[PATCH v4 15/25] drm/msm/dpu: Add CWB to msm_display_topology

Jessica Zhang quic_jesszhan at quicinc.com
Tue Dec 17 00:43:26 UTC 2024


Add the cwb_enabled flag to msm_display topology and adjust the toplogy
to account for concurrent writeback

Signed-off-by: Jessica Zhang <quic_jesszhan at quicinc.com>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 11 ++++++++++-
 drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c   | 10 ++++++++--
 drivers/gpu/drm/msm/disp/dpu1/dpu_rm.h   |  2 ++
 3 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
index b4bfded3d53025853cee112ca598533ece290318..b063c8fe4c0594772d84401fa56c9c21afc0ad18 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
@@ -1198,6 +1198,8 @@ static struct msm_display_topology dpu_crtc_get_topology(
 		dpu_encoder_update_topology(drm_enc, &topology, crtc_state->state,
 					    &crtc_state->adjusted_mode);
 
+	topology.cwb_enabled = drm_crtc_in_clone_mode(crtc_state);
+
 	/*
 	 * Datapath topology selection
 	 *
@@ -1209,9 +1211,16 @@ static struct msm_display_topology dpu_crtc_get_topology(
 	 * 2 LM, 1 INTF (stream merge to support high resolution interfaces)
 	 *
 	 * Add dspps to the reservation requirements if ctm is requested
+	 *
+	 * Only hardcode num_lm to 2 for cases where num_intf == 2 and CWB is not
+	 * enabled. This is because in cases where CWB is enabled, num_intf will
+	 * count both the WB and real-time phys encoders.
+	 *
+	 * For non-DSC CWB usecases, have the num_lm be decided by the
+	 * (mode->hdisplay > MAX_HDISPLAY_SPLIT) check.
 	 */
 
-	if (topology.num_intf == 2)
+	if (topology.num_intf == 2 && !topology.cwb_enabled)
 		topology.num_lm = 2;
 	else if (topology.num_dsc == 2)
 		topology.num_lm = 2;
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
index b763ef19f4c60ae8a35df6a6ffb19e8411bc63f8..85adaf256b2c705d2d7df378b6ffc0e578f52bc3 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
@@ -382,8 +382,14 @@ static int _dpu_rm_reserve_ctls(
 	int i = 0, j, num_ctls;
 	bool needs_split_display;
 
-	/* each hw_intf needs its own hw_ctrl to program its control path */
-	num_ctls = top->num_intf;
+	/*
+	 * For non-CWB mode, each hw_intf needs its own hw_ctl to program its
+	 * control path. Hardcode num_ctls to 1 if CWB is enabled
+	 */
+	if (top->cwb_enabled)
+		num_ctls = 1;
+	else
+		num_ctls = top->num_intf;
 
 	needs_split_display = _dpu_rm_needs_split_display(top);
 
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.h
index b061dfdab52e04ab7d777e912a30173273cb3db7..12db21a2403ec6930894c36a58e898c5d94c2568 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.h
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.h
@@ -46,6 +46,7 @@ struct dpu_rm {
  * @num_dspp:     number of dspp blocks used
  * @num_dsc:      number of Display Stream Compression (DSC) blocks used
  * @needs_cdm:    indicates whether cdm block is needed for this display topology
+ * @cwb_enabled:  indicates whether CWB is enabled for this display topology
  */
 struct msm_display_topology {
 	u32 num_lm;
@@ -53,6 +54,7 @@ struct msm_display_topology {
 	u32 num_dspp;
 	u32 num_dsc;
 	bool needs_cdm;
+	bool cwb_enabled;
 };
 
 int dpu_rm_init(struct drm_device *dev,

-- 
2.34.1



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