/* SPDX-License-Identifier: LGPL-2.1-or-later */ /* * Copyright (C) 2022, Google Inc. * * fc_queue.h - IPA Frame context queue */ #pragma once #include <stdint.h> #include <vector> #include <libcamera/base/log.h> namespace libcamera { LOG_DECLARE_CATEGORY(FCQueue) namespace ipa { template<typename FrameContext> class FCQueue; struct FrameContext { private: template<typename T> friend class FCQueue; uint32_t frame; }; template<typename FrameContext> class FCQueue { public: FCQueue(unsigned int size) : contexts_(size) { } void clear() { for (FrameContext &ctx : contexts_) ctx.frame = 0; } FrameContext &alloc(const uint32_t frame) { FrameContext &frameContext = contexts_[frame % contexts_.size()]; /* * Do not re-initialise if a get() call has already fetched this * frame context to preseve the context. * * \todo If the the sequence number of the context to initialise * is smaller than the sequence number of the queue slot to use, * it means that we had a serious request underrun and more * frames than the queue size has been produced since the last * time the application has queued a request. Does this deserve * an error condition ? */ if (frame != 0 && frame <= frameContext.frame) LOG(FCQueue, Warning) << "Frame " << frame << " already initialised"; else init(frameContext, frame); return frameContext; } FrameContext &get(uint32_t frame) { FrameContext &frameContext = contexts_[frame % contexts_.size()]; /* * If the IPA algorithms try to access a frame context slot which * has been already overwritten by a newer context, it means the * frame context queue has overflowed and the desired context * has been forever lost. The pipeline handler shall avoid * queueing more requests to the IPA than the frame context * queue size. */ if (frame < frameContext.frame) LOG(FCQueue, Fatal) << "Frame context for " << frame << " has been overwritten by " << frameContext.frame; if (frame == frameContext.frame) return frameContext; /* * The frame context has been retrieved before it was * initialised through the initialise() call. This indicates an * algorithm attempted to access a Frame context before it was * queued to the IPA. Controls applied for this request may be * left unhandled. * * \todo Set an error flag for per-frame control errors. */ LOG(FCQueue, Warning) << "Obtained an uninitialised FrameContext for " << frame; init(frameContext, frame); return frameContext; } private: void init(FrameContext &frameContext, const uint32_t frame) { frameContext = {}; frameContext.frame = frame; } std::vector<FrameContext> contexts_; }; } /* namespace ipa */ } /* namespace libcamera */