[ROM][5.1.1] AOSP-5.1.1 / CM-12.1 for Lenovo a2109 (20160901)

[PJBrs]

Aaaaaaand...... AOSP!!!

aosp_kai-ota-eng-5.1.1-May_2016.pj.zip (md5: ee454f6b160278b2e147500b30ff4074)

Note that AOSP will write overwrite your recovery, and it is not rooted.

 

[stefano375]

wooooow, great job
i have installed aosp and opengapps ARM nano 5.1, system is very fast but I can't find play store, I have done something wrong?

 

[stefano375]

Solved by installing gapps posted by @joebine, now tablet is resurrected, great job

 

[PJBrs]

Finished first marshmallow build. Completely refuses to boot. If anyone can point me to a list of patches needed for kernel 3.1...

 

[joebine]

Hi PJBrs, I am running CM12.1 on one of my tablet and AOSP on the other and CM12.1 is a bit less stable then AOSP.

Did you try the new blobs with AOSP?

I am always available to try new things so let me know.

Envoyé de mon A2109A en utilisant Tapatalk

 

[PJBrs]

Hi PJBrs, I am running CM12.1 on one of my tablet and AOSP on the other and CM12.1 is a bit less stable then AOSP.

I strangely have the same impression. Really don't know why, must be in some of the cyanogenmod changes.

Did you try the new blobs with AOSP?

I am always available to try new things so let me know.

No, I didn't. It would make it even simpler to build AOSP, but it would remove the ability of video conferencing, which I think is quite an important feature for a tablet.

I suspect that the problem with the new blobs is that it requires a rather big 'hack' of the camera HAL. I've basically added all stock libraries as dependencies for the stock camera HAL, by binary hacking the references to dynamic libraries (e.g., libnvos.so -> libntos.so). The final step in this exercise is that it actually requires the old gralloc HAL to be present (I don't really know what gralloc means), and otherwise loading the camera HAL fails with a crash in NvGrLock (IIRC). The problem might reside in using two versions of gralloc concurrently. So if I'd be able to _only_ use the old NvGrLock function, and for the rest just the new blobs...

 

[DBlake]

Here's a snippit from Mozilla's wiki on Gralloc:

Gralloc is a type of shared memory that is also shared with the GPU. A Gralloc buffer can be written to directly by regular CPU code, but can also be used as an OpenGL texture.

Also, I found a project that ported AOSP Marshmallow to Grouper. Maybe this would be helpful for you: Android M on Nexus 7 2012 - Dmitry Grinberg

 

[PJBrs]

Here's a snippit from Mozilla's wiki on Gralloc:



Also, I found a project that ported AOSP Marshmallow to Grouper. Maybe this would be helpful for you: Android M on Nexus 7 2012 - Dmitry Grinberg

Thanks, I've browsed the info. I'm a bit hesitant - there's one big kernel patch that supposedly adds the marshmallow requirements to kernel 3.1. If we'd have 3.4, it'd be no problem at all, so... I'm betting on two horses right now - I'll pick up that patch later, but I've also picked up the kernel work again, just compiled our kernel on top of nvidia's latest 3.1 version, then I'm going to do some cleaning up in the board files, and then I'm going to see whether we can port lenovo's changes to 3.4. The point is, Google is still maintaining a 3.4 branch.

 

[nni123]

Aaaaaaand...... AOSP!!!

aosp_kai-ota-eng-5.1.1-May_2016.pj.zip (md5: ee454f6b160278b2e147500b30ff4074)

Note that AOSP will write overwrite your recovery, and it is not rooted.

You saved the tablet from going out of business.

Installed AOSP from 4.1.1 (3 years old) without any issue.

Thank you so much

 

[PJBrs]

New build for cm-12.1, with the June security fixes, and a quite different kernel, with the latest 3.1 sources for our tablet. I'm still cleaning up, still haven't been able to successfully boot 3.4. Might give up on that. Also working on AOSP-5.1, but some compile errors...

cm-12.1-20160617-UNOFFICIAL-kai.zip (md5: f8c61545becf45bc98e46feb20ec2cb8)

 

[scissors99]

You saved the tablet from going out of business.

Installed AOSP from 4.1.1 (3 years old) without any issue.

Thank you so much

Firstly, PJBrs , I am in awe of what you and others have done.
To the point.
I have been reading this thread for over six months, trying to get the guts up to risk my a2109 stock 4.1.1
but it's getting to the point where so many bits of software require 4.2 upwards.

The problem is I am an average user of PCs from c64 to atari st right through windows 3 to present w10
I am no dummy, but flashing android is new to me.

If I have understood, the steps are basically
1)unlock lenovo with lenovos own tool
2)install CW mod (for blobs?)
3)install ASOP

I know it's a massive ask, but could someone post a step by step, with file links for your average bloke.
I understand it's not risk free, but if such a guide was available I would give it a go.

Many Thanks

 

[PJBrs]

If I have understood, the steps are basically
1)unlock lenovo with lenovos own tool
2)install CW mod (for blobs?)
3)install ASOP

These are basically the steps to take, yes.

Regarding 1 - I just used a fastboot version I got somewhere, perhaps self-compiled, I don't remember, for linux. The command should be sth like:

fastboot -i 0x17ef oem unlock

Regarding 2 - You need a relatively new cwm or twrp recovery image. The reason you need to use recovery at all is that we need recovery to install android from an update package, and that's how I've distributed the lollipop builds. The reason you need one of the latest builds is that kitkat and lollipop update packages expect certain kernel configurations that weren't present before.

Regarding 3 - Yes, *and* if you like, also install google apps (gapps), such as opengapps. Be sure to pick one of the smaller sized packages, (nano, I believe), otherwise it won't fit. And be sure to install opengapps right after you flashed AOSP or cm-11, otherwise some google apps might misbehave. Good luck, and let us know whether it worked!

 

[joebine]

I know it's a massive ask, but could someone post a step by step, with file links for your average bloke.
I understand it's not risk free, but if such a guide was available I would give it a go.

Many Thanks

Ok here a recipe to do the job right on a Windows system:

1- Download Letools from Lenovo: LeTools Download
2- You have to root your tablet. Instructions here:
Development: A2109 Root - Page 2 - Lenovo Community
** Look for the post of mcl630 in the middle of the page. **
3- Then you have to install CWMrecovery. Instructions here:
A2109 - Clockworkmod Recovery and Root - Lenovo Community
I suggest that you install the CWMrecovery posted by @PJBrs here cwm-6.0.5.1-20160214-UNOFFICIAL-kai.img
4- Copy the ROM you want to install and the gapps to your SDcard
5- Reboot to recovery (when tablet is off, push the sounds up button while opening the tablet)
6- Install the ROM in recovery.
7- Just after the ROM is install, do not reboot and install in recovery the gapps you had downloaded from here:
The Open GApps Project

First boot is very long so by patient,

Your done

 

[scissors99]

Brilliant! Thanks.
I'm off an annual leave ATM, but will give that a crack when I get back.

 

[jam97]

Is it ok to unlock boot loader, flash cm recovery and flash cm12 rom then relock boot loader again?

Sent from my SM-N910P using Tapatalk