From 5c35fa04d01f6b8505a0ba37a0d8c3e259004576 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Niklas=20S=C3=B6derlund?= Date: Tue, 8 Oct 2019 02:45:31 +0200 Subject: libcamera: ipa: Extend to support IPA interactions MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The IPA interface needs to support interactions with the pipeline; add interfaces to control the sensor and handling of request ISP parameters and statistics. Signed-off-by: Niklas Söderlund Reviewed-by: Jacopo Mondi Reviewed-by: Laurent Pinchart --- src/libcamera/ipa_interface.cpp | 219 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 219 insertions(+) (limited to 'src/libcamera/ipa_interface.cpp') diff --git a/src/libcamera/ipa_interface.cpp b/src/libcamera/ipa_interface.cpp index d7d8ca88..4fb17829 100644 --- a/src/libcamera/ipa_interface.cpp +++ b/src/libcamera/ipa_interface.cpp @@ -10,13 +10,146 @@ /** * \file ipa_interface.h * \brief Image Processing Algorithm interface + * + * Pipeline handlers communicate with IPAs through a C++ interface defined by + * the IPAInterface class. The class defines high-level methods and signals to + * configure the IPA, notify it of events, and receive actions back from the + * IPA. + * + * Pipeline handlers define the set of events and actions used to communicate + * with their IPA. These are collectively referred to as IPA operations and + * define the pipeline handler-specific IPA protocol. Each operation defines the + * data that it carries, and how the data is encoded in the IPAOperationData + * structure. + * + * IPAs can be isolated in a separate process. This implies that all arguments + * to the IPA interface may need to be transferred over IPC. The IPA interface + * thus uses serialisable data types only. The IPA interface defines custom data + * structures that mirror core libcamera structures when the latter are not + * suitable, such as IPAStream to carry StreamConfiguration data. + * + * Due to IPC, synchronous communication between pipeline handlers and IPAs can + * be costly. For that reason, the interface operates asynchronously. This + * implies that methods don't return a status, and that both methods and signals + * may copy their arguments. */ namespace libcamera { +/** + * \struct IPAStream + * \brief Stream configuration for the IPA interface + * + * The IPAStream structure stores stream configuration parameters needed by the + * IPAInterface::configure() method. It mirrors the StreamConfiguration class + * that is not suitable for this purpose due to not being serialisable. + */ + +/** + * \var IPAStream::pixelFormat + * \brief The stream pixel format + */ + +/** + * \var IPAStream::size + * \brief The stream size in pixels + */ + +/** + * \struct IPABuffer + * \brief Buffer information for the IPA interface + * + * The IPABuffer structure associates buffer memory with a unique ID. It is + * used to map buffers to the IPA with IPAInterface::mapBuffers(), after which + * buffers will be identified by their ID in the IPA interface. + */ + +/** + * \var IPABuffer::id + * \brief The buffer unique ID + * + * Buffers mapped to the IPA are identified by numerical unique IDs. The IDs + * are chosen by the pipeline handler to fulfil the following constraints: + * + * - IDs shall be positive integers different than zero + * - IDs shall be unique among all mapped buffers + * + * When buffers are unmapped with IPAInterface::unmapBuffers() their IDs are + * freed and may be reused for new buffer mappings. + */ + +/** + * \var IPABuffer::memory + * \brief The buffer memory description + * + * The memory field stores the dmabuf handle and size for each plane of the + * buffer. + */ + +/** + * \struct IPAOperationData + * \brief Parameters for IPA operations + * + * The IPAOperationData structure carries parameters for the IPA operations + * performed through the IPAInterface::processEvent() method and the + * IPAInterface::queueFrameAction signal. + */ + +/** + * \var IPAOperationData::operation + * \brief IPA protocol operation + * + * The operation field describes which operation the receiver shall perform. It + * defines, through the IPA protocol, how the other fields of the structure are + * interpreted. The protocol freely assigns numerical values to operations. + */ + +/** + * \var IPAOperationData::data + * \brief Operation integer data + * + * The interpretation and position of different values in the array are defined + * by the IPA protocol. + */ + +/** + * \var IPAOperationData::controls + * \brief Operation controls data + * + * The interpretation and position of different values in the array are defined + * by the IPA protocol. + */ + +/** + * \var IPAOperationData::v4l2controls + * \brief Operation V4L2 controls data + * + * The interpretation and position of different values in the array are defined + * by the IPA protocol. + */ + /** * \class IPAInterface * \brief Interface for IPA implementation + * + * Every pipeline handler in libcamera may attach all or some of its cameras to + * an Image Processing Algorithm (IPA) module. An IPA module is developed for a + * specific pipeline handler and each pipeline handler may have multiple + * compatible IPA implementations, both open and closed source. + * + * To allow for multiple IPA modules for the same pipeline handler, a standard + * interface for the pipeline handler and IPA communication is needed. + * IPAInterface is this interface. + * + * The interface defines base data types and methods to exchange data. On top of + * this, each pipeline handler is responsible for defining specific operations + * that make up its IPA protocol, shared by all IPA modules compatible with the + * pipeline handler. + * + * The pipeline handler shall use the IPAManager to locate a compatible + * IPAInterface. The interface may then be used to interact with the IPA module. + * + * \todo Add reference to how pipelines shall document their protocol. */ /** @@ -24,4 +157,90 @@ namespace libcamera { * \brief Initialise the IPAInterface */ +/** + * \fn IPAInterface::configure() + * \brief Configure the IPA stream and sensor settings + * \param[in] streamConfig Configuration of all active streams + * \param[in] entityControls Controls provided by the pipeline entities + * + * This method shall be called when the camera is started to inform the IPA of + * the camera's streams and the sensor settings. The meaning of the numerical + * keys in the \a streamConfig and \a entityControls maps is defined by the IPA + * protocol. + */ + +/** + * \fn IPAInterface::mapBuffers() + * \brief Map buffers shared between the pipeline handler and the IPA + * \param[in] buffers List of buffers to map + * + * This method informs the IPA module of memory buffers set up by the pipeline + * handler that the IPA needs to access. It provides dmabuf file handles for + * each buffer, and associates the buffers with unique numerical IDs. + * + * IPAs shall map the dmabuf file handles to their address space and keep a + * cache of the mappings, indexed by the buffer numerical IDs. The IDs are used + * in all other IPA interface methods to refer to buffers, including the + * unmapBuffers() method. + * + * All buffers that the pipeline handler wishes to share with an IPA shall be + * mapped with this method. Buffers may be mapped all at once with a single + * call, or mapped and unmapped dynamically at runtime, depending on the IPA + * protocol. Regardless of the protocol, all buffers mapped at a given time + * shall have unique numerical IDs. + * + * The numerical IDs have no meaning defined by the IPA interface, and IPA + * protocols shall not give them any specific meaning either. They should be + * treated as opaque handles by IPAs, with the only exception that ID zero is + * invalid. + * + * \sa unmapBuffers() + * + * \todo Provide a generic implementation of mapBuffers and unmapBuffers for + * IPAs + */ + +/** + * \fn IPAInterface::unmapBuffers() + * \brief Unmap buffers shared by the pipeline to the IPA + * \param[in] ids List of buffer IDs to unmap + * + * This method removes mappings set up with mapBuffers(). Buffers may be + * unmapped all at once with a single call, or selectively at runtime, depending + * on the IPA protocol. Numerical IDs of unmapped buffers may be reused when + * mapping new buffers. + * + * \sa mapBuffers() + */ + +/** + * \fn IPAInterface::processEvent() + * \brief Process an event from the pipeline handler + * \param[in] data IPA operation data + * + * This operation is used by pipeline handlers to inform the IPA module of + * events that occurred during the on-going capture operation. + * + * The event notified by the pipeline handler with this method is handled by the + * IPA, which interprets the operation parameters according to the separately + * documented IPA protocol. + */ + +/** + * \var IPAInterface::queueFrameAction + * \brief Queue an action associated with a frame to the pipeline handler + * \param[in] frame The frame number for the action + * \param[in] data IPA operation data + * + * This signal is emitted when the IPA wishes to queue a FrameAction on the + * pipeline. The pipeline is still responsible for the scheduling of the action + * on its timeline. + * + * This signal is emitted by the IPA to queue an action to be executed by the + * pipeline handler on a frame. The type of action is identified by the + * \a data.operation field, as defined by the IPA protocol, and the rest of the + * \a data is interpreted accordingly. The pipeline handler shall queue the + * action and execute it as appropriate. + */ + } /* namespace libcamera */ -- cgit v1.2.1