[Mesa-dev] [PATCH 2/2] anv: do not subtract the base layer to copute depth in 3DSTATE_DEPTH_BUFFER

[Iago Toral]

On Fri, 2017-02-24 at 07:25 -0800, Jason Ekstrand wrote:
> On Feb 23, 2017 11:40 PM, "Iago Toral Quiroga" <itoral at igalia.com>
> wrote:
> According to the PRM description of the Depth field:
> 
>   "This field specifies the total number of levels for a volume
> texture
>    or the number of array elements allowed to be accessed starting at
> the
>    Minimum Array Element for arrayed surfaces"
> 
> However, ISL defines array_len as the length of the range
> [base_array_layer, base_array_layer + array_len], so it already
> represents
> a value relative to the base array layer like the hardware expects.
> 
> This fixes a number of new CTS tests that would crash otherwise:
> dEQP-VK.pipeline.render_to_image.*
> ---
>  src/intel/vulkan/genX_cmd_buffer.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/src/intel/vulkan/genX_cmd_buffer.c
> b/src/intel/vulkan/genX_cmd_buffer.c
> index 40a72f4..3c7b544 100644
> --- a/src/intel/vulkan/genX_cmd_buffer.c
> +++ b/src/intel/vulkan/genX_cmd_buffer.c
> @@ -2269,8 +2269,7 @@ cmd_buffer_emit_depth_stencil(struct
> anv_cmd_buffer *cmd_buffer)
> 
>           assert(image->depth_surface.isl.dim != ISL_SURF_DIM_3D);
>           db.Depth =
> -         db.RenderTargetViewExtent =
> -            iview->isl.array_len - iview->isl.base_array_layer - 1;
> +         db.RenderTargetViewExtent = iview->isl.array_len;
> 
> Don't we still want the -1?

The PRM says this about the Depth field:

"This field specifies (...) the number of array elements allowed to be
accessed starting at the Minimum Array Element for arrayed surfaces"

And in anv_get_layerCount, we compute this value as:

range->layerCount == VK_REMAINING_ARRAY_LAYERS ?
   image->array_size - range->baseArrayLayer : range->layerCount;

Since we want the number of elements including Minimum Array Element, I
think we don't want the subtraction.

Iago

>  #if GEN_GEN >= 8
>           db.SurfaceQPitch =
> --
> 2.7.4
> 
>