AMDGPU not working on GCN 1.0 with kernel 5.9 and above

[Dukenukemx]

I have a Radeon HD 7850 and kernel 5.8 and bellow I can get AMDGPU to work but with 5.9 or higher I can't boot into the UI of Linux Mint 20. This was the command I used in grub along with updating grub to get AMDGPU instead of Radeon. Anybody know why?

GRUB_CMDLINE_LINUX=" radeon.si_support=0 radeon.cik_support=0 amdgpu.si_support=1 amdgpu.cik_support=1"

**EDIT**
Seems I'm not the only one with this problem.

https://forum.endeavouros.com/t/kernel-5-9-x-and-amdgpu-problem/10448/8

[funk_Farmer]

Any luck with this? I've been having similar problems trying to get a R7 370 working.

[Dukenukemx]

Still no luck with 5.11 Kernel. I tried using Xanmod. Best chance of getting this to work is using M-Bab / linux-kernel-amdgpu-binaries. So far it causes a page fault for me but I'm asking the developer for help.

[bridgman]

In the endeavorOS ticket the last post reported success with 5.10 non-zen kernels, but it wasn't clear if they were still having trouble with zen kernels.

[Dukenukemx]

In the endeavorOS ticket the last post reported success with 5.10 non-zen kernels, but it wasn't clear if they were still having trouble with zen kernels.

Yep, I posted there a few months ago asking about the issue. A Greek guy named jimmy213 had a similar issue and found that using the non-zen kernel worked. According to jimmy's last post, the 5.10 normal kernel and zen kernel both work on Arch based EndeavorOS. Whatever the problem is with GCN1.0 and AMDGPU seems unique to Ubuntu kernels. Gotta find a kernel that fixes whatever 5.9 and up have done to break it. Really sucks because even with kernel 5.8 I can't seem to play Doom Eternal and DXVK DX11 games. Dolphin using Vulkan will work find though.