Method and apparatus for managing global chip power on a multicore system on chip

• US 9,671,844 B2
• Filed: 09/26/2013
• Issued: 06/06/2017
• Est. Priority Date: 09/26/2013
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: Cavium, LLC (Marvell Technology Group Limited)
• Inventors: Carlson, David A., Kessler, Richard E.
• Primary Examiner(s): Abbaszadeh, Jaweed A
• Assistant Examiner(s): DESAI, SUMIL MANUBHAI
• Application Number:
  US14/038,549
• Publication Number:
  US 20150089251A1
• Time in Patent Office: 1,349 Days
• Field of Search: 713300
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: G06F 1/28 Supervision thereof, e.g. detecting power-supply failure by out of limits supervision
• CPC Class Codes: G06F 1/324 by lowering clock frequency
• CPC Class Codes: G06F 1/3243 Power saving in microcontroller unit
• CPC Class Codes: H04B 17/20 of receivers
• CPC Class Codes: H04L 2027/0016 Stabilisation of local oscillators
• CPC Class Codes: H04L 2027/0067 Phase error detectors
• CPC Class Codes: H04L 2027/0075 Error weighting
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

According to at least one example embodiment, a method and corresponding apparatus for controlling power in a multi-core processor chip include: accumulating, at a controller within the multi-core processor chip, one or more power estimates associated with multiple core processors within the multi-core processor chip. A global power threshold is determined based on a cumulative power estimate, the cumulative power estimate being determined based at least in part on the one or more power estimates accumulated. The controller causes power consumption at each of the core processors to be controlled based on the determined global power threshold. The controller may directly control power consumption at the core processors or may command the core processors to do so.

Claims

1. A method for controlling power consumption in a multi-core processor chip, the method comprising:

accumulating, at a central controller within the multi-core processor chip, one or more power estimates associated with multiple core processors within the multi-core processor chip, the accumulating including sending a read command from the central controller to at least one core processor of the multiple core processors and wherein the at least one core processor receiving the read command from the central controller updates a parameter value of the read command representing a cumulative sum of power estimates to produce an updated cumulative sum and forwards the read command with the updated cumulative sum to one other core processor or to the central controller;

determining a global power threshold based on a cumulative power estimate, the cumulative power estimate being determined based at least in part on the one or more power estimates accumulated; and

causing power consumption at each core processor to be controlled based on the global power threshold determined;

wherein determining the global power threshold includes;

adjusting a parameter value representing the global power threshold based on the cumulative power estimate determined and a corresponding average over time, relative to a desired target power.

2. The method according to claim 1, wherein accumulating the one or more power estimates associated with multiple core processors includes receiving one or more cumulative sums of power estimates associated with one or more subsets of the multiple core processors within the multi-core processor chip.

3. The method according to claim 1, wherein accumulating the one or more power estimates associated with multiple core processors includes receiving multiple power estimates corresponding to the multiple core processors within the multi-core processor chip.

4. The method according to claim 1, wherein adjusting the parameter value representing the global power threshold includes:

increasing the parameter value representing the global power threshold upon determining that the cumulative power estimate determined and the corresponding average over time are both smaller than the desired target power.

5. The method according to claim 1, wherein the desired target power is a constant set by a user or a manufacturer of the multi-core processor chip.

6. The method according to claim 1, wherein the desired target power is dynamically set based at least in part on measured temperature values of the multi-core processor chip.

7. The method according to claim 1 further comprising:

accumulating one or more representations of clock activities associated with one or more coprocessor blocks within the multi-core processor chip; and

determining one or more power estimates associated with the one or more coprocessor blocks based at least in part on the one or more representations accumulated,

wherein determining the cumulative power estimate for the multi-core processor chip is further based on the one or more power estimates associated with the one or more coprocessor blocks.

8. The method according to claim 7, wherein determining the one or more power estimates associated with the one or more coprocessor blocks is further based on a lookup table.

