ARM: at91: sama5: add support for CONFIG_ENV_IS_IN_MMC

If defined CONFIG_ENV_IS_IN_MMC, then u-boot environment is saved in
mmc's raw sectors. Otherwise, u-boot environment is saved as a file:
uboot.env.

Signed-off-by: Josh Wu <josh.wu@atmel.com>
Reviewed-by: Bo Shen <voice.shen@gmail.com>

include/configs/at91-sama5_common.h

@@ -53,6 +53,13 @@
 #define CONFIG_CMD_DHCP
 
 #ifdef CONFIG_SYS_USE_MMC
+
+#ifdef CONFIG_ENV_IS_IN_MMC
+/* Use raw reserved sectors to save environment */
+#define CONFIG_ENV_OFFSET		0x2000
+#define CONFIG_ENV_SIZE			0x1000
+#define CONFIG_SYS_MMC_ENV_DEV		0
+#else
 /* u-boot env in sd/mmc card */
 #define CONFIG_ENV_IS_IN_FAT
 #define CONFIG_FAT_WRITE
@@ -60,6 +67,7 @@
 #define FAT_ENV_DEVICE_AND_PART	"0"
 #define FAT_ENV_FILE		"uboot.env"
 #define CONFIG_ENV_SIZE		0x4000
+#endif
 
 #define CONFIG_BOOTCOMMAND	"if test ! -n ${dtb_name}; then "	\
 				    "setenv dtb_name at91-${board_name}.dtb; " \