[Intel-gfx] TearFree true and Screen Rotation on Skylake

[Chris Wilson]

Quoting Mattias Nyman (2017-07-04 10:50:00)
> Hey!
> I am unable to rotate my screen to left or right using Skylake Integrated
> Graphics with the 
> Option TearFree true
> in the /usr/share/X11/xorg.conf.d/20-intel.conf
> 
> The screen turns black for a second, before returning to its previous
> orientation.
> 
> Terminal output:
> $ xrandr --output HDMI1 --rotate left
> xrandr: Configure crtc 0 failed
> 
> Simply turning the TearFree option to false enables the screen to be rotated
> again.
> 
> I have installed the recommended 2017Q1 Intel Graphics Stack.
> 
> I have described the issue on the linuxgraphics forum where I also included the
> full 20-intel.conf, lspci -v output and the Xorg.0.log
> https://01.org/linuxgraphics/forum/update-tool-support-forum/
> tearfree-and-screen-rotation
> 
> Do let me know if I have missed something simple to get this working, or if I
> can provide any more logs our other output to help with the issue.

commit c62177ec321e009a1abcdc969dd808fb37136013
Author: Chris Wilson <chris at chris-wilson.co.uk>
Date:   Wed Apr 20 21:31:46 2016 +0100

    sna: Force the shadow buffer even after we fail to set the crtc for TearFree
    
    As the first choice of orientation and tiling may be invalid, e.g.
    left/right rotation on Skylake, we need to force the second pass here to
    try and an alternate non-native rotation.