libcamera: pipeline: rkisp1: Attach to an IPA

Add the plumbing to the pipeline handler to interact with an IPA module.
This change makes the usage of an IPA module mandatory for the rkisp1
pipeline.

The RkISP1 pipeline handler makes use of a timeline component to
schedule actions. This might be useful for other pipeline handlers going
forward so keep the generic timeline implementation separate to make it
easy to break out.

Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

4 files changed, 831 insertions, 17 deletions

diff --git a/src/libcamera/pipeline/rkisp1/meson.build b/src/libcamera/pipeline/rkisp1/meson.build
index f1cc4046..d04fb452 100644
--- a/src/libcamera/pipeline/rkisp1/meson.build
+++ b/src/libcamera/pipeline/rkisp1/meson.build
@@ -1,3 +1,4 @@
 libcamera_sources += files([
     'rkisp1.cpp',
+    'timeline.cpp',
 ])
diff --git a/src/libcamera/pipeline/rkisp1/rkisp1.cpp b/src/libcamera/pipeline/rkisp1/rkisp1.cpp
index de4ab523..029d5868 100644
--- a/src/libcamera/pipeline/rkisp1/rkisp1.cpp
+++ b/src/libcamera/pipeline/rkisp1/rkisp1.cpp
@@ -9,32 +9,115 @@
 #include <array>
 #include <iomanip>
 #include <memory>
-#include <vector>
+#include <queue>
 
 #include <linux/media-bus-format.h>
 
+#include <ipa/rkisp1.h>
+#include <libcamera/buffer.h>
 #include <libcamera/camera.h>
+#include <libcamera/control_ids.h>
 #include <libcamera/request.h>
 #include <libcamera/stream.h>
 
 #include "camera_sensor.h"
 #include "device_enumerator.h"
+#include "ipa_manager.h"
 #include "log.h"
 #include "media_device.h"
 #include "pipeline_handler.h"
+#include "timeline.h"
 #include "utils.h"
 #include "v4l2_subdevice.h"
 #include "v4l2_videodevice.h"
 
+#define RKISP1_PARAM_BASE 0x100
+#define RKISP1_STAT_BASE 0x200
+
 namespace libcamera {
 
 LOG_DEFINE_CATEGORY(RkISP1)
 
+class PipelineHandlerRkISP1;
+class RkISP1ActionQueueBuffers;
+
+enum RkISP1ActionType {
+	SetSensor,
+	SOE,
+	QueueBuffers,
+};
+
+struct RkISP1FrameInfo {
+	unsigned int frame;
+	Request *request;
+
+	Buffer *paramBuffer;
+	Buffer *statBuffer;
+	Buffer *videoBuffer;
+
+	bool paramFilled;
+	bool paramDequeued;
+	bool metadataProcessed;
+};
+
+class RkISP1Frames
+{
+public:
+	RkISP1Frames(PipelineHandler *pipe);
+
+	RkISP1FrameInfo *create(unsigned int frame, Request *request, Stream *stream);
+	int destroy(unsigned int frame);
+
+	RkISP1FrameInfo *find(unsigned int frame);
+	RkISP1FrameInfo *find(Buffer *buffer);
+	RkISP1FrameInfo *find(Request *request);
+
+private:
+	PipelineHandlerRkISP1 *pipe_;
+	std::map<unsigned int, RkISP1FrameInfo *> frameInfo_;
+};
+
+class RkISP1Timeline : public Timeline
+{
+public:
+	RkISP1Timeline()
+		: Timeline()
+	{
+		setDelay(SetSensor, -1, 5);
+		setDelay(SOE, 0, -1);
+		setDelay(QueueBuffers, -1, 10);
+	}
+
+	void bufferReady(Buffer *buffer)
+	{
+		/*
+		 * Calculate SOE by taking the end of DMA set by the kernel and applying
+		 * the time offsets provideprovided by the IPA to find the best estimate
+		 * of SOE.
+		 */
+
+		ASSERT(frameOffset(SOE) == 0);
+
+		utils::time_point soe = std::chrono::time_point<utils::clock>()
+			+ std::chrono::nanoseconds(buffer->timestamp())
+			+ timeOffset(SOE);
+
+		notifyStartOfExposure(buffer->sequence(), soe);
+	}
+
+	void setDelay(unsigned int type, int frame, int msdelay)
+	{
+		utils::duration delay = std::chrono::milliseconds(msdelay);
+		setRawDelay(type, frame, delay);
+	}
+};
+
 class RkISP1CameraData : public CameraData
 {
 public:
 	RkISP1CameraData(PipelineHandler *pipe)
-		: CameraData(pipe), sensor_(nullptr)
+		: CameraData(pipe), sensor_(nullptr), frame_(0),
+		  frameInfo_(pipe)
 	{
 	}
 
@@ -43,8 +126,20 @@ public:
 		delete sensor_;
 	}
 
+	int loadIPA();
+
 	Stream stream_;
 	CameraSensor *sensor_;
+	unsigned int frame_;
+	std::vector<IPABuffer> ipaBuffers_;
+	RkISP1Frames frameInfo_;
+	RkISP1Timeline timeline_;
+
+private:
+	void queueFrameAction(unsigned int frame,
+			      const IPAOperationData &action);
+
+	void metadataReady(unsigned int frame, const ControlList &metadata);
 };
 
 class RkISP1CameraConfiguration : public CameraConfiguration
@@ -99,18 +194,235 @@ private:
 			PipelineHandler::cameraData(camera));
 	}
 
+	friend RkISP1ActionQueueBuffers;
+	friend RkISP1CameraData;
+	friend RkISP1Frames;
+
 	int initLinks();
 	int createCamera(MediaEntity *sensor);
+	void tryCompleteRequest(Request *request);
 	void bufferReady(Buffer *buffer);
+	void paramReady(Buffer *buffer);
+	void statReady(Buffer *buffer);
 
 	MediaDevice *media_;
 	V4L2Subdevice *dphy_;
 	V4L2Subdevice *isp_;
 	V4L2VideoDevice *video_;
+	V4L2VideoDevice *param_;
+	V4L2VideoDevice *stat_;
+
+	BufferPool paramPool_;
+	BufferPool statPool_;
+
+	std::queue<Buffer *> paramBuffers_;
+	std::queue<Buffer *> statBuffers_;
 
 	Camera *activeCamera_;
 };
 
+RkISP1Frames::RkISP1Frames(PipelineHandler *pipe)
+	: pipe_(dynamic_cast<PipelineHandlerRkISP1 *>(pipe))
+{
+}
+
+RkISP1FrameInfo *RkISP1Frames::create(unsigned int frame, Request *request, Stream *stream)
+{
+	if (pipe_->paramBuffers_.empty()) {
+		LOG(RkISP1, Error) << "Parameters buffer underrun";
+		return nullptr;
+	}
+	Buffer *paramBuffer = pipe_->paramBuffers_.front();
+
+	if (pipe_->statBuffers_.empty()) {
+		LOG(RkISP1, Error) << "Statisitc buffer underrun";
+		return nullptr;
+	}
+	Buffer *statBuffer = pipe_->statBuffers_.front();
+
+	Buffer *videoBuffer = request->findBuffer(stream);
+	if (!videoBuffer) {
+		LOG(RkISP1, Error)
+			<< "Attempt to queue request with invalid stream";
+		return nullptr;
+	}
+
+	pipe_->paramBuffers_.pop();
+	pipe_->statBuffers_.pop();
+
+	RkISP1FrameInfo *info = new RkISP1FrameInfo;
+
+	info->frame = frame;
+	info->request = request;
+	info->paramBuffer = paramBuffer;
+	info->videoBuffer = videoBuffer;
+	info->statBuffer = statBuffer;
+	info->paramFilled = false;
+	info->paramDequeued = false;
+	info->metadataProcessed = false;
+
+	frameInfo_[frame] = info;
+
+	return info;
+}
+
+int RkISP1Frames::destroy(unsigned int frame)
+{
+	RkISP1FrameInfo *info = find(frame);
+	if (!info)
+		return -ENOENT;
+
+	pipe_->paramBuffers_.push(info->paramBuffer);
+	pipe_->statBuffers_.push(info->statBuffer);
+
+	frameInfo_.erase(info->frame);
+
+	delete info;
+
+	return 0;
+}
+
+RkISP1FrameInfo *RkISP1Frames::find(unsigned int frame)
+{
+	auto itInfo = frameInfo_.find(frame);
+
+	if (itInfo != frameInfo_.end())
+		return itInfo->second;
+
+	LOG(RkISP1, Error) << "Can't locate info from frame";
+	return nullptr;
+}
+
+RkISP1FrameInfo *RkISP1Frames::find(Buffer *buffer)
+{
+	for (auto &itInfo : frameInfo_) {
+		RkISP1FrameInfo *info = itInfo.second;
+
+		if (info->paramBuffer == buffer ||
+		    info->statBuffer == buffer ||
+		    info->videoBuffer == buffer)
+			return info;
+	}
+
+	LOG(RkISP1, Error) << "Can't locate info from buffer";
+	return nullptr;
+}
+
+RkISP1FrameInfo *RkISP1Frames::find(Request *request)
+{
+	for (auto &itInfo : frameInfo_) {
+		RkISP1FrameInfo *info = itInfo.second;
+
+		if (info->request == request)
+			return info;
+	}
+
+	LOG(RkISP1, Error) << "Can't locate info from request";
+	return nullptr;
+}
+
+class RkISP1ActionSetSensor : public FrameAction
+{
+public:
+	RkISP1ActionSetSensor(unsigned int frame, CameraSensor *sensor, V4L2ControlList controls)
+		: FrameAction(frame, SetSensor), sensor_(sensor), controls_(controls) {}
+
+protected:
+	void run() override
+	{
+		sensor_->setControls(&controls_);
+	}
+
+private:
+	CameraSensor *sensor_;
+	V4L2ControlList controls_;
+};
+
+class RkISP1ActionQueueBuffers : public FrameAction
+{
+public:
+	RkISP1ActionQueueBuffers(unsigned int frame, RkISP1CameraData *data,
+				 PipelineHandlerRkISP1 *pipe)
+		: FrameAction(frame, QueueBuffers), data_(data), pipe_(pipe)
+	{
+	}
+
+protected:
+	void run() override
+	{
+		RkISP1FrameInfo *info = data_->frameInfo_.find(frame());
+		if (!info)
+			LOG(RkISP1, Fatal) << "Frame not known";
+
+		if (info->paramFilled)
+			pipe_->param_->queueBuffer(info->paramBuffer);
+		else
+			LOG(RkISP1, Error)
+				<< "Parameters not ready on time for frame "
+				<< frame() << ", ignore parameters.";
+
+		pipe_->stat_->queueBuffer(info->statBuffer);
+		pipe_->video_->queueBuffer(info->videoBuffer);
+	}
+
+private:
+	RkISP1CameraData *data_;
+	PipelineHandlerRkISP1 *pipe_;
+};
+
+int RkISP1CameraData::loadIPA()
+{
+	ipa_ = IPAManager::instance()->createIPA(pipe_, 1, 1);
+	if (!ipa_)
+		return -ENOENT;
+
+	ipa_->queueFrameAction.connect(this,
+				       &RkISP1CameraData::queueFrameAction);
+
+	return 0;
+}
+
+void RkISP1CameraData::queueFrameAction(unsigned int frame,
+					const IPAOperationData &action)
+{
+	switch (action.operation) {
+	case RKISP1_IPA_ACTION_V4L2_SET: {
+		V4L2ControlList controls = action.v4l2controls[0];
+		timeline_.scheduleAction(utils::make_unique<RkISP1ActionSetSensor>(frame,
+										   sensor_,
+										   controls));
+		break;
+	}
+	case RKISP1_IPA_ACTION_PARAM_FILLED: {
+		RkISP1FrameInfo *info = frameInfo_.find(frame);
+		if (info)
+			info->paramFilled = true;
+		break;
+	}
+	case RKISP1_IPA_ACTION_METADATA:
+		metadataReady(frame, action.controls[0]);
+		break;
+	default:
+		LOG(RkISP1, Error) << "Unkown action " << action.operation;
+		break;
+	}
+}
+
+void RkISP1CameraData::metadataReady(unsigned int frame, const ControlList &metadata)
+{
+	PipelineHandlerRkISP1 *pipe =
+		static_cast<PipelineHandlerRkISP1 *>(pipe_);
+
+	RkISP1FrameInfo *info = frameInfo_.find(frame);
+	if (!info)
+		return;
+
+	info->request->metadata() = metadata;
+	info->metadataProcessed = true;
+
+	pipe->tryCompleteRequest(info->request);
+}
+
 RkISP1CameraConfiguration::RkISP1CameraConfiguration(Camera *camera,
 						     RkISP1CameraData *data)
 	: CameraConfiguration()
@@ -202,12 +514,14 @@ CameraConfiguration::Status RkISP1CameraConfiguration::validate()
 
 PipelineHandlerRkISP1::PipelineHandlerRkISP1(CameraManager *manager)
 	: PipelineHandler(manager), dphy_(nullptr), isp_(nullptr),
-	  video_(nullptr)
+	  video_(nullptr), param_(nullptr), stat_(nullptr)
 {
 }
 
 PipelineHandlerRkISP1::~PipelineHandlerRkISP1()
 {
+	delete param_;
+	delete stat_;
 	delete video_;
 	delete isp_;
 	delete dphy_;
@@ -324,6 +638,18 @@ int PipelineHandlerRkISP1::configure(Camera *camera, CameraConfiguration *c)
 		return -EINVAL;
 	}
 
+	V4L2DeviceFormat paramFormat = {};
+	paramFormat.fourcc = V4L2_META_FMT_RK_ISP1_PARAMS;
+	ret = param_->setFormat(&paramFormat);
+	if (ret)
+		return ret;
+
+	V4L2DeviceFormat statFormat = {};
+	statFormat.fourcc = V4L2_META_FMT_RK_ISP1_STAT_3A;
+	ret = stat_->setFormat(&statFormat);
+	if (ret)
+		return ret;
+
 	cfg.setStream(&data->stream_);
 
 	return 0;
@@ -332,39 +658,135 @@ int PipelineHandlerRkISP1::configure(Camera *camera, CameraConfiguration *c)
 int PipelineHandlerRkISP1::allocateBuffers(Camera *camera,
 					   const std::set<Stream *> &streams)
 {
+	RkISP1CameraData *data = cameraData(camera);
 	Stream *stream = *streams.begin();
+	int ret;
 
 	if (stream->memoryType() == InternalMemory)
-		return video_->exportBuffers(&stream->bufferPool());
+		ret = video_->exportBuffers(&stream->bufferPool());
 	else
-		return video_->importBuffers(&stream->bufferPool());
+		ret = video_->importBuffers(&stream->bufferPool());
+
+	if (ret)
+		return ret;
+
+	paramPool_.createBuffers(stream->configuration().bufferCount + 1);
+	ret = param_->exportBuffers(&paramPool_);
+	if (ret) {
+		video_->releaseBuffers();
+		return ret;
+	}
+
+	statPool_.createBuffers(stream->configuration().bufferCount + 1);
+	ret = stat_->exportBuffers(&statPool_);
+	if (ret) {
+		param_->releaseBuffers();
+		video_->releaseBuffers();
+		return ret;
+	}
+
+	for (unsigned int i = 0; i < stream->configuration().bufferCount + 1; i++) {
+		data->ipaBuffers_.push_back({ .id = RKISP1_PARAM_BASE | i,
+					      .memory = paramPool_.buffers()[i] });
+		paramBuffers_.push(new Buffer(i));
+	}
+
+	for (unsigned int i = 0; i < stream->configuration().bufferCount + 1; i++) {
+		data->ipaBuffers_.push_back({ .id = RKISP1_STAT_BASE | i,
+					      .memory = statPool_.buffers()[i] });
+		statBuffers_.push(new Buffer(i));
+	}
+
+	data->ipa_->mapBuffers(data->ipaBuffers_);
+
+	return ret;
 }
 
 int PipelineHandlerRkISP1::freeBuffers(Camera *camera,
 				       const std::set<Stream *> &streams)
 {
+	RkISP1CameraData *data = cameraData(camera);
+
+	while (!statBuffers_.empty()) {
+		delete statBuffers_.front();
+		statBuffers_.pop();
+	}
+
+	while (!paramBuffers_.empty()) {
+		delete paramBuffers_.front();
+		paramBuffers_.pop();
+	}
+
+	std::vector<unsigned int> ids;
+	for (IPABuffer &ipabuf : data->ipaBuffers_)
+		ids.push_back(ipabuf.id);
+
+	data->ipa_->unmapBuffers(ids);
+	data->ipaBuffers_.clear();
+
+	if (param_->releaseBuffers())
+		LOG(RkISP1, Error) << "Failed to release parameters buffers";
+
+	if (stat_->releaseBuffers())
+		LOG(RkISP1, Error) << "Failed to release stat buffers";
+
 	if (video_->releaseBuffers())
-		LOG(RkISP1, Error) << "Failed to release buffers";
+		LOG(RkISP1, Error) << "Failed to release video buffers";
 
 	return 0;
 }
 
 int PipelineHandlerRkISP1::start(Camera *camera)
 {
+	RkISP1CameraData *data = cameraData(camera);
 	int ret;
 
+	data->frame_ = 0;
+
+	ret = param_->streamOn();
+	if (ret) {
+		LOG(RkISP1, Error)
+			<< "Failed to start parameters " << camera->name();
+		return ret;
+	}
+
+	ret = stat_->streamOn();
+	if (ret) {
+		param_->streamOff();
+		LOG(RkISP1, Error)
+			<< "Failed to start statistics " << camera->name();
+		return ret;
+	}
+
 	ret = video_->streamOn();
-	if (ret)
+	if (ret) {
+		param_->streamOff();
+		stat_->streamOff();
+
 		LOG(RkISP1, Error)
 			<< "Failed to start camera " << camera->name();
+	}
 
 	activeCamera_ = camera;
 
+	/* Inform IPA of stream configuration and sensor controls. */
+	std::map<unsigned int, IPAStream> streamConfig;
+	streamConfig[0] = {
+		.pixelFormat = data->stream_.configuration().pixelFormat,
+		.size = data->stream_.configuration().size,
+	};
+
+	std::map<unsigned int, V4L2ControlInfoMap> entityControls;
+	entityControls[0] = data->sensor_->controls();
+
+	data->ipa_->configure(streamConfig, entityControls);
+
 	return ret;
 }
 
 void PipelineHandlerRkISP1::stop(Camera *camera)
 {
+	RkISP1CameraData *data = cameraData(camera);
 	int ret;
 
 	ret = video_->streamOff();
@@ -372,6 +794,18 @@ void PipelineHandlerRkISP1::stop(Camera *camera)
 		LOG(RkISP1, Warning)
 			<< "Failed to stop camera " << camera->name();
 
+	ret = stat_->streamOff();
+	if (ret)
+		LOG(RkISP1, Warning)
+			<< "Failed to stop statistics " << camera->name();
+
+	ret = param_->streamOff();
+	if (ret)
+		LOG(RkISP1, Warning)
+			<< "Failed to stop parameters " << camera->name();
+
+	data->timeline_.reset();
+
 	activeCamera_ = nullptr;
 }
 
@@ -380,18 +814,24 @@ int PipelineHandlerRkISP1::queueRequest(Camera *camera, Request *request)
 	RkISP1CameraData *data = cameraData(camera);
 	Stream *stream = &data->stream_;
 
-	Buffer *buffer = request->findBuffer(stream);
-	if (!buffer) {
-		LOG(RkISP1, Error)
-			<< "Attempt to queue request with invalid stream";
+	PipelineHandler::queueRequest(camera, request);
+
+	RkISP1FrameInfo *info = data->frameInfo_.create(data->frame_, request,
+							stream);
+	if (!info)
 		return -ENOENT;
-	}
 
-	int ret = video_->queueBuffer(buffer);
-	if (ret < 0)
-		return ret;
+	IPAOperationData op;
+	op.operation = RKISP1_IPA_EVENT_QUEUE_REQUEST;
+	op.data = { data->frame_, RKISP1_PARAM_BASE | info->paramBuffer->index() };
+	op.controls = { request->controls() };
+	data->ipa_->processEvent(op);
 
-	PipelineHandler::queueRequest(camera, request);
+	data->timeline_.scheduleAction(utils::make_unique<RkISP1ActionQueueBuffers>(data->frame_,
+										    data,
+										    this));
+
+	data->frame_++;
 
 	return 0;
 }
@@ -435,11 +875,19 @@ int PipelineHandlerRkISP1::createCamera(MediaEntity *sensor)
 	std::unique_ptr<RkISP1CameraData> data =
 		utils::make_unique<RkISP1CameraData>(this);
 
