[Mesa-dev] [PATCH] i965: Call prepare_external after implicit window-system MSAA resolves

[Tapani Pälli]

This fixes the issue;
Tested-by: Tapani Pälli <tapani.palli at intel.com>

On 02/01/2018 03:41 AM, Jason Ekstrand wrote:
> This fixes some rendering corruption in a couple of Android apps that
> use window-system MSAA.
> 
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=104741
> Cc: mesa-stable at lists.freedesktop.org
> Cc: Chad Versace <chadversary at chromium.org>
> ---
>   src/mesa/drivers/dri/i965/brw_context.c | 15 +++++++++++++++
>   1 file changed, 15 insertions(+)
> 
> diff --git a/src/mesa/drivers/dri/i965/brw_context.c b/src/mesa/drivers/dri/i965/brw_context.c
> index addacf2..e5d3b5c 100644
> --- a/src/mesa/drivers/dri/i965/brw_context.c
> +++ b/src/mesa/drivers/dri/i965/brw_context.c
> @@ -1283,6 +1283,21 @@ intel_resolve_for_dri2_flush(struct brw_context *brw,
>            intel_miptree_prepare_external(brw, rb->mt);
>         } else {
>            intel_renderbuffer_downsample(brw, rb);
> +
> +         /* Call prepare_external on the single-sample miptree to do any
> +          * needed resolves prior to handing it off to the window system.
> +          * This is needed in the case that rb->singlesample_mt is Y-tiled
> +          * with CCS_E enabled but without I915_FORMAT_MOD_Y_TILED_CCS_E.  In
> +          * this case, the MSAA resolve above will write compressed data into
> +          * rb->singlesample_mt.
> +          *
> +          * TODO: Some day, if we decide to care about the tiny performance
> +          * hit we're taking by doing the MSAA resolve and then a CCS resolve,
> +          * we could detect this case and just allocate the single-sampled
> +          * miptree without aux.  However, that would be a lot of plumbing and
> +          * this is a rather exotic case so it's not really worth it.
> +          */
> +         intel_miptree_prepare_external(brw, rb->singlesample_mt);
>         }
>      }
>   }
>