[Mesa-dev] [PATCH 25/27] i965: Use partial resolves for CCS buffers being scanned out

[Ben Widawsky]

From: Ben Widawsky <ben at bwidawsk.net>

On Gen9 hardware, the display engine is able to scanout a compressed
framebuffer by providing an offset to auxiliary compression information.
Unfortunately, the hardware is incapable of doing the same thing for the
fast clear color.

To mitigate this, the hardware introduced a new resolve type called a
partial resolve. The partial resolve will only do a resolve of the fast
clear color and leave the rest of the compressed data alone.

This patch enables using this resolve type for cases where the
framebuffer will be passed along to the kernel for display.

Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
---
 src/mesa/drivers/dri/i965/brw_context.c       | 3 ++-
 src/mesa/drivers/dri/i965/intel_mipmap_tree.c | 4 ++--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_context.c b/src/mesa/drivers/dri/i965/brw_context.c
index cfd7a54..2bc2e94 100644
--- a/src/mesa/drivers/dri/i965/brw_context.c
+++ b/src/mesa/drivers/dri/i965/brw_context.c
@@ -1359,7 +1359,8 @@ intel_resolve_for_dri2_flush(struct brw_context *brw,
       if (rb->mt->num_samples <= 1) {
          assert(rb->mt_layer == 0 && rb->mt_level == 0 &&
                 rb->layer_count == 1);
-         intel_miptree_resolve_color(brw, rb->mt, 0, 0, 1, 0);
+         intel_miptree_resolve_color(brw, rb->mt, 0, 0, 1,
+                                     INTEL_RESOLVE_HINT_CLEAR_COLOR);
       } else {
          intel_renderbuffer_downsample(brw, rb);
       }
diff --git a/src/mesa/drivers/dri/i965/intel_mipmap_tree.c b/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
index dd71a06..b79de08 100644
--- a/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
+++ b/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
@@ -2399,8 +2399,8 @@ intel_miptree_make_shareable(struct brw_context *brw,
    assert(mt->msaa_layout == INTEL_MSAA_LAYOUT_NONE || mt->num_samples <= 1);
 
    if (mt->mcs_buf) {
-      intel_miptree_all_slices_resolve_color(brw, mt, 0);
-      mt->no_ccs = true;
+      intel_miptree_all_slices_resolve_color(brw, mt,
+                                             INTEL_RESOLVE_HINT_CLEAR_COLOR);
    }
 }
 
-- 
2.10.2