FlexCore: Implementing an exposed datapath processor

Abstract

The FlexCore processor is the resulting implementation of an exposed datapath approach conceptualized in the FlexSoC programme. By way of a crossbar switch interconnect, all execution units in a FlexCore datapath can potentially communicate, allowing the inherent hardware parallelism to be utilized. This interconnect enables configuration of a datapath to match an application domain, for example, by way of datapath accelerators. The baseline FlexCore is a general-purpose processor (GPP) and since all FlexCore configurations are extensions to the baseline, they offer GPP functionality as complement to the domain-specific functionality. This paper gives an overview of the implementation of complete FlexCore processors, accompanied with discussions on datapath interconnects, datapath extensions and instruction decompression.