[Mesa-stable] [PATCH] radv: adjust the VGT workaround for prim restart on GFX9

[Samuel Pitoiset]

WD_SWITCH_ON_EOP seems to be the only workaround that fixes
the GPU hangs with Yakuza and The Evil Within on Vega. I don't
like as it might decrease geometry performance as pointed out
by Marek, but I don't know how to implement a better one.

Cc: mesa-stable at lists.freedesktop.org
Signed-off-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
---
 src/amd/vulkan/radv_pipeline.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/amd/vulkan/radv_pipeline.c b/src/amd/vulkan/radv_pipeline.c
index 426b417e172..2256b2c58e9 100644
--- a/src/amd/vulkan/radv_pipeline.c
+++ b/src/amd/vulkan/radv_pipeline.c
@@ -3412,14 +3412,23 @@ radv_compute_ia_multi_vgt_param_helpers(struct radv_pipeline *pipeline,
 	}
 
 	/* Workaround for a VGT hang when strip primitive types are used with
-	 * primitive restart.
+	 * primitive restart. This fixes GPU hangs with Yakuza and The Evil
+	 * Within, at least. Not sure if we can implement a better workaround.
 	 */
 	if (pipeline->graphics.prim_restart_enable &&
 	    (prim == V_008958_DI_PT_LINESTRIP ||
 	     prim == V_008958_DI_PT_TRISTRIP ||
 	     prim == V_008958_DI_PT_LINESTRIP_ADJ ||
 	     prim == V_008958_DI_PT_TRISTRIP_ADJ)) {
-		ia_multi_vgt_param.partial_vs_wave = true;
+		if (device->physical_device->rad_info.chip_class >= GFX9) {
+			/* XXX: This might decrease geometry performance by 2x,
+			 * but this appears to be the only workaround that
+			 * fixes the GPU hang.
+			 */
+			ia_multi_vgt_param.wd_switch_on_eop = true;
+		} else {
+			ia_multi_vgt_param.partial_vs_wave = true;
+		}
 	}
 
 	ia_multi_vgt_param.base =
-- 
2.19.1