[Mesa-dev] [PATCH 06/23] i965/gen9: Add buffer layout representing lossless compression

[Topi Pohjolainen]

Skylake introduces compression support also for the single-sampled
color buffers. Similarly to the multi-sampled case the color buffer
will be associated with an auxiliary surface tracking the
compression state.

Signed-off-by: Topi Pohjolainen <topi.pohjolainen at intel.com>
---
 src/mesa/drivers/dri/i965/brw_blorp_blit.cpp  | 15 +++++++++++++++
 src/mesa/drivers/dri/i965/brw_tex_layout.c    |  2 ++
 src/mesa/drivers/dri/i965/intel_mipmap_tree.c |  4 ++++
 src/mesa/drivers/dri/i965/intel_mipmap_tree.h |  9 +++++++++
 4 files changed, 30 insertions(+)

diff --git a/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp b/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp
index c7cb394..9ca33b4 100644
--- a/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp
+++ b/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp
@@ -1162,6 +1162,11 @@ brw_blorp_blit_program::encode_msaa(unsigned num_samples,
       SWAP_XY_AND_XPYP();
       s_is_zero = true;
       break;
+   case INTEL_MSAA_LAYOUT_CSS:
+      /* This is impossible combination, blorp is supported only on
+       * gen < 8 while CSS is only supported from gen 9 onwards.
+       */
+      unreachable("Blorp does not support lossless compression");
    }
 }
 
@@ -1239,6 +1244,11 @@ brw_blorp_blit_program::decode_msaa(unsigned num_samples,
       s_is_zero = false;
       SWAP_XY_AND_XPYP();
       break;
+   case INTEL_MSAA_LAYOUT_CSS:
+      /* This is impossible combination, blorp is supported only on
+       * gen < 8 while CSS is only supported from gen 9 onwards.
+       */
+      unreachable("Blorp does not support lossless compression");
    }
 }
 
@@ -1642,6 +1652,11 @@ brw_blorp_blit_program::texel_fetch(struct brw_reg dst)
          texture_lookup(dst, SHADER_OPCODE_TXF, gen7_ld_args,
                         ARRAY_SIZE(gen7_ld_args));
          break;
+      case INTEL_MSAA_LAYOUT_CSS:
+         /* This is impossible combination, blorp is supported only on
+          * gen < 8 while CSS is only supported from gen 9 onwards.
+          */
+	 unreachable("Blorp does not support lossless compression");
       }
       break;
    default:
diff --git a/src/mesa/drivers/dri/i965/brw_tex_layout.c b/src/mesa/drivers/dri/i965/brw_tex_layout.c
index a294829..2366bfa 100644
--- a/src/mesa/drivers/dri/i965/brw_tex_layout.c
+++ b/src/mesa/drivers/dri/i965/brw_tex_layout.c
@@ -686,6 +686,8 @@ intel_miptree_set_total_width_height(struct brw_context *brw,
       case INTEL_MSAA_LAYOUT_CMS:
          brw_miptree_layout_texture_array(brw, mt);
          break;
+      case INTEL_MSAA_LAYOUT_CSS:
+         assert(brw->gen >= 9);
       case INTEL_MSAA_LAYOUT_NONE:
       case INTEL_MSAA_LAYOUT_IMS:
          if (gen9_use_linear_1d_layout(brw, mt))
diff --git a/src/mesa/drivers/dri/i965/intel_mipmap_tree.c b/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
index d40a529..fe525c3 100644
--- a/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
+++ b/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
@@ -460,6 +460,8 @@ intel_miptree_create_layout(struct brw_context *brw,
       case INTEL_MSAA_LAYOUT_CMS:
          mt->array_layout = ALL_SLICES_AT_EACH_LOD;
          break;
+      case INTEL_MSAA_LAYOUT_CSS:
+	 unreachable("Lossless compression is only support for gen9+");
       }
    }
 
@@ -1051,6 +1053,8 @@ intel_miptree_match_image(struct intel_mipmap_tree *mt,
       case INTEL_MSAA_LAYOUT_CMS:
          level_depth /= mt->num_samples;
          break;
+      case INTEL_MSAA_LAYOUT_CSS:
+         unreachable("Lossless compression is only for single-sampled");
       }
    }
 
diff --git a/src/mesa/drivers/dri/i965/intel_mipmap_tree.h b/src/mesa/drivers/dri/i965/intel_mipmap_tree.h
index 64f73ea..0970fd5 100644
--- a/src/mesa/drivers/dri/i965/intel_mipmap_tree.h
+++ b/src/mesa/drivers/dri/i965/intel_mipmap_tree.h
@@ -198,6 +198,15 @@ enum intel_msaa_layout
     * @see PRM section "Compressed Multisampled Surfaces"
     */
    INTEL_MSAA_LAYOUT_CMS,
+
+   /**
+    * Compressed Singlesample Surface. The color values are stored in one
+    * slice and an auxiliary buffer is used to track compression state just
+    * as in the Compressed Multisample case.
+    *
+    * @see section "Lossless Compression"
+    */
+   INTEL_MSAA_LAYOUT_CSS,
 };
 
 
-- 
2.5.0