The following figure illustrates the signals associated with the completer completion interface of the core. The core delivers each TLP on this interface as an AXI4-Stream packet.
Figure 1. Completer Completion Interface Signals
The core delivers each TLP on the Completer Completion (CC) interface as an AXI4-Stream packet. The packet starts with a 96-bit descriptor, followed by data in the case of Completions with a payload.
The CC interface supports two distinct data alignment modes. In the Dword-aligned mode, the first byte of valid data must be presented in lane n = (12 + A mod 4) mod w, where
A
is the byte-level
starting address of the data block being transferred (as conveyed in the Lower Address field
of the descriptor) and w the width of the interface in bytes (8, 16, or
32). In the address-aligned mode, the data always starts in a new beat after the descriptor
has ended. When transferring the Completion payload for a memory or I/O read request, its
first valid byte is on lane n = A mod
w. For all other Completions, the payload is aligned with byte lane
0.