Performance estimation and verification for hardware/software co-design using GEZEL and OMAP platforms

In this paper, we propose an approach of performance estimation for HW/SW co-design using the GEZEL co-simulation environment. We also implement the design with the OMAP platform and verify the result of co-simulation for accuracy of performance estimation. We use the GNU gprof utility to analyze the source code and take advantage of SystemC or GEZEL to design hardware modules for the most time-consuming block. The hardware and software co-simulation is achieved by using the interface provided by GEZEL to link hardware and software modules. Also we have compared the co-simulation result with the actual execution of the hardware/software implementation in the OMAP platform. We are successful in implementing the FIR (Finite Impulse Response) Filter on OMAP5912 which contains ARM and DSP dual-processor. The result is coincided with the co-simulation done by the GEZEL envrionment. On the OMAP platform, we use the DSP Gateway to bridge hardware and software modules. Communication overheads are raised by the architecture of the operating system, where the upper layer software modules need to communicate with lower layer hardware modules via system calls and drivers. Thus, we have to consider the overheads of communications and context switches. We measure the communication overhead of the DSP Gateway for read and write operations. Through this proposed methods, we are able to acquire high accuracy of performance estimation for HW/SW co-design.