printf("static const u32 crc32table_be[4][256] = {"); |
77 | output_table(crc32table_be, BE_TABLE_SIZE, "tobe"); | 94 | output_table(crc32table_be, BE_TABLE_SIZE, "tobe"); |
78 | printf("};\n"); | 95 | printf("};\n"); |
79 | } | 96 | } |