drm/msm/dpu: Start frame done timer after encoder kickoff

Starting the frame done timer before the encoder is finished kicking off
can lead to unnecessary frame done timeouts when the device is
experiencing heavy load (ex. when debug logs are enabled).

Thus, create a separate API for starting the encoder frame done timer and
call it after the encoder kickoff is finished

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/637502/
Link: https://lore.kernel.org/r/20250214-concurrent-wb-v6-11-a44c293cf422@quicinc.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c

@@ -999,8 +999,10 @@ void dpu_crtc_commit_kickoff(struct drm_crtc *crtc)
 
 	dpu_vbif_clear_errors(dpu_kms);
 
-	drm_for_each_encoder_mask(encoder, crtc->dev, crtc->state->encoder_mask)
+	drm_for_each_encoder_mask(encoder, crtc->dev, crtc->state->encoder_mask) {
 		dpu_encoder_kickoff(encoder);
+		dpu_encoder_start_frame_done_timer(encoder);
+	}
 
 	reinit_completion(&dpu_crtc->frame_done_comp);
 

drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c

@@ -2095,6 +2095,25 @@ bool dpu_encoder_is_valid_for_commit(struct drm_encoder *drm_enc)
 	return true;
 }
 
+/**
+ * dpu_encoder_start_frame_done_timer - Start the encoder frame done timer
+ * @drm_enc: Pointer to drm encoder structure
+ */
+void dpu_encoder_start_frame_done_timer(struct drm_encoder *drm_enc)
+{
+	struct dpu_encoder_virt *dpu_enc;
+	unsigned long timeout_ms;
+
+	dpu_enc = to_dpu_encoder_virt(drm_enc);
+	timeout_ms = DPU_ENCODER_FRAME_DONE_TIMEOUT_FRAMES * 1000 /
+			drm_mode_vrefresh(&drm_enc->crtc->state->adjusted_mode);
+
+	atomic_set(&dpu_enc->frame_done_timeout_ms, timeout_ms);
+	mod_timer(&dpu_enc->frame_done_timer,
+			jiffies + msecs_to_jiffies(timeout_ms));
+
+}
+
 /**
  * dpu_encoder_kickoff - trigger a double buffer flip of the ctl path
  *	(i.e. ctl flush and start) immediately.
@@ -2104,21 +2123,13 @@ void dpu_encoder_kickoff(struct drm_encoder *drm_enc)
 {
 	struct dpu_encoder_virt *dpu_enc;
 	struct dpu_encoder_phys *phys;
-	unsigned long timeout_ms;
 	unsigned int i;
 
 	DPU_ATRACE_BEGIN("encoder_kickoff");
 	dpu_enc = to_dpu_encoder_virt(drm_enc);
 
 	trace_dpu_enc_kickoff(DRMID(drm_enc));
 
-	timeout_ms = DPU_ENCODER_FRAME_DONE_TIMEOUT_FRAMES * 1000 /
-			drm_mode_vrefresh(&drm_enc->crtc->state->adjusted_mode);
-
-	atomic_set(&dpu_enc->frame_done_timeout_ms, timeout_ms);
-	mod_timer(&dpu_enc->frame_done_timer,
-			jiffies + msecs_to_jiffies(timeout_ms));
-
 	/* All phys encs are ready to go, trigger the kickoff */
 	_dpu_encoder_kickoff_phys(dpu_enc);
 

drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
- * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2022-2024 Qualcomm Innovation Center, Inc. All rights reserved.
  * Copyright (c) 2015-2018, The Linux Foundation. All rights reserved.
  * Copyright (C) 2013 Red Hat
  * Author: Rob Clark <robdclark@gmail.com>
@@ -95,4 +95,5 @@ void dpu_encoder_cleanup_wb_job(struct drm_encoder *drm_enc,
 
 bool dpu_encoder_is_valid_for_commit(struct drm_encoder *drm_enc);
 
+void dpu_encoder_start_frame_done_timer(struct drm_encoder *drm_enc);
 #endif /* __DPU_ENCODER_H__ */