Primary Bootloader (before u-boot) in sysmoBTSv2
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/*
* crc.h -- CRC routines
*
* Copyright (C) 2008 Hugo Villeneuve <hugo@hugovil.com>
*
* Based on dv-boot, original copyright follows:
* Copyright (c) 2007 Sergey Kubushin <ksi@koi8.net>
*
* Based on TI DaVinci Flash and Boot Utilities, original copyright follows:
* Copyright 2008 Texas Instruments, Inc. <www.ti.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include <stdint.h>
#include <string.h> /* For size_t */
#define CRC_TABLE_ELEMENTS 256
#define DAVINCI_CRC_POLY 0x04C11DB7
static uint32_t crc32_table[CRC_TABLE_ELEMENTS];
static uint32_t
reflect_num(uint32_t in_val, uint32_t num)
{
uint32_t i;
uint32_t out_val = 0x0;
for (i = 1; i < (num + 1); i++) {
out_val |= (uint32_t)(((in_val & 0x1)) << (num - i));
in_val >>= 1;
}
return out_val;
}
/* Build a reflected CRC-32 table (for standard CRC-32 algorithm) */
void
crc32_dv_build_table(void)
{
uint32_t i, j, crc_accum;
for (i = 0; i < CRC_TABLE_ELEMENTS; i++) {
crc_accum = reflect_num(i, 8) << (32 - 8);
for (j = 0; j < 8; j++) {
if ((crc_accum & 0x80000000) != 0x00000000)
crc_accum = (crc_accum << 1) ^ DAVINCI_CRC_POLY;
else
crc_accum = (crc_accum << 1);
crc32_table[i] = reflect_num(crc_accum, 32);
}
}
}
/* Compute CRC32 checksum */
uint32_t
crc32_dv_compute(uint8_t *data, size_t size)
{
uint32_t crc32 = 0xFFFFFFFF;
while (size-- > 0)
crc32 = crc32_table[(crc32 ^ *data++) & 0xFF] ^ (crc32 >> 8);
return crc32;
}