ilo: add slice clear value

It is needed for 3DSTATE_CLEAR_PARAMS, and can also be used to track what
value the slice has been cleared to.

1 files changed, 31 insertions, 0 deletions

diff --git a/src/gallium/drivers/ilo/ilo_blit.c b/src/gallium/drivers/ilo/ilo_blit.c
index 74bb3554235..ad304c7109a 100644
--- a/src/gallium/drivers/ilo/ilo_blit.c
+++ b/src/gallium/drivers/ilo/ilo_blit.c
@@ -163,10 +163,26 @@ ilo_blit_resolve_slices_for_hiz(struct ilo_context *ilo,
        * When ILO_TEXTURE_RENDER_WRITE is set, there can be no reader.  We
        * need to perform a HiZ Buffer Resolve in case the resource was
        * previously written by another writer, unless this is a clear.
+       *
+       * When slices have different clear values, we perform a Depth Buffer
+       * Resolve on all slices not sharing the clear value of the first slice.
+       * After resolving, those slices do not use 3DSTATE_CLEAR_PARAMS and can
+       * be made to have the same clear value as the first slice does.  This
+       * way,
+       *
+       *  - 3DSTATE_CLEAR_PARAMS can be set to the clear value of any slice
+       *  - we will not resolve unnecessarily next time this function is
+       *    called
+       *
+       * Since slice clear value is the value the slice is cleared to when
+       * ILO_TEXTURE_CLEAR is set, the bit needs to be unset.
        */
       assert(!(resolve_flags & (other_writers | any_reader)));
 
       if (!(resolve_flags & ILO_TEXTURE_CLEAR)) {
+         bool set_clear_value = false;
+         uint32_t first_clear_value;
+
          for (i = 0; i < num_slices; i++) {
             const struct ilo_texture_slice *slice =
                ilo_texture_get_slice(tex, level, first_slice + i);
@@ -175,6 +191,21 @@ ilo_blit_resolve_slices_for_hiz(struct ilo_context *ilo,
                ilo_blitter_rectlist_resolve_hiz(ilo->blitter,
                      res, level, first_slice + i);
             }
+            else if (i == 0) {
+               first_clear_value = slice->clear_value;
+            }
+            else if (slice->clear_value != first_clear_value &&
+                     (slice->flags & ILO_TEXTURE_RENDER_WRITE)) {
+               ilo_blitter_rectlist_resolve_z(ilo->blitter,
+                     res, level, first_slice + i);
+               set_clear_value = true;
+            }
+         }
+
+         if (set_clear_value) {
+            /* ILO_TEXTURE_CLEAR will be cleared later */
+            ilo_texture_set_slice_clear_value(tex, level,
+                  first_slice, num_slices, first_clear_value);
          }
       }
    }