Advanced Micro Devices Corporation

Alex Branover

Maurice B Steinman

Frank P Helms

Jonathan Mercer Owen

Paul Mackey

Kurt Lewchuk

A processor can operate in three different modes. In an active mode, a first voltage is provided to the processor, where the first voltage is sufficient to allow the processor to execute instructions. In a low-power mode, a retention voltage is provided to the processor. The processor consumes less power in the retention mode than in the active mode. In addition, the processor can operate in a third mode, where a voltage is provided to the processor sufficient to allow the processor to process cache messages, such as coherency messages, but not execute other normal operations or perform normal operations at a very low speed relative to their performance in the active mode.

Data processing device with low-power cache access mode

A processor can operate in different power modes. In an active power mode, the processor executes software. In response to receiving a halt indication from the software, hardware at the processor evaluates bus transactions for the processor. If the bus transactions meet a heuristic, hardware places a processor core in a lower power mode, such as a retention mode. Because the bus transactions are evaluated by hardware, rather than by software, and the software is not required to perform handshakes and other protocols to place the processor in the lower power mode, the processor is able to place the processor core into the lower power mode more quickly, thereby conserving power.

Growing community of inventors

Brookline, MA, United States of America

Alex Branover