From: jsg <jsg@openbsd.org>
Date: Mon, 1 Aug 2022 16:11:08 +0000 (+0000)
Subject: drm/amd/display: Fix surface optimization regression on Carrizo
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=008b458bdf256ebb8fd490fddc36f780733b7ac5;p=openbsd

drm/amd/display: Fix surface optimization regression on Carrizo

From Nicholas Kazlauskas
c2b484d784c8dfc3eb62fd4f9ff11515b6e78e19 in linux 5.15.y/5.15.58
62e5a7e2333a9f5395f6a9db766b7b06c949fe7a in mainline linux
---

diff --git a/sys/dev/pci/drm/amd/display/dc/core/amdgpu_dc.c b/sys/dev/pci/drm/amd/display/dc/core/amdgpu_dc.c
index 46bef173992..1bde9d4e82d 100644
--- a/sys/dev/pci/drm/amd/display/dc/core/amdgpu_dc.c
+++ b/sys/dev/pci/drm/amd/display/dc/core/amdgpu_dc.c
@@ -2979,8 +2979,13 @@ void dc_commit_updates_for_stream(struct dc *dc,
 			if (new_pipe->plane_state && new_pipe->plane_state != old_pipe->plane_state)
 				new_pipe->plane_state->force_full_update = true;
 		}
-	} else if (update_type == UPDATE_TYPE_FAST) {
-		/* Previous frame finished and HW is ready for optimization. */
+	} else if (update_type == UPDATE_TYPE_FAST && dc_ctx->dce_version >= DCE_VERSION_MAX) {
+		/*
+		 * Previous frame finished and HW is ready for optimization.
+		 *
+		 * Only relevant for DCN behavior where we can guarantee the optimization
+		 * is safe to apply - retain the legacy behavior for DCE.
+		 */
 		dc_post_update_surfaces_to_stream(dc);
 	}
 
@@ -3039,6 +3044,12 @@ void dc_commit_updates_for_stream(struct dc *dc,
 		}
 	}
 
+	/* Legacy optimization path for DCE. */
+	if (update_type >= UPDATE_TYPE_FULL && dc_ctx->dce_version < DCE_VERSION_MAX) {
+		dc_post_update_surfaces_to_stream(dc);
+		TRACE_DCE_CLOCK_STATE(&context->bw_ctx.bw.dce);
+	}
+
 	return;
 
 }