Patent ID: 6883102

Claim:
A data processing apparatus, comprising: a processor for executing data processing instructions including power management instructions, at least one of said power management instructions being a command power management instruction; a power management controller for receiving command data from the processor when a command power management instruction is executed by the processor, and to control power management logic to perform an associated set of power management functions dependent on said command data; first power management logic controllable by the power management controller; the power management controller having an interface to enable communication with additional power management logic; the processor being arranged when executing said command power management instruction to specify within said command data provided to the power management controller whether an emulation mode of operation is set, said power management controller being arranged when said emulation mode is not set to initiate said associated set of power management functions dependent on said command data, and being arranged when said emulation mode is set to only initiate a subset of said associated set of power management functions not requiring communication over said interface.