[libcamera-devel] [PATCH v3 2/3] pipeline: raspberrypi: Add a Unicam dequeue timeout

[Laurent Pinchart]

On Tue, Apr 05, 2022 at 06:34:21PM +0300, Laurent Pinchart via libcamera-devel wrote:
> On Thu, Mar 31, 2022 at 02:35:57PM +0100, Kieran Bingham via libcamera-devel wrote:
> > Quoting Naushir Patuck via libcamera-devel (2022-03-29 12:29:28)
> > > Enable the V4L2VideoDevice dequeue timeout for the Unicam Image node, and
> > > connect the timeout signal to a slot in the pipeline handler. This slot will
> > > log a fatal error message informing the user of a possible hardware stall.
> > 
> > No longer a fatal error message.
> > 
> > > The timeout is calculated as 2x the maximum frame length possible for a given
> > > mode, returned by the IPA.
> 
> I mentioned in the review of v1 that we should probably increase the
> timeout (to 10 times the frame duration). That was based on the error
> message being fatal though, but maybe it's still good to avoid a short
> watchdog timeout ?
> 
> > > Signed-off-by: Naushir Patuck <naush at raspberrypi.com>
> > > ---
> > >  include/libcamera/ipa/raspberrypi.mojom           |  1 +
> > >  src/ipa/raspberrypi/raspberrypi.cpp               |  2 ++
> > >  .../pipeline/raspberrypi/raspberrypi.cpp          | 15 +++++++++++++++
> > >  3 files changed, 18 insertions(+)
> > > 
> > > diff --git a/include/libcamera/ipa/raspberrypi.mojom b/include/libcamera/ipa/raspberrypi.mojom
> > > index acd3cafe6c91..5a228b75cd2f 100644
> > > --- a/include/libcamera/ipa/raspberrypi.mojom
> > > +++ b/include/libcamera/ipa/raspberrypi.mojom
> > > @@ -41,6 +41,7 @@ struct IPAConfig {
> > >  struct StartConfig {
> > >         libcamera.ControlList controls;
> > >         int32 dropFrameCount;
> > > +       uint32 maxSensorFrameLengthMs;
> > >  };
> > >  
> > >  interface IPARPiInterface {
> > > diff --git a/src/ipa/raspberrypi/raspberrypi.cpp b/src/ipa/raspberrypi/raspberrypi.cpp
> > > index 1bf4e270b062..89767a9db471 100644
> > > --- a/src/ipa/raspberrypi/raspberrypi.cpp
> > > +++ b/src/ipa/raspberrypi/raspberrypi.cpp
> > > @@ -280,6 +280,8 @@ void IPARPi::start(const ControlList &controls, ipa::RPi::StartConfig *startConf
> > >         }
> > >  
> > >         startConfig->dropFrameCount = dropFrameCount_;
> > > +       const Duration maxSensorFrameDuration = mode_.max_frame_length * mode_.line_length;
> > > +       startConfig->maxSensorFrameLengthMs = maxSensorFrameDuration.get<std::milli>();
> > >  
> > >         firstStart_ = false;
> > >         lastRunTimestamp_ = 0;
> > > diff --git a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> > > index 8fd79be67988..93931aaf3b55 100644
> > > --- a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> > > +++ b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> > > @@ -208,6 +208,7 @@ public:
> > >         void setIspControls(const ControlList &controls);
> > >         void setDelayedControls(const ControlList &controls);
> > >         void setSensorControls(ControlList &controls);
> > > +       void unicamTimeout();
> > >  
> > >         /* bufferComplete signal handlers. */
> > >         void unicamBufferDequeue(FrameBuffer *buffer);
> > > @@ -1050,6 +1051,11 @@ int PipelineHandlerRPi::start(Camera *camera, const ControlList *controls)
> > >                 }
> > >         }
> > >  
> > > +       /* Set the dequeue timeout to 2x the maximum possible frame duration. */
> > > +       std::chrono::milliseconds msec(startConfig.maxSensorFrameLengthMs * 2);
> 
> s/msec/timeout/
> 
> > > +       data->unicam_[Unicam::Image].dev()->setDequeueTimeout(msec);
> > > +       LOG(RPI, Debug) << "Setting Unicam timeout to " << msec << " ms.";
> 
> I may have dropped this message, I'm not sure it helps much.
> 
> > > +
> > >         return 0;
> > >  }
> > >  
> > > @@ -1192,6 +1198,7 @@ int PipelineHandlerRPi::registerCamera(MediaDevice *unicam, MediaDevice *isp, Me
> > >         data->isp_[Isp::Stats] = RPi::Stream("ISP Stats", ispCapture3);
> > >  
> > >         /* Wire up all the buffer connections. */
> > > +       data->unicam_[Unicam::Image].dev()->dequeueTimeout.connect(data.get(), &RPiCameraData::unicamTimeout);
> > >         data->unicam_[Unicam::Image].dev()->frameStart.connect(data.get(), &RPiCameraData::frameStarted);
> > >         data->unicam_[Unicam::Image].dev()->bufferReady.connect(data.get(), &RPiCameraData::unicamBufferDequeue);
> > >         data->isp_[Isp::Input].dev()->bufferReady.connect(data.get(), &RPiCameraData::ispInputDequeue);
> > > @@ -1773,6 +1780,14 @@ void RPiCameraData::setSensorControls(ControlList &controls)
> > >         sensor_->setControls(&controls);
> > >  }
> > >  
> > > +void RPiCameraData::unicamTimeout()
> > > +{
> > > +       LOG(RPI, Error)
> > > +               << "Unicam has timed out!\n"
> > > +                  "Please check that your camera sensor connector is attached securely.\n"
> > 
> > The '\n' should probably be std::endl ... but I don't think that makes a
> > big difference here?
> 
> It would still be good, for consistency.

Also, a \n in the middle of the log may be a bit messy, as the next
lines will not have the right prefixes. We could add some sort of
utils::logEndl that would do the right thing (but that's out of scope
for this series), or maybe shorten the message to one line here, or even
print multiple messages ?

> > Both of those could be fixed while applying, there's nothing complex
> > there.
> > 
> > Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> 
> Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> 
> > > +                  "Alternatively, try another cable and/or sensor.";
> > > +}
> > > +
> > >  void RPiCameraData::unicamBufferDequeue(FrameBuffer *buffer)
> > >  {
> > >         RPi::Stream *stream = nullptr;
> 
> -- 
> Regards,
> 
> Laurent Pinchart

-- 
Regards,

Laurent Pinchart