Re: [PATCH] drm: DON'T require each CRTC to have a unique primary plane
From: Simon Ser
Date: Mon Mar 29 2021 - 11:37:23 EST
On Monday, March 29th, 2021 at 5:32 PM, Paul Cercueil <paul@xxxxxxxxxxxxxxx> wrote:
> Making the second plane an overlay would break the ABI, which is never
> something I'm happy to do; but I'd prefer to do it now than later.
Yeah, I wonder if some user-space depends on this behavior somehow?
> I still have concerns about the user-space being "clever" enough to
> know it can disable the primary plane. Can e.g. wlroots handle that?
wlroots will always pick the first primary plane, and will never use
overlays. The plan is to use libliftoff [1] to make use of overlay
planes. libliftoff should already support the scenario you describe.
I think Weston supports that too.
[1]: https://github.com/emersion/libliftoff