Re: [PATCH] drm/amd/amdgpu: add firmware file fallback for APU VBIOS discovery

[Alex Deucher]

On Mon, Nov 2, 2026 at 3:07 AM Arnaud BERTRAND <arnaud078@xxxxxxxxx> wrote:
>
> Hello,
>
> I have two dGPUs : a Radeon RX 6800
> XT and a Radeon RX 6800. They both report the same PCI identity
> 1002:73bf and each has a different VBIOS.
> I hit the same VFCT bus-number mismatch on 7.2.10, but with a different
> outcome: on my machine the device-identity fallback actively breaks the second
> dGPU.
> I patched my kernel to remove the fallback, but I would like to have a
> better solution for my use case.
> Would it be possible to apply the patch only to APUs ? That would keep
> Oz's APU case working but a dGPU with a stale bus number would fall
> through to its own ROM, which is the source that is
> guaranteed to match the card in the slot.
> I can provide more details if needed, I am out of my depth here.

Should be fixed with this patch series:
https://patchwork.freedesktop.org/series/176969/

Alex

> Thanks
> Arnaud