Design verification of complex microprocessors

Abstract

As the complexity of microprocessors increases, functional verification becomes more difficult and emerges as the bottleneck of the design cycle. In this paper, vie suggest a functional verification methodology, especially for compatible microprocessor designs. To guarantee perfect compatibility with previous microprocessors, we developed three C models in different abstraction levels, i.e. Polaris, MCV and StreC. An instruction behavioral level C model (Polaris) is verified using the slowed-down PC. In the implementation of micro-architecture, a micro-operational level model (MCV) and RTL modal (StreC) are cc-simulated with consistency checking between these two models. The simulation speed of C models makes it possible to test the "real-world" application programs on the RTL design with a software board model (VPC). To increase the confidence level of verifications, Profiler reports the verification coverage of the test program, which is fed-back to the automatic test program generator (Pandora). The Restartability feature also helps to significantly reduce the total simulation time. Using the proposed verification methodology, we designed and verified the HK486, an Intel 80486 pin-compatible microprocessor successfully.