[libcamera-devel] [PATCH v4 6/7] pipeline: ipa: raspberrypi: Use IPA cookies

[Naushir Patuck]

Pass an IPA cookie from the pipeline handler to the IPA and eventually back to
the pipeline handler through the setDelayedControls signal. This cookie is used
to index the RPiController::Metadata object to be used for the frame.

The IPA cookie is then returned from DelayedControls when the frame with the
applied controls has been returned from the sensor, and eventually passed back
to the IPA from the signalIspPrepare signal.

Signed-off-by: Naushir Patuck <naush at raspberrypi.com>
Reviewed-by: David Plowman <david.plowman at raspberrypi.com>
Tested-by: David Plowman <david.plowman at raspberrypi.com>
---
 include/libcamera/ipa/raspberrypi.mojom       |  4 +++-
 src/ipa/raspberrypi/raspberrypi.cpp           | 12 +++++++-----
 .../pipeline/raspberrypi/raspberrypi.cpp      | 19 +++++++++++++------
 3 files changed, 23 insertions(+), 12 deletions(-)

diff --git a/include/libcamera/ipa/raspberrypi.mojom b/include/libcamera/ipa/raspberrypi.mojom
index 40f78d9e3b3f..bb5abd895262 100644
--- a/include/libcamera/ipa/raspberrypi.mojom
+++ b/include/libcamera/ipa/raspberrypi.mojom
@@ -37,6 +37,8 @@ struct ISPConfig {
 	uint32 bayerBufferId;
 	bool embeddedBufferPresent;
 	libcamera.ControlList controls;
+	uint32 ipaCookie;
+	uint32 delayCookie;
 };
 
 struct IPAConfig {
@@ -137,5 +139,5 @@ interface IPARPiEventInterface {
 	runIsp(uint32 bufferId);
 	embeddedComplete(uint32 bufferId);
 	setIspControls(libcamera.ControlList controls);
-	setDelayedControls(libcamera.ControlList controls);
+	setDelayedControls(libcamera.ControlList controls, uint32 delayCookie);
 };
diff --git a/src/ipa/raspberrypi/raspberrypi.cpp b/src/ipa/raspberrypi/raspberrypi.cpp
index 9e7792f5dfbe..aed8f68aded9 100644
--- a/src/ipa/raspberrypi/raspberrypi.cpp
+++ b/src/ipa/raspberrypi/raspberrypi.cpp
@@ -168,6 +168,7 @@ private:
 	RPiController::Controller controller_;
 	std::array<RPiController::Metadata, numMetadataContexts> rpiMetadata_;
 	unsigned int metadataIdx_;
+	unsigned int lastMetadataIdx_;
 
 	/*
 	 * We count frames to decide if the frame must be hidden (e.g. from
@@ -324,7 +325,6 @@ void IPARPi::start(const ControlList &controls, StartConfig *startConfig)
 
 	firstStart_ = false;
 	lastRunTimestamp_ = 0;
-	metadataIdx_ = 0;
 }
 
 void IPARPi::setMode(const IPACameraSensorInfo &sensorInfo)
@@ -535,6 +535,8 @@ void IPARPi::signalIspPrepare(const ISPConfig &data)
 	 * avoid running the control algos for a few frames in case
 	 * they are "unreliable".
 	 */
+	lastMetadataIdx_ = metadataIdx_;
+	metadataIdx_ = data.ipaCookie % rpiMetadata_.size();
 	prepareISP(data);
 	frameCount_++;
 
@@ -1011,11 +1013,10 @@ void IPARPi::returnEmbeddedBuffer(unsigned int bufferId)
 void IPARPi::prepareISP(const ISPConfig &data)
 {
 	int64_t frameTimestamp = data.controls.get(controls::SensorTimestamp).value_or(0);
-	RPiController::Metadata lastMetadata;
 	RPiController::Metadata &rpiMetadata = rpiMetadata_[metadataIdx_];
 	Span<uint8_t> embeddedBuffer;
 
