Comment by gryn
only on the primary display. once you had more than one display there were only workarounds.
only on the primary display. once you had more than one display there were only workarounds.
(I'm posting in a reply in part because the edit window is long since past.)
Yeah. I'm actually quite interested in hearing what "workarounds" and/or misbehavior you're talking about. 'amdgpu(4)' says this about the TearFree property:
Option "TearFree" "boolean"
Set the default value of the per-output ’TearFree’ property,
which controls tearing prevention using the hardware page flip‐
ping mechanism. TearFree is on for any CRTC associated with one
or more outputs with TearFree on. Two separate scanout buffers
need to be allocated for each CRTC with TearFree on. If this op‐
tion is set, the default value of the property is ’on’ or ’off’
accordingly. If this option isn’t set, the default value of the
property is auto, which means that TearFree is on for rotated
outputs, outputs with RandR transforms applied, for RandR 1.4
secondary outputs, and if ’VariableRefresh’ is enabled, otherwise
it’s off.
I don't know what "workarounds" you're talking about, or what unwanted behavior that I presume you're talking about. Would you be more specific?
I ask because just a few minutes ago, I ran VRRTest [0] on my dual-monitor machine and saw no screen tearing on either monitor. Because VRR is disabled in multi-monitor setups, I saw juddering on both monitors when I commanded VRRTest render rates that weren't a multiple of the monitor's refresh rate, but no tearing at all.
My setup:
* Both monitors hooked up via DisplayPort
* Radeon 9070 (non-XT)
* Gentoo Linux, running almost all ~amd64 packages.
* x11-base/xorg-server-21.1.20
* x11-drivers/xf86-video-amdgpu-25.0.0-r1
* x11-drivers/xf86-video-ati-22.0.0
* sys-kernel/gentoo-sources-6.18.5
* KDE and Plasma packages are either version 6.22.0 or 6.5.5. I CBA to get a complete list, as there are so many relevant packages.
[0] <https://github.com/Nixola/VRRTest>