[Intel-gfx] [PATCH] drm/i915: Adding dbuf support for skl nv12 format.

[Daniel Vetter]

On Mon, Apr 27, 2015 at 03:47:37PM -0700, Chandra Konduru wrote:
> Skylake nv12 format requires dbuf (aka. ddb) calculations
> and programming for each of y and uv sub-planes. Made minor
> changes to reuse current dbuf calculations and programming
> for uv plane. i.e., with this change, existing computation
> is used for either packed format or uv portion of nv12
> depending on incoming format. Added new code for dbuf
> computation and programming for y plane.
> 
> This patch is a pre-requisite for adding NV12 format support.
> Actual nv12 support is coming in later patches.
> 
> Signed-off-by: Chandra Konduru <chandra.konduru at intel.com>

Just aside (and not a blocker for this patch really). Do we have nv12
subtest in all the relevant plane tests (rotation, scaling, ...) to
exercise this code? Not sure whether we can redo the yuv->rgb conversion
correctly in software to match hw, might need to pick special colors that
convert accurately.

Anyway given how often we've broken the sprite code I really think we need
full functional tests (i.e. including crc checks).
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch