Bug 92987

Summary: DRI2: fails to determine screen refresh rate when rendering is offloaded
Product: Mesa Reporter: Oliver Neukum <oliver>
Component: Mesa coreAssignee: mesa-dev
Status: RESOLVED WONTFIX QA Contact: mesa-dev
Severity: enhancement    
Priority: medium    
Version: unspecified   
Hardware: x86-64 (AMD64)   
OS: Linux (All)   
Whiteboard:
i915 platform: i915 features:

Description Oliver Neukum 2015-11-18 09:30:09 UTC
This is seen with glxgears and rendering offloaded to Radeon with Intel Haswell gfx. It is independent of the display used.

Glxgears renders with maximum rate if Radeon is used to render (DRI_PRIME=1) but limits itself to the refresh rate of 60Hz if Intel is used for rendering (DRI_PRIME=0)
Comment 1 Stefan Dirsch 2015-11-18 11:11:59 UTC
What's wrong with limiting fps to the refresh rate of 60Hz? vblank_mode in /etc/drirc (~/.drirc) controls this. It's enabled (=1) by default.
Comment 2 Oliver Neukum 2015-11-18 11:29:55 UTC
(In reply to Stefan Dirsch from comment #1)
> What's wrong with limiting fps to the refresh rate of 60Hz? vblank_mode in
> /etc/drirc (~/.drirc) controls this. It's enabled (=1) by default.

Nothing is wrong with that. It is wrong not to do it. The error case is rendering with Radeon. I suppose Mesa fails to understand that the rendering device needs to take the refresh rate of an alien crtc.
Comment 3 Stefan Dirsch 2018-07-17 10:37:45 UTC
(In reply to Oliver Neukum from comment #2)
> (In reply to Stefan Dirsch from comment #1)
> > What's wrong with limiting fps to the refresh rate of 60Hz? vblank_mode in
> > /etc/drirc (~/.drirc) controls this. It's enabled (=1) by default.
> 
> Nothing is wrong with that. It is wrong not to do it. The error case is
> rendering with Radeon. I suppose Mesa fails to understand that the rendering
> device needs to take the refresh rate of an alien crtc.

I see. I'm afraid this is a feature request somehow. Right now you need to set it manually. :-(
Comment 4 Michel Dänzer 2018-07-17 10:42:25 UTC
This works as expected with DRI3, will probably never be fixed with DRI2.
Comment 5 Stefan Dirsch 2018-07-17 13:44:56 UTC
(In reply to Michel Dänzer from comment #4)
> This works as expected with DRI3, will probably never be fixed with DRI2.

Ah. Cool. So let's close it as WONTFIX. ;-)

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