Torch: A Design Tool For Routing Channel Segmentation In Fpgas

A design tool for routing channel segmentation in island-style FPGAs is presented. Given the FPGA architecture parameters and a set of benchmark designs, the tool optimizes routing channel segmentation using the average interconnect power-delay product as a performance metric, which is estimated from placed and routed designs. A simulated-annealing procedure is used, whereby segmentation is incrementally changed in each iteration, the benchmark designs are mapped using VPR, and the performance metric is computed to decide whether to accept or reject the new segmentation. Run time is significantly reduced by using incremental routing in each iteration and parallelizing the metric evaluation. Experimental results using the MCNC benchmark designs demonstrate an average of 22% and 15% reduction in delay and power relative to a baseline segmentation. The results also show that average segment length should decrease with technology scaling. Finally, we demonstrate how the tool can be used to optimize other aspects of programmable routing in an FPGA