Re: [Freedreno] [DPU PATCH v2 1/2] drm/msm/dsi: check video mode engine status before waiting

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi Sean

Thanks for reviewing.

Reply inline.

On 2018-04-16 10:07, Sean Paul wrote:
On Fri, Apr 13, 2018 at 03:04:48PM -0700, abhinavk@xxxxxxxxxxxxxx wrote:
On 2018-04-13 14:10, abhinavk@xxxxxxxxxxxxxx wrote:
> Hi Sean
>
> Thanks for the review.
>
> Reply inline.
>
> On 2018-04-13 13:26, Sean Paul wrote:
> > On Tue, Apr 10, 2018 at 06:54:06PM -0700, Abhinav Kumar wrote:
> > > Make sure the video mode engine is on before waiting
> > > for the video done interrupt.
> > >
> > > Otherwise it leads to silent timeouts increasing display
> > > turn ON time.
> > >
> > > Changes in v2:
> > > - Replace pr_err with dev_err
> > > - Changed error message
> > >
> > > Signed-off-by: Abhinav Kumar <abhinavk@xxxxxxxxxxxxxx>
> > > ---
> > >  drivers/gpu/drm/msm/dsi/dsi_host.c | 15 +++++++++++----
> > >  1 file changed, 11 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c
> > > b/drivers/gpu/drm/msm/dsi/dsi_host.c
> > > index 7a03a94..5b7b290 100644
> > > --- a/drivers/gpu/drm/msm/dsi/dsi_host.c
> > > +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
> > > @@ -173,6 +173,7 @@ struct msm_dsi_host {
> > >
> > >  	bool registered;
> > >  	bool power_on;
> > > +	bool enabled;
> > >  	int irq;
> > >  };
> > >
> > > @@ -986,13 +987,19 @@ static void dsi_set_tx_power_mode(int
> > > mode, struct msm_dsi_host *msm_host)
> > >
> > >  static void dsi_wait4video_done(struct msm_dsi_host *msm_host)
> > >  {
> > > +	u32 ret = 0;
> > > +	struct device *dev = &msm_host->pdev->dev;
> > > +
> > >  	dsi_intr_ctrl(msm_host, DSI_IRQ_MASK_VIDEO_DONE, 1);
> > >
> > >  	reinit_completion(&msm_host->video_comp);
> > >
> > > -	wait_for_completion_timeout(&msm_host->video_comp,
> > > +	ret = wait_for_completion_timeout(&msm_host->video_comp,
> > >  			msecs_to_jiffies(70));
> > >
> > > +	if (ret <= 0)
> > > +		dev_err(dev, "wait for video done timed out\n");
> > > +
> > >  	dsi_intr_ctrl(msm_host, DSI_IRQ_MASK_VIDEO_DONE, 0);
> > >  }
> > >
> > > @@ -1001,7 +1008,7 @@ static void dsi_wait4video_eng_busy(struct
> > > msm_dsi_host *msm_host)
> > >  	if (!(msm_host->mode_flags & MIPI_DSI_MODE_VIDEO))
> > >  		return;
> > >
> > > -	if (msm_host->power_on) {
> > > +	if (msm_host->power_on && msm_host->enabled) {
> > >  		dsi_wait4video_done(msm_host);
> > >  		/* delay 4 ms to skip BLLP */
> > >  		usleep_range(2000, 4000);
> > > @@ -2203,7 +2210,7 @@ int msm_dsi_host_enable(struct
> > > mipi_dsi_host *host)
> > >  	 *	pm_runtime_put_autosuspend(&msm_host->pdev->dev);
> > >  	 * }
> > >  	 */
> > > -
> > > +	msm_host->enabled = true;
> > >  	return 0;
> > >  }
> > >
> > > @@ -2219,7 +2226,7 @@ int msm_dsi_host_disable(struct
> > > mipi_dsi_host *host)
> > >  	 * Reset to disable video engine so that we can send off cmd.
> > >  	 */
> > >  	dsi_sw_reset(msm_host);
> > > -
> > > +	msm_host->enabled = false;
> >
> > This should go at the start of the function. Also, it's unclear from
> > this patch,
> > but I assume this is protected by a lock?
> >
> > Sean
> [Abhinav] Yes, will move this to the start.
> No, there is no lock here but at this point doesnt need one.
> The reason is that, this variable will be written to and read by the
> same process
> (suspend thread OR resume thread which sends the panel ON/OFF commands).
> If we decide to expose other interfaces to send commands like debugfs
> or sysfs and
> introduce more threads, we will add the locking.
[Abhinav] Correction to my prev comment, we do have the msm_host->cmd_mutex
which will
ensure this entire process is protected. That should suffice.

Ok, thanks for confirming. Could you also please split this patch into the wait4video_done ret fix and the ->enabled addition? The 2 seem mostly unrelated.

Sean

They are quite related actually. So we were not able to catch this earlier because the wait was silently timing out. Hence along with the fix I wanted
to change the ret to add the error log because such condition should not
happen with the ->enabled fix. To signify that I clubbed them together.
I can split them, if this still feels unrelated.

> >
> >
> > >  	return 0;
> > >  }
> > >
> > > --
> > > The Qualcomm Innovation Center, Inc. is a member of the Code
> > > Aurora Forum,
> > > a Linux Foundation Collaborative Project
> > >
> > > _______________________________________________
> > > Freedreno mailing list
> > > Freedreno@xxxxxxxxxxxxxxxxxxxxx
> > > https://lists.freedesktop.org/mailman/listinfo/freedreno
> --
> To unsubscribe from this list: send the line "unsubscribe linux-arm-msm"
> in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/dri-devel




[Index of Archives]     [Linux DRI Users]     [Linux Intel Graphics]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]
  Powered by Linux