[Mesa-dev] [PATCH] anv: Fill holes in the VF VUE to zero

[Lionel Landwerlin]

I don't know how you find this stuff...

Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin at intel.com>

On 25/08/2018 23:17, Jason Ekstrand wrote:
> Cc: mesa-stable at lists.freedesktop.org
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=104809
> ---
>   src/intel/vulkan/genX_pipeline.c | 29 ++++++++++++++++++++++++++++-
>   1 file changed, 28 insertions(+), 1 deletion(-)
>
> diff --git a/src/intel/vulkan/genX_pipeline.c b/src/intel/vulkan/genX_pipeline.c
> index 022f324606e..b531205508c 100644
> --- a/src/intel/vulkan/genX_pipeline.c
> +++ b/src/intel/vulkan/genX_pipeline.c
> @@ -115,7 +115,34 @@ emit_vertex_input(struct anv_pipeline *pipeline,
>                          GENX(3DSTATE_VERTEX_ELEMENTS));
>      if (!p)
>         return;
> -   memset(p + 1, 0, (num_dwords - 1) * 4);
> +
> +   for (uint32_t i = 0; i < total_elems; i++) {
> +      /* The SKL docs for VERTEX_ELEMENT_STATE say:
> +       *
> +       *    "All elements must be valid from Element[0] to the last valid
> +       *    element. (I.e. if Element[2] is valid then Element[1] and
> +       *    Element[0] must also be valid)."
> +       *
> +       * The SKL docs for 3D_Vertex_Component_Control say:
> +       *
> +       *    "Don't store this component. (Not valid for Component 0, but can
> +       *    be used for Component 1-3)."
> +       *
> +       * So we can't just leave a vertex element blank and hope for the best.
> +       * We have to tell the VF hardware to put something in it; so we just
> +       * store a bunch of zero.
> +       *
> +       * TODO: Compact vertex elements so we never end up with holes.
> +       */
> +      struct GENX(VERTEX_ELEMENT_STATE) element = {
> +         .Valid = true,
> +         .Component0Control = VFCOMP_STORE_0,
> +         .Component1Control = VFCOMP_STORE_0,
> +         .Component2Control = VFCOMP_STORE_0,
> +         .Component3Control = VFCOMP_STORE_0,
> +      };
> +      GENX(VERTEX_ELEMENT_STATE_pack)(NULL, &p[1 + i * 2], &element);
> +   }
>   
>      for (uint32_t i = 0; i < info->vertexAttributeDescriptionCount; i++) {
>         const VkVertexInputAttributeDescription *desc =