A Scalable Methodology for Designing Efficient Interconnection Network of Chiplets.

The Chiplet methodology can accelerate VLSI system development and provide better flexibility. However, it is not easy to build interconnection networks across multiple chiplets and maintain high-performance deadlock-free routing in systems of various hierarchical topologies. In particular, most on-chiplet networks are based on flat topologies such as 2D-mesh, which are inflexible and insufficient for large-scale multi-chiplet systems.To take full advantage of the multi-chiplet architecture and advanced packaging, we propose an interconnection method that can flexibly establish high-radix interconnection networks from typical 2D-mesh-NoC-based chiplets. A minus-first-based deadlock-free adaptive routing algorithm and a safe/unsafe flow control policy are introduced for these multi-chiplet interconnection networks. Additionally, a general approach network interleaving is used to balance the communication bandwidth within and between chiplets.We evaluate different architectures and traffic patterns on a cycle-accurate C++ simulator. Compared with traditional adaptive routing in 2D-mesh, our methodology can significantly improve network performance in various cases. The more chiplets there are, the more effective the method is. For 64 4×4-2D-mesh-based chiplets, The maximum injection rate increase is up to 2×, and the average latency reduction is up to 45%.