[Intel-gfx] [PATCH] drm/i915: The hw does not support source offsets into a YUV linear fb

[Chris Wilson]

On Wed, 19 Dec 2012 13:56:12 +0200, Ville Syrjälä <ville.syrjala at linux.intel.com> wrote:
> On Tue, Dec 18, 2012 at 11:57:05PM +0100, Daniel Vetter wrote:
> > On Tue, Dec 18, 2012 at 11:51 PM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> > > As we can only pass in the base address of the first plane, we can not
> > > control the offset into the subsampled chroma planes. This means that we
> > > cannot support a source offset into a YUV* linear framebuffer. However,
> > > for tiled framebuffers we can tell the hardware which pixels to read
> > > from. So if we see a source offset into a linear YUV framebuffer, report
> > > the invalid value back to userspace.
> > >
> > > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> 
> I can't see the original mail with the patch, where did it go?
> 
> > Aren't all the yuv formats we support packet planar?
> 
> No idea what packet planar means. All we currently support are packed
> formats. The problem is that our code doesn't handle fb->offsets[].
> 
> If you're talking about src_x,src_y then those do work, at least on my
> atomic branch. I don't remember changing the src_x/src_y related code
> that much (apart from adding proper clipping), so I'm fairly sure they
> should work in the upstream code as well.

They only work with a tiled source, as far as my investigation into the
current code revealed.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre