On Thu, Dec 19, 2024 at 06:03:58PM +0100, Lukas Wunner wrote: > On Tue, Dec 17, 2024 at 10:22:22AM +0200, Mika Westerberg wrote: > > In typical cases there is always graphics driver loaded, and also all > > the cables are connected but for instance in Intel graphics CI they only > > load the graphics driver after the system is fully booted up. This > > makes the driver to tear down the DisplayPort tunnel. To help this case > > we allow passing bigger or indefinite timeout through a new module > > parameter (dprx_timeout). To keep the driver bit more responsive during > > that time we change the way DisplayPort tunnels get activated. We first > > do the normal tunnel setup and then run the polling of DPRX capabilities > > read completion in a separate worker. This also makes the driver to > > accept bandwidth requests to already established DisplayPort tunnels > > more responsive. > > Does this mean one has to add that command line option unless i915 > is already loaded on boot (or built-in)? I can easily see i915 > not being in the initrd for some reason but being loaded only > after the root filesystem is mounted. And that in turn may > take a while if the user has to enter a password for disk encryption. > If the user has to add a command line option in such cases I think > that would be very inconvenient. Typically no. We wait for the 12s now before tearing down the tunnel and that should be enough for i915 to kick in and read the capabilities. At least we did not see any problems during testing. But the command line option is there as "escape hatch" if defaults don't work.
