[PATCH v3 13/23] drm/msm/dpu: Add CWB to msm_display_topology

[Jessica Zhang]

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/msm_drv.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 d53e986eee5467d78aa3b4cc2bc59a954942cdea..5af506a66d5b5cce172e66bfea85b483a8fa1c70 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
@@ -1176,6 +1176,8 @@ 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
 	 *
@@ -1187,9 +1189,16 @@ 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 96c80cf9f6ad60cef9fb5fda38179b8ef4f5de4a..04df3056d75a799ad4bdc87d6a9c97acdb990323 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
@@ -371,8 +371,14 @@ 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/msm_drv.h b/drivers/gpu/drm/msm/msm_drv.h
index 2e28a13446366caae48ff6291d5f88db06de645e..34a378cecfe0eef45262592c9f9e8e4234f37a29 100644
--- a/drivers/gpu/drm/msm/msm_drv.h
+++ b/drivers/gpu/drm/msm/msm_drv.h
@@ -1,5 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
+ * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.
  * Copyright (c) 2016-2018, The Linux Foundation. All rights reserved.
  * Copyright (C) 2013 Red Hat
  * Author: Rob Clark <robdclark at gmail.com>
@@ -84,6 +85,7 @@ struct msm_display_topology {
 	u32 num_dspp;
 	u32 num_dsc;
 	bool needs_cdm;
+	bool cwb_enabled;
 };
 
 /* Commit/Event thread specific structure */

-- 
2.34.1