[Mesa-dev] [PATCH 22/32] i965/miptree: Allow for accessing a CCS_E image as CCS_D

[Jason Ekstrand]

This requires us to start using the partial clear state.  It makes
things quite a bit more complicated but it's still a fairly
straightforward exercise in diagram following.
---
 src/mesa/drivers/dri/i965/intel_mipmap_tree.c | 36 +++++++++++++++++++++------
 1 file changed, 28 insertions(+), 8 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/intel_mipmap_tree.c b/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
index 68e0246..1bbf9a5 100644
--- a/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
+++ b/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
@@ -2196,12 +2196,26 @@ get_ccs_e_resolve_op(enum isl_aux_state aux_state,
                      enum isl_aux_usage aux_usage,
                      bool fast_clear_supported)
 {
-   const bool ccs_supported = aux_usage != ISL_AUX_USAGE_NONE;
+   /* CCS_E surfaces can be accessed as CCS_D if we're careful. */
+   assert(aux_usage == ISL_AUX_USAGE_NONE ||
+          aux_usage == ISL_AUX_USAGE_CCS_D ||
+          aux_usage == ISL_AUX_USAGE_CCS_E);
+
+   if (aux_usage == ISL_AUX_USAGE_CCS_D)
+      assert(fast_clear_supported);
 
    switch (aux_state) {
    case ISL_AUX_STATE_CLEAR:
+   case ISL_AUX_STATE_PARTIAL_CLEAR:
+      if (fast_clear_supported)
+         return BLORP_FAST_CLEAR_OP_NONE;
+      else if (aux_usage == ISL_AUX_USAGE_CCS_E)
+         return BLORP_FAST_CLEAR_OP_RESOLVE_PARTIAL;
+      else
+         return BLORP_FAST_CLEAR_OP_RESOLVE_FULL;
+
    case ISL_AUX_STATE_COMPRESSED_CLEAR:
-      if (!ccs_supported)
+      if (aux_usage != ISL_AUX_USAGE_CCS_E)
          return BLORP_FAST_CLEAR_OP_RESOLVE_FULL;
       else if (!fast_clear_supported)
          return BLORP_FAST_CLEAR_OP_RESOLVE_PARTIAL;
@@ -2209,7 +2223,7 @@ get_ccs_e_resolve_op(enum isl_aux_state aux_state,
          return BLORP_FAST_CLEAR_OP_NONE;
 
    case ISL_AUX_STATE_COMPRESSED_NO_CLEAR:
-      if (!ccs_supported)
+      if (aux_usage != ISL_AUX_USAGE_CCS_E)
          return BLORP_FAST_CLEAR_OP_RESOLVE_FULL;
       else
          return BLORP_FAST_CLEAR_OP_NONE;
@@ -2217,7 +2231,6 @@ get_ccs_e_resolve_op(enum isl_aux_state aux_state,
    case ISL_AUX_STATE_PASS_THROUGH:
       return BLORP_FAST_CLEAR_OP_NONE;
 
-   case ISL_AUX_STATE_PARTIAL_CLEAR:
    case ISL_AUX_STATE_RESOLVED:
    case ISL_AUX_STATE_AUX_INVALID:
       break;
@@ -2282,9 +2295,17 @@ intel_miptree_finish_ccs_write(struct brw_context *brw,
    if (mt->aux_usage == ISL_AUX_USAGE_CCS_E) {
       switch (aux_state) {
       case ISL_AUX_STATE_CLEAR:
-         assert(written_with_ccs);
-         intel_miptree_set_aux_state(brw, mt, level, layer, 1,
-                                     ISL_AUX_STATE_COMPRESSED_CLEAR);
+      case ISL_AUX_STATE_PARTIAL_CLEAR:
+         assert(aux_usage == ISL_AUX_USAGE_CCS_E ||
+                aux_usage == ISL_AUX_USAGE_CCS_D);
+
+         if (aux_usage == ISL_AUX_USAGE_CCS_E) {
+            intel_miptree_set_aux_state(brw, mt, level, layer, 1,
+                                        ISL_AUX_STATE_COMPRESSED_CLEAR);
+         } else if (aux_state != ISL_AUX_STATE_PARTIAL_CLEAR) {
+            intel_miptree_set_aux_state(brw, mt, level, layer, 1,
+                                        ISL_AUX_STATE_PARTIAL_CLEAR);
+         }
          break;
 
       case ISL_AUX_STATE_COMPRESSED_CLEAR:
@@ -2301,7 +2322,6 @@ intel_miptree_finish_ccs_write(struct brw_context *brw,
          }
          break;
 
-      case ISL_AUX_STATE_PARTIAL_CLEAR:
       case ISL_AUX_STATE_RESOLVED:
       case ISL_AUX_STATE_AUX_INVALID:
          unreachable("Invalid aux state for CCS_E");
-- 
2.5.0.400.gff86faf