+	data->controlInfo_.emplace(std::piecewise_construct,
+				   std::forward_as_tuple(&controls::AeEnable),
+				   std::forward_as_tuple(false, true));
+
 	data->sensor_ = new CameraSensor(sensor);
 	ret = data->sensor_->init();
 	if (ret)
 		return ret;
 
+	ret = data->loadIPA();
+	if (ret)
+		return ret;
+
 	std::set<Stream *> streams{ &data->stream_ };
 	std::shared_ptr<Camera> camera =
 		Camera::create(this, sensor->name(), streams);
@@ -478,7 +926,17 @@ bool PipelineHandlerRkISP1::match(DeviceEnumerator *enumerator)
 	if (video_->open() < 0)
 		return false;
 
+	stat_ = V4L2VideoDevice::fromEntityName(media_, "rkisp1-statistics");
+	if (stat_->open() < 0)
+		return false;
+
+	param_ = V4L2VideoDevice::fromEntityName(media_, "rkisp1-input-params");
+	if (param_->open() < 0)
+		return false;
+
 	video_->bufferReady.connect(this, &PipelineHandlerRkISP1::bufferReady);
+	stat_->bufferReady.connect(this, &PipelineHandlerRkISP1::statReady);
+	param_->bufferReady.connect(this, &PipelineHandlerRkISP1::paramReady);
 
 	/* Configure default links. */
 	if (initLinks() < 0) {
@@ -504,13 +962,69 @@ bool PipelineHandlerRkISP1::match(DeviceEnumerator *enumerator)
  * Buffer Handling
  */
 
+void PipelineHandlerRkISP1::tryCompleteRequest(Request *request)
+{
+	RkISP1CameraData *data = cameraData(activeCamera_);
+	RkISP1FrameInfo *info = data->frameInfo_.find(request);
+	if (!info)
+		return;
+
+	if (request->hasPendingBuffers())
+		return;
+
+	if (!info->metadataProcessed)
+		return;
+
+	if (!info->paramDequeued)
+		return;
+
+	completeRequest(activeCamera_, request);
+
+	data->frameInfo_.destroy(info->frame);
+}
+
 void PipelineHandlerRkISP1::bufferReady(Buffer *buffer)
 {
 	ASSERT(activeCamera_);
+	RkISP1CameraData *data = cameraData(activeCamera_);
 	Request *request = buffer->request();
 
+	data->timeline_.bufferReady(buffer);
+
+	if (data->frame_ <= buffer->sequence())
+		data->frame_ = buffer->sequence() + 1;
+
 	completeBuffer(activeCamera_, request, buffer);
-	completeRequest(activeCamera_, request);
+	tryCompleteRequest(request);
+}
+
+void PipelineHandlerRkISP1::paramReady(Buffer *buffer)
+{
+	ASSERT(activeCamera_);
+	RkISP1CameraData *data = cameraData(activeCamera_);
+
+	RkISP1FrameInfo *info = data->frameInfo_.find(buffer);
+
+	info->paramDequeued = true;
+	tryCompleteRequest(info->request);
+}
+
+void PipelineHandlerRkISP1::statReady(Buffer *buffer)
+{
+	ASSERT(activeCamera_);
+	RkISP1CameraData *data = cameraData(activeCamera_);
+
+	RkISP1FrameInfo *info = data->frameInfo_.find(buffer);
+	if (!info)
+		return;
+
+	unsigned int frame = info->frame;
+	unsigned int statid = RKISP1_STAT_BASE | info->statBuffer->index();
+
+	IPAOperationData op;
+	op.operation = RKISP1_IPA_EVENT_SIGNAL_STAT_BUFFER;
+	op.data = { frame, statid };
+	data->ipa_->processEvent(op);
 }
 
 REGISTER_PIPELINE_HANDLER(PipelineHandlerRkISP1);
diff --git a/src/libcamera/pipeline/rkisp1/timeline.cpp b/src/libcamera/pipeline/rkisp1/timeline.cpp
new file mode 100644
index 00000000..b98a1668
--- /dev/null
+++ b/src/libcamera/pipeline/rkisp1/timeline.cpp
@@ -0,0 +1,227 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * timeline.cpp - Timeline for per-frame control
+ */
+
+#include "timeline.h"
+
+#include "log.h"
+
+/**
+ * \file timeline.h
+ * \brief Timeline for per-frame control
+ */
+
+namespace libcamera {
+
+LOG_DEFINE_CATEGORY(Timeline)
+
+/**
+ * \class FrameAction
+ * \brief Action that can be schedule on a Timeline
+ *
+ * A frame action is an event schedule to be executed on a Timeline. A frame
+ * action has two primal attributes a frame number and a type.
+ *
+ * The frame number describes the frame to which the action is associated. The
+ * type is a numerical ID which identifies the action within the pipeline and
+ * IPA protocol.
+ */
+
+/**
+ * \class Timeline
+ * \brief Executor of FrameAction
+ *
+ * The timeline has three primary functions:
+ *
+ * 1. Keep track of the Start of Exposure (SOE) for every frame processed by
+ *    the hardware. Using this information it shall keep an up-to-date estimate
+ *    of the frame interval (time between two consecutive SOE events).
+ *
+ *    The estimated frame interval together with recorded SOE events are the
+ *    foundation for how the timeline schedule FrameAction at specific points
+ *    in time.
+ *    \todo Improve the frame interval estimation algorithm.
+ *
+ * 2. Keep track of current delays for different types of actions. The delays
+ *    for different actions might differ during a capture session. Exposure time
+ *    effects the over all FPS and different ISP parameters might impacts its
+ *    processing time.
+ *
+ *    The action type delays shall be updated by the IPA in conjunction with
+ *    how it changes the capture parameters.
+ *
+ * 3. Schedule actions on the timeline. This is the process of taking a
+ *    FrameAction which contains an abstract description of what frame and
+ *    what type of action it contains and turning that into an time point
+ *    and make sure the action is executed at that time.
+ */
+
+Timeline::Timeline()
+	: frameInterval_(0)
+{
+	timer_.timeout.connect(this, &Timeline::timeout);
+}
+
+/**
+ * \brief Reset and stop the timeline
+ *
+ * The timeline needs to be reset when the timeline should no longer execute
+ * actions. A timeline should be reset between two capture sessions to prevent
+ * the old capture session to effect the second one.
+ */
+void Timeline::reset()
+{
+	timer_.stop();
+
+	actions_.clear();
+	history_.clear();
+}
+
+/**
+ * \brief Schedule an action on the timeline
+ * \param[in] action FrameAction to schedule
+ *
+ * The act of scheduling an action to the timeline is the process of taking
+ * the properties of the action (type, frame and time offsets) and translating
+ * that to a time point using the current values for the action type timings
+ * value recorded in the timeline. If an action is scheduled too late, execute
+ * it immediately.
+ */
+void Timeline::scheduleAction(std::unique_ptr<FrameAction> action)
+{
+	unsigned int lastFrame;
+	utils::time_point lastTime;
+
+	if (history_.empty()) {
+		lastFrame = 0;
+		lastTime = std::chrono::steady_clock::now();
+	} else {
+		lastFrame = history_.back().first;
+		lastTime = history_.back().second;
+	}
+
+	/*
+	 * Calculate when the action shall be schedule by first finding out how
+	 * many frames in the future the action acts on and then add the actions
+	 * frame offset. After the spatial frame offset is found out translate
+	 * that to a time point by using the last estimated start of exposure
+	 * (SOE) as the fixed offset. Lastly add the action time offset to the
+	 * time point.
+	 */
+	int frame = action->frame() - lastFrame + frameOffset(action->type());
+	utils::time_point deadline = lastTime + frame * frameInterval_
+		+ timeOffset(action->type());
+
+	utils::time_point now = std::chrono::steady_clock::now();
+	if (deadline < now) {
+		LOG(Timeline, Warning)
