Shaojun Wang

Android "Factory data reset" on MX53 SMD -blog archive

Discussion created by Shaojun Wang Employee on Nov 14, 2011

 

Suppose booting from SD card, all Android images are already in SD.

 

1. In MX53 SMD, Linux Kernel will recognize emmc to mmcblk0, recognize SD to mmcblk1.  Because we are testing recovery in SD card, modify "device/fsl/imx53_smd/recovery.fstab" to mount to SD partition in recovery mode.

cat myandroid/device/fsl/imx53_smd/recovery.fstab

/system ext4 /dev/block/mmcblk1p2

/data ext4 /dev/block/mmcblk1p5

/cache ext4 /dev/block/mmcblk1p6

 

# UBI support is under below:

#/system ubifs /dev/ubi1_0

#/data ubifs /dev/ubi1_2

#/cache ubifs /dev/ubi1_1

 

/sdcard vfat /dev/block/mmcblk1p1

 

2. After select "Factory data reset" from Android UI, a file named as "command" will be create in cache partition. Cache partition is formatted to ext4, but u-boot only support ext2, so when creating cache partition, add "–O^extent" to back compatible to ext2.

mkfs.ext4 /dev/sdx6 -O ^extent -L cache

 

3. To do the factory data reset, by pressing “Settings -> Privacy -> Factory data reset” on Android UI, u-boot will detect a “command” file in recovery directory of cache partition, then bootup to recovery mode, erase data, and then reboot to normal mode.

The “Factory data reset” procedure is completed.

 

4. To enter recovery by u-boot command line,

setenv bootargs_android_recovery 'setenv bootargs ${bootargs} init=/init root=/dev/mmcblk1p4 rootfs=ext4 video=mxcdi1fb:RGB666,XGA ldb=di1 di1_primary 
setenv bootcmd_android_recovery 'run bootargs_android_recovery;mmc read 0 ${loadaddr} 0x800 0x2000;bootm'
run bootcmd_android_recovery

 

5. After see a robot and a triangle with exclamation mark inside, press usb keyboard F1, can go into text menu. This step is described in iMX Android user guide.

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