[Mesa-dev] [PATCH] RFC: Workaround for gen9 hw astc5x5 sampler bug

[Topi Pohjolainen]

This is just drafting some thoughts and only compile tested.

CC: "Rogovin, Kevin" <kevin.rogovin at intel.com>
---
 src/mesa/drivers/dri/i965/brw_blorp.c   |  8 +++++
 src/mesa/drivers/dri/i965/brw_context.h | 10 ++++++
 src/mesa/drivers/dri/i965/brw_draw.c    | 54 ++++++++++++++++++++++++++++++++-
 3 files changed, 71 insertions(+), 1 deletion(-)

diff --git a/src/mesa/drivers/dri/i965/brw_blorp.c b/src/mesa/drivers/dri/i965/brw_blorp.c
index 680121b6ab..b3f84ab8ca 100644
--- a/src/mesa/drivers/dri/i965/brw_blorp.c
+++ b/src/mesa/drivers/dri/i965/brw_blorp.c
@@ -186,11 +186,19 @@ blorp_surf_for_miptree(struct brw_context *brw,
          surf->aux_addr.buffer = mt->hiz_buf->bo;
          surf->aux_addr.offset = mt->hiz_buf->offset;
       }
+
+      if (!is_render_target && brw->screen->devinfo.gen == 9)
+         gen9_astc5x5_sampler_wa(brw, GEN9_ASTC5X5_WA_TEX_TYPE_AUX);
    } else {
       surf->aux_addr = (struct blorp_address) {
          .buffer = NULL,
       };
       memset(&surf->clear_color, 0, sizeof(surf->clear_color));
+
+      if (!is_render_target && brw->screen->devinfo.gen == 9 &&
+          (mt->format == MESA_FORMAT_RGBA_ASTC_5x5 ||
+           mt->format == MESA_FORMAT_SRGB8_ALPHA8_ASTC_5x5))
+         gen9_astc5x5_sampler_wa(brw, GEN9_ASTC5X5_WA_TEX_TYPE_ASTC5x5);
    }
    assert((surf->aux_usage == ISL_AUX_USAGE_NONE) ==
           (surf->aux_addr.buffer == NULL));
diff --git a/src/mesa/drivers/dri/i965/brw_context.h b/src/mesa/drivers/dri/i965/brw_context.h
index 0670483806..44602c23c0 100644
--- a/src/mesa/drivers/dri/i965/brw_context.h
+++ b/src/mesa/drivers/dri/i965/brw_context.h
@@ -165,6 +165,11 @@ enum brw_cache_id {
    BRW_MAX_CACHE
 };
 
+enum gen9_astc5x5_wa_tex_type {
+   GEN9_ASTC5X5_WA_TEX_TYPE_ASTC5x5 = 1 << 0,
+   GEN9_ASTC5X5_WA_TEX_TYPE_AUX     = 1 << 1,
+};
+
 enum brw_state_id {
    /* brw_cache_ids must come first - see brw_program_cache.c */
    BRW_STATE_URB_FENCE = BRW_MAX_CACHE,
@@ -1262,6 +1267,8 @@ struct brw_context
     */
    bool draw_aux_buffer_disabled[MAX_DRAW_BUFFERS];
 
+   enum gen9_astc5x5_wa_tex_type gen9_sampler_wa_tex_mask;
+
    __DRIcontext *driContext;
    struct intel_screen *screen;
 };
@@ -1286,6 +1293,9 @@ void intel_update_renderbuffers(__DRIcontext *context,
                                 __DRIdrawable *drawable);
 void intel_prepare_render(struct brw_context *brw);
 
+void gen9_astc5x5_sampler_wa(struct brw_context *brw,
+                             enum gen9_astc5x5_wa_tex_type curr_mask);
+
 void brw_predraw_resolve_inputs(struct brw_context *brw, bool rendering);
 
 void intel_resolve_for_dri2_flush(struct brw_context *brw,
diff --git a/src/mesa/drivers/dri/i965/brw_draw.c b/src/mesa/drivers/dri/i965/brw_draw.c
index 7e29dcfd4e..929f806eb3 100644
--- a/src/mesa/drivers/dri/i965/brw_draw.c
+++ b/src/mesa/drivers/dri/i965/brw_draw.c
@@ -371,6 +371,50 @@ intel_disable_rb_aux_buffer(struct brw_context *brw,
    return found;
 }
 
