Refactor of capture buffer management between cores.

Instead of copying data into and out of FIFO, passing buffer pointers between cores that are sized to match preferred/ideal SD card write size.

firmware/application/analog_audio_app.hpp

@@ -143,7 +143,7 @@ private:
 
 	RecordView record_view {
 		{ 0 * 8, 2 * 16, 30 * 8, 1 * 16 },
-		"AUD_????", RecordView::FileType::WAV, 12, 2,
+		"AUD_????", RecordView::FileType::WAV, 4096, 4
 	};
 
 	spectrum::WaterfallWidget waterfall;

firmware/application/capture_app.hpp

@@ -78,7 +78,7 @@ private:
 
 	RecordView record_view {
 		{ 0 * 8, 2 * 16, 30 * 8, 1 * 16 },
-		"BBD_????", RecordView::FileType::RawS16, 14, 1,
+		"BBD_????", RecordView::FileType::RawS16, 16384, 3
 	};
 
 	spectrum::WaterfallWidget waterfall;

firmware/application/capture_thread.cpp

@@ -31,20 +31,29 @@ public:
 	~StreamOutput();
 
 	size_t available() {
-		return fifo->len();
+		return fifo_buffers_full->len();
 	}
 
-	size_t read(void* const data, const size_t length) {
-		return fifo->out(reinterpret_cast<uint8_t*>(data), length);
+	StreamBuffer* get_buffer() {
+		StreamBuffer* p { nullptr };
+		fifo_buffers_full->out(p);
+		return p;
 	}
 
-	static FIFO<uint8_t>* fifo;
+	bool release_buffer(StreamBuffer* const p) {
+		p->empty();
+		return fifo_buffers_empty->in(p);
+	}
+
+	static FIFO<StreamBuffer*>* fifo_buffers_empty;
+	static FIFO<StreamBuffer*>* fifo_buffers_full;
 
 private:
 	CaptureConfig* const config;
 };
 
-FIFO<uint8_t>* StreamOutput::fifo = nullptr;
+FIFO<StreamBuffer*>* StreamOutput::fifo_buffers_empty = nullptr;
+FIFO<StreamBuffer*>* StreamOutput::fifo_buffers_full = nullptr;
 
 StreamOutput::StreamOutput(
 	CaptureConfig* const config
@@ -53,11 +62,13 @@ StreamOutput::StreamOutput(
 	shared_memory.baseband_queue.push_and_wait(
 		CaptureConfigMessage { config }
 	);
-	fifo = config->fifo;
+	fifo_buffers_empty = config->fifo_buffers_empty;
+	fifo_buffers_full = config->fifo_buffers_full;
 }
 
 StreamOutput::~StreamOutput() {
-	fifo = nullptr;
+	fifo_buffers_full = nullptr;
+	fifo_buffers_empty = nullptr;
 	shared_memory.baseband_queue.push_and_wait(
 		CaptureConfigMessage { nullptr }
 	);
@@ -69,9 +80,9 @@ Thread* CaptureThread::thread = nullptr;
 
 CaptureThread::CaptureThread(
 	std::unique_ptr<Writer> writer,
-	size_t write_size_log2,
-	size_t buffer_count_log2
-) : config { write_size_log2, buffer_count_log2 },
+	size_t write_size,
+	size_t buffer_count
+) : config { write_size, buffer_count },
 	writer { std::move(writer) }
 {
 	// Need significant stack for FATFS
@@ -90,29 +101,22 @@ CaptureThread::~CaptureThread() {
 void CaptureThread::check_fifo_isr() {
 	// TODO: Prevent over-signalling by transmitting a set of 
 	// flags from the baseband core.
-	const auto fifo = StreamOutput::fifo;
+	const auto fifo = StreamOutput::fifo_buffers_full;
 	if( fifo ) {
 		chEvtSignalI(thread, EVT_MASK_CAPTURE_THREAD);
 	}
 }
 
 msg_t CaptureThread::run() {
-	const size_t write_size = 1U << config.write_size_log2;
-	const auto write_buffer = std::make_unique<uint8_t[]>(write_size);
-	if( !write_buffer ) {
-		return false;
-	}
-
 	StreamOutput stream { &config };
 
 	while( !chThdShouldTerminate() ) {
-		if( stream.available() >= write_size ) {
-			if( stream.read(write_buffer.get(), write_size) != write_size ) {
-				return false;
-			}
-			if( !writer->write(write_buffer.get(), write_size) ) {
+		if( stream.available() ) {
+			auto buffer = stream.get_buffer();
+			if( !writer->write(buffer->data(), buffer->size()) ) {
 				return false;
 			}
+			stream.release_buffer(buffer);
 		} else {
 			chEvtWaitAny(EVT_MASK_CAPTURE_THREAD);
 		}

firmware/application/capture_thread.hpp

@@ -40,8 +40,8 @@ class CaptureThread {
 public:
 	CaptureThread(
 		std::unique_ptr<Writer> writer,
-		size_t write_size_log2,
-		size_t buffer_count_log2
+		size_t write_size,
+		size_t buffer_count
 	);
 	~CaptureThread();
 

firmware/application/ui_record_view.cpp

@@ -139,13 +139,13 @@ RecordView::RecordView(
 	const Rect parent_rect,
 	std::string filename_stem_pattern,
 	const FileType file_type,
-	const size_t buffer_size_k,
-	const size_t buffer_count_k
+	const size_t write_size,
+	const size_t buffer_count
 ) : View { parent_rect },
 	filename_stem_pattern { filename_stem_pattern },
 	file_type { file_type },
-	buffer_size_k { buffer_size_k },
-	buffer_count_k { buffer_count_k }
+	write_size { write_size },
+	buffer_count { buffer_count }
 {
 	add_children({ {
 		&button_record,
@@ -222,7 +222,7 @@ void RecordView::start() {
 		button_record.set_bitmap(&bitmap_stop);
 		capture_thread = std::make_unique<CaptureThread>(
 			std::move(writer),
-			buffer_size_k, buffer_count_k
+			write_size, buffer_count
 		);
 	}
 }

firmware/application/ui_record_view.hpp

@@ -46,8 +46,8 @@ public:
 		const Rect parent_rect,
 		std::string filename_stem_pattern,
 		FileType file_type,
-		const size_t buffer_size_k,
-		const size_t buffer_count_k
+		const size_t write_size,
+		const size_t buffer_count
 	);
 	~RecordView();
 
@@ -73,8 +73,8 @@ private:
 
 	const std::string filename_stem_pattern;
 	const FileType file_type;
-	const size_t buffer_size_k;
-	const size_t buffer_count_k;
+	const size_t write_size;
+	const size_t buffer_count;
 	size_t sampling_rate { 0 };
 	SignalToken signal_token_tick_second;