Add four main boot methods to developer build

include/configs/chromeos/tegra2/recovery.h

 /*
  * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef __configs_chromeos_tegra2_recovery_h__
 #define __configs_chromeos_tegra2_recovery_h__
 
 #include <configs/chromeos/recovery.h>
 #include <configs/chromeos/tegra2/common.h>
 
 #include <configs/chromeos/tegra2/parts/usb.h>
 
+/*
+ * Recovery mode tries to boot from all the sources in sequence. The boot
+ * source has a U-Boot script in it which contains the appropriate boot
+ * commands.
+ */
+#define CONFIG_EXTRA_ENV_SETTINGS_ARCH \
+        "scriptaddr=0x408000\0" \
+        "script_img=/u-boot/boot.scr.uimg\0" \
+        "mmc0_boot=setenv devnum 0; run mmc_boot;\0" \
+        "mmc1_boot=setenv devnum 1; run mmc_boot;\0" \
+        "usb0_boot=usb start 0; run usb_boot;\0" \
+        "usb1_boot=usb start 1; run usb_boot;\0" \
+        "scr_boot=fatload ${devtype} ${devnum}:c ${scriptaddr} ${script_img};"\
+                "source ${scriptaddr};" \
+                "read ${devtype} ${devnum}:${kernelpart} ${scriptaddr} 0 10;" \
+                "source ${scriptaddr};\0" \
+        "mmc_boot=mmc init ${devnum};" \
+                "setenv devtype mmc;" \
+                "setenv devname mmcblk${devnum}p;" \
+                "run scr_boot;\0" \
+        "usb_boot=setenv devtype usb;" \
+                "setenv devnum 0;" \
+                "setenv devname sda;" \
+                "run scr_boot;\0"
+
 #endif //__configs_chromeos_tegra2_recovery_h__