Processor specific BIOS interface for power management

• US 20070162776A1
• Filed: 01/09/2006
• Published: 07/12/2007
• Est. Priority Date: 01/09/2006
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Ritz, Andrew, Marshall, Allen, Carpenter, Todd
• Granted Patent: US 7,577,860 B2
• Time in Patent Office: Days
• US Class Current: 713/320
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

Processor power management capabilities that enable an operating system kernel to interact with a plurality of ACPI-compliant computing devices to manage processor power using a generic processor description is described. Specifications of power processor management capabilities of processor types are stored in data structures, i.e., objects. Each object contains a control value field and a control mask field and may also contain a status value field and a status mask field. The kernel loads a generic processor driver and objects for each processor type enabling the kernel to respond to power management events such as, but are not limited to, processor utilization and processor operating temperature events. In response to a power management event, the kernel calculates a desired processor performance state; sets bits in the control mask field to describe the desired processor performance state; and passes the control mask to the generic processor driver which controls the processor. Responses to power management events include, but are not limited to, adjusting processor voltage and/or adjusting processor frequency.

Claims

1. A method of managing processor, i.e., processor component, power using a generic processor driver BIOS interface, the method comprising:

(a) storing processor objects each associated with a type of processor, the processor objects including data that describes the processor power management policies of the associated type of processor, the processor objects containing a control mask field and control value field;

(b) identifying a processor;

(c) selecting the processor object associated with the identified processor component;

(d) loading a generic processor driver; and

(e) in response to a power management event;

(i) calculating the desired state of the processor component;

(ii) reading the control value data for the desired state of the processor component from the control value field in the selected processor object;

(iii) reading the control mask data from the control mask field in the selected processor object; and

(iv) passing the control mask data and control value data to the generic processor driver.

2. The method of claim 1 wherein the power management policies describe the power consumption of the processor component as controlled by a processor characteristic.

3. The method of claim 2 wherein the processor characteristic is voltage.

4. The method of claim 2 wherein the processor characteristic is frequency.

5. The method of claim 1 wherein the power management policies describe the operating temperature of the processor component as controlled by a processor characteristic.

6. The method of claim 5 wherein the processor characteristic is voltage.

7. The method of claim 5 wherein the processor characteristic is frequency.

8. The method of claim 1 wherein:

(a) the processor objects also contain a status value field and status mask field; and

(b) in response to a power management event;

(i) reading the status value data from the status value field and the status mask data from the status mask field that together describe the expected status of the processor component; and

(ii) passing the status value data and status mask data to the generic processor driver.

9. The method of claim 1 wherein the processor component is a plurality of similar processors.

10. The method of claim 1 wherein the processor component is a plurality of similar processor cores.

11. Computer-readable medium containing a data structure including an ACPI _PSS object with Control and Status quad word variables and a ControlMask variable of quad word length.

12. The computer-readable medium of claim 11 also including a StatusMask variable of quad word length.

17. The computer-readable medium of claim 11 wherein the power management policies describe the operating temperature of the processor component as controlled by a processor characteristic.

18. The computer-readable medium of claim 17 wherein the processor characteristic is voltage.

19. The computer-readable medium of claim 17 wherein the processor characteristic is frequency.

13. Computer-readable medium containing computer executable instructions that, when executed, manage processor, i.e., processor component, power using a generic processor driver by:

(a) storing processor objects each associated with a type of processor, the processor objects including data that describes the processor power management policies of the associated type of processor, the processor objects containing a control mask field;

(b) identifying a processor;

(c) selecting the processor object associated with the identified processor component;

(d) loading a generic processor driver; and

(e) in response to a power management event;

(i) calculating the desired state of the processor component;

(ii) reading the control value data for the desired state of the processor component from the control value field in the selected processor object;

(iii) reading the control mask data from the control mask field in the selected processor object; and

(iv) passing the control mask data and control value data to the generic processor driver.

14. The computer-readable medium of claim 13 wherein the power management policies describe the power consumption of the processor component as controlled by a processor characteristic.

15. The computer-readable medium of claim 14 wherein the processor characteristic is voltage.

16. The computer-readable medium of claim 14 wherein the processor characteristic is frequency.

20. The computer-readable medium of claim 13 wherein the processor component is a plurality of similar processors.