Re: [RFCv3 11/14] drm/i915: Intel-specific primary plane handling

[Daniel Vetter <daniel@ffwll.ch>]

On Wed, Mar 19, 2014 at 01:11:26PM +0100, Daniel Vetter wrote:
> On Tue, Mar 18, 2014 at 05:22:56PM -0700, Matt Roper wrote:
> > Intel hardware allows the primary plane to be disabled independently of
> > the CRTC.  Provide custom primary plane handling to allow this.
> > 
> > Cc: Intel Graphics Development <intel-gfx@lists.freedesktop.org>
> > Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
> 
> Overall this is imo a new feature since it exposes primary plane disabling
> to userspace. Which means I want a crc based igt for this. Two interesting
> cases imo:
> 
> 1) Partially visible primary plane behind an overlay plane. Disabling it
> should change those areas from the primary plane to grey or something, so
> easy to check with CRCs.
> 
> 2) Primary plane + cursor, disable primary plane. Then check that the
> cursor is still working. Same for overlay sprites.
> 
> At least on all currently supported platforms we don't have unified planes
> in the hardware, so imo it's worth to check that this works properly.

One big reason I've forgotten why I really want testcase for this is that
historically our code has fallen over in _really_ bad ways without a
primary fb. fastboot has brought a lot of these issues to light (since we
occasionally fail to wrap up the firmware's fb properly). So having a bit
of a baseline testcase so that we can easily add regression tests for
specific bugs once we inevitably run into them is good prep work, too.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch