Simulation-based functional verification of dynamically reconfigurable systems

Abstract

Dynamically reconfigurable systems (DRS) implemented using field-programmable gate arrays (FPGAs) allow hardware logic to be partially reconfigured while the rest of the design continues to operate. By mapping multiple reconfigurable hardware modules to the same physical region of an FPGA, such systems are able to time-multiplex their modules at runtime and adapt themselves to changing execution requirements. This architectural flexibility introduces challenges for verifying system functionality. New simulation approaches are required to extend traditional simulation techniques to assist designers in testing and debugging the time-varying behavior of DRS. This article summarizes our previous work on ReSim, the first tool to allow cycle-accurate yet physically independent simulation of a DRS reconfiguring both its logic and state. Furthermore, ReSim-based simulation does not require changing the design for simulation purposes and thereby verifies the implementation-ready design instead of a variation of the design. We discuss the conflicting requirements of simulation accuracy and verification productivity in verifying DRS designs and describe our approach to resolve this challenge. Through a range of case studies, we demonstrate that ReSim assists designers in detecting fabric-independent bugs of DRS designs and helps to achieve verification closure of DRS design projects.