A13 Recovery - How to boot

[thunder45]

Hi guys,
I have a Chuwi V17 tablet (7" Android 4.0 Tablet PC with Boxchip A13(RAM A8 1.2GHz)+TFT screen Manufacturer From Shenzhen China, V17, 7.0 inch Tablet PC OEM Product)
Although it has some nice specs, a good battery life and comes rooted (with busybox) out of the box, its performance is terrible. Before dumping it out, I would like to give it a try on other ROMs, and maybe port CM10.1 myself. I have already dumped its full NAND, which are:

cat /proc/partitions
major minor  #blocks  name
  93        0      16384 nanda -> Bootloader
  93        8      16384 nandb -> u-boot env
  93       16      32768 nandc -> boot (kernel)
  93       24     524288 nandd -> /system
  93       32    1048576 nande -> /data
  93       40      16384 nandf -> misc
  93       48      32768 nandg -> recovery
  93       56     262144 nandh -> /cache
  93       64     262144 nandi -> /databk (umount at boot)
  93       72    5554176 nandj -> (UDISK) /mnt/sdcard

I have unpacked the recovery partition. It seems to be perfect. Its ramdisk has the following entries:

$ ls -la
total 249
drwxr-xr-x+ 1 user group       0 mar 13 20:23 .
d---------+ 1 user group       0 mar 13 20:25 ..
drwxrwx--x+ 1 user group       0 mar 13 20:23 data
-rw-r--r--  1 user group    2001 mar 13 20:23 default.prop
drwxr-xr-x+ 1 user group       0 mar 13 20:23 dev
drwxr-xr-x+ 1 user group       0 mar 13 20:23 etc
-rwxr-x---  1 user group  102852 mar 13 20:23 init
-rwxr-x---  1 user group    1313 mar 13 20:23 init.rc
-rwxr-x---  1 user group 1536000 mar 13 20:23 initlogo.rle
drwxr-xr-x+ 1 user group       0 mar 13 20:23 proc
drwxr-xr-x+ 1 user group       0 mar 13 20:23 res
drwxr-x---+ 1 user group       0 mar 13 20:23 sbin
drwxr-xr-x+ 1 user group       0 mar 13 20:23 sys
drwxr-xr-x+ 1 user group       0 mar 13 20:23 system
drwxr-xr-x+ 1 user group       0 mar 13 20:23 tmp
-rw-r--r--  1 user group     272 mar 13 20:23 ueventd.goldfish.rc
-rw-r--r--  1 user group    3825 mar 13 20:23 ueventd.rc
-rw-r--r--  1 user group    1032 mar 13 20:23 ueventd.sun5i.rc


$ ls -la res/images/
total 166
drwxr-xr-x+ 1 user group     0 mar 13 20:23 .
drwxr-xr-x+ 1 user group     0 mar 13 20:23 ..
-rw-r--r--  1 user group 19306 mar 13 20:23 icon_error.png
-rw-r--r--  1 user group 25261 mar 13 20:23 icon_installing.png
-rw-r--r--  1 user group 10095 mar 13 20:23 icon_installing_overlay01.png
-rw-r--r--  1 user group  9990 mar 13 20:23 icon_installing_overlay02.png
-rw-r--r--  1 user group  9782 mar 13 20:23 icon_installing_overlay03.png
-rw-r--r--  1 user group  9817 mar 13 20:23 icon_installing_overlay04.png
-rw-r--r--  1 user group  9863 mar 13 20:23 icon_installing_overlay05.png
-rw-r--r--  1 user group  9944 mar 13 20:23 icon_installing_overlay06.png
-rw-r--r--  1 user group 10062 mar 13 20:23 icon_installing_overlay07.png
-rw-r--r--  1 user group   673 mar 13 20:23 indeterminate01.png
-rw-r--r--  1 user group   687 mar 13 20:23 indeterminate02.png
-rw-r--r--  1 user group   661 mar 13 20:23 indeterminate03.png
-rw-r--r--  1 user group   665 mar 13 20:23 indeterminate04.png
-rw-r--r--  1 user group   683 mar 13 20:23 indeterminate05.png
-rw-r--r--  1 user group   676 mar 13 20:23 indeterminate06.png
-rw-r--r--  1 user group   118 mar 13 20:23 progress_empty.png
-rw-r--r--  1 user group   404 mar 13 20:23 progress_fill.png

And I have compared the SHA1SUM of the Kernel image on both the recovery (nandG) and boot (nandC) partitions, and they are exactly the same:

$ sha1sum.exe ../dump/nandc.img-kernel.gz
c2601985049b90a107f36a86fe0d64660ab15410 *../dump/nandc.img-kernel.gz


$ sha1sum.exe ../dump/nandg.img-kernel.gz
c2601985049b90a107f36a86fe0d64660ab15410 *../dump/nandg.img-kernel.gz

So it looks all good, but I can`t get my tablet to boot into recovery. I tried all the tricks I could find:
- Hold the volume up will still off, plug the usb cable, and then turn it on
- Do the same as above with LiveSuit running
- Do the same as above with all other keys (not only volume up)
- adb reboot recovery

Does anybody know any other way? Would I have to flash an new boot loader so it can recognize the boot into recovery instructions?

By the way, my key mapping is:

key 102   HOME              WAKE
key 1     BACK              WAKE
key 28      MENU                 WAKE_DROPPED
key 115      VOLUME_UP
key 217      VOLUME_DOWN

Thank you in advance

 

[thunder45]

Hi guys,
Looks like the following made the trick:

adb shell "echo -n boot-recovery | busybox dd of=/dev/block/nandf count=1 conv=sync; sync; reboot"

I got that from Mateusz Krawczuk/WillingMagic at https://spideroak.com/browse/share/SamsungCallisto/manta_mid08


But the recovery is not as functional as I thought it would be. It just gets me to icon_error.png


And nothing works from ADB, as it simply doesn`t find "sh". Looks like it didn`t mount the partitions right. I then checked the *.rc files and noticed that they are much simpler then the ones at the boot partition.
So it seems this recovery partition is not complete.
I`ll start working on a new one then.

Regards

 

[vampirefo.]

And that is normal for a stock recovery, you need custom recovery like cwm.