[Mesa-dev] [PATCH v2 12/32] intel/isl: Disallow Yf and Ys for 1D depth surfaces

[Pohjolainen, Topi]

On Wed, Nov 07, 2018 at 11:17:38AM -0600, Jason Ekstrand wrote:
> On Wed, Nov 7, 2018 at 10:38 AM Pohjolainen, Topi <
> topi.pohjolainen at gmail.com> wrote:
> 
> > On Fri, Oct 12, 2018 at 01:46:42PM -0500, Jason Ekstrand wrote:
> > > ---
> > >  src/intel/isl/isl_gen7.c | 9 +++++++++
> > >  1 file changed, 9 insertions(+)
> > >
> > > diff --git a/src/intel/isl/isl_gen7.c b/src/intel/isl/isl_gen7.c
> > > index f6f7e1ba7dc..fe420e4fbd8 100644
> > > --- a/src/intel/isl/isl_gen7.c
> > > +++ b/src/intel/isl/isl_gen7.c
> > > @@ -217,6 +217,15 @@ isl_gen6_filter_tiling(const struct isl_device *dev,
> > >     if (isl_surf_usage_is_depth(info->usage)) {
> > >        /* Depth requires Y. */
> > >        *flags &= ISL_TILING_ANY_Y_MASK;
> > > +
> > > +      /* The Yf and Ys tilings for 1D can't be easily faked as a 2D
> > surface
> > > +       * because there's no calculable qpitch.
> >
> > Why is this problem for depth only?
> >
> 
> Because the depth hardware doesn't allow 1D.  For classic Y, we fake it as
> a 2D surface with a height of 1.  We can't do that with Yf and Ys so we
> have to disallow them.
> 
> Same applies to stencil but it's always W so it doesn't matter.

Ah, ok. It is actually the first thing documented in isl_emit_depth_stencil.c :)
I thought this was blit related. This patch is:

Reviewed-by: Topi Pohjolainen <topi.pohjolainen at intel.com>

> 
> --Jason
> 
> 
> > > +       *
> > > +       * TODO: In theory, on could fake it with surface offset tricks
> > but
> > > +       * that's currently being left as an exercise to the reader.
> > > +       */
> > > +      if (info->dim == ISL_SURF_DIM_1D)
> > > +         *flags &= ~ISL_TILING_STD_Y_MASK;
> > >     }
> > >
> > >     /* Separate stencil requires W tiling, and W tiling requires separate
> > > --
> > > 2.19.1
> > >
> > > _______________________________________________
> > > mesa-dev mailing list
> > > mesa-dev at lists.freedesktop.org
> > > https://lists.freedesktop.org/mailman/listinfo/mesa-dev
> >