9. The method according to claim 7, wherein accumulating the one or more representations of the clock activities associated with the one or more coprocessor blocks includes:

counting, at each coprocessor block, clock activity cycles associated with the same coprocessor block;

generating a representation of the clock activity associated with the coprocessor block by mapping a predefined number of counted clock activity cycles into a single symbol within the representation of the clock activity associated with the coprocessor block; and

receiving, by the central controller, the representation of the clock activity associated with the coprocessor block.

10. The method according to claim 1, wherein causing power consumption at each core processor to be controlled includes instructing each core processor to control power consumption of the core processor based on the global power threshold.

11. The method according to claim 10, wherein instructing each core processor to control power consumption includes sending an indication of the global power threshold determined to each core processor.

12. The method according to claim 11, further comprising comparing, by each core processor, the global power threshold with a local power limit.

13. The method according to claim 1, wherein causing power consumption at each core processor to be controlled includes adjusting a master clock frequency.

27. The method according to claim 1, wherein adjusting the parameter value representing the global power threshold includes:

decreasing the parameter value representing the global power threshold upon determining that the cumulative power estimate determined is larger than the desired target power.

14. A multi-core processor chip comprising:

multiple core processors; and

a central controller coupled to at least one of the multiple core processors, the central controller configured to;

accumulate one or more power estimates associated with the multiple core processors within the multi-core processor chip, wherein in accumulating the one or more power estimates associated with the multiple core processors, the central controller is configured to send a read command from the central controller to at least one core processor of the multiple core processors;

wherein the at least one core processor from the multiple core processors is configured to;

receive the read command;

update a parameter value representing a cumulative sum of power estimates to produce an updated cumulative sum; and

forward the read command with the updated cumulative sum to one other core processor or to the central controller,

determine a global power threshold based on a cumulative power estimate, the cumulative power estimate being determined based at least in part on the one or more power estimates accumulated; and

cause power consumption at each core processor to be controlled based on the global power threshold determined;

wherein in determining the global power threshold, the central controller is configured to;

adjust a parameter value representing the global power threshold based on the cumulative power estimate determined and a corresponding average over time relative to a desired target power.

15. The multi-core processor chip according to claim 14, wherein in accumulating the one or more power estimates associated with the multiple core processors, the central controller is configured to receive one or more cumulative sums of power estimates associated with one or more subsets of the multiple core processors.

16. The multi-core processor chip according to claim 14, wherein in accumulating the one or more power estimates associated with the multiple core processors, the central controller is configured to receive multiple power estimates corresponding to the multiple core processors.

17. The multi-core processor chip according to claim 14, wherein in adjusting the parameter value representing the global power threshold, the central controller is configured to:

increase the parameter value representing the global power threshold upon determining that the cumulative power estimate determined and the corresponding average over time are both smaller than the desired target power.

18. The multi-core processor chip according to claim 14, wherein the desired target power is a constant set by a user or a manufacturer of the multi-core processor chip.

19. The multi-core processor chip according to claim 14, wherein the desired target power is dynamically set based at least in part on measured temperature values of the multi-core processor chip.

20. The multi-core processor chip according to claim 14, wherein the multi-core processor chip further includes one or more coprocessor blocks, and the central controller is further configured to:

accumulate one or more representations of clock activities associated with the one or more coprocessor blocks; and

determine one or more power estimates associated with the one or more coprocessor blocks based at least in part on the one or more representations accumulated,

wherein determining the cumulative power estimate for the multi-core processor chip is further based on the one or more power estimates associated with the one or more coprocessor blocks.

21. The multi-core processor chip according to claim 20, wherein in determining the one or more power estimates associated with the one or more coprocessor, blocks the central controller is further configured to check a lookup table to determine the power estimate associated with each coprocessor block.

22. The multi-core processor chip according to claim 20, wherein in accumulating one or more representations of the clock activities associated with the one or more coprocessor blocks, each coprocessor block is configured to:

count, at each coprocessor block, clock activity cycles associated with the same coprocessor block;

generate a representation of the clock activity associated with the coprocessor block by mapping a predefined number of counted clock activity cycles into a single symbol within the representation of the clock activity associated with the coprocessor block; and

send the representation of the clock activity associated with the coprocessor block to the central controller.

23. The multi-core processor chip according to claim 14, wherein