[Mesa-dev] [PATCH 29/29] anv: Use blorp_ccs_ambiguate instead of fast-clears

[Jason Ekstrand]

Even though the blorp pass looks a bit on the sketchy side, the end
result in the Vulkan driver is very nice.  Instead of having this weird
case where you do a fast clear and then maybe have to resolve, we just
do the ambiguate and are done with it.  The ambiguate does exactly what
we want of setting all the CCS values to 0 which puts it inot the
pass-through state.
---
 src/intel/vulkan/anv_blorp.c       |  5 +++++
 src/intel/vulkan/genX_cmd_buffer.c | 40 ++------------------------------------
 2 files changed, 7 insertions(+), 38 deletions(-)

diff --git a/src/intel/vulkan/anv_blorp.c b/src/intel/vulkan/anv_blorp.c
index 45d7b12..84ac720 100644
--- a/src/intel/vulkan/anv_blorp.c
+++ b/src/intel/vulkan/anv_blorp.c
@@ -1705,6 +1705,11 @@ anv_image_ccs_op(struct anv_cmd_buffer *cmd_buffer,
                         surf.surf->format, isl_to_blorp_fast_clear_op(ccs_op));
       break;
    case ISL_AUX_OP_AMBIGUATE:
+      for (uint32_t a = 0; a < layer_count; a++) {
+         const uint32_t layer = base_layer + a;
+         blorp_ccs_ambiguate(&batch, &surf, level, layer);
+      }
+      break;
    default:
       unreachable("Unsupported CCS operation");
    }
diff --git a/src/intel/vulkan/genX_cmd_buffer.c b/src/intel/vulkan/genX_cmd_buffer.c
index dcd5a8f..e8a4d90 100644
--- a/src/intel/vulkan/genX_cmd_buffer.c
+++ b/src/intel/vulkan/genX_cmd_buffer.c
@@ -614,17 +614,7 @@ init_fast_clear_state_entry(struct anv_cmd_buffer *cmd_buffer,
    uint32_t plane = anv_image_aspect_to_plane(image->aspects, aspect);
    enum isl_aux_usage aux_usage = image->planes[plane].aux_usage;
 
-   /* The resolve flag should updated to signify that fast-clear/compression
-    * data needs to be removed when leaving the undefined layout. Such data
-    * may need to be removed if it would cause accesses to the color buffer
-    * to return incorrect data. The fast clear data in CCS_D buffers should
-    * be removed because CCS_D isn't enabled all the time.
-    */
-   if (aux_usage == ISL_AUX_USAGE_NONE) {
-      set_image_needs_resolve_bits(cmd_buffer, image, aspect, level, ~0);
-   } else {
-      clear_image_needs_resolve_bits(cmd_buffer, image, aspect, level, ~0);
-   }
+   clear_image_needs_resolve_bits(cmd_buffer, image, aspect, level, ~0);
 
    /* The fast clear value dword(s) will be copied into a surface state object.
     * Ensure that the restrictions of the fields in the dword(s) are followed.
@@ -830,7 +820,7 @@ transition_color_buffer(struct anv_cmd_buffer *cmd_buffer,
                MIN2(layer_count, anv_image_aux_layers(image, aspect, level));
             anv_image_ccs_op(cmd_buffer, image, aspect, level,
                              base_layer, level_layer_count,
-                             ISL_AUX_OP_FAST_CLEAR, false);
+                             ISL_AUX_OP_AMBIGUATE, false);
          }
       } else if (image->samples > 1) {
          if (image->samples == 4 || image->samples == 16) {
@@ -844,32 +834,6 @@ transition_color_buffer(struct anv_cmd_buffer *cmd_buffer,
                           base_layer, layer_count,
                           ISL_AUX_OP_FAST_CLEAR, false);
       }
-      /* At this point, some elements of the CCS buffer may have the fast-clear
-       * bit-arrangement. As the user writes to a subresource, we need to have
-       * the associated CCS elements enter the ambiguated state. This enables
-       * reads (implicit or explicit) to reflect the user-written data instead
-       * of the clear color. The only time such elements will not change their
-       * state as described above, is in a final layout that doesn't have CCS
-       * enabled. In this case, we must force the associated CCS buffers of the
-       * specified range to enter the ambiguated state in advance.
-       */
-      if (image->samples == 1 &&
-          image->planes[plane].aux_usage != ISL_AUX_USAGE_CCS_E &&
-          final_layout != VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL) {
-         /* The CCS_D buffer may not be enabled in the final layout. Call this
-          * function again with a initial layout of COLOR_ATTACHMENT_OPTIMAL
-          * to perform a resolve.
-          */
-          anv_perf_warn(cmd_buffer->device->instance, image,
-                        "Performing an additional resolve for CCS_D layout "
-                        "transition. Consider always leaving it on or "
-                        "performing an ambiguation pass.");
-         transition_color_buffer(cmd_buffer, image, aspect,
-                                 base_level, level_count,
-                                 base_layer, layer_count,
-                                 VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL,
-                                 final_layout);
-      }
       return;
    }
 
-- 
2.5.0.400.gff86faf