[Bug 109392] New: modesetting driver + amdgpu.dc=1 always enforces vsync

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=109392

            Bug ID: 109392
           Summary: modesetting driver + amdgpu.dc=1 always enforces vsync
           Product: xorg
           Version: git
          Hardware: x86-64 (AMD64)
                OS: Linux (All)
            Status: NEW
          Severity: normal
          Priority: medium
         Component: Driver/AMDgpu
          Assignee: xorg-driver-ati at lists.x.org
          Reporter: tempel.julian at gmail.com
        QA Contact: xorg-team at lists.x.org

Created attachment 143158
  --> https://bugs.freedesktop.org/attachment.cgi?id=143158&action=edit
dmesg log

When amdgpu.dc=1 and modesetting driver are used at the same time, fps in 3D
applications can't exceed monitor refreshrate and there is always no tearing,
despite of vsync enabled or not in the applications.
Happens with both radeonsi and radv. For OGL apps, forcing vsync off via
vblank_mode=0 also doesn't show any effect in this case.

The issue doesn't occur with amdgpu.dc=0 + modesetting or with
xf86-video-amdgpu.

Though I think having an option for globally enforcing vsync would be tempting
if an application doesn't offer vsync for whatever reasons. radv and amdvlk
also don't offer options to enforce vsync, just radeonsi does.
Perhaps it could be a sub-option for TearFree?

linux drm-next-5.1-wip 5acc93145bf97a0d59ee65255cae8e1bd0623b07
xorg-server 1.20.3

-- 
You are receiving this mail because:
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.x.org/archives/xorg-driver-ati/attachments/20190119/d601f863/attachment.html>