Mechanism for processor power state aware distribution of lowest priority interrupt

• US 7,191,349 B2
• Filed: 12/26/2002
• Issued: 03/13/2007
• Est. Priority Date: 12/26/2002
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Naveh, Alon, Kaushik, Shivnandan D., Crossland, James B., Horigan, John W.
• Primary Examiner(s): Trujillo; James K.
• Application Number:
  US10/330,622
• Publication Number:
  US 20040128563A1
• Time in Patent Office: 1,538 Days
• Field of Search: None
• US Class Current: 713/323
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/3243 Power saving in microcontroller unit
• CPC Class Codes: G06F 1/329 by task scheduling
• CPC Class Codes: G06F 9/3851 from multiple instruction streams, e.g. multistreaming
• CPC Class Codes: G06F 9/4812 by interrupt, e.g. masked
• CPC Class Codes: G06F 9/5094 where the allocation takes into account power or heat criteria power management in computers in general G06F1/3203; thermal management in computers in general G06F1/206
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

A method for a mechanism for processor power state aware distribution of lowest priority interrupts. The method of one embodiment comprises receiving first power state information from a first component and second power state information from a second component. First task priority information from the first component and second task priority from the second component are also received. An interrupt request from a first device for servicing is received. Power state and task priority information for the first and second components are evaluated to determine which component should service the interrupt request. Either the first component or the second component is selected to be a destination component to service the interrupt request based on the power state and task priority information. The interrupt request is communicated to the destination component.

Claims

1. A method comprising:

receiving first power state information from a first component, said first power state information being information representing the power state of said first component, and second power state information from a second component, said second power state information being information representing the power state of said second component;

receiving first task priority information from said first component and second task priority from said second component;

receiving an interrupt request from a first device for servicing;

evaluating power state and task priority information for said first and second components to determine which component should service said interrupt request;

selecting either said first component or said second component to be a destination component to service said interrupt request based on said power state and task priority information; and

communicating said interrupt request to said destination component.

2. The method of claim 1 further comprising storing said first power state information in a first memory location and said second power state information in a second memory location.

3. The method of claim 2 further comprising storing said first task priority information in a third memory location and said second task priority information in a fourth memory location.

4. The method of claim 3 further comprising checking devices for interrupt requests.

5. The method of claim 4 further comprising updating power state and task priority information for said destination component to reflect a ask priority of said interrupt request.

6. The method of claim 5 further comprising receiving notification of interrupt completion from said destination component.

7. The method of claim 6 further comprising restoring said power state and task priority information for said destination component to values that existed prior to servicing said interrupt request.

8. The method of claim 7 further comprising informing said device of said interrupt completion.

9. The method of claim 8 wherein said first and second components are processors.

10. The method of claim 9 wherein said first, second, third, and fourth memory locations are located within chipset logic.

11. An apparatus comprising:

interrupt handling logic coupled to a first set of signal lines to receive an interrupt request, said first set of signal lines coupled to one or more devices that can generate interrupt requests;

a bus interface to interact with a bus coupled to a first component and a second component, wherein said interrupt handling logic is coupled to said first bus through said bus interface to receive power state information and task priority information for each of said first and second components, said power state information being information representing the power state of said components;

evaluation logic coupled said interrupt handling logic, wherein when said interrupt handling logic receives said interrupt request, said evaluation logic is to evaluate power state and task priority information for said first and second components to determine which component should service said interrupt request; and

selection logic coupled to said evaluation logic to select either said first component or said second component to be a destination component to service said interrupt request based on said power state and task priority information.

12. The apparatus of claim 11 further comprising memory to store said power state information and said task priority information for each of said first and second components for reference by said evaluation logic.

13. The apparatus of claim 12 wherein said selection logic is to further communicate said interrupt request to said destination component for servicing.

14. The apparatus of claim 13 wherein said selection logic is to further update power state and task priority information for said destination component to reflect a task priority of said interrupt request.

15. The apparatus of claim 14 wherein said interrupt handling logic is to further receive notification of interrupt completion from said destination component.

16. The apparatus of claim 15 wherein said selection logic is to further restore said power state and task priority information for said destination component to values that existed prior to servicing said interrupt request.

17. The apparatus of claim 16 wherein interrupt handling logic is to further inform said device of said interrupt completion.

18. The apparatus of claim 17 wherein said first and second components are processors.

19. The apparatus of claim 17 wherein said first and second components execute threads of a multi-threading environment.

20. The apparatus of claim 19 wherein said apparatus is a chipset.

21. A system comprising:

a bus;

a first component and a second component coupled to said bus;

one or more system devices that can generate interrupt requests, wherein said interrupt requests require service from either said first or second component;

a chipset to handle said interrupt requests, said chipset coupled to said systems devices and to said first and second components, wherein said chipset is to receive power state information and task priority information for each of said first and second components, said power state information being information representing the power state of said first and second components, said chipset to evaluate said power state and task priority information when an interrupt request is received and to determine which component should service said interrupt request, and wherein said chipset selects either said first component or said second component to service said request based an said power state and task priority information.

22. The system of claim 21 wherein said chipset further comprises memory registers to store said power state information and said task priority information for each of said first and second components for reference by said evaluation logic.

23. The system of claim 22 wherein said chipset further comprises logic to update power state and task priority information for said destination component to reflect a task priority of said interrupt request.

24. The system of claim 22 wherein said chipset further comprises logic to track power state and task priority information for each of said first and second component.

25. The system of claim 22 wherein said chipset receives notification of completion of said interrupt request from a component selected to service said interrupt request.

26. The system of claim 25 wherein said chipset further comprises logic to restore said power state and task priority information for said component selected to service said interrupt request to values that existed prior to servicing said interrupt request.

27. The system of claim 26 wherein said first and second components are each multi-threading processors.

28. The system of claim 26 wherein said first and second components are each processing cores of a multi-core module.

29. A method comprising:

receiving first power state information from a first component, said first power state information being information representing the power state of said first component, and second power state information from a second component, said second power state information being information representing the power state of said second component;

assigning a first task priority value to said first component based on said first power state information;

assigning a second task priority value to said second component based on said second power state information;

receiving an interrupt request from a first device for servicing;

evaluating task priority values for said first and second components to determine which component should service said interrupt request;

selecting either said first component or said second component to be a destination component to service said interrupt request based on said task priority values; and

communicating said interrupt request to said destination component.

30. The method of claim 29 further comprising storing said first and second task priority values to a first and second registers.

31. The method of claim 30 wherein each power state information comprises a power state value.

32. The method of claim 31 wherein each power state value corresponds to a task priority value.

33. The method of claim 32 wherein a higher power state value corresponds to lower task priority value and a lower power state value corresponds to a higher task priority value.

34. The method of claim 33 a component with a lower task priority value is more preferably selected to be said destination component to service said interrupt request than another component with a higher task priority value.

35. The method of claim 34 wherein said first and second components are a first processor and a second processor, respectively.

36. The method of claim 35 wherein each of task priority values are stored to a unique register.