imx:mx6slevk add spi nor boot support

Add spi nor boot support for mx6slevk board.

Signed-off-by: Peng Fan <Peng.Fan@freescale.com>
Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
diff --git a/include/configs/mx6slevk.h b/include/configs/mx6slevk.h
index e3e7f76..e6c4130 100644
--- a/include/configs/mx6slevk.h
+++ b/include/configs/mx6slevk.h
@@ -187,9 +187,20 @@
 /* FLASH and environment organization */
 #define CONFIG_SYS_NO_FLASH
 
-#define CONFIG_ENV_OFFSET		(6 * SZ_64K)
 #define CONFIG_ENV_SIZE			SZ_8K
+
+#if defined CONFIG_SYS_BOOT_SPINOR
+#define CONFIG_ENV_IS_IN_SPI_FLASH
+#define CONFIG_ENV_OFFSET               (768 * 1024)
+#define CONFIG_ENV_SECT_SIZE            (64 * 1024)
+#define CONFIG_ENV_SPI_BUS              CONFIG_SF_DEFAULT_BUS
+#define CONFIG_ENV_SPI_CS               CONFIG_SF_DEFAULT_CS
+#define CONFIG_ENV_SPI_MODE             CONFIG_SF_DEFAULT_MODE
+#define CONFIG_ENV_SPI_MAX_HZ           CONFIG_SF_DEFAULT_SPEED
+#else
+#define CONFIG_ENV_OFFSET		(6 * SZ_64K)
 #define CONFIG_ENV_IS_IN_MMC
+#endif
 
 #define CONFIG_OF_LIBFDT
 #define CONFIG_CMD_BOOTZ