p1022ds: get the env variable address

Get the environment variable address

Signed-off-by: Jerry Huang <Chang-Ming.Huang@freescale.com>

1 files changed, 45 insertions, 0 deletions

diff --git a/board/freescale/p1022ds/p1022ds.c b/board/freescale/p1022ds/p1022ds.c
index e6cfe421a7..6ea221dbd8 100644
--- a/board/freescale/p1022ds/p1022ds.c
+++ b/board/freescale/p1022ds/p1022ds.c
@@ -37,6 +37,8 @@
 #include <asm/fsl_law.h>
 #include <asm/mp.h>
 #include <netdev.h>
+#include <mmc.h>
+#include <malloc.h>
 
 #include "../../../drivers/block/fsl_sata.h"
 
@@ -509,3 +511,46 @@ void board_lmb_reserve(struct lmb *lmb)
 	cpu_mp_lmb_reserve(lmb);
 }
 #endif
+#if defined(CONFIG_MMC)
+/*
+ * The environment variables are written to just after the u-boot image
+ * on SDCard, so we must read the MBR to get the start address and code
+ * length of the u-boot image, then calculate the address of the env.
+ */
+#define ESDHC_BOOT_IMAGE_SIZE	0x48
+#define ESDHC_BOOT_IMAGE_ADDR	0x50
+
+int mmc_get_env_addr(int dev, u32 *env_addr)
+{
+	int ret;
+	u8 *tmp_buf;
+	u32 blklen, code_offset, code_len;
+	struct mmc *mmc = find_mmc_device(dev);
+
+	mmc_init(mmc);
+
+	blklen = mmc->read_bl_len;
+	tmp_buf = malloc(blklen);
+	if (!tmp_buf)
+		return 1;
+
+	/* read out the first block, get the config data information */
+	ret = mmc_read(mmc, 0, tmp_buf, blklen);
+	if (ret) {
+		free(tmp_buf);
+		return 1;
+	}
+
+	/* Get the Source Address, from offset 0x50 */
+	code_offset = *(u32 *)(tmp_buf + ESDHC_BOOT_IMAGE_ADDR);
+
+	/* Get the code size from offset 0x48 */
+	code_len = *(u32 *)(tmp_buf + ESDHC_BOOT_IMAGE_SIZE);
+
+	*env_addr = code_offset + code_len;
+
+	free(tmp_buf);
+
+	return 0;
+}
+#endif