SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
The SATA controller handles all of the transport layer functions of the SATA protocol. During reception it receives a frame information structure (FIS) from its link layer through the RX FIFO, decodes the type, and routes it to the proper location through the port DMA. During transmission it transfers a FIS constructed by the port DMA to the link layer through the TX FIFO. It also passes link layer errors and checks for transport layer errors to pass up to the system. The transport layer also contains the TX and RX FIFOs. These FIFOs are used as asynchronous data buffers between the serial domain and the bus clock domain. The size of these FIFOs affects the subsystem ability to buffer data before flow control must be asserted. It also affects the maximum transaction size that can be programmed into the port DMA.