TCRing: A Novel Single-Channel Deadlock-Free Concentrated on-Chip Network

On-chip network designed for modular System-on-Chip(SoC) has recent became a research hotspot, especially when methodology is employed rather than programmer experience. Most of the existing research relies on a specific topology, or modification to the subnet inside a module. In this paper, we propose TCRing, a novel concentrated network-on-chip. TCRing is a bi-directional ring with only three routers, but has the ability to mount one or more nodes on each router. Despite the fact that TCRing has only one channel, there is no deadlock problem. In addition, TCRing's simple architecture is friendly to physical layout. However, the low-complexity design does not compromise the flexibility and scalability of TCRing. An irregular modular SoC based on TCRing is given as an example in this paper. Based on the Booksim2.0 simulator, TCRing has 33% lower latency and 50% higher throughput than traditional concentrated rings in uniform traffic patterns. Besides, TCRing consistently maintains low latency in neighbor and randperm traffic at any injection rates. TCRing is capable of dispersing congestion traffic by enabling adaptive routing. Excitingly, irregular TCRing performs better than regular topology, indicated that it is capable of dealing with complex application scenarios. Design Compiler results show that TCRing saves 30% area and 20% power consumption.