Method and system of power management for a data processing system

A power management architecture in a data processing system comprising physical devices having at least one state, each state has corresponding power value, and where a system state is defined as the set of all current states of the physical devices. Power objects and thermal objects, each corresponding to a physical device, contain information about the power requirements and thermal characteristics of each possible state for that physical device. The power and thermal objects also describe the allowed state transitions from each possible state to another state, and the power requirements and thermal characteristics of all possible state transitions. Also communicated is the current state of each physical device. Event means generate signals indicating the occurrence of an event in the system. A policy module contains rules, implementing the power management, that direct an action, the rules being a function of events and of power object information. A controller, in communication with the physical devices, the thermal and power objects, the event means, and the policy module, changes the state of any one of the physical devices in response to an event. The controller determines whether to change a physical device state based on the policy module rules.