[v4,10/13] drm/msm/disp/dpu1: Add support for DSC in topology

Commit Message

Vinod Koul Feb. 10, 2022, 6:37 a.m. UTC

For DSC to work we typically need a 2,2,1 configuration. This should
suffice for resolutions up to 4k. For more resolutions like 8k this won't
work.

Also, it is better to use 2 LMs and DSC instances as half width results
in lesser power consumption as compared to single LM, DSC at full width.

The panel has been tested only with 2,2,1 configuration, so for
now we blindly create 2,2,1 topology when DSC is enabled

Co-developed-by: Abhinav Kumar <[e-mail]>
Signed-off-by: Abhinav Kumar <[e-mail]>
Signed-off-by: Vinod Koul <[e-mail]>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 13 +++++++++++++
 drivers/gpu/drm/msm/msm_drv.h               |  2 ++
 2 files changed, 15 insertions(+)

Patch

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
index 95a7bf362e81..13ccb7b3cce5 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
@@ -574,8 +574,21 @@  static struct msm_display_topology dpu_encoder_get_topology(
 	topology.num_enc = 0;
 	topology.num_intf = intf_count;
 
+	if (dpu_enc->dsc) {
+		/* In case of Display Stream Compression DSC, we would use
+		 * 2 encoders, 2 line mixers and 1 interface
+		 * this is power optimal and can drive up to (including) 4k
+		 * screens
+		 */
+		topology.num_enc = 2;
+		topology.num_dsc = 2;
+		topology.num_intf = 1;
+		topology.num_lm = 2;
+	}
+
 	return topology;
 }
+
 static int dpu_encoder_virt_atomic_check(
 		struct drm_encoder *drm_enc,
 		struct drm_crtc_state *crtc_state,
diff --git a/drivers/gpu/drm/msm/msm_drv.h b/drivers/gpu/drm/msm/msm_drv.h
index 6425a42e997c..994d895d1a47 100644
--- a/drivers/gpu/drm/msm/msm_drv.h
+++ b/drivers/gpu/drm/msm/msm_drv.h
@@ -103,12 +103,14 @@  enum msm_event_wait {
  * @num_enc:      number of compression encoder blocks used
  * @num_intf:     number of interfaces the panel is mounted on
  * @num_dspp:     number of dspp blocks used
+ * @num_dsc:      number of Display Stream Compression (DSC) blocks used
  */
 struct msm_display_topology {
 	u32 num_lm;
 	u32 num_enc;
 	u32 num_intf;
 	u32 num_dspp;
+	u32 num_dsc;
 };
 
 /**