Black Screen on Tianma Display, Poco F1

[Gyurma1988]

If i flash a Tianma Boot image, i have a black screen. With EBBG boot image i have screen, but without touch.

My Poco has a Tianma Panel.

[Shubhamvis98]

Hi @Gyurma1988, On first boot the Droid juicer extracts the firmwares from vendor partitions. If the firmwares are missing the touch panel won't work. Here's the workaround: Try to reflash the rootfs and tianma boot.img or Repack the tianma boot.img with firmwares and try to boot again.

Sometimes you'll see black screen but try to poweroff and then poweron. We also face this issue sometimes but it works fine most of the time.

[Gyurma1988]

Hi, thanks for quick response.

I reflashed the boot and rootfs, but nothing.

I turned the screen off and on, but some error.

How can i repack the tianma boot.img with firmwares?

[Shubhamvis98]

First, you have to extract/copy split firmware files from vendor/modem partitions then use pilsquasher to merge and create mbn files. Then unpack boot.img and place the mbn files in ramdisk and repack. You can use AIK from my repository to unpack/repack the boot.img

[Gyurma1988]

I'm afraid this is a bit over my head. I'm just a regular user, not a programmer. Thank you for trying to help me out.

[Shubhamvis98]

Have you tried mobian? Check if mobian working or not.

[Shubhamvis98]

I'm afraid this is a bit over my head. I'm just a regular user, not a programmer. Thank you for trying to help me out.

Yes, that's a time consuming task. Droid-juicer service is doing this stuff at first boot. Try flashing mobian first. If it's working then kali should work as well. Or I'll check with someone who has tianma variant.

[Gyurma1988]

I tried Mobian, but I'm still having the same problem.

[Shubhamvis98]

Them maybe you're doing something wrong. Can you show me the output of cat /proc/cmdline from android os.

[Gyurma1988]

Sure

[Shubhamvis98]

It's tianma. Not sure then what the exact issue. I'll let you know if I get someone with tianma variant.

[Gyurma1988]

Ok, thank you very much.

[Gyurma1988]

Can you apply this patch to your build?

https://lwn.net/ml/linux-kernel/20201028221302.66583-1-kholk11@gmail.com/

It's from Postmarketos os.

[Gyurma1988]