mx28evk: Introduce a new target for saving env vars to NAND

Introduce 'mx28evk_nand' target for saving environment variables into NAND.

The mx28evk board does not come with a NAND flash populated from the
factory. It comes with an empty slot (U23), which allows the insertion of a
48-pin TSOP flash device.

Tested with a K9LBG08U0D.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Reviewed-by: NOtavio Salvador <otavio@ossystems.com.br>

boards.cfg

@@ -196,7 +196,8 @@ mx23_olinuxino               arm         arm926ejs   mx23_olinuxino      olimex
 apx4devkit                   arm         arm926ejs   apx4devkit          bluegiga       mxs		apx4devkit
 mx23evk                      arm         arm926ejs   mx23evk             freescale      mxs		mx23evk
 m28evk                       arm         arm926ejs   m28evk              denx           mxs		m28evk
-mx28evk                      arm         arm926ejs   mx28evk             freescale      mxs		mx28evk
+mx28evk                      arm         arm926ejs   mx28evk             freescale      mxs		mx28evk:ENV_IS_IN_MMC
+mx28evk_nand                 arm         arm926ejs   mx28evk             freescale      mxs		mx28evk:ENV_IS_IN_NAND
 sc_sps_1                     arm         arm926ejs   sc_sps_1            schulercontrol mxs
 nhk8815                      arm         arm926ejs   nhk8815             st             nomadik
 nhk8815_onenand              arm         arm926ejs   nhk8815             st             nomadik       nhk8815:BOOT_ONENAND

doc/README.mx28evk

@@ -23,6 +23,24 @@ To boot MX28EVK from an SD card, set the boot mode DIP switches as:
    * VDD 5V: To the left (off)
    * Hold Button: Down (off)
 
+
+Environment Storage
+-------------------
+
+There are two targets for mx28evk:
+
+"make mx28evk_config"		- store enviroment variables into MMC
+
+or
+
+"make mx28evk_nand_config"	- store enviroment variables into NAND flash
+
+Choose the target accordingly.
+
+Note: The mx28evk board does not come with a NAND flash populated from the
+factory. It comes with an empty slot (U23), which allows the insertion of a
+48-pin TSOP flash device.
+
 Follow the instructions from doc/README.mx28_common to generate a bootable SD
 card.
 

include/configs/mx28evk.h

@@ -62,6 +62,7 @@
 #define CONFIG_CMD_SPI
 #define CONFIG_CMD_USB
 #define CONFIG_CMD_BOOTZ
+#define CONFIG_CMD_NAND
 
 /* Memory configurations */
 #define CONFIG_NR_DRAM_BANKS		1		/* 1 bank of DRAM */
@@ -115,7 +116,6 @@
 #define CONFIG_APBH_DMA
 
 /* MMC Driver */
-#define CONFIG_ENV_IS_IN_MMC
 #ifdef CONFIG_ENV_IS_IN_MMC
  #define CONFIG_ENV_OFFSET	(256 * 1024)
  #define CONFIG_ENV_SIZE	(16 * 1024)
@@ -130,11 +130,40 @@
 #endif
 
 /* NAND Driver */
+#define CONFIG_ENV_SIZE			(16 * 1024)
 #ifdef CONFIG_CMD_NAND
 #define CONFIG_NAND_MXS
 #define CONFIG_SYS_MAX_NAND_DEVICE	1
 #define CONFIG_SYS_NAND_BASE		0x60000000
 #define CONFIG_SYS_NAND_5_ADDR_CYCLE
+
+/* Environment is in NAND */
+#define CONFIG_ENV_SIZE_REDUND		CONFIG_ENV_SIZE
+#define CONFIG_ENV_SECT_SIZE		(128 * 1024)
+#define CONFIG_ENV_RANGE		(512 * 1024)
+#ifndef CONFIG_ENV_OFFSET
+#define CONFIG_ENV_OFFSET		0x300000
+#endif
+#define CONFIG_ENV_OFFSET_REDUND	\
+		(CONFIG_ENV_OFFSET + CONFIG_ENV_RANGE)
+
+#define CONFIG_CMD_UBI
+#define CONFIG_CMD_UBIFS
+#define CONFIG_CMD_MTDPARTS
+#define CONFIG_RBTREE
+#define CONFIG_LZO
+#define CONFIG_MTD_DEVICE
+#define CONFIG_MTD_PARTITIONS
+#define MTDIDS_DEFAULT			"nand0=gpmi-nand"
+#define MTDPARTS_DEFAULT			\
+	"mtdparts=gpmi-nand:"			\
+		"3m(bootloader)ro,"		\
+		"512k(environment),"		\
+		"512k(redundant-environment),"	\
+		"4m(kernel),"			\
+		"128k(fdt),"			\
+		"8m(ramdisk),"			\
+		"-(filesystem)"
 #endif
 
 /* Ethernet on SOC (FEC) */