uboot/board/gdsys/p1022/sdhc_boot.c
<<
>>
Prefs
   1/*
   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, int copy, 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, 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}
  64