Mesa (master): radeonsi: fix a GS hang on VI

[Marek Olšák]

Module: Mesa
Branch: master
Commit: 13e69805ea6a3aa0ec80c2b2430ae4da05c6b1ae
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=13e69805ea6a3aa0ec80c2b2430ae4da05c6b1ae

Author: Marek Olšák <marek.olsak at amd.com>
Date:   Fri Oct  2 19:21:54 2015 +0200

radeonsi: fix a GS hang on VI

Broken by one of the cleanups: 0d46c3bc9d09b376d74f7399e1a2d1b0a923640b
Not applicable to stable.

Reviewed-by: Alex Deucher <alexander.deucher at amd.com>

---

 src/gallium/drivers/radeonsi/si_pipe.h          |    1 +
 src/gallium/drivers/radeonsi/si_state_shaders.c |   18 ++++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/src/gallium/drivers/radeonsi/si_pipe.h b/src/gallium/drivers/radeonsi/si_pipe.h
index 3ff4b46..2abd5b5 100644
--- a/src/gallium/drivers/radeonsi/si_pipe.h
+++ b/src/gallium/drivers/radeonsi/si_pipe.h
@@ -192,6 +192,7 @@ struct si_context {
 
 	/* Precomputed states. */
 	struct si_pm4_state		*init_config;
+	bool				init_config_has_vgt_flush;
 	struct si_pm4_state		*vgt_shader_config[4];
 	/* With rasterizer discard, there doesn't have to be a pixel shader.
 	 * In that case, we bind this one: */
diff --git a/src/gallium/drivers/radeonsi/si_state_shaders.c b/src/gallium/drivers/radeonsi/si_state_shaders.c
index 77c585f..f673388 100644
--- a/src/gallium/drivers/radeonsi/si_state_shaders.c
+++ b/src/gallium/drivers/radeonsi/si_state_shaders.c
@@ -1136,6 +1136,20 @@ static void si_emit_spi_ps_input(struct si_context *sctx, struct r600_atom *atom
 				  sctx->force_persample_interp);
 }
 
+/**
+ * Writing CONFIG or UCONFIG VGT registers requires VGT_FLUSH before that.
+ */
+static void si_init_config_add_vgt_flush(struct si_context *sctx)
+{
+	if (sctx->init_config_has_vgt_flush)
+		return;
+
+	si_pm4_cmd_begin(sctx->init_config, PKT3_EVENT_WRITE);
+	si_pm4_cmd_add(sctx->init_config, EVENT_TYPE(V_028A90_VGT_FLUSH) | EVENT_INDEX(0));
+	si_pm4_cmd_end(sctx->init_config, false);
+	sctx->init_config_has_vgt_flush = true;
+}
+
 /* Initialize state related to ESGS / GSVS ring buffers */
 static void si_init_gs_rings(struct si_context *sctx)
 {
@@ -1156,6 +1170,8 @@ static void si_init_gs_rings(struct si_context *sctx)
 		return;
 	}
 
+	si_init_config_add_vgt_flush(sctx);
+
 	/* Append these registers to the init config state. */
 	if (sctx->b.chip_class >= CIK) {
 		if (sctx->b.chip_class >= VI) {
@@ -1402,6 +1418,8 @@ static void si_init_tess_factor_ring(struct si_context *sctx)
 
 	assert(((sctx->tf_ring->width0 / 4) & C_030938_SIZE) == 0);
 
+	si_init_config_add_vgt_flush(sctx);
+
 	/* Append these registers to the init config state. */
 	if (sctx->b.chip_class >= CIK) {
 		si_pm4_set_reg(sctx->init_config, R_030938_VGT_TF_RING_SIZE,