Wayland shows black screen under 4K resolution on some GPUs with 2GB RAM
I'm not sure if it's a Wayland issue but I seems like it is.
I have two different 2GB GPUs, Radeon HD 7870 and GeForce GT 730 (it identifies as
NVIDIA Corporation GK208B [GeForce GT 730] [10de:1287] (rev a1)).
X11 works well in 4K resolution on both these GPUs.
Though I'm getting black screen when I start GDM under Wayland. When I launch weston (directly or through
weston-launch), I'm getting black screen with blinking (sic!) but movable mouse cursor. No errors, no crashes, no debug messages, just blank screen.
I've tried both proprietary NVIDIA driver (440.82-r3 with KMS enabled) and Nouveau. I've tried different kernels (5.7.4, 5.7.3, 5.4.38), different mesa versions (19.3.5, 20.0.8, 20.1.1).
Under all the configurations Wayland worked fine when I forced 1920x1080 resolution through
/var/lib/gdm/.config/monitors.xml or by connecting a non-4K display. It worked fine even with proprietary nvidia drivers (I've been always checking that I'm actually running wayland through
XDG_SESSION_TYPE and by running Wayland version of Firefox)
It's worth to stay that
.config/weston.ini does not help - in case I have a 4K display connected I'm always getting black screen even if I have this in my
[output] name=HDMI-A-1 mode=1920x1080
Wayland launches fine in 4K in case I use my Radeon VII card instead of both these "old" GPUs. Though I believe that these "old" GPUs should work fine with 4K - I'm able to run Starcraft II (on Windows) on them and it's even kinda playable in 4K.
It's also interesting that Wayland works fine with another 2GB GPU I have, Radeon R5 230.