Uninterpreted co-simulation for performance evaluation of Hw/Sw systems

Performance modeling and evaluation of embedded hardware/software systems is important to help the CoDesign process. The hardware/software partitioning needs to be evaluated before synthesizing the solution. This paper presents a co-simulation technique based on the use of an uninterpreted model able to accurately represent the behavior of the whole system. The performance model includes two complementary viewpoints: the structural viewpoint which describes the functional structure, the hardware structure, the functional to hardware mapping, and the behavioral viewpoint which specifies the temporal evolution of each function or process. Attributes are added to the graphical model to specify the local properties of all components. The performance properties of the solution are obtained by simulation with VHDL. Software functions are executed according to the availability of an execution resource which simulates a microprocessor. This technique leads to rapidly obtain a lot of results by modifying appropriate parameters of the model, and so to easily scan the CoDesign space to decide on the best implementation. This modeling and estimation technique is fully integrated in a whole development process based on the MCSE methodology.