[Intel-gfx] [PATCH] drm/i915/skl: Support Y tiling in MMIO flips

[Daniel Vetter]

On Mon, Apr 20, 2015 at 04:22:48PM +0100, Tvrtko Ursulin wrote:
> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> 
> Add Y tiling support to skl_do_mmio_flip.
> 
> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> Cc: Damien Lespiau <damien.lespiau at intel.com>
> Cc: Sonika Jindal <sonika.jindal at intel.com>
> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> ---
> Looks like we completely missed this completely parallel instance of plane
> programming code when working on Y tiling support!
> 
> Will rotation need supporting here as well?

Oh dear this is a bit ugly. We definitely need either this for 4.1 or take
out the Y-tiling support for 4.1. Rotation only made 4.2, so I think
we're good, but we do indeed need to take rotation into account here too.

And it seems like we also need a pile of igt testcases to make sure
Y-tiling, rotation (even 180 probably) works correctly with pageflips. Yay
for kms_flip growing even more.

> And what about the comment at intel_do_mmio_flip saying this was only
> temporary code?

Well once we have atomic this code will disappear, but it sounds like
that's still a bit off unfortunately.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch