Hi DRM subsystem developers,
I ran into this patch where overlay plane was switched to cursor plane because there was no proper cursor plane available on the display hardware: https://lkml.org/lkml/2018/3/17/120. Can we discuss whether to have a policy of using a normal plane for cursor plane in case a dedicated HW cursor plane is missing?
Daniel Vetter suggests that it might be fine to use normal plane for cursor plane because how to use the plane would be only "a hint to userspace" (see the email linked).
My motivation for having this discussion is that the newer Allwinner SoCs don't have dedicated HW cursor plane and the sun4i DRM driver currently uses the extra planes as overlay planes which makes moving the cursor on Xfce4 DE a terrible experience. To have better cursor moving experience one overlay plane would need to be sacrificed.
Also, I probably missed some recipients for this email so please forward it to the recipients you think might be interested about this.
Best regards, Joonas