[Intel-gfx] [PATCH 2/6] drm/i915: Always enable the cursor right after the primary plane

[Egbert Eich]

On Tue, May 21, 2013 at 05:17:27PM +0200, Egbert Eich wrote:
> On Wed, May 08, 2013 at 12:50:24PM +0300, ville.syrjala at linux.intel.com wrote:
> > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > 
> > Follow the same sequence when enabling the cursor plane during
> > modeset. No point in doing this stuff in different order on different
> > generations.
> > 
> > This should also avoid a needless wait for vblank for the g4x cursor
> > workaround when the cursor gets enabled anyway.
> > 
> > Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > ---
> >  drivers/gpu/drm/i915/intel_display.c | 10 ++++------
> >  1 file changed, 4 insertions(+), 6 deletions(-)
> > 
> > @@ -3727,6 +3725,7 @@ static void i9xx_crtc_enable(struct drm_crtc *crtc)
> >  
> >  	intel_enable_pipe(dev_priv, pipe, false);
> >  	intel_enable_plane(dev_priv, plane, pipe);
> > +	intel_crtc_update_cursor(crtc, true);
> >  	if (IS_G4X(dev))
> >  		g4x_fixup_plane(dev_priv, pipe);
> >  
> 
> As discussed on IRC this may interfere with 
> 
> commit 61bc95c1fbbb6a08b55bbe161fdf1ea5493fc595
> Author: Egbert Eich <eich at suse.com>
> Date:   Mon Mar 4 09:24:38 2013 -0500
> 
>     DRM/i915: On G45 enable cursor plane briefly after enabling the display plane.
> 
> described in https://bugs.freedesktop.org/show_bug.cgi?id=61457
> 

Today I had the chance to test this. First I tried
if I can still reproduce the blank with this patch
added when I disable my voodoo g4x_fixup_plane():
It turned out it still happens however very rarely
(like 1 out of 20 tries). When I reenabled my voodoo
the issue still occurred.
I had to switch two lines around, ie:

 	intel_enable_plane(dev_priv, plane, pipe);
 	if (IS_G4X(dev))
 		g4x_fixup_plane(dev_priv, pipe);
+	intel_crtc_update_cursor(crtc, true);

to avoid the blank screen issue - which is it didn't
happen in ~75 tries.

With this change:

Acked-by: Egbert Eich <eich at suse.com>


Cheers,
	Egbert.