A spectral clustering approach to application-specific Network-on-Chip synthesis

Modern System-on-Chip (SoC) design relies heavily on efficient interconnects like Networks-on-Chip (NoCs). They provide an effective, flexible and cost efficient way of communication exchange between the individual processing elements of the SoC. Therefore, the choice of topology and design of the NoC itself plays a crucial role in the performance of the system. Depending on the field of application, standard topologies like meshes, fat-trees, and tori might be suboptimal in terms of power consumption, latency and area. This calls for a custom topology design methodology, which is based on the requirements imposed by the application, function and the use-cases of the SoC in question. This work proposes a fast approach, which uses spectral clustering and cluster ensembles to partition the system using normalized cuts and insert the necessary routers. Then, by using delay-constrained minimum spanning trees, links between the individual routers are created, such that any present latency constraints are satisfied at minimum cost. Results from applying the methodology to a smartphone SoC are presented.