Power Management of Voltage/Frequency Island-Based Systems Using Hardware-Based Methods

Shrinking technology nodes combined with the need for higher clock speeds have made it increasingly difficult to distribute a single global clock across a chip while meeting the power requirements of the design. Globally asynchronous locally synchronous (GALS) design style can help achieve low power consumption and modularity of a design while greatly reducing the number of global interconnects. Such multiple clock domain architectures can benefit from having frequency/voltage values assigned to each domain based on workload requirements. The work presented in this paper proposes a new
hardware-based
approach to dynamically change the frequencies and potentially voltages of a voltage-frequency island (VFI) system driven by a dynamic workload. This technique tries to change the frequency of a synchronous island such that it will have efficient power utilization while satisfying performance constraints. In recent years, there have been major developments, both in industry and academia, in the field of multiprocessor systems. Such multiprocessor systems are very good candidates for VFI design style implementation, where one or more processors can be part of a single VFI. To demonstrate the feasibility of our proposed method, we have implemented a multiprocessor system for a field-programmable gate array (FPGA) platform that uses independently generated clocks for each processor. The results from the FPGA platform confirm the claim that the power consumption of a system can potentially be reduced while maintaining the performance of many applications. Our work concentrates primarily on embedded systems, but the idea can be explored for general-purpose computing as well.