Adaptive Clock Management of HLS-generated Circuits on FPGAs

Abstract

In this article, we present Syncopation , a performance-boosting fine-grained timing analysis and adaptive clock management technique for High-Level Synthesis-generated circuits implemented on Field-Programmable Gate Arrays. The key idea is to use the HLS scheduling information along with the placement and routing results to determine the worst-case timing path for individual clock cycles. By adjusting the clock period on a cycle-by-cycle basis, we can increase performance of an HLS-generated circuit. Our experiments show that Syncopation improves performance by 3.2% (geomean) across all benchmarks (up to 47%). In addition, by employing targeted synthesis techniques along with Syncopation, we can achieve 10.3% performance improvement (geomean) across all benchmarks (up to 50%). Syncopation instrumentation is implemented entirely in soft logic without requiring alterations to the HLS-synthesis toolchain or changes to the FPGA, and has been validated on real hardware.