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1// SPDX-License-Identifier: GPL-2.02#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 49 10#if CRC_LE_BITS > 811# define LE_TABLE_ROWS (CRC_LE_BITS/8)12# define LE_TABLE_SIZE 25613#else14# define LE_TABLE_ROWS 115# define LE_TABLE_SIZE (1 << CRC_LE_BITS)16#endif17 18#if CRC_BE_BITS > 819# define BE_TABLE_ROWS (CRC_BE_BITS/8)20# define BE_TABLE_SIZE 25621#else22# define BE_TABLE_ROWS 123# define BE_TABLE_SIZE (1 << CRC_BE_BITS)24#endif25 26static uint32_t crc32table_le[LE_TABLE_ROWS][256];27static uint32_t crc32table_be[BE_TABLE_ROWS][256];28static uint32_t crc32ctable_le[LE_TABLE_ROWS][256];29 30/**31 * crc32init_le() - allocate and initialize LE table data32 *33 * crc is the crc of the byte i; other entries are filled in based on the34 * fact that crctable[i^j] = crctable[i] ^ crctable[j].35 *36 */37static 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 59static void crc32init_le(void)60{61 crc32init_le_generic(CRC32_POLY_LE, crc32table_le);62}63 64static 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 data71 */72static 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 93static 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 108int 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