Performance features of the PA7100 microprocessor

Abstract

The PA7100 CPU, the first precision-architecture, reduced-instruction-set-computer (PA-RISC) architecture implementation to combine an integer core and floating-point coprocessor into a single-chip format, is described. It incorporates superscalar execution and supports clock rates of up to 100 MHz in standard 0.8- mu m CMOS. Features such as a flexible primary cache organization and multiprocessing capability allow the device to be scaled to a variety of system applications, price ranges, and performance levels. The microprocessor instruction execution pipeline, cache design, translation look-aside buffer (TLB) for virtual address translation, floating-point unit, and system interface bus are discussed. The design, test, and verification methods used in the development of the PA7100 are reviewed.