+			<< "Action scheduled too late "
+			<< utils::time_point_to_string(deadline)
+			<< ", run now " << utils::time_point_to_string(now);
+		action->run();
+	} else {
+		actions_.insert({ deadline, std::move(action) });
+		updateDeadline();
+	}
+}
+
+void Timeline::notifyStartOfExposure(unsigned int frame, utils::time_point time)
+{
+	history_.push_back(std::make_pair(frame, time));
+
+	if (history_.size() <= HISTORY_DEPTH / 2)
+		return;
+
+	while (history_.size() > HISTORY_DEPTH)
+		history_.pop_front();
+
+	/* Update esitmated time between two start of exposures. */
+	utils::duration sumExposures(0);
+	unsigned int numExposures = 0;
+
+	utils::time_point lastTime;
+	for (auto it = history_.begin(); it != history_.end(); it++) {
+		if (it != history_.begin()) {
+			sumExposures += it->second - lastTime;
+			numExposures++;
+		}
+
+		lastTime = it->second;
+	}
+
+	frameInterval_ = sumExposures;
+	if (numExposures)
+		frameInterval_ /= numExposures;
+}
+
+int Timeline::frameOffset(unsigned int type) const
+{
+	const auto it = delays_.find(type);
+	if (it == delays_.end()) {
+		LOG(Timeline, Error)
+			<< "No frame offset set for action type " << type;
+		return 0;
+	}
+
+	return it->second.first;
+}
+
+utils::duration Timeline::timeOffset(unsigned int type) const
+{
+	const auto it = delays_.find(type);
+	if (it == delays_.end()) {
+		LOG(Timeline, Error)
+			<< "No time offset set for action type " << type;
+		return utils::duration::zero();
+	}
+
+	return it->second.second;
+}
+
+void Timeline::setRawDelay(unsigned int type, int frame, utils::duration time)
+{
+	delays_[type] = std::make_pair(frame, time);
+}
+
+void Timeline::updateDeadline()
+{
+	if (actions_.empty())
+		return;
+
+	const utils::time_point &deadline = actions_.begin()->first;
+
+	if (timer_.isRunning() && deadline >= timer_.deadline())
+		return;
+
+	if (deadline <= std::chrono::steady_clock::now()) {
+		timeout(&timer_);
+		return;
+	}
+
+	timer_.start(deadline);
+}
+
+void Timeline::timeout(Timer *timer)
+{
+	utils::time_point now = std::chrono::steady_clock::now();
+
+	for (auto it = actions_.begin(); it != actions_.end();) {
+		const utils::time_point &sched = it->first;
+
+		if (sched > now)
+			break;
+
+		FrameAction *action = it->second.get();
+
+		action->run();
+
+		it = actions_.erase(it);
+	}
+
+	updateDeadline();
+}
+
+} /* namespace libcamera */
diff --git a/src/libcamera/pipeline/rkisp1/timeline.h b/src/libcamera/pipeline/rkisp1/timeline.h
new file mode 100644
index 00000000..9d30e4ea
--- /dev/null
+++ b/src/libcamera/pipeline/rkisp1/timeline.h
@@ -0,0 +1,72 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * timeline.h - Timeline for per-frame controls
+ */
+#ifndef __LIBCAMERA_TIMELINE_H__
+#define __LIBCAMERA_TIMELINE_H__
+
+#include <list>
+#include <map>
+
+#include <libcamera/timer.h>
+
+#include "utils.h"
+
+namespace libcamera {
+
+class FrameAction
+{
+public:
+	FrameAction(unsigned int frame, unsigned int type)
+		: frame_(frame), type_(type) {}
+
+	virtual ~FrameAction() {}
+
+	unsigned int frame() const { return frame_; }
+	unsigned int type() const { return type_; }
+
+	virtual void run() = 0;
+
+private:
+	unsigned int frame_;
+	unsigned int type_;
+};
+
+class Timeline
+{
+public:
+	Timeline();
+	virtual ~Timeline() {}
+
+	virtual void reset();
+	virtual void scheduleAction(std::unique_ptr<FrameAction> action);
+	virtual void notifyStartOfExposure(unsigned int frame, utils::time_point time);
+
+	utils::duration frameInterval() const { return frameInterval_; }
+
+protected:
+	int frameOffset(unsigned int type) const;
+	utils::duration timeOffset(unsigned int type) const;
+
+	void setRawDelay(unsigned int type, int frame, utils::duration time);
+
+	std::map<unsigned int, std::pair<int, utils::duration>> delays_;
+
+private:
+	static constexpr unsigned int HISTORY_DEPTH = 10;
+
+	void timeout(Timer *timer);
+	void updateDeadline();
+
+	std::list<std::pair<unsigned int, utils::time_point>> history_;
+	std::multimap<utils::time_point, std::unique_ptr<FrameAction>> actions_;
+	utils::duration frameInterval_;
+
+	Timer timer_;
+};
+
+} /* namespace libcamera */
+
+#endif /* __LIBCAMERA_TIMELINE_H__ */