Distributed look-ahead routing in network-on-chip

Abstract

Embodiments herein describe an integrated circuit that includes a network on chip (NoC) where an egress logic block or switch performs a route lookup for a subsequent (e.g., downstream) switch in the NoC (referred to herein as look-ahead routing). After receiving the packet and a port ID from the egress logic block or the switch, the downstream switch knows, without performing route lookup of its own, on which port it should forward the packet. Thus, if the downstream switch performs other functions that are dependent on knowing the destination port (e.g., arbitration or QoS updating), the downstream switch can perform those functions immediately since the port ID was already determined by, and received from, the previous network element.