[arch-general] [RFC] Potentially deprecating primus, bumblebee, virtualGL and primus_vk

[Emil Velikov]

On Wed, 13 Jan 2021 at 16:52, Archange <archange at archlinux.org> wrote:
>
> Le 12/01/2021 à 21:45, Emil Velikov a écrit :
> > On Tue, 12 Jan 2021 at 18:24, Archange <archange at archlinux.org> wrote:
> >
> >> OK, will try to check tomorrow with a friend that has an Optimus laptop.
> >>
> > Perfect, thanks in advance.
> >
> > To trigger the event one has to echo into a sysfs file... Don't recall
> > exactly, some of the following should be it.
> > a) If the nvidia module is driving an fbcon:
> >   - echo "0" > /sys/class/vtconsole/vtconX/bind
> > b) and/or a combination of the following
> >   - echo "remove" (or was it "unbind") > /sys/class/drm/cardX/device/uevent
> >   - echo "remove" (or was it "unbind") >
> > /sys/class/drm/cardX/device/driver/uevent
> >   - echo "1" > /sys/class/drm/cardX/device/driver/unbind
>

> 2) If the driver is loaded before X, it works for PRIME. However, the
> card refuse to unbind because it’s in use by X even if nothing is
> actually running on it.
>
It just works here so I suspect that a command or the order was off.

My setup:
- Intel/Nvidia system, monitor plugged/powered by Intel GPU
- Therefore fb0 is for Intel (alongside card0) and Nvidia does not
have fb device only card1.

What I've done:
- Toggle render offload ON via xrandr, try glxgears
- Toggle render offload OFF via xrandr
- Issue the removal - echo "remove" > /sys/class/drm/card1/uevent
- Confirm that it works - Xorg.0.log should list "removing GPU device
...blabla/card1"
- No Nvidia fb - skipping the vtcon magic
- Double-check nothing else is using the module - lsmod | grep
nvidia_drm -> returns 0
- Remove the nvidia module(s) - rmmod nvidia_drm (+ rest)

In practise the above approach should work with reverse PRIME but
honestly I haven't tried.

Can you give it a try, step-by-step and let me know if any issues you
encounter along the way.

Thanks
Emil