drm/msm/dpu: unwind async commit handling

It attempted to avoid fps drops in the presence of cursor updates.  But
it is racing, and can result in hw updates after flush before vblank,
which leads to underruns.

Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Sean Paul <sean@poorly.run>
Signed-off-by: Rob Clark <robdclark@chromium.org>

1 files changed, 13 insertions, 26 deletions

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
index feb2a45de96a..090c304adfef 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
@@ -1423,8 +1423,7 @@ static void dpu_encoder_off_work(struct work_struct *work)
  * extra_flush_bits: Additional bit mask to include in flush trigger
  */
 static void _dpu_encoder_trigger_flush(struct drm_encoder *drm_enc,
-		struct dpu_encoder_phys *phys, uint32_t extra_flush_bits,
-		bool async)
+		struct dpu_encoder_phys *phys, uint32_t extra_flush_bits)
 {
 	struct dpu_hw_ctl *ctl;
 	int pending_kickoff_cnt;
@@ -1441,10 +1440,7 @@ static void _dpu_encoder_trigger_flush(struct drm_encoder *drm_enc,
 		return;
 	}
 
-	if (!async)
-		pending_kickoff_cnt = dpu_encoder_phys_inc_pending(phys);
-	else
-		pending_kickoff_cnt = atomic_read(&phys->pending_kickoff_cnt);
+	pending_kickoff_cnt = dpu_encoder_phys_inc_pending(phys);
 
 	if (extra_flush_bits && ctl->ops.update_pending_flush)
 		ctl->ops.update_pending_flush(ctl, extra_flush_bits);
@@ -1555,8 +1551,7 @@ static void dpu_encoder_helper_hw_reset(struct dpu_encoder_phys *phys_enc)
  *	a time.
  * dpu_enc: Pointer to virtual encoder structure
  */
-static void _dpu_encoder_kickoff_phys(struct dpu_encoder_virt *dpu_enc,
-				      bool async)
+static void _dpu_encoder_kickoff_phys(struct dpu_encoder_virt *dpu_enc)
 {
 	struct dpu_hw_ctl *ctl;
 	uint32_t i, pending_flush;
@@ -1583,13 +1578,12 @@ static void _dpu_encoder_kickoff_phys(struct dpu_encoder_virt *dpu_enc,
 		 * for async commits. So don't set this for async, since it'll
 		 * roll over to the next commit.
 		 */
-		if (!async && phys->split_role != ENC_ROLE_SLAVE)
+		if (phys->split_role != ENC_ROLE_SLAVE)
 			set_bit(i, dpu_enc->frame_busy_mask);
 
 		if (!phys->ops.needs_single_flush ||
 				!phys->ops.needs_single_flush(phys))
-			_dpu_encoder_trigger_flush(&dpu_enc->base, phys, 0x0,
-						   async);
+			_dpu_encoder_trigger_flush(&dpu_enc->base, phys, 0x0);
 		else if (ctl->ops.get_pending_flush)
 			pending_flush |= ctl->ops.get_pending_flush(ctl);
 	}
@@ -1599,7 +1593,7 @@ static void _dpu_encoder_kickoff_phys(struct dpu_encoder_virt *dpu_enc,
 		_dpu_encoder_trigger_flush(
 				&dpu_enc->base,
 				dpu_enc->cur_master,
-				pending_flush, async);
+				pending_flush);
 	}
 
 	_dpu_encoder_trigger_start(dpu_enc->cur_master);
@@ -1817,11 +1811,12 @@ void dpu_encoder_prepare_for_kickoff(struct drm_encoder *drm_enc)
 	}
 }
 
-void dpu_encoder_kickoff(struct drm_encoder *drm_enc, bool async)
+void dpu_encoder_kickoff(struct drm_encoder *drm_enc)
 {
 	struct dpu_encoder_virt *dpu_enc;
 	struct dpu_encoder_phys *phys;
 	ktime_t wakeup_time;
+	unsigned long timeout_ms;
 	unsigned int i;
 
 	DPU_ATRACE_BEGIN("encoder_kickoff");
@@ -1829,23 +1824,15 @@ void dpu_encoder_kickoff(struct drm_encoder *drm_enc, bool async)
 
 	trace_dpu_enc_kickoff(DRMID(drm_enc));
 
-	/*
-	 * Asynchronous frames don't handle FRAME_DONE events. As such, they
-	 * shouldn't enable the frame_done watchdog since it will always time
-	 * out.
-	 */
-	if (!async) {
-		unsigned long timeout_ms;
-		timeout_ms = DPU_ENCODER_FRAME_DONE_TIMEOUT_FRAMES * 1000 /
+	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));
-	}
+	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, async);
+	_dpu_encoder_kickoff_phys(dpu_enc);
 
 	/* allow phys encs to handle any post-kickoff business */
 	for (i = 0; i < dpu_enc->num_phys_encs; i++) {