[libcamera-devel] [PATCH v2 4/4] ipa: vimc: Send and retrieve FrameBuffers from IPA

[Umang Jain]

Plumb through VIMC mojo interface to enable buffers passing.
Since VIMC is a virtual test driver and does not have actual
IPA buffers (parameters and statistics), we can only pass them
as is, to and from the IPA. The buffers used here are mock
FrameBuffers which are dmabuf backed(in other words, mmap()able
through MappedFramebuffer inside the IPA).

This commits shows:
- Passing and filling the parameter buffer from the pipeline handler to
  the IPA.
- Passing request controls ControlList to the IPA.

Any tests using VIMC will now loop in the IPA paths. Any tests running
in isolated mode will help us to test IPA IPC code paths especially
around (de)serialization of data passing from pipeline handlers to the
IPA. Future IPA interface tests can simply extend the VIMC mojom
interface to achieve/test a specific use case as required.

Signed-off-by: Umang Jain <umang.jain at ideasonboard.com>
---
 include/libcamera/ipa/vimc.mojom     | 14 +++++++++++++-
 src/ipa/vimc/vimc.cpp                | 19 +++++++++++++++++++
 src/libcamera/pipeline/vimc/vimc.cpp | 11 +++++++++++
 3 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/include/libcamera/ipa/vimc.mojom b/include/libcamera/ipa/vimc.mojom
index 8cb240d3..85a2d8e4 100644
--- a/include/libcamera/ipa/vimc.mojom
+++ b/include/libcamera/ipa/vimc.mojom
@@ -29,8 +29,20 @@ interface IPAVimcInterface {
 
 	mapBuffers(array<libcamera.IPABuffer> buffers);
 	unmapBuffers(array<uint32> ids);
+
+	/*
+	 * VIMC being a virtual test driver does not have actual parameters
+	 * and statistics buffers. However, VIMC pipeline creates mock IPA
+	 * buffers and map it to IPA.
+	 *
+	 * Since, we are not working with actual IPA buffers here,
+	 * following are mostly stub functions, introduced to leverage IPA
+	 * IPC tests.
+	 */
+	[async] fillParams(uint32 frame, uint32 bufferId);
+	[async] processControls(uint32 frame, libcamera.ControlList controls);
 };
 
 interface IPAVimcEventInterface {
-	dummyEvent(uint32 val);
+	paramsFilled(uint32 bufferId);
 };
diff --git a/src/ipa/vimc/vimc.cpp b/src/ipa/vimc/vimc.cpp
index 082b2db7..be189181 100644
--- a/src/ipa/vimc/vimc.cpp
+++ b/src/ipa/vimc/vimc.cpp
@@ -43,6 +43,9 @@ public:
 	void mapBuffers(const std::vector<IPABuffer> &buffers) override;
 	void unmapBuffers(const std::vector<unsigned int> &ids) override;
 
+	void fillParams(uint32_t frame, uint32_t bufferId) override;
+	void processControls(uint32_t frame, const ControlList &controls) override;
+
 private:
 	void initTrace();
 	void trace(enum ipa::vimc::IPAOperationCode operation);
@@ -125,6 +128,22 @@ void IPAVimc::unmapBuffers(const std::vector<unsigned int> &ids)
 	}
 }
 
+void IPAVimc::fillParams([[maybe_unused]] uint32_t frame, uint32_t bufferId)
+{
+	auto it = buffers_.find(bufferId);
+	if (it == buffers_.end()) {
+		LOG(IPAVimc, Error) << "Could not find parameter buffer";
+		return;
+	}
+
+	paramsFilled.emit(bufferId);
+}
+
+void IPAVimc::processControls([[maybe_unused]] uint32_t frame,
+			      [[maybe_unused]] const ControlList &controls)
+{
+}
+
 void IPAVimc::initTrace()
 {
 	struct stat fifoStat;
diff --git a/src/libcamera/pipeline/vimc/vimc.cpp b/src/libcamera/pipeline/vimc/vimc.cpp
index c44a6242..bfd545c8 100644
--- a/src/libcamera/pipeline/vimc/vimc.cpp
+++ b/src/libcamera/pipeline/vimc/vimc.cpp
@@ -52,6 +52,7 @@ public:
 	int init();
 	int allocateMockIPABuffers();
 	void bufferReady(FrameBuffer *buffer);
+	void paramsFilled(unsigned int id);
 
 	MediaDevice *media_;
 	std::unique_ptr<CameraSensor> sensor_;
@@ -433,6 +434,8 @@ int PipelineHandlerVimc::queueRequestDevice(Camera *camera, Request *request)
 	if (ret < 0)
 		return ret;
 
+	data->ipa_->processControls(request->sequence(), request->controls());
+
 	return 0;
 }
 
@@ -466,6 +469,8 @@ bool PipelineHandlerVimc::match(DeviceEnumerator *enumerator)
 		return false;
 	}
 
+	data->ipa_->paramsFilled.connect(data.get(), &VimcCameraData::paramsFilled);
+
 	std::string conf = data->ipa_->configurationFile("vimc.conf");
 	data->ipa_->init(IPASettings{ conf, data->sensor_->model() });
 
@@ -570,6 +575,8 @@ void VimcCameraData::bufferReady(FrameBuffer *buffer)
 
 	pipe_->completeBuffer(request, buffer);
 	pipe_->completeRequest(request);
+
+	ipa_->fillParams(request->sequence(), mockIPABufs_[0]->cookie());
 }
 
 int VimcCameraData::allocateMockIPABuffers()
@@ -591,6 +598,10 @@ int VimcCameraData::allocateMockIPABuffers()
 	return video_->exportBuffers(bufCount, &mockIPABufs_);
 }
 
+void VimcCameraData::paramsFilled([[maybe_unused]] unsigned int id)
+{
+}
+
 REGISTER_PIPELINE_HANDLER(PipelineHandlerVimc)
 
 } /* namespace libcamera */
-- 
2.31.0