[Intel-gfx] [PATCH 5/6] drm/i915: Add 180 degree primary plane rotation support

[Daniel Vetter]

On Tue, Jul 15, 2014 at 11:11:37AM +0200, Daniel Vetter wrote:
> On Tue, Jul 15, 2014 at 02:10:28PM +0530, sonika.jindal at intel.com wrote:
> > +		/* FBC does not work on some platforms for rotated planes */
> > +			if (INTEL_INFO(dev)->gen <= 4 && !IS_G4X(dev)) {
> > +				if (dev_priv->fbc.plane == intel_crtc->plane &&
> > +				intel_plane->rotation != BIT(DRM_ROTATE_0))
> > +					intel_disable_fbc(dev);
> > +			/* If rotation was set earlier and new rotation is 0,
> > +			we might have disabled fbc earlier. So update it now */
> > +				else if (intel_plane->rotation == BIT(DRM_ROTATE_0)
> > +					&& old_val != BIT(DRM_ROTATE_0)) {
> > +					mutex_lock(&dev->struct_mutex);
> > +					intel_update_fbc(dev);
> > +					mutex_unlock(&dev->struct_mutex);
> > +				}
> > +			}
> 
> Indentation is screwed up here. Also if we convert some of the checks into
> early bails we could de-indent this by one level.
> 
> Also Chris mentioned that on some platforms this won't work and it's more
> future-proof to just do a full modeset until we have the proper
> infrastructure.

Apparently this review here was never addressed, as Chris just pointed out
on irc. I've dropped the patch again.

I think we need:
- The same sequence as with the sprite set_property function, i.e. we need
  to call the update_plane function (not the raw low-level one, the
  high-level with all the checks).
- The fbc check is wrong and will miss updates when the crtc is off. We
  need to move this into the general list of checks in intel_update_fbc.
- Since this seems to be buggy I want added testcases to combine fbc
  correctness with screen rotation. Probably best to reuse the existing
  fbc testcase and add a bunch or rotated tests.

Thanks, Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch