The 10/100/1000 Mb/s Ethernet FIFO contains an
instance of tx_client_fifo to connect to the Ethernet
MAC TX AXI4-Stream interface, and an instance of the
rx_client_fifo to connect to the Ethernet MAC RX AXI4-Stream interface. Both transmit and receive FIFO
components implement an AXI4-Stream user interface through
which the frame data can be read and written. This module is present only when the AXI
Ethernet Subsystem is not configured in processor mode. In processor mode, the pattern
generator and checker read and write directly to the streaming interfaces.