[PATCH 4/5] drm/i915: Add rotation support for the cursor plane

[Sagar Arun Kamble]

On Fri, 2014-02-14 at 13:39 +0200, Ville Syrjälä wrote:
> On Fri, Feb 14, 2014 at 04:31:17PM +0530, Sagar Arun Kamble wrote:
> > On Wed, 2014-02-12 at 23:15 +0200, ville.syrjala at linux.intel.com wrote:
> > > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > > 
> > > The cursor plane also supports 180 degree rotation. Add a new
> > > "cursor-rotation" property on the crtc which controls this.
> > > 
> > > Unlike sprites, the cursor has a fixed size, so if you have a small
> > > cursor image with the rest of the bo filled by transparent pixels,
> > > simply flipping the rotation property will cause the visible part
> > > of the cursor to shift. This is something to keep in mind when
> > > using cursor rotation.
> > By flipping you meant setting 180 degree rotation?
> 
> Yes.
> 
> > Don't we have to adjust the cursor base as well to the lower right
> > corner apart from setting the control bit?
> 
> No, the hardware does that automagically. Hmm. Except on gen4
> apparently. Looks like I need to test on gen4, and fix it if it's
> really the case.
I tried on BYT system and 180 rotation on cursor plane is showing
garbage data in cursor plane. We might need to adjust the cursor base.
Another thing, pipe rotation somehow did not work for me when I do this:
echo 0x4 > /sys/kernel/debug/dri/0/i915_pipe_rotation
Only cursor plane had impact. Need to debug this as well.
>