Mesa (main): freedreno/a6xx: Sync TFB BO access against prior TFB writes.

[GitLab Mirror]

Module: Mesa
Branch: main
Commit: e6776148c103fa965752a0a866b688a8d9a84bef
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=e6776148c103fa965752a0a866b688a8d9a84bef

Author: Emma Anholt <emma at anholt.net>
Date:   Wed Aug 18 13:30:57 2021 -0700

freedreno/a6xx: Sync TFB BO access against prior TFB writes.

CTS draw_indirect usage of TFB output was flaking due to the TFB writes
possibly not having completed.  Since GL TFB doesn't require any other
barrier between TFB and use of the BO (as seen by the CTS not emitting any
memory barrier), we have to do it ourselves.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/12457>

---

 src/freedreno/ci/deqp-freedreno-a630-fails.txt          |  4 ----
 src/gallium/drivers/freedreno/a6xx/fd6_emit.c           | 17 +++++++++++++++++
 .../freedreno/ci/piglit-freedreno-a630-fails.txt        |  1 -
 3 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/src/freedreno/ci/deqp-freedreno-a630-fails.txt b/src/freedreno/ci/deqp-freedreno-a630-fails.txt
index 767bb04783b..18325d68824 100644
--- a/src/freedreno/ci/deqp-freedreno-a630-fails.txt
+++ b/src/freedreno/ci/deqp-freedreno-a630-fails.txt
@@ -28,10 +28,6 @@ KHR-GLES31.core.gpu_shader5.fma_precision_vec4,Fail
 # "Got red: 1, expected 0.00392157, at (1, 0)"
 KHR-GLES31.core.compute_shader.resource-image,Fail
 
-# "(x,y)= (0,0). Color RGBA(0,0,0,1) is different than expected RGBA(0.1,0.2,0.3,1)"
-KHR-GLES31.core.draw_indirect.advanced-twoPass-transformFeedback-arrays,Fail
-KHR-GLES31.core.draw_indirect.advanced-twoPass-transformFeedback-elements,Fail
-
 # Lots of errors like "[279] Check failed. Received: [3,0,0,2] instead of: [5,0,0,2]"
 KHR-GLES31.core.geometry_shader.layered_framebuffer.depth_support,Fail
 
diff --git a/src/gallium/drivers/freedreno/a6xx/fd6_emit.c b/src/gallium/drivers/freedreno/a6xx/fd6_emit.c
index 3c4716ff68f..bd9b39a71eb 100644
--- a/src/gallium/drivers/freedreno/a6xx/fd6_emit.c
+++ b/src/gallium/drivers/freedreno/a6xx/fd6_emit.c
@@ -927,6 +927,23 @@ fd6_emit_streamout(struct fd_ringbuffer *ring, struct fd6_emit *emit) assert_dt
       }
    }
 
+   /* Make sure that any use of our TFB outputs (indirect draw source or shader
+    * UBO reads) comes after the TFB output is written.  From the GL 4.6 core
+    * spec:
+    *
+    *     "Buffers should not be bound or in use for both transform feedback and
+    *      other purposes in the GL.  Specifically, if a buffer object is
+    *      simultaneously bound to a transform feedback buffer binding point
+    *      and elsewhere in the GL, any writes to or reads from the buffer
+    *      generate undefined values."
+    *
+    * So we idle whenever SO buffers change.  Note that this function is called
+    * on every draw with TFB enabled, so check the dirty flag for the buffers
+    * themselves.
+    */
+   if (ctx->dirty & FD_DIRTY_STREAMOUT)
+      fd_wfi(ctx->batch, ring);
+
    ctx->last.streamout_mask = emit->streamout_mask;
 }
 
diff --git a/src/gallium/drivers/freedreno/ci/piglit-freedreno-a630-fails.txt b/src/gallium/drivers/freedreno/ci/piglit-freedreno-a630-fails.txt
index 4e85532d401..61c1a5b0cda 100644
--- a/src/gallium/drivers/freedreno/ci/piglit-freedreno-a630-fails.txt
+++ b/src/gallium/drivers/freedreno/ci/piglit-freedreno-a630-fails.txt
@@ -311,7 +311,6 @@ spec at ext_texture_srgb@texwrap formats-s3tc bordercolor-swizzled at GL_COMPRESSED_SR
 spec at ext_texture_srgb@texwrap formats-s3tc bordercolor-swizzled at GL_COMPRESSED_SRGB_S3TC_DXT1_EXT- swizzled- border color only,Fail
 spec at ext_texture_srgb@texwrap formats-s3tc bordercolor-swizzled at GL_COMPRESSED_SRGB- swizzled- border color only,Fail
 spec at ext_transform_feedback@geometry-shaders-basic,Fail
-spec at ext_transform_feedback@immediate-reuse-index-buffer,Fail
 spec at ext_transform_feedback@intervening-read prims_generated,Fail
 spec at ext_transform_feedback@intervening-read prims_generated use_gs,Fail
 spec at ext_transform_feedback@overflow-edge-cases,Fail