1 // SPDX-License-Identifier: GPL-2.0 2 #include <stdio.h> 3 #include "../include/linux/crc32poly.h" 4 #include "../include/generated/autoconf.h" 5 #include "crc32defs.h" 6 #include <inttypes.h> 7 8 #define ENTRIES_PER_LINE 4 9 10 #if CRC_LE_BITS > 8 11 # define LE_TABLE_ROWS (CRC_LE_BITS/8) 12 # define LE_TABLE_SIZE 256 13 #else 14 # define LE_TABLE_ROWS 1 15 # define LE_TABLE_SIZE (1 << CRC_LE_BITS) 16 #endif 17 18 #if CRC_BE_BITS > 8 19 # define BE_TABLE_ROWS (CRC_BE_BITS/8) 20 # define BE_TABLE_SIZE 256 21 #else 22 # define BE_TABLE_ROWS 1 23 # define BE_TABLE_SIZE (1 << CRC_BE_BITS) 24 #endif 25 26 static uint32_t crc32table_le[LE_TABLE_ROWS][256]; 27 static uint32_t crc32table_be[BE_TABLE_ROWS][256]; 28 static uint32_t crc32ctable_le[LE_TABLE_ROWS][256]; 29 30 /** 31 * crc32init_le() - allocate and initialize LE table data 32 * 33 * crc is the crc of the byte i; other entries are filled in based on the 34 * fact that crctable[i^j] = crctable[i] ^ crctable[j]. 35 * 36 */ 37 static void crc32init_le_generic(const uint32_t polynomial, 38 uint32_t (*tab)[256]) 39 { 40 unsigned i, j; 41 uint32_t crc = 1; 42 43 tab[0][0] = 0; 44 45 for (i = LE_TABLE_SIZE >> 1; i; i >>= 1) { 46 crc = (crc >> 1) ^ ((crc & 1) ? polynomial : 0); 47 for (j = 0; j < LE_TABLE_SIZE; j += 2 * i) 48 tab[0][i + j] = crc ^ tab[0][j]; 49 } 50 for (i = 0; i < LE_TABLE_SIZE; i++) { 51 crc = tab[0][i]; 52 for (j = 1; j < LE_TABLE_ROWS; j++) { 53 crc = tab[0][crc & 0xff] ^ (crc >> 8); 54 tab[j][i] = crc; 55 } 56 } 57 } 58 59 static void crc32init_le(void) 60 { 61 crc32init_le_generic(CRC32_POLY_LE, crc32table_le); 62 } 63 64 static void crc32cinit_le(void) 65 { 66 crc32init_le_generic(CRC32C_POLY_LE, crc32ctable_le); 67 } 68 69 /** 70 * crc32init_be() - allocate and initialize BE table data 71 */ 72 static void crc32init_be(void) 73 { 74 unsigned i, j; 75 uint32_t crc = 0x80000000; 76 77 crc32table_be[0][0] = 0; 78 79 for (i = 1; i < BE_TABLE_SIZE; i <<= 1) { 80 crc = (crc << 1) ^ ((crc & 0x80000000) ? CRC32_POLY_BE : 0); 81 for (j = 0; j < i; j++) 82 crc32table_be[0][i + j] = crc ^ crc32table_be[0][j]; 83 } 84 for (i = 0; i < BE_TABLE_SIZE; i++) { 85 crc = crc32table_be[0][i]; 86 for (j = 1; j < BE_TABLE_ROWS; j++) { 87 crc = crc32table_be[0][(crc >> 24) & 0xff] ^ (crc << 8); 88 crc32table_be[j][i] = crc; 89 } 90 } 91 } 92 93 static void output_table(uint32_t (*table)[256], int rows, int len, char *trans) 94 { 95 int i, j; 96 97 for (j = 0 ; j < rows; j++) { 98 printf("{"); 99 for (i = 0; i < len - 1; i++) { 100 if (i % ENTRIES_PER_LINE == 0) 101 printf("\n"); 102 printf("%s(0x%8.8xL), ", trans, table[j][i]); 103 } 104 printf("%s(0x%8.8xL)},\n", trans, table[j][len - 1]); 105 } 106 } 107 108 int main(int argc, char** argv) 109 { 110 printf("/* this file is generated - do not edit */\n\n"); 111 112 if (CRC_LE_BITS > 1) { 113 crc32init_le(); 114 printf("static const u32 ____cacheline_aligned " 115 "crc32table_le[%d][%d] = {", 116 LE_TABLE_ROWS, LE_TABLE_SIZE); 117 output_table(crc32table_le, LE_TABLE_ROWS, 118 LE_TABLE_SIZE, "tole"); 119 printf("};\n"); 120 } 121 122 if (CRC_BE_BITS > 1) { 123 crc32init_be(); 124 printf("static const u32 ____cacheline_aligned " 125 "crc32table_be[%d][%d] = {", 126 BE_TABLE_ROWS, BE_TABLE_SIZE); 127 output_table(crc32table_be, LE_TABLE_ROWS, 128 BE_TABLE_SIZE, "tobe"); 129 printf("};\n"); 130 } 131 if (CRC_LE_BITS > 1) { 132 crc32cinit_le(); 133 printf("static const u32 ____cacheline_aligned " 134 "crc32ctable_le[%d][%d] = {", 135 LE_TABLE_ROWS, LE_TABLE_SIZE); 136 output_table(crc32ctable_le, LE_TABLE_ROWS, 137 LE_TABLE_SIZE, "tole"); 138 printf("};\n"); 139 } 140 141 return 0; 142 } 143