[GUIDE] Help! My Transformer TF700 boots only to recovery!!!!

[droidbound]

This is a guide to get you out of a "forced reboot to recovery loop", meaning:
Whenever you try to boot the tablet it boots directly into your custom recovery. You cannot even boot into the bootloader and fastboot mode. This has worked on the TF201, TF300 and TF700.
It should work on the TF701 but AFAIK that has not been tested as of now.



This trick is for this ^^ very specific situation only.
DO NOT DO THIS WILLY-NILLY FOR A HOST OF OTHER REASONS

This trick is NOT for the following scenarios:
soft-bricking your tablet
experiencing a bootloop
experiencing a hung boot
not being able to boot the ROM
unrecoverable bootloader error
482 other scenarios I can't think of right now

Do I have to mention that I will not be responsible for whatever YOU do to YOUR tablet under any circumstances even when following this guide to the letter????

How you got into this pickle:
With a custom recovery installed, you performed a Factory Reset from Settings or used the Wipe Data option in the bootloader.

Why you are in this pickle:
You didn't read enough.
Specifically my Beginners Guide to Flashing and that big fat red warning at the end of it

A little technical explanation:
What happens if you use Wipe Data from the bootloader or do a Factory Reset from Settings with a custom recovery installed is this:
The bootloader writes a command to the misc partition calling the recovery to perform a wipe of /data and then reboots.
The bootloader is always stock Asus. The command it issues was written for the stock recovery which performs actions like wiping partitions (among a few other things) on a stock system. The custom recovery you installed doesn't quite "get" this command since it was written for the stock recovery.
Now every time you boot, the bootloader checks the misc partition (before doing anything else), finds the wipe data command, calls the stock recovery to perform it, your custom recovery boots but doesn't "get" it and just hangs, the wipe data command does not get erased from misc as it would if it was executed, the user reboots......rinse and repeat ad nauseam.

How you get out of this pickle
When your tablet is booted to recovery you have ADB access to it from your PC. If you did not set up ADB/fastboot on your PC prior to this, find somebody to give you a good dope-slap then head over here to find instructions: Beginners Guide to Flashing

• To get your tablet out of the loop you'll need this: https://www.androidfilehost.com/?fid=24572369242686911
• Extract the zip and put the bootit.ko into the same folder as your adb.exe
• With your tablet in recovery connect it to your PC via USB cable, then open a command prompt from within your adb folder and issue this command:

adb devices

You should get something like this:

C:\adb>adb devices
* daemon nor running. starting it now on port xxxx *
* daemon started successfully *
List of devices attached 
0123456789ABCDEF        recovery

Then issue the following commands

adb push bootit.ko /sdcard/
adb shell insmod /sdcard/bootit.ko

The tablet should reboot into the bootloader where you have fastboot access.
Now issue these commands:

fastboot devices
fastboot erase misc
fastboot reboot

You should now be able to boot into your ROM normally, boot back into recovery to wipe data, flash a rom - whatever.
From now on ONLY wipe and format partitions in recovery. Period.

We have bootit.ko thanks to the genius of @_that, member, developer and genius extraordinaire in the XDA forums.

[droidbound]

bootit.ko has been used successfully on the TF201, TF300 and TF700. It probably works on the TF701 but that is untested.

For that reason this guide has been duplicated in the respective device sections.

It may be a good idea to browse the other threads because the following discussion will be different in each thread.

TF201 thread: [GUIDE] Help! My Transformer TF201 boots only to recovery!!!!

TF300 thread: http://www.transformerforums.com/for...tml#post336080

[LetMeKnow]

Done.
http://www.transformerforums.com/for...-recovery.html

And right after writing this I found lj's guide on XDA describing the same thing....
But mine is prettier

I believe that misc partition boots before the initial script so the bootit.ko may not needed. In another word, you may not need to push the bootit.ko to your root directory. Just erase the misc partition should work. Maybe, we need some feedback from users running into this issue.. Just my two cents...

[droidbound]

I believe that misc partition boots before the initial script so the bootit.ko may not needed. In another word, you may not need to push the bootit.ko to your root directory. Just erase the misc partition should work. Maybe, we need some feedback from users running into this issue.. Just my two cents...

And how do you erase the misc partition if you cannot boot into fastboot?
Oh! Do you mean with a dd command from terminal in TWRP? What do you do in CWM which doesn't have a terminal?

