ITS AXI4-Stream interface
The ITS AXI4-Stream interface is a bi-directional AXI4-Stream interface of either 16-bit or 64-bit width for communication between the ITS and the GIC Distributor components on the same chip.
Arm expects a typical distributed system to be 16 bits wide. When a pre-existing wide interconnect is used, the 64-bit option allows messages to be efficiently packed.
The interface is fully credited so all messages can be accepted without dependency on any other ports.