Latest drm-devel-kmod port not working? (was: Re: Kernel changes causing AMDGPU / DRM to fail? i2c related?)

Am 29.01.22 um 23:25 schrieb Tomoaki AOKI:
> On Sat, 29 Jan 2022 22:25:17 +0100
> Stefan Esser <se@FreeBSD.org> wrote:
> 
>> After rebooting with freshly built world, kernel and the amdgpu driver
>> my console stopped working. It goes blank and the display goes into a
>> power save mode, as soon as the amdgpu driver is loaded.
>>
>> The GPU (a Radeon R7 250E) is correctly detected as before, but there
>> is an error message "drmn0: [drm] Cannot find any crtc or sizes".
[...]
> Are you sure your ports tree is up-to-date and graphics/drm-*-kmod
> you installed (IIRC, should be needed for -intel and -amdgpu drivers)
> is also updated? drm-*-kmod could be affected by LinuxKPI updates in
> base.

Yes, I rebuild the system from sources at least once a day, but do
only reboot every few days, especially if there has been any change
that might cause incompatibilities between kernel and user land.

And I always rebuild all KLDs together with the kernel, including
all the driver module ports relevant for X11.

>  *There can be some (sometime very wide) timeframe between LinuxKPI
>   update and corresponding linux-*-kmod catches up with it.

X11 was working just fine on a system built and rebooted a few days
ago.

> Looking into cgit.freebsd.org, at least drm-current-kmod is updated 36
> hours ago. Not sure it's related or not, though.

I had missed that update - and YES you are right. I'm using the devel
version and after reverting the update to drm_v5.5.19_7 the driver
does attach again.

Thanks for the hint!

>  *I always prefer nvidia dGPU because of these dangerous span.
>   So I've forced to choose ThinkPad P series (without "s") which
>   usually can disable CPU-integrated Intel GPU and run nvidia GPU
>   alone though BIOS setting.

I had issues with Nvidia cards (and the closed source driver modules
and libraries) before and for that reason bought a passively cooled
Radeon card for this development workstation.

Best regards, STefan