On Thu, 14 Jan 2021 at 18:15, Emil Velikov <emil.l.velikov@xxxxxxxxx> wrote: > > On Wed, 13 Jan 2021 at 16:52, Archange <archange@xxxxxxxxxxxxx> wrote: > > > > Le 12/01/2021 à 21:45, Emil Velikov a écrit : > > > On Tue, 12 Jan 2021 at 18:24, Archange <archange@xxxxxxxxxxxxx> 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. > Completely forgot: there is no need for an Optimus machine. The above is applicable for any multi GPU setup - dual AMD, dual Nvidia or any random 3+ combination. The only hardcoded assumption of a) dual and b) optimus machine seems** to be in BB. -Emil ** From a quick read through the code a while ago.
