More than a year ago I elaborated whether KWin should or should not add support for NVIDIA’s proprietary Wayland solution. I think it is time to look at the situation of Plasma/Wayland and NVIDIA again. In case you haven’t read my previous blog post on that topic I recommend to read it as I use it as the base for this blog post.

Compared to a year ago not much has changed: NVIDIA still does not support the standard Linux solution gbm, which is supported by all vendors and nowadays even going to enter the mobile space. E.g. the purism phone is going to have a standard graphics stack with gbm. So no additional code required. But NVIDIA doesn’t support gbm. Instead it has a proprietary implementation called EGLStreams, which no other vendor implements. Due to that Plasma/Wayland cannot support OpenGL for NVIDIA users.

But current KWin master branch (what will become 5.12) supports automatical fallback to Qpainter compositing in case OpenGL fails. With that it should be possible to run Plasma/Wayland on NVIDIA hardware. Granted it won’t be accelerated, but as explained above that is only NVIDIA’S fault. Also I have not tested this yet. It might be that NVIDIA doesn’t support dumb buffers on DRM.

In my blog post from last year I elaborated whether KWin should add support for NVIDIA’S proprietary solution. I put out a requirement that the patches for Weston need to be merged first:

For KWin such patches do not exist and we have no plans to develop such an adaption as long as the patches are not merged into Weston. Even if there would be patches, we would not merge them as long as they are not merged into Weston.

A year passed and nothing happened. I don’t expect anything further will happen: the patches won’t be merged into Weston. Given that it doesn’t make any sense to make this a requirement for KWin. If we hold up the requirement it would be like saying we would never accept it.

Last year I hoped that XDC would find a solution for the problem:

We do hope that at XDC the discussions will have a positive end and that there will be only one implementation.

And it looked positive: a new universal buffer allocation library got announced. I hoped that this would solve the situation pretty quickly. The new library would get implemented, Mesa and NVIDIA add support for it, we slightly adjust our code and drop gbm. Everybody happy.

But now another XDC passed and from what I understand not much process was made. The library is not ready and no driver uses it. We waited one year for it, I doubt waiting another year will change the situation. Realistically I think it will take another two to three years for the library to get implemented if at all. Then it will take about a year for Mesa gaining support and shipping a release. Yet another year for distributions shipping with that version so that we can depend on it without people killing us. So maybe in five years there will be a replacement. I don’t think we can wait that long.

So does this mean KWin will gain support for EGLStreams? Certainly not! I do not think that the KDE community should spend any time to support NVIDIA’s proprietary solution! We are a free software community and we should not implement code which only benefits proprietary non-free solutions. There are way more free things to do to improve Wayland without having to write code for proprietary solutions.

Also there is another aspect which I did not consider in my blog post last year: XWayland. XWayland also uses gbm and does not have support for NVIDIA’s proprietary solution. Due to that one does not have OpenGL for any legacy X application. This probably includes most games, but currently also browsers such as Firefox and Chromium. I don’t think that this would give a satisfying experience to NVIDIA users. And it is also hardly better than rendering everything through the QPainter compositor. This is another reason for the KDE Community to not spend any time on implementing support for EGLStreams.

But I think there is lots NVIDIA could do. Today I would accept a patch for EGLStreams in KWin if NVIDIA provides it. I would not be happy about it, but I would not veto it. If it is well implemented and doesn’t introduce problems for the gbm implementation I would not really have an argument against it. But I expect NVIDIA to do it. I don’t want a contribution from a non-NVIDIA developer. This mess was created by NVIDIA, NVIDIA needs to fix it.

Similar I think that NVIDIA should adjust XWayland. I understand that NVIDIA is not happy with the design of XWayland, but nevertheless they should make it work. Their users pay quite some money for the hardware. I think they have a right to demand from NVIDIA to fix this situation. Ideal would of course be NVIDIA adopting gbm. But as that seems unlikely, I think it is the duty of NVIDIA to provide patches for their users.