A design methodology for application-specific networks-on-chip

Abstract

With the help of HW/SW codesign, system-on-chip (SoC) can effectively reduce cost, improve reliability, and produce versatile products. The growing complexity of SoC designs makes on-chip communication subsystem design as important as computation subsystem design. While a number of codesign methodologies have been proposed for on-chip computation subsystems, many works are needed for on-chip communication subsystems. This paper proposes application-specific networks-on-chip (ASNoC) and its design methodology. ASNoC is used for two high-performance SoC applications. The methodology (1) can automatically generate optimized ASNoC for different applications, (2) can generate a corresponding distributed shared memory along with an ASNoC, (3) can use both recorded and statistical communication traces for cycle-accurate performance analysis, (4) is based on standardized network component library and floorplan to estimate power and area, (5) adapts an industrial-grade network modeling and simulation environment, OPNET, which makes the methodology ready to use, and (6) can be easily integrated into current HW/SW codesign flow. Using the methodology, ASNoC is generated for a H.264 HDTV decoder SoC and Smart Camera SoC. ASNoC and 2D mesh networks-on-chip are compared in performance, power, and area in detail. The comparison results show that ASNoC provide substantial improvements in power, performance, and cost compared to 2D mesh networks-on-chip. In the H.264 HDTV decoder SoC, ASNoC uses 39% less power, 59% less silicon area, 74% less metal area, 63% less switch capacity, and 69% less interconnection capacity to achieve 2X performance compared to 2D mesh networks-on-chip.