-	lastMetadata = std::move(rpiMetadata);
+	rpiMetadata.clear();
 	fillDeviceStatus(data.controls);
 
 	if (data.embeddedBufferPresent) {
@@ -1048,7 +1049,8 @@ void IPARPi::prepareISP(const ISPConfig &data)
 		 * current frame, or any other bits of metadata that were added
 		 * in helper_->Prepare().
 		 */
-		rpiMetadata.merge(lastMetadata);
+		RPiController::Metadata &lastMetadata = rpiMetadata_[lastMetadataIdx_];
+		rpiMetadata.mergeCopy(lastMetadata);
 		processPending_ = false;
 		return;
 	}
@@ -1147,7 +1149,7 @@ void IPARPi::processStats(unsigned int bufferId)
 		ControlList ctrls(sensorCtrls_);
 		applyAGC(&agcStatus, ctrls);
 
-		setDelayedControls.emit(ctrls);
+		setDelayedControls.emit(ctrls, metadataIdx_);
 	}
 }
 
diff --git a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
index 23f2460190f4..8f6c6c0ce89f 100644
--- a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
+++ b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
@@ -206,7 +206,7 @@ public:
 	void runIsp(uint32_t bufferId);
 	void embeddedComplete(uint32_t bufferId);
 	void setIspControls(const ControlList &controls);
-	void setDelayedControls(const ControlList &controls);
+	void setDelayedControls(const ControlList &controls, uint32_t delayCookie);
 	void setSensorControls(ControlList &controls);
 	void unicamTimeout();
 
@@ -262,6 +262,7 @@ public:
 	struct BayerFrame {
 		FrameBuffer *buffer;
 		ControlList controls;
+		unsigned int delayCookie;
 	};
 
 	std::queue<BayerFrame> bayerQueue_;
@@ -294,6 +295,9 @@ public:
 	/* Have internal buffers been allocated? */
 	bool buffersAllocated_;
 
+	/* Frame cookie to pass to the IPA */
+	unsigned int ipaCookie_;
+
 private:
 	void checkRequestCompleted();
 	void fillRequestMetadata(const ControlList &bufferControls,
@@ -1064,7 +1068,8 @@ int PipelineHandlerRPi::start(Camera *camera, const ControlList *controls)
 	 * Reset the delayed controls with the gain and exposure values set by
 	 * the IPA.
 	 */
-	data->delayedCtrls_->reset();
+	data->ipaCookie_ = 0;
+	data->delayedCtrls_->reset(data->ipaCookie_);
 
 	data->state_ = RPiCameraData::State::Idle;
 
@@ -1792,9 +1797,9 @@ void RPiCameraData::setIspControls(const ControlList &controls)
 	handleState();
 }
 
-void RPiCameraData::setDelayedControls(const ControlList &controls)
+void RPiCameraData::setDelayedControls(const ControlList &controls, uint32_t delayCookie)
 {
-	if (!delayedCtrls_->push(controls))
+	if (!delayedCtrls_->push(controls, delayCookie))
 		LOG(RPI, Error) << "V4L2 DelayedControl set failed";
 	handleState();
 }
@@ -1867,13 +1872,13 @@ void RPiCameraData::unicamBufferDequeue(FrameBuffer *buffer)
 		 * Lookup the sensor controls used for this frame sequence from
 		 * DelayedControl and queue them along with the frame buffer.
 		 */
-		auto [ctrl, cookie] = delayedCtrls_->get(buffer->metadata().sequence);
+		auto [ctrl, delayCookie] = delayedCtrls_->get(buffer->metadata().sequence);
 		/*
 		 * Add the frame timestamp to the ControlList for the IPA to use
 		 * as it does not receive the FrameBuffer object.
 		 */
 		ctrl.set(controls::SensorTimestamp, buffer->metadata().timestamp);
-		bayerQueue_.push({ buffer, std::move(ctrl) });
+		bayerQueue_.push({ buffer, std::move(ctrl), delayCookie });
 	} else {
 		embeddedQueue_.push(buffer);
 	}
@@ -2168,6 +2173,8 @@ void RPiCameraData::tryRunPipeline()
 	ipa::RPi::ISPConfig ispPrepare;
 	ispPrepare.bayerBufferId = ipa::RPi::MaskBayerData | bayerId;
 	ispPrepare.controls = std::move(bayerFrame.controls);
+	ispPrepare.ipaCookie = ipaCookie_++;
+	ispPrepare.delayCookie = bayerFrame.delayCookie;
 
 	if (embeddedBuffer) {
 		unsigned int embeddedId = unicam_[Unicam::Embedded].getBufferId(embeddedBuffer);
-- 
2.25.1