[Mesa-dev] [PATCH] anv: enable sampling from fast-cleared images on SKL

[Nanley Chery]

On Thu, Mar 23, 2017 at 12:25:28PM +0100, Samuel Iglesias Gonsálvez wrote:
> A resolve is not needed on Skylake in this case. We were forcing
> a resolve because we set the input_aux_usage to ISL_AUX_USAGE_NONE.
> 
> Signed-off-by: Samuel Iglesias Gonsálvez <siglesias at igalia.com>
> ---
> 
> This doesn't fix the problem with BDW but I found it while reviewing
> the code.
> 
>  src/intel/vulkan/genX_cmd_buffer.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/src/intel/vulkan/genX_cmd_buffer.c b/src/intel/vulkan/genX_cmd_buffer.c
> index e2364dbfd52..39856b9af7c 100644
> --- a/src/intel/vulkan/genX_cmd_buffer.c
> +++ b/src/intel/vulkan/genX_cmd_buffer.c
> @@ -305,8 +305,8 @@ color_attachment_compute_aux_usage(struct anv_device *device,
>            * doesn't also support color compression.
>            */
>           att_state->input_aux_usage = ISL_AUX_USAGE_NONE;
> -      } else if (GEN_GEN == 8) {
> -         /* Broadwell can sample from fast-cleared images */
> +      } else if (GEN_GEN >= 8) {
> +         /* Broadwell/Skylake can sample from fast-cleared images */
>           att_state->input_aux_usage = ISL_AUX_USAGE_CCS_D;

This doesn't work in all cases. SKL can only sample from CCS_D if the
format is supported for CCS_E.

By the way, I actually have a work-in-progress branch that has a patch to do this:
https://cgit.freedesktop.org/~nchery/mesa/commit/?h=ccs-layouts/1-ccsd-layout&id=e428f44e1835cb00f52848d09350957ef6f73495