mx53loco: Add support to dynamically choose between fdt use or not

The CONFIG_SYS_CBSIZE has been change to 512 to avoid runtime errors as:

,---[ Runtime error ]
| Hit any key to stop autoboot:  0
| MX53LOCO U-Boot > pri netboot
| netboot=echo Booting from net ...; run netargs; if test ...
| prefetch abort
| pc : [<20747368>]          lr : [<20747365>]
| sp : af566e20  ip : 00000000     fp : 00000000
| r10: 00000002  r9 : af6dfc28     r8 : af566f58
| r7 : af6dfc10  r6 : 00000001     r5 : 00000002  r4 : 74206669
| r3 : 00000000  r2 : 00000060     r1 : 00000020  r0 : 0000018e
| Flags: nZCv  IRQs off  FIQs off  Mode SVC_32
| Resetting CPU ...
|
| resetting ...
`---

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>

include/configs/mx53loco.h

@@ -119,24 +119,60 @@
 #define CONFIG_EXTRA_ENV_SETTINGS \
 	"script=boot.scr\0" \
 	"uimage=uImage\0" \
+	"fdt_file=imx53-qsb.dtb\0" \
+	"fdt_addr=0x71000000\0" \
+	"boot_fdt=try\0" \
+	"ip_dyn=yes\0" \
 	"mmcdev=0\0" \
 	"mmcpart=2\0" \
 	"mmcroot=/dev/mmcblk0p3 rw rootwait\0" \
-	"mmcargs=setenv bootargs console=ttymxc0,${baudrate} root=${mmcroot} " \
+	"mmcargs=setenv bootargs console=ttymxc0,${baudrate} root=${mmcroot}\0" \
 	"loadbootscript=" \
 		"fatload mmc ${mmcdev}:${mmcpart} ${loadaddr} ${script};\0" \
 	"bootscript=echo Running bootscript from mmc ...; " \
 		"source\0" \
 	"loaduimage=fatload mmc ${mmcdev}:${mmcpart} ${loadaddr} ${uimage}\0" \
+	"loadfdt=fatload mmc ${mmcdev}:${mmcpart} ${fdt_addr} ${fdt_file}\0" \
 	"mmcboot=echo Booting from mmc ...; " \
 		"run mmcargs; " \
-		"bootm\0" \
+		"if test ${boot_fdt} = yes || test ${boot_fdt} = try; then " \
+			"if run loadfdt; then " \
+				"bootm ${loadaddr} - ${fdt_addr}; " \
+			"else " \
+				"if test ${boot_fdt} = try; then " \
+					"bootm; " \
+				"else " \
+					"echo WARN: Cannot load the DT; " \
+				"fi; " \
+			"fi; " \
+		"else " \
+			"bootm; " \
+		"fi;\0" \
 	"netargs=setenv bootargs console=ttymxc0,${baudrate} " \
 		"root=/dev/nfs " \
 		"ip=dhcp nfsroot=${serverip}:${nfsroot},v3,tcp\0" \
 	"netboot=echo Booting from net ...; " \
 		"run netargs; " \
-		"dhcp ${uimage}; bootm\0" \
+		"if test ${ip_dyn} = yes; then " \
+			"setenv get_cmd dhcp; " \
+		"else " \
+			"setenv get_cmd tftp; " \
+		"fi; " \
+		"${get_cmd} ${uimage}; " \
+		"if test ${boot_fdt} = yes ||  test ${boot_fdt} = try; then " \
+			"if ${get_cmd} ${fdt_addr} ${fdt_file}; then " \
+				"bootm ${loadaddr} - ${fdt_addr}; " \
+			"else " \
+				"if test ${boot_fdt} = try; then " \
+					"bootm; " \
+				"else " \
+					"echo ERROR: Cannot load the DT; " \
+					"exit; " \
+				"fi; " \
+			"fi; " \
+		"else " \
+			"bootm; " \
+		"fi;\0"
 
 #define CONFIG_BOOTCOMMAND \
 	"mmc dev ${mmcdev}; if mmc rescan; then " \
@@ -157,7 +193,7 @@
 #define CONFIG_SYS_HUSH_PARSER		/* use "hush" command parser */
 #define CONFIG_SYS_PROMPT		"MX53LOCO U-Boot > "
 #define CONFIG_AUTO_COMPLETE
-#define CONFIG_SYS_CBSIZE		256	/* Console I/O Buffer Size */
+#define CONFIG_SYS_CBSIZE		512	/* Console I/O Buffer Size */
 
 /* Print Buffer Size */
 #define CONFIG_SYS_PBSIZE (CONFIG_SYS_CBSIZE + sizeof(CONFIG_SYS_PROMPT) + 16)