Design and Applications for Embedded Networks-on-Chip on FPGAs

Field-programmable gate-arrays (FPGAs) have evolved to include embedded memory, high-speed I/O interfaces and processors, making them both more efficient and easier-to-use for compute acceleration and networking applications. However, implementing on-chip communication is still a designer’s burden wherein custom system-level buses are implemented using the fine-grained FPGA logic and interconnect fabric. Instead, we propose augmenting FPGAs with an embedded network-on-chip (NoC) to implement system-level communication. We design custom interfaces to connect a packet-switched NoC to the FPGA fabric and I/Os in a configurable and efficient way and then define the necessary conditions to implement common FPGA design styles with an embedded NoC. Four application case studies highlight the advantages of using an embedded NoC. We show that access latency to external memory can be $\sim$ 1.5 $\times$ lower. Our application case study with image compression shows that an embedded NoC improves frequency by 10-80%, reduces utilization of scarce long wires by 40% and makes design easier and more predictable. Additionally, we leverage the embedded NoC in creating a programmable Ethernet switch that can support up to 819 Gb/s-5 $\times$ more switching bandwidth and 3 $\times$ lower area compared to previous work. Finally, we design a 400 Gb/s NoC-based packet processor that is very flexible and more efficient than other FPGA-based packet processors.