[PATCH 09/21] drm/msm/dpu: request more mixer for 4K+ DSC case

[Jun Nie]

request more mixer for the case that hdisplay exceeding 4096
and DSC enabled.

Signed-off-by: Jun Nie <jun.nie at linaro.org>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 24 ++++++++++++++++++++----
 1 file changed, 20 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
index 05b203be2a9bc..33cfd94badaba 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
@@ -59,6 +59,7 @@
 #define IDLE_SHORT_TIMEOUT	1
 
 #define MAX_HDISPLAY_SPLIT 1080
+#define MAX_HDISPLAY_DSC_SPLIT 2560
 
 /* timeout in frames waiting for frame done */
 #define DPU_ENCODER_FRAME_DONE_TIMEOUT_FRAMES 5
@@ -588,15 +589,19 @@ static struct msm_display_topology dpu_encoder_get_topology(
 
 	/* Datapath topology selection
 	 *
-	 * Dual display
+	 * Dual display without DSC
 	 * 2 LM, 2 INTF ( Split display using 2 interfaces)
 	 *
+	 * Dual display with DSC
+	 * 4 LM, 2 INTF ( Split display using 2 interfaces)
+	 *
 	 * Single display
 	 * 1 LM, 1 INTF
 	 * 2 LM, 1 INTF (stream merge to support high resolution interfaces)
 	 *
 	 * Add dspps to the reservation requirements if ctm is requested
 	 */
+
 	if (intf_count == 2)
 		topology.num_lm = 2;
 	else if (!dpu_kms->catalog->caps->has_3d_merge)
@@ -615,10 +620,21 @@ static struct msm_display_topology dpu_encoder_get_topology(
 		 * 2 DSC encoders, 2 layer mixers and 1 interface
 		 * this is power optimal and can drive up to (including) 4k
 		 * screens
+		 * But for dual display with hdisplay exceeding 4096, we need
+		 * 4 layer mixer. Because DSC has a max width of 2048 and
+		 * a single plane can only be used by one mixer pair
 		 */
-		topology.num_dsc = 2;
-		topology.num_lm = 2;
-		topology.num_intf = 1;
+
+		if (intf_count == 2 &&
+		    mode->hdisplay > MAX_HDISPLAY_DSC_SPLIT) {
+			topology.num_dsc = 4;
+			topology.num_lm = 4;
+			topology.num_intf = 2;
+		} else {
+			topology.num_dsc = 2;
+			topology.num_lm = 2;
+			topology.num_intf = 1;
+		}
 	}
 
 	return topology;

-- 
2.34.1