GPU crash on initialisation on Wexler tab 7t

[mittorn]

GPU seem to crash while initialising android surfaceflinger. Is it affected on other devices?

[leyarx]

Yes! The kernel works very buggy. You could try to use compiled kernel https://github.com/leyarx/android_kernel_viewsonic_n710/releases/download/v0.1/boot-v0.1.img with TWRP or CWM. Only in this combination it works a bit. There is some problem with "scaling_governor". You could try to comment out lines related to governor in "init. .rc" file.

[mittorn]

It works with my gentoo root from Allwinner A10 (by specifing root option), but I could not get any input device (except of tablet buttons) get to work to debug it. Do you know how is built board configuration on tegra? Where is stored gpio/pin configuration? DT is supported, but is not used. As I understand, cpufreq and dvfs is broken, but does gpu driver work?

[leyarx]

Here is UART pins for ViewSonic N710. For Wexler Tab 7t they are the same "RX(TP56), TX(TP54)". I used them for debug.

[mittorn]

Thank you. I don't want to disassemble device now. Is there any way to configure uart on different port (for example, on sunxi devices uart can be made with microsd breakout)? Or android ram console (as i can map /dev/mem, i can access it from any kernel if there is free nvram)? Wexler provided source code for kernel, qc750_defconfig is same as in stock (/proc/config.gz), but kernel compiled from source wouldn't boot for some unknown reason, it hangs on fastboot screen.

[mittorn]

Disabling cpufreq solved screen noise problem, now kernel crashes in fbcon code when surfaceflinger starting.

[leyarx]

Ok I have never thought about reconfiguring UART on different port. But I think it's possible. Maybe this file could help you somehow. https://drive.google.com/file/d/0B4ZO4jLECnw8enB2UGo5U09rSXM/view?usp=sharing .About nvram I think yes, it's possible to erase recovery and use it as free space. You could try to enable framebuffer console in Wexler source code. I have not tried wexler's kernel source code yet.

[mittorn]

I tried to use framebuffer console, it does not work (i think it crashed before framebuffer initialisation). I will try to find some register (like rtc or led), that can be triggered at very early kernel initialisation to detect where kernel crashes. Thank you very much for t30l datasheet.

[mittorn]

/proc/kmsg when trying to start surfaceflinger: http://pastebin.com/fUJzNFy5

[mittorn]

n710 kernel does not crash when fbcon disabled, but surfaceflinger exits with sisgegv. I think that android is incompatible with kernel driver.

[leyarx]

Maybe there is a problem with nVidia proprietary files on your device. They are not compatible with Kernel. Try to replace those files from another device http://pastebin.com/dtEkEAMW . I have almost the same problem but there is a combination which works. Try those files from Nexus 7 or some ASUS devices.

2015-02-25 8:49 GMT+02:00 mittorn notifications@github.com:

/proc/kmsg when trying to start surfaceflinger: http://pastebin.com/fUJzNFy5

— Reply to this email directly or view it on GitHub https://github.com/leyarx/android_kernel_viewsonic_n710/issues/1#issuecomment-75913899 .

[leyarx]

But it is very strange that fbcon doesn't work.

[mittorn]

It conflicts with fbcon because android's blob does not switch VT to graphics mode (like does it X for example). I think it's possible to make workaround in kernel or find other android driver.

[mittorn]

grouper has different library names. gralloc.tegra.so v.s gralloc.tegra3.so. Or it will work if i replace all libraries?

[leyarx]

I really don't remember, try to rename them. But I think it's necessary to replace all of them.

[mittorn]

Suspend does not work too.

[mittorn]

Device turns off on egl initialisation when using blobs from grouper.

[leyarx]

Which version of android do you use? Could you please give me the link to your firmware and grouper blobs? I'll try to reproduce the bug.

2015-03-15 16:35 GMT+02:00 mittorn notifications@github.com:

Device turns off on egl initialisation when using blobs from grouper.

— Reply to this email directly or view it on GitHub https://github.com/leyarx/android_kernel_viewsonic_n710/issues/1#issuecomment-81044329 .

[mittorn]

http://4pda.ru/forum/index.php?s=&showtopic=426283&view=findpost&p=26180357 https://developers.google.com/android/nexus/drivers#grouperjdq39

[mittorn]

Wexler kernel boot's after enabling TRUSTED_FOUNDATIONS, all hardware seems to work

[leyarx]

Yep, I'm also expect the problem. EGL is restarting every minute or less. That nice news, I don't tried to compile Wexler kernel yet, just download the sources and dig a bit in them.

2015-03-17 19:05 GMT+02:00 mittorn notifications@github.com:

Wexler kernel boot's after enabling TRUSTED_FOUNDATIONS, all hardware seems to work

— Reply to this email directly or view it on GitHub https://github.com/leyarx/android_kernel_viewsonic_n710/issues/1#issuecomment-82483414 .

[mittorn]

I think that wexler's kernel should work on N710 too. You can also look to nabi2 kernel, it seems to be similar. However it does not boot on my tablet, you would be able to boot it with serial console.

[leyarx]

I believe so. I'll try to compile, and boot it on my tablet.

2015-03-20 16:45 GMT+02:00 mittorn notifications@github.com:

I think that wexler's kernel should work on N710 too. You can also look to nabi2 kernel, it seems to be similar. However it does not boot on my tablet, you would be able to boot it with serial console.

— Reply to this email directly or view it on GitHub https://github.com/leyarx/android_kernel_viewsonic_n710/issues/1#issuecomment-84034769 .