+static enum gen9_astc5x5_wa_tex_type
+gen9_astc5x5_wa_get_tex_mask(const struct brw_context *brw)
+{
+   enum gen9_astc5x5_wa_tex_type mask = 0;
+   const struct gl_context *ctx = &brw->ctx;
+   const struct intel_texture_object *tex_obj;
+
+   const int maxEnabledUnit = ctx->Texture._MaxEnabledTexImageUnit;
+   for (int i = 0; i <= maxEnabledUnit; i++) {
+      if (!ctx->Texture.Unit[i]._Current)
+	 continue;
+      tex_obj = intel_texture_object(ctx->Texture.Unit[i]._Current);
+      if (!tex_obj || !tex_obj->mt)
+	 continue;
+
+      if (tex_obj->mt->aux_usage != ISL_AUX_USAGE_NONE)
+         mask |= GEN9_ASTC5X5_WA_TEX_TYPE_ASTC5x5;
+
+      if (tex_obj->_Format == MESA_FORMAT_RGBA_ASTC_5x5 ||
+          tex_obj->_Format == MESA_FORMAT_SRGB8_ALPHA8_ASTC_5x5)
+         mask |= GEN9_ASTC5X5_WA_TEX_TYPE_AUX;
+   }
+
+   return mask;
+}
+
+/* TODO: Do we actually need this both ways: astc5x5 followed by aux
+ *       and vice-versa? Or is only one direction problematic?
+ */
+void
+gen9_astc5x5_sampler_wa(struct brw_context *brw,
+                        enum gen9_astc5x5_wa_tex_type curr_mask)
+{
+   if ((brw->gen9_sampler_wa_tex_mask & GEN9_ASTC5X5_WA_TEX_TYPE_ASTC5x5) &&
+       (curr_mask & GEN9_ASTC5X5_WA_TEX_TYPE_AUX))
+      brw_emit_pipe_control_flush(brw, PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE);
+
+   if ((brw->gen9_sampler_wa_tex_mask & GEN9_ASTC5X5_WA_TEX_TYPE_AUX) &&
+       (curr_mask & GEN9_ASTC5X5_WA_TEX_TYPE_ASTC5x5))
+      brw_emit_pipe_control_flush(brw, PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE);
+
+   brw->gen9_sampler_wa_tex_mask = curr_mask;
+}
+
 /**
  * \brief Resolve buffers before drawing.
  *
@@ -383,6 +427,12 @@ brw_predraw_resolve_inputs(struct brw_context *brw, bool rendering)
    struct gl_context *ctx = &brw->ctx;
    struct intel_texture_object *tex_obj;
 
+   const enum gen9_astc5x5_wa_tex_type curr_wa_mask =
+      (brw->screen->devinfo.gen == 9) ? gen9_astc5x5_wa_get_tex_mask(brw) : 0;
+
+   if (brw->screen->devinfo.gen == 9)
+      gen9_astc5x5_sampler_wa(brw, curr_wa_mask);
+
    memset(brw->draw_aux_buffer_disabled, 0,
           sizeof(brw->draw_aux_buffer_disabled));
 
@@ -413,6 +463,8 @@ brw_predraw_resolve_inputs(struct brw_context *brw, bool rendering)
          num_layers = INTEL_REMAINING_LAYERS;
       }
 
+      const bool sampler_wa_disable_aux =
+         curr_wa_mask & GEN9_ASTC5X5_WA_TEX_TYPE_ASTC5x5;
       const bool disable_aux = rendering &&
          intel_disable_rb_aux_buffer(brw, tex_obj->mt, min_level, num_levels,
                                      "for sampling");
@@ -420,7 +472,7 @@ brw_predraw_resolve_inputs(struct brw_context *brw, bool rendering)
       intel_miptree_prepare_texture(brw, tex_obj->mt, view_format,
                                     min_level, num_levels,
                                     min_layer, num_layers,
-                                    disable_aux);
+                                    disable_aux || sampler_wa_disable_aux);
 
       brw_cache_flush_for_read(brw, tex_obj->mt->bo);
 
-- 
2.14.1