Initialization: Upon power-up, the ACP HDA Node performs a reset sequence. It asserts reset signals to the codec and waits for the codec to initialize. The node then reads the codec's Vendor ID and Device ID via the HDA link to identify the hardware.
Buffer Management: The node utilizes the BDL (Buffer Descriptor List) to know where audio samples reside in system memory. The DMA controller traverses this list cyclically to read or write samples.