blob: e4323181fc677cf6a9e1294fd56dbe29ead825c5 [file] [log] [blame]
Jerry Huang1ac63e42011-01-24 17:09:54 +00001/*
2 * Copyright 2011 Freescale Semiconductor, Inc.
3 *
4 * See file CREDITS for list of people who contributed to this
5 * project.
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License as
9 * published by the Free Software Foundation; either version 2 of
10 * the License, or (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
20 * MA 02111-1307 USA
21 */
22
23#include <common.h>
24#include <mmc.h>
25#include <malloc.h>
26
27/*
28 * The environment variables are written to just after the u-boot image
29 * on SDCard, so we must read the MBR to get the start address and code
30 * length of the u-boot image, then calculate the address of the env.
31 */
32#define ESDHC_BOOT_IMAGE_SIZE 0x48
33#define ESDHC_BOOT_IMAGE_ADDR 0x50
34
35int mmc_get_env_addr(struct mmc *mmc, u32 *env_addr)
36{
37 u8 *tmp_buf;
38 u32 blklen, code_offset, code_len, n;
39
40 blklen = mmc->read_bl_len;
41 tmp_buf = malloc(blklen);
42 if (!tmp_buf)
43 return 1;
44
45 /* read out the first block, get the config data information */
46 n = mmc->block_dev.block_read(mmc->block_dev.dev, 0, 1, tmp_buf);
47 if (!n) {
48 free(tmp_buf);
49 return 1;
50 }
51
52 /* Get the Source Address, from offset 0x50 */
53 code_offset = *(u32 *)(tmp_buf + ESDHC_BOOT_IMAGE_ADDR);
54
55 /* Get the code size from offset 0x48 */
56 code_len = *(u32 *)(tmp_buf + ESDHC_BOOT_IMAGE_SIZE);
57
58 *env_addr = code_offset + code_len;
59
60 free(tmp_buf);
61
62 return 0;
63}