[LetMeKnow]

And how do you erase the misc partition if you cannot boot into fastboot?
Oh! Do you mean with a dd command from terminal in TWRP? What do you do in CWM which doesn't have a terminal?

You are correct about cwm, haha. I was thinking about the booting process and not overall issues. I shut up from here...

[droidbound]

You are correct about cwm, haha. I was thinking about the booting process and not overall issues. I shut up from here...

@LetMeKnow: I moved these posts here - feel better not hijacking that other thread..

No, you're totally correct and your idea is interesting.
Yes, I believe misc is checked for any commands before even the bootloader menu boots. It could well be that _that released bootit.ko before we knew about the role of the misc partition in the boot sequence or that the BL dumps that call for the recovery to it if you use Wipe Data from the BL.
So if you have a recovery with a build-in terminal as TWRP does, it should be possible to wipe the misc partition from terminal, right?
Then you would only need bootit.ko if you didn't have a terminal available in recovery.
Now the question is: Do I want to test it???

misc is mmcblk0p3 right?
So the command would be

dd if=/dev/zero of=/dev/block/mmcblk0p3 bs=64 count=1

Do you concur?

[LetMeKnow]

@LetMeKnow: I moved these posts here - feel better not hijacking that other thread..

No, you're totally correct and your idea is interesting.
Yes, I believe misc is checked for any commands before even the bootloader menu boots. It could well be that _that released bootit.ko before we knew about the role of the misc partition in the boot sequence or that the BL dumps that call for the recovery to it if you use Wipe Data from the BL.
So if you have a recovery with a build-in terminal as TWRP does, it should be possible to wipe the misc partition from terminal, right?
Then you would only need bootit.ko if you didn't have a terminal available in recovery.
Now the question is: Do I want to test it???

misc is mmcblk0p3 right?
So the command would be

dd if=/dev/zero of=/dev/block/mmcblk0p3 bs=64 count=1

Do you concur?

I don't have the tf700 at the moment. I will test it for you when I grab it from my nephew, hehe. I believe the misc partition on the tf700 is just a temp partition to keep the working in progress so it will continue on the next boot. However, other devices have more stuffs on it and if you erase it, it will not boot at all unless copy back all the files on it. It will be a fun experiment on this matter, haha...

About the mmcblkp3, I could not remember if it is the misc or not. The bs=64 should be larger like 64k so you can write it faster.. That is all that I know and hope someone can chime so we can all learn...

[janner43]

@droidbound

Great thread & worthy of repetition so I have duplicated the first two posts in the thread into their own threads in the TF201 & TF300 Development areas. If they are not "stickies", feel free to make them so...

Great job!

[droidbound]

That command ^^ actually matches one I got from _that a while ago when I converted data to f2fs without having a compatible kernel installed and got the "encryption unsuccessful" error. He thought I was in a forced reboot to recovery loop, but I wasn't. So I never tried that command.
Here's a ls of my TF700 partitons:

C:\adb>adb shell
root@tf700t:/ # cat /proc/partitions
cat /proc/partitions
major minor  #blocks  name

 179        0   31039488 mmcblk0
 179        1     786432 mmcblk0p1
 179        2     438272 mmcblk0p2
 179        3       2048 mmcblk0p3
 179        4     835584 mmcblk0p4
 179        5       5120 mmcblk0p5
 179        6        512 mmcblk0p6
 179        7       5120 mmcblk0p7
 179        8   28924416 mmcblk0p8
 179       32       2048 mmcblk0boot1
 179       16       2048 mmcblk0boot0
 179       48   31260672 mmcblk1
 179       49   10129408 mmcblk1p1
 179       50   21127168 mmcblk1p2
root@tf700t:/ #

And going by this on github https://github.com/rabits/tf700/blob...tf700t_64G.txt
I would think mmcblk0p3 is misc.
I'm going to have to give this a shot one of these days. Right now I'm enjoying the Lollipop beta too much. Don't wanna purposely brick it just now

To anybody possibly coming to this thread for help:
The steps I posted in the OP absolutely work! This is just two nerds discussing a different solution to a solved problem

[droidbound]

@droidbound

Great thread & worthy of repetition so I have duplicated the first two posts in the thread into their own threads in the TF201 & TF300 Development areas. If they are not "stickies", feel free to make them so...

Great job!

Thanks! They're already stickied, so I could not exercise my (still new) superpowers