Device drivers should not do power management

We argue that device drivers are not the best place to implement power management policies for components on a system-on-a-chip (SoC). We present empirical evidence that device driver developers are inadequately implementing power management and show the information needed for good power management policies is available outside the device drivers. We implement a software central agent to infer the needed information and accomplish power management without device driver support. We further show that simple hardware support can eliminate the overhead of our approach and extend it to support all SoC components.