FORCED IDLE OF A DATA PROCESSING SYSTEM

• US 20090177422A1
• Filed: 01/07/2008
• Published: 07/09/2009
• Est. Priority Date: 01/07/2008
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Conroy, David G., Culbert, Michael, Cox, Keith
• Granted Patent: US 7,949,888 B2
• Time in Patent Office: Days
• US Class Current: 702/64
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/3237 by disabling clock generation or distribution
• CPC Class Codes: G06F 1/324 by lowering clock frequency
• CPC Class Codes: G06F 1/3296 by lowering the supply or operating voltage
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

Exemplary embodiments of methods and apparatuses to manage a power of a data processing system are described. A constraint parameter of a system operating at a first frequency and a first voltage is monitored. The system is, based on the monitoring of the constraint parameter, forced into an idle state while operating at a second frequency and a second voltage. The idle state prevents instructions from being executed.

Claims

1. A machine-implemented method, comprising:

monitoring a constraint parameter of a system operating at a first frequency and a first voltage;

forcing the system into an idle state while the system operates at a second frequency and a second voltage, lower than the first voltage, wherein the idle state prevents instructions from being executed and wherein the forcing is based on the monitoring of the constraint parameter.

2. The machine-implemented method of claim 1 wherein the second frequency is less than the first frequency.

3. The machine-implemented method of claim 1, further comprising:

determining a rate of forcing the system into the idle state.

4. The machine-implemented method of claim 1, further comprising:

determining whether the constraint parameter is greater than a constraint parameter threshold;

determining whether the first voltage is a minimum voltage; and

forcing the system into the idle state if the first voltage is the minimum voltage and the constraint parameter is greater than the constraint parameter threshold.

5. The machine-implemented method of claim 4, further comprising:

decreasing an operating point of the system if the system does not operate at the minimum voltage and the constraint parameter is greater than the constraint parameter threshold.

6. The machine-implemented method of claim 1, wherein the constraint parameter is a power, a temperature, a current, a battery load, or any combination thereof and the second frequency is greater than zero and is less than the first frequency and wherein the second voltage is greater than zero and is less than the first voltage.

7. The machine-implemented method of claim 1, further comprising:

determining a percentage of the idle state for the system operating at the first frequency and the first voltage based on the constraint parameter and wherein the second frequency is zero and the second voltage is zero for at least a portion of the system.

8. A data processing system, comprising:

a processor,

a memory, coupled to the processor;

one or more sensors coupled to the processor to monitor a constraint parameter of a system operating at a first frequency and a first voltage, wherein the processor is configured to force the system into an idle state while the system operates at a second frequency and a second voltage which is lower than the first voltage, wherein the idle state prevents instructions from being executed and wherein the processor forces the system into the idle state based on monitoring of the constraint parameter.

9. The data processing system of claim 8, wherein the second frequency is less than the first frequency.

10. The data processing system of claim 8, wherein the processor is further configured to

determine a rate of forcing the system into the idle state.

11. The data processing system of claim 8, wherein the processor is further configured to

determine whether the constraint parameter is greater than a constraint parameter threshold, determine whether the first voltage is a minimum voltage, and force the system into the idle state if the first voltage is the minimum voltage and the constraint parameter is greater than the constraint parameter threshold.

12. The data processing system of claim 11, wherein the processor is further configured to

decrease an operating point of the system if the system does not operate at the minimum voltage and the constraint parameter is greater than the constraint parameter threshold.

13. The data processing system of claim 8, wherein the processor is further configured to

determine a percentage of the idle state for the system operating at the first frequency and the first voltage based on the constraint parameter and wherein the second frequency is zero and the second voltage is zero for at least a portion of the processor.

14. The data processing system of claim 8, wherein the memory stores information about when and how to force the system into the idle state.

15. The data processing system of claim 8, wherein the constraint parameter is a power, a temperature, a current, a battery load, or any combination thereof and wherein the second frequency is greater than zero and is less than the first frequency and wherein the second voltage is greater than zero and is less than the first voltage.

16. A machine-readable storage medium storing executable program instructions which cause a data processing system to perform operations comprising:

monitoring a constraint parameter of the system operating at a first frequency and a first voltage;

forcing the system into an idle state while the system operates at a second frequency and a second voltage which is lower than the first voltage, wherein the idle state prevents instructions from being executed and wherein the forcing is based on the monitoring of the constraint parameter.

17. The machine-readable medium of claim 16, wherein the second frequency is less than the first frequency.

18. The machine-readable medium of claim 16, further including instructions that cause the data processing system to perform operations comprising:

determining a rate of forcing the system into the idle state.

19. The machine-readable medium of claim 16, further including instructions that cause the data processing system to perform operations comprising:

determining whether the constraint parameter is greater than a constraint parameter threshold;

determining whether first voltage is a minimum voltage; and

forcing the system into the idle state if the first voltage is the minimum voltage and the constraint parameter is greater than the constraint parameter threshold.

20. The machine-readable medium of claim 19, further including instructions that cause the data processing system to perform operations comprising:

decreasing an operating point of the system if the system does not operate at the minimum voltage and the constraint parameter is greater than the constraint parameter threshold.

21. The machine-readable medium of claim 16, further including instructions that cause the data processing system to perform operations comprising:

determining a percentage of the idle state for the system operating at the first frequency and the first voltage based on the constraint parameter and wherein the second frequency is zero and the second voltage is zero for at least a portion of the system.

22. The machine-readable medium of claim 16, wherein the constraint parameter is a power, a temperature, a current, a battery load, or any combination thereof and wherein the second frequency is greater than zero and is less than the first frequency and wherein the second voltage is greater than zero and is less than the first voltage.

23. A data processing system, comprising:

means for monitoring a constraint parameter of the system operating at a first frequency and a first voltage;

means for forcing the system into an idle state while the system operates at a second frequency and a second voltage which is lower than the first voltage, wherein the idle state prevents instructions from being executed and wherein the forcing is based on the monitoring of the constraint parameter.

24. The data processing system of claim 23, further comprising:

means for determining whether the constraint parameter is greater than a constraint parameter threshold;

means for determining whether the first voltage is a minimum voltage; and

means for forcing the system into the idle state if the first voltage is the minimum voltage and the constraint parameter is greater than the constraint parameter threshold.

25. The data processing system of claim 23, further comprising:

means for determining a percentage of the idle state for the system operating at the first frequency and the first voltage based on the constraint parameter, and wherein the second frequency is greater than zero and is less than the first frequency and wherein the second voltage is greater than zero and is less than the first voltage.