Multiway FPGA partitioning by fully exploiting design hierarchy

Abstract

In this paper, we present a new integrated synthesis and partitioning method for multiple-FPGA applications. Our approach bridges the gap between HDL synthesis and physical partitioning by fully exploiting the design hierarchy. We propose a novel multiple-FPGA synthesis and partitioning method which is performed in three phases: (1) fine-grained synthesis, (2) functional-based clustering, and (3) hierarchical set-covering partitioning. This method first synthesizes a design specification in a fine-grained way so that functional clusters can be preserved based on the structural nature of the design specification. Then, it applies a hierarchical set-covering partitioning method to form the final FPGA partitions. Experimental results on a number of benchmarks and industrial designs demonstrate that I/O limits are the bottleneck for CLB utilization when applying a traditional multiple-FPGA synthesis method on flattened netlists. In contrast, by fully exploiting the design structural hierarchy during the multiple-FPGA partitioning, our proposed method produces fewer FPGA partitions with higher CLB and lower I/O-pin utilizations.