FLEXBUS: a high-performance system-on-chip communication architecture with a dynamically configurable topology

In this paper, we describe FLEXBUS, a flexible, high-performance on-chip communication architecture featuring a dynamically configurable topology. FLEXBUS is designed to detect run-time variations in communication traffic characteristics, and efficiently adapt the topology of the communication architecture, both at the system-level, through dynamic bridge by-pass, as well as at the component-level, using component re-mapping. We describe the FLEXBUS architecture in detail and present techniques for its run-time configuration based on the characteristics of the on-chip communication traffic. The techniques underlying FLEXBUS can be used in the context of a variety of on-chip communication architectures. In particular, we demonstrate its application to AMBA AHB, a popular commercial on-chip bus. Detailed experiments conducted on the FLEXBUS architecture using a commercial design flow, and its application to an IEEE 802.11 MAC processor design, demonstrate that it can provide significant performance gains as compared to conventional architectures (up to 31.5% in our experiments), with negligible hardware overhead.