Re: [PATCH 2/9] drm/msm/dpu: add real wait_for_commit_done()

Sean Paul
2019-08-29T13:05:06Z

On Tue, Aug 27, 2019 at 02:33:32PM -0700, Rob Clark wrote:
> From: Rob Clark <robdclark@chromium.org>
>
> Just waiting for next vblank isn't ideal.. we should really be looking
> at the hw FLUSH register value to know if there is still an in-progress
> flush without stalling unnecessarily when there is no pending flush.
>
> Signed-off-by: Rob Clark <robdclark@chromium.org>

Reviewed-by: Sean Paul <sean@poorly.run>

> ---
> .../drm/msm/disp/dpu1/dpu_encoder_phys_vid.c | 22 ++++++++++++++++++-
> 1 file changed, 21 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_vid.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_vid.c
> index 737fe963a490..7c73b09894f0 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_vid.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_vid.c
> @@ -526,6 +526,26 @@ static int dpu_encoder_phys_vid_wait_for_vblank(
> return _dpu_encoder_phys_vid_wait_for_vblank(phys_enc, true);
> }
>
> +static int dpu_encoder_phys_vid_wait_for_commit_done(
> + struct dpu_encoder_phys *phys_enc)
> +{
> + struct dpu_hw_ctl *hw_ctl = phys_enc->hw_ctl;
> + int ret;
> +
> + if (!hw_ctl)
> + return 0;
> +
> + ret = wait_event_timeout(phys_enc->pending_kickoff_wq,
> + (hw_ctl->ops.get_flush_register(hw_ctl) == 0),
> + msecs_to_jiffies(50));
> + if (ret <= 0) {
> + DPU_ERROR("vblank timeout\n");
> + return -ETIMEDOUT;
> + }
> +
> + return 0;
> +}
> +
> static void dpu_encoder_phys_vid_prepare_for_kickoff(
> struct dpu_encoder_phys *phys_enc)
> {
> @@ -676,7 +696,7 @@ static void dpu_encoder_phys_vid_init_ops(struct dpu_encoder_phys_ops *ops)
> ops->destroy = dpu_encoder_phys_vid_destroy;
> ops->get_hw_resources = dpu_encoder_phys_vid_get_hw_resources;
> ops->control_vblank_irq = dpu_encoder_phys_vid_control_vblank_irq;
> - ops->wait_for_commit_done = dpu_encoder_phys_vid_wait_for_vblank;
> + ops->wait_for_commit_done = dpu_encoder_phys_vid_wait_for_commit_done;
> ops->wait_for_vblank = dpu_encoder_phys_vid_wait_for_vblank;
> ops->wait_for_tx_complete = dpu_encoder_phys_vid_wait_for_vblank;
> ops->irq_control = dpu_encoder_phys_vid_irq_control;
> --
> 2.21.0
>

--
Sean Paul, Software Engineer, Google / Chromium OS