libcamera: ipu3: Add support for a RAW still capture stream

Allow the RAW buffer cycling between CIO2 and IMGU to be memory copied
to a new FrameBuffer in a new RAW stream. This allows users to capture
the raw Bayer format coming from the sensor.

As the RAW frame is memory copied queueing requests with the
StillCaptureRaw stream might impact performance.

Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

src/libcamera/pipeline/ipu3/ipu3.cpp

@@ -33,6 +33,13 @@ LOG_DEFINE_CATEGORY(IPU3)
 
 class IPU3CameraData;
 
+static const std::map<uint32_t, PixelFormat> sensorMbusToPixel = {
+	{ MEDIA_BUS_FMT_SBGGR10_1X10, PixelFormat(DRM_FORMAT_SBGGR10, { IPU3_FORMAT_MOD_PACKED }) },
+	{ MEDIA_BUS_FMT_SGBRG10_1X10, PixelFormat(DRM_FORMAT_SGBRG10, { IPU3_FORMAT_MOD_PACKED }) },
+	{ MEDIA_BUS_FMT_SGRBG10_1X10, PixelFormat(DRM_FORMAT_SGRBG10, { IPU3_FORMAT_MOD_PACKED }) },
+	{ MEDIA_BUS_FMT_SRGGB10_1X10, PixelFormat(DRM_FORMAT_SRGGB10, { IPU3_FORMAT_MOD_PACKED }) },
+};
+
 class ImgUDevice
 {
 public:
@@ -140,11 +147,12 @@ class IPU3Stream : public Stream
 {
 public:
 	IPU3Stream()
-		: active_(false), device_(nullptr)
+		: active_(false), raw_(false), device_(nullptr)
 	{
 	}
 
 	bool active_;
+	bool raw_;
 	std::string name_;
 	ImgUDevice::ImgUOutput *device_;
 };
@@ -166,6 +174,7 @@ public:
 
 	IPU3Stream outStream_;
 	IPU3Stream vfStream_;
+	IPU3Stream rawStream_;
 };
 
 class IPU3CameraConfiguration : public CameraConfiguration
@@ -180,6 +189,7 @@ public:
 
 private:
 	static constexpr unsigned int IPU3_BUFFER_COUNT = 4;
+	static constexpr unsigned int IPU3_MAX_STREAMS = 3;
 
 	void adjustStream(StreamConfiguration &cfg, bool scale);
 
@@ -291,8 +301,6 @@ void IPU3CameraConfiguration::adjustStream(StreamConfiguration &cfg, bool scale)
 		cfg.size.width &= ~7;
 		cfg.size.height &= ~3;
 	}
-
-	cfg.bufferCount = IPU3_BUFFER_COUNT;
 }
 
 CameraConfiguration::Status IPU3CameraConfiguration::validate()
@@ -304,8 +312,8 @@ CameraConfiguration::Status IPU3CameraConfiguration::validate()
 		return Invalid;
 
 	/* Cap the number of entries to the available streams. */
-	if (config_.size() > 2) {
+	if (config_.size() > IPU3_MAX_STREAMS) {
-		config_.resize(2);
+		config_.resize(IPU3_MAX_STREAMS);
 		status = Adjusted;
 	}
 
@@ -345,6 +353,7 @@ CameraConfiguration::Status IPU3CameraConfiguration::validate()
 	std::set<const IPU3Stream *> availableStreams = {
 		&data_->outStream_,
 		&data_->vfStream_,
+		&data_->rawStream_,
 	};
 
 	streams_.clear();
@@ -356,7 +365,9 @@ CameraConfiguration::Status IPU3CameraConfiguration::validate()
 		const Size size = cfg.size;
 		const IPU3Stream *stream;
 
-		if (cfg.size == sensorFormat_.size)
+		if (cfg.pixelFormat.modifiers().count(IPU3_FORMAT_MOD_PACKED))
+			stream = &data_->rawStream_;
+		else if (cfg.size == sensorFormat_.size)
 			stream = &data_->outStream_;
 		else
 			stream = &data_->vfStream_;
@@ -367,8 +378,20 @@ CameraConfiguration::Status IPU3CameraConfiguration::validate()
 		LOG(IPU3, Debug)
 			<< "Assigned '" << stream->name_ << "' to stream " << i;
 
+		if (stream->raw_) {
+			const auto &itFormat =
+				sensorMbusToPixel.find(sensorFormat_.mbus_code);
+			if (itFormat == sensorMbusToPixel.end())
+				return Invalid;
+
+			cfg.pixelFormat = itFormat->second;
+			cfg.size = sensorFormat_.size;
+		} else {
 			bool scale = stream == &data_->vfStream_;
 			adjustStream(config_[i], scale);
+		}
+
+		cfg.bufferCount = IPU3_BUFFER_COUNT;
 
 		if (cfg.pixelFormat != pixelFormat || cfg.size != size) {
 			LOG(IPU3, Debug)
@@ -397,6 +420,7 @@ CameraConfiguration *PipelineHandlerIPU3::generateConfiguration(Camera *camera,
 	std::set<IPU3Stream *> streams = {
 		&data->outStream_,
 		&data->vfStream_,
+		&data->rawStream_,
 	};
 
 	config = new IPU3CameraConfiguration(camera, data);
@@ -438,6 +462,29 @@ CameraConfiguration *PipelineHandlerIPU3::generateConfiguration(Camera *camera,
 
 			break;
 
