Re: Laptop Working Group Github Issue Request - Multi-GPU Support

Found another example on Reddit
https://www.reddit.com/r/freebsd/comments/1ldqocy/frustrating_experience_installing_wayland_kde_on/

This time it's an AMD (Vega 10) + Nvidia (Geforce 1650 Mobile)
configuration. 

this would seem to indicate
https://www.reddit.com/r/freebsd/comments/1ii0da4/wayland_on_freebsd_142r_tldr/
that Intel + Nvidia encounters the same issue.

However both of these would indicate that in the case of Nvidia cards
that Wayland actually works, but X11 still needs configuration, unlike
the Framework 16's AMD + AMD situation where X11 needs configuration
and Wayland doesn't work.

Given the log complaint about:
VGA arbiter: cannot open kernel arbiter, no multi-card support.

My assumption is that this is what we're missing in order for it to
work: 
https://docs.kernel.org/gpu/vgaarbiter.html
https://www.x.org/wiki/VgaArbiter/

Thanks,
Luke

On Sat, 2025-06-07 at 14:29 -0700, Luke Wolf wrote:
> Hello,
> 
> I was looking through
> https://github.com/FreeBSDFoundation/proj-laptop/issues?page=1 and
> noticed that there doesn't seem to be an issue for Multi-GPU
> support. 
> 
> While it is true that the /dev/ nodes populate, and DRI_PRIME=1
> works.
> X11 and Wayland do not function as expected. On Linux no
> configuration
> is needed and X11 and Wayland work out of the box, on FreeBSD for X11
> you need to configure it in order to make it work and the handful of
> Wayland compositors I tried (KDE, Sway, Hikari) simply won't start
> and
> I'm not aware of a way to configure them to work. Presumably we're
> missing some sort of signaling around which is the "primary device". 
> 
> This effects the Framework 16 with Discrete GPU (AMD + AMD), but I
> would assume it effects most/all dual-gpu laptops.
> 
> Thanks,
> Luke