Root [SOLUTION]Killing the A75 Bricker Devil

[varun.chitre15]

I almost took over full round of A75 forum and reviewed the bricking cases
So after the elongated thinking I have finally investigated the culprit of bricking

So the actual bricker devil is UB-2 and Gionee ROMs(no criticism )
Many of the A75 users were using Ub-2 and some were on gionee ROM after which they attempted to flash recovery and they bricked the phone

Why they bricked and how it all happened?
Well, Gionee ROM's kernel is overclocked and it is different than that of Stock kernel by micromax
As I have used mmx kernel in the recovery and the kernel mismatch occured and BOOMzzz... they bricked it


What should we users having bricked A75s should do?
Now straight forward visit the service center and get it repaired/replaced


Is it like Gionee people have to move to MMX ROM to get recovery?

No it isn't. I am going to release a recovery with gionee kernel which Gionee people can use

Is it safe to flash Gionee ROM using the current recovery which is based on MMX kernel?
No it is not safe!!! never attempt this if you want your device alive



Now I think it is safe to reopen all my projects and continue the development
Guys please follow the instructions which I always give while releasing any stuff
I already mentioned to flash recovery with UB-1


In the above sentences I used Gionee ROM is unsafe with current recovery but I don't know how Gionee ROM came
Can anyone tell me whether it contained only system.img or system.img & boot.img

Surely this recovery is dangerous for UB-2 users but not sure about Gionee ROM

 

[ninadchaudhari]

Simple stuff :

Like the UB-2 project already says Do not use it ! as it still contains a few bugs
still i wonder why ppl tried with Ub-2 with the recovery !!!!

Conclusion :
Leave Ub-2 alone
or use the recovery installer ! may be that helps

Spoiler

Really sorry as i cannot keep my promise
But really helpless !
coming here for a few minutes and giving hours for the code is different

 

[kumar abhishek]

Ok I was a UB-1 user . I bricked my A75 . It contrdicts with wt u said!!!
But I think main problem is due to overclock app I had overclocked my A75 may be due to this there was change in kernel. So I think we should ask those who have overclocked through app and got bricked or may be due to both app and UB-2 there is change in kernel and it leads to brick!! hope I am not wrong

 

[varun.chitre15]

Lol....do you mean you overclocked on stock mmx kernel?
Remember, u might have flashed new boot.img of Gionee ROM or UB-2 or any other
I wonder how you can overclock by using just a app lol....
Anyways it is surely caused due to altering in the kernel

 

[ninadchaudhari]

Lol....do you mean you overclocked on stock mmx kernel?
Remember, u might have flashed new boot.img of Gionee ROM or UB-2 or any other
I wonder how you can overclock by using just a app lol....
Anyways it is surely caused due to altering in the kernel

the mtk app

 

[Amarghy]

Yup yup. Even i used the mtk app (developed by xda) to underclock + undervoltage my cpu. Result was almost quadrupling of battery backup btw i dont think that the app was to blame....as it was a boot app + flashing deletes it + unless u have reached the launcher stage, the app wont initiate. I think the recovery needs some fine tuning
p.s- correct me if i am wrong, guys

 

[ANOOPPA]

Yup yup. Even i used the mtk app (developed by xda) to underclock + undervoltage my cpu. Result was almost quadrupling of battery backup btw i dont think that the app was to blame....as it was a boot app + flashing deletes it + unless u have reached the launcher stage, the app wont initiate. I think the recovery needs some fine tuning
p.s- correct me if i am wrong, guys

+1
Overclocking for MTK chips works in different manner. It is overclocked by changing PLL value's through engineering mode ( APP is just a GUI to do this ). So I dont think kernel difference will cause this kind of issue. This is clearly a scenario where initial FW ( loaders ) are not working.

There is a possibility I can think off.

There are couple of scatter.txt flying across the forum. Change in NAND flash partition is a bit tricky . Block , sector size's need to be defined after considering specific flash chip data sheet . OR else there is a possibility that it may corrupt entire flash chip . This may cause our Pre-loader ( and / or ) boot.img to get corrupted. ( I believe preloader resides in NAND ) .There is a high possibility that device will not even respond if boot.img is corrupted ( fw for USB detection will be in boot.img )

One think we can do is , compare scatter.txt files of bricked folks.


Other thing I could recommend is , If anybody try to flash recovery , should also flash boot.img along with.


Thanks
Anoop

 

[EverWin]

Hi guys,
i was using UB-A75-1 by ninadchaudhari (Excellet Work), i did factory reset a day before flashing cracked Recovery image. It worked without any problem.

I don't think their is any connection btw System image & recovery image during Flashing images, b'cos in past i did flash wrong version of boot.img & Recovery.img. Phone always hangs during boot then i switch back to original.

People who bricked their phone must have selected incorrect Micromax A75 Android scatter file before Flashing. I always create new directory for every new Flash, also make shur battery is charged USB is properly plugged-in no loose contacts and correct drivers are installed.

 

[saivignesh]

@varun this what I am tellinga for last 2 days
flashing that recovery.img with all gionee files sends my phone to heaven

anyway flashing just system.img from gionee rom doesn't create any problem for me
@varun for your info gionee rom contains many files boot recovery and 5 more files
but as I said using system.img of gionee rom doesnt creates problem

boot.img of gionee rom causes problem coz I always used modded boot.img provided by you coupled with system.img of gionee
doesn't create any problem at all

 

[varun.chitre15]

Here is the unbricking guide for A75 by pkotenetwork
I have stickied it
Unbricking guide

 

[shreymehrotra]

So the actual bricker devil is UB-2 and Gionee ROMs(no criticism )
Many of the A75 users were using Ub-2 and some were on gionee ROM after which they attempted to flash recovery and they bricked the phone

Why they bricked and how it all happened?
Well, Gionee ROM's kernel is overclocked and it is different than that of Stock kernel by micromax
As I have used mmx kernel in the recovery and the kernel mismatch occured and BOOMzzz... they bricked it

Nice work Varun and thanks for spending time
What my case was that i was usin UB1 but was not able to factory reset so i again flashed it with UB1 only(am damn sure about it coz i didn't downloaded anything and used the UB1 files that i already had)... After that i flashed CWM and went to recovery mode and after final restart it was bricked... Anyways this was my scenario

BTW good work and keep it up :thumbup:

 

[kumar abhishek]

Nice work Varun and thanks for spending time
What my case was that i was usin UB1 but was not able to factory reset so i again flashed it with UB1 only(am damn sure about it coz i didn't downloaded anything and used the UB1 files that i already had)... After that i flashed CWM and went to recovery mode and after final restart it was bricked... Anyways this was my scenario

BTW good work and keep it up :thumbup:

Did u use overclock app in UB-1?

 

[gta]

set-cpu doesn't work on mtk chips i wonder why !
guess they have overclocking enabled on kernel already !