+		case StreamRole::StillCaptureRaw: {
+			if (streams.find(&data->rawStream_) == streams.end()) {
+				LOG(IPU3, Error)
+					<< "No stream available for requested role "
+					<< role;
+				break;
+			}
+
+			stream = &data->rawStream_;
+
+			cfg.size = data->cio2_.sensor_->resolution();
+
+			V4L2SubdeviceFormat sensorFormat =
+				data->cio2_.sensor_->getFormat({ MEDIA_BUS_FMT_SBGGR10_1X10,
+								 MEDIA_BUS_FMT_SGBRG10_1X10,
+								 MEDIA_BUS_FMT_SGRBG10_1X10,
+								 MEDIA_BUS_FMT_SRGGB10_1X10 },
+							       cfg.size);
+			cfg.pixelFormat =
+				sensorMbusToPixel.at(sensorFormat.mbus_code);
+			break;
+		}
+
 		case StreamRole::Viewfinder:
 		case StreamRole::VideoRecording: {
 			/*
@@ -535,6 +582,9 @@ int PipelineHandlerIPU3::configure(Camera *camera, CameraConfiguration *c)
 	/*
 	 * \todo: Enable links selectively based on the requested streams.
 	 * As of now, enable all links unconditionally.
+	 * \todo Don't configure the ImgU at all if we only have a single
+	 * stream which is for raw capture, in which case no buffers will
+	 * ever be queued to the ImgU.
 	 */
 	ret = data->imgu_->enableLinks(true);
 	if (ret)
@@ -571,6 +621,13 @@ int PipelineHandlerIPU3::configure(Camera *camera, CameraConfiguration *c)
 		stream->active_ = true;
 		cfg.setStream(stream);
 
+		/*
+		 * The RAW still capture stream just copies buffers from the
+		 * internal queue and doesn't need any specific configuration.
+		 */
+		if (stream->raw_)
+			continue;
+
 		ret = imgu->configureOutput(stream->device_, cfg);
 		if (ret)
 			return ret;
@@ -621,9 +678,15 @@ int PipelineHandlerIPU3::configure(Camera *camera, CameraConfiguration *c)
 int PipelineHandlerIPU3::exportFrameBuffers(Camera *camera, Stream *stream,
 					    std::vector<std::unique_ptr<FrameBuffer>> *buffers)
 {
+	IPU3CameraData *data = cameraData(camera);
 	IPU3Stream *ipu3stream = static_cast<IPU3Stream *>(stream);
-	V4L2VideoDevice *video = ipu3stream->device_->dev;
 	unsigned int count = stream->configuration().bufferCount;
+	V4L2VideoDevice *video;
+
+	if (ipu3stream->raw_)
+		video = data->cio2_.output_;
+	else
+		video = ipu3stream->device_->dev;
 
 	return video->exportBuffers(count, buffers);
 }
@@ -737,6 +800,10 @@ int PipelineHandlerIPU3::queueRequestDevice(Camera *camera, Request *request)
 		IPU3Stream *stream = static_cast<IPU3Stream *>(it.first);
 		buffer = it.second;
 
+		/* Skip raw streams, they are copied from the CIO2 buffer. */
+		if (stream->raw_)
+			continue;
+
 		int ret = stream->device_->dev->queueBuffer(buffer);
 		if (ret < 0)
 			error = ret;
@@ -831,6 +898,7 @@ int PipelineHandlerIPU3::registerCameras()
 		std::set<Stream *> streams = {
 			&data->outStream_,
 			&data->vfStream_,
+			&data->rawStream_,
 		};
 		CIO2Device *cio2 = &data->cio2_;
 
@@ -852,6 +920,8 @@ int PipelineHandlerIPU3::registerCameras()
 		data->outStream_.name_ = "output";
 		data->vfStream_.device_ = &data->imgu_->viewfinder_;
 		data->vfStream_.name_ = "viewfinder";
+		data->rawStream_.raw_ = true;
+		data->rawStream_.name_ = "raw";
 
 		/*
 		 * Connect video devices' 'bufferReady' signals to their
@@ -941,7 +1011,28 @@ void IPU3CameraData::cio2BufferReady(FrameBuffer *buffer)
 	if (buffer->metadata().status == FrameMetadata::FrameCancelled)
 		return;
 
+	Request *request = buffer->request();
+	FrameBuffer *raw = request->findBuffer(&rawStream_);
+
+	if (!raw) {
+		/* No RAW buffers present, just queue to IMGU. */
 		imgu_->input_->queueBuffer(buffer);
+		return;
+	}
+
+	/* RAW buffers present, special care is needed. */
+	if (request->buffers().size() > 1)
+		imgu_->input_->queueBuffer(buffer);
+
+	if (raw->copyFrom(buffer))
+		LOG(IPU3, Debug) << "Copy of FrameBuffer failed";
+
+	pipe_->completeBuffer(camera_, request, raw);
+
+	if (request->buffers().size() == 1) {
+		cio2_.putBuffer(buffer);
+		pipe_->completeRequest(camera_, request);
+	}
 }
 
 /* -----------------------------------------------------------------------------