[Mesa-dev] [PATCH 1/4] i965: Emit SNB write cache flush W/A from brw_emit_pipe_control_flush.

[Francisco Jerez]

Shouldn't cause any functional changes at this point, but we have
forgotten to apply this workaround several times in the past, make
sure it doesn't happen again.
---
 src/mesa/drivers/dri/i965/brw_misc_state.c   |  9 ---------
 src/mesa/drivers/dri/i965/brw_pipe_control.c | 21 +++++++++++----------
 src/mesa/drivers/dri/i965/intel_fbo.c        |  8 --------
 src/mesa/drivers/dri/i965/intel_tex.c        |  8 --------
 4 files changed, 11 insertions(+), 35 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_misc_state.c b/src/mesa/drivers/dri/i965/brw_misc_state.c
index 690c2f6..c3d341f 100644
--- a/src/mesa/drivers/dri/i965/brw_misc_state.c
+++ b/src/mesa/drivers/dri/i965/brw_misc_state.c
@@ -925,15 +925,6 @@ brw_emit_select_pipeline(struct brw_context *brw, enum brw_pipeline pipeline)
       const unsigned dc_flush =
          brw->gen >= 7 ? PIPE_CONTROL_DATA_CACHE_FLUSH : 0;
 
-      if (brw->gen == 6) {
-         /* Hardware workaround: SNB B-Spec says:
-          *
-          *   Before a PIPE_CONTROL with Write Cache Flush Enable = 1, a
-          *   PIPE_CONTROL with any non-zero post-sync-op is required.
-          */
-         brw_emit_post_sync_nonzero_flush(brw);
-      }
-
       brw_emit_pipe_control_flush(brw,
                                   PIPE_CONTROL_RENDER_TARGET_FLUSH |
                                   PIPE_CONTROL_DEPTH_CACHE_FLUSH |
diff --git a/src/mesa/drivers/dri/i965/brw_pipe_control.c b/src/mesa/drivers/dri/i965/brw_pipe_control.c
index 4672efd..586355d 100644
--- a/src/mesa/drivers/dri/i965/brw_pipe_control.c
+++ b/src/mesa/drivers/dri/i965/brw_pipe_control.c
@@ -109,6 +109,17 @@ brw_emit_pipe_control_flush(struct brw_context *brw, uint32_t flags)
       OUT_BATCH(0);
       ADVANCE_BATCH();
    } else if (brw->gen >= 6) {
+      if (brw->gen == 6 &&
+          (flags & PIPE_CONTROL_RENDER_TARGET_FLUSH)) {
+         /* Hardware workaround: SNB B-Spec says:
+          *
+          *   [Dev-SNB{W/A}]: Before a PIPE_CONTROL with Write Cache Flush
+          *   Enable = 1, a PIPE_CONTROL with any non-zero post-sync-op is
+          *   required.
+          */
+         brw_emit_post_sync_nonzero_flush(brw);
+      }
+
       flags |= gen7_cs_stall_every_four_pipe_controls(brw, flags);
 
       BEGIN_BATCH(5);
@@ -325,16 +336,6 @@ brw_emit_mi_flush(struct brw_context *brw)
                   PIPE_CONTROL_VF_CACHE_INVALIDATE |
                   PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE |
                   PIPE_CONTROL_CS_STALL;
-
-         if (brw->gen == 6) {
-            /* Hardware workaround: SNB B-Spec says:
-             *
-             * [Dev-SNB{W/A}]: Before a PIPE_CONTROL with Write Cache
-             * Flush Enable =1, a PIPE_CONTROL with any non-zero
-             * post-sync-op is required.
-             */
-            brw_emit_post_sync_nonzero_flush(brw);
-         }
       }
       brw_emit_pipe_control_flush(brw, flags);
    }
diff --git a/src/mesa/drivers/dri/i965/intel_fbo.c b/src/mesa/drivers/dri/i965/intel_fbo.c
index 939f9a0..707a9d2 100644
--- a/src/mesa/drivers/dri/i965/intel_fbo.c
+++ b/src/mesa/drivers/dri/i965/intel_fbo.c
@@ -1061,14 +1061,6 @@ brw_render_cache_set_check_flush(struct brw_context *brw, drm_intel_bo *bo)
       return;
 
    if (brw->gen >= 6) {
-      if (brw->gen == 6) {
-         /* [Dev-SNB{W/A}]: Before a PIPE_CONTROL with Write Cache
-          * Flush Enable = 1, a PIPE_CONTROL with any non-zero
-          * post-sync-op is required.
-          */
-         brw_emit_post_sync_nonzero_flush(brw);
-      }
-
       brw_emit_pipe_control_flush(brw,
                                   PIPE_CONTROL_DEPTH_CACHE_FLUSH |
                                   PIPE_CONTROL_RENDER_TARGET_FLUSH |
diff --git a/src/mesa/drivers/dri/i965/intel_tex.c b/src/mesa/drivers/dri/i965/intel_tex.c
index a802d5a..8c32fe3 100644
--- a/src/mesa/drivers/dri/i965/intel_tex.c
+++ b/src/mesa/drivers/dri/i965/intel_tex.c
@@ -364,14 +364,6 @@ intel_texture_barrier(struct gl_context *ctx)
    struct brw_context *brw = brw_context(ctx);
 
    if (brw->gen >= 6) {
-      if (brw->gen == 6) {
-         /* [Dev-SNB{W/A}]: Before a PIPE_CONTROL with Write Cache
-          * Flush Enable = 1, a PIPE_CONTROL with any non-zero
-          * post-sync-op is required.
-          */
-         brw_emit_post_sync_nonzero_flush(brw);
-      }
-
       brw_emit_pipe_control_flush(brw,
                                   PIPE_CONTROL_DEPTH_CACHE_FLUSH |
                                   PIPE_CONTROL_RENDER_TARGET_FLUSH |
-- 
2.9.0