projects / J-u-boot.git / blame
| Commit | Line | Data |
|---|---|---|
| 83d290c5 | 1 | // SPDX-License-Identifier: GPL-2.0+ |
| abbc67ee CM |
2 | /* |
| 3 | * Copyright 2012 Freescale Semiconductor, Inc. | |
| 4 | * | |
| 5 | * Cleaned up and refactored by Charles Manning. | |
| abbc67ee CM |
6 | */ |
| 7 | #include "pblimage.h" | |
| 3db71108 | 8 | #include <u-boot/crc.h> |
| abbc67ee CM |
9 | |
| 10 | static uint32_t crc_table[256]; | |
| 11 | static int crc_table_valid; | |
| 12 | ||
| 13 | static void make_crc_table(void) | |
| 14 | { | |
| 15 | uint32_t mask; | |
| 16 | int i, j; | |
| 17 | uint32_t poly; /* polynomial exclusive-or pattern */ | |
| 18 | ||
| 19 | if (crc_table_valid) | |
| 20 | return; | |
| 21 | ||
| 22 | /* | |
| 23 | * the polynomial used by PBL is 1 + x1 + x2 + x4 + x5 + x7 + x8 + x10 | |
| 24 | * + x11 + x12 + x16 + x22 + x23 + x26 + x32. | |
| 25 | */ | |
| 26 | poly = 0x04c11db7; | |
| 27 | ||
| 28 | for (i = 0; i < 256; i++) { | |
| 29 | mask = i << 24; | |
| 30 | for (j = 0; j < 8; j++) { | |
| 31 | if (mask & 0x80000000) | |
| 32 | mask = (mask << 1) ^ poly; | |
| 33 | else | |
| 34 | mask <<= 1; | |
| 35 | } | |
| 36 | crc_table[i] = mask; | |
| 37 | } | |
| 38 | ||
| 39 | crc_table_valid = 1; | |
| 40 | } | |
| 41 | ||
| 42 | uint32_t pbl_crc32(uint32_t in_crc, const char *buf, uint32_t len) | |
| 43 | { | |
| 44 | uint32_t crc32_val; | |
| 45 | int i; | |
| 46 | ||
| 47 | make_crc_table(); | |
| 48 | ||
| 49 | crc32_val = ~in_crc; | |
| 50 | ||
| 51 | for (i = 0; i < len; i++) | |
| 52 | crc32_val = (crc32_val << 8) ^ | |
| 53 | crc_table[(crc32_val >> 24) ^ (*buf++ & 0xff)]; | |
| 54 | ||
| 55 | return crc32_val; | |
| 56 | } |