Abstract: A method and apparatus for interfacing dynamic hardware power managed blocks and software power managed blocks is disclosed. In one embodiment, and integrated circuit (IC) may include a number of power manageable functional units. The functional units maybe power managed through hardware, software, or both. Each of the functional units may be coupled to at least one other functional unit through a direct communications link. A link state machine may monitor each of the communications links between functional units, and may broadcast indications of link availability to the functional units coupled to the link. Responsive to a software request to shut down a given link, or a hardware initiated shutdown of one of the functional units coupled to the link, the link state machine may broadcast and indication that the link is unavailable.

Abstract: A method and apparatus for dynamic clock and power gating and decentralized wakeups is disclosed. In one embodiment, an integrated circuit (IC) includes power-manageable functional units and a power management unit. Each of the power manageable functional units is configured to convey a request to enter a low power state to the power management unit. The power management unit may respond by causing a requesting functional unit to enter the low power state. Should another functional unit initiate a request to communicate with a functional unit currently in the low power state, it may send a request to that functional unit. The receiving functional unit may respond to the request by exiting the low power state and resuming operation in the active state.

Abstract: Circuits, methods, and apparatus that allow the elimination of a frame buffer connected directly to a graphics processing unit. The graphics processing unit includes an on-chip memory. Following system power-up or reset, the GPU initially renders comparatively low-resolution images to the on-chip memory for display. Afterward, the GPU renders images, which are typically higher resolution, and stores them in a system memory, apart from the graphics processing unit. The on-chip memory, which is no longer needed for image storage, instead stores address information, referred to as page tables, identifying the location of data stored by the GPU in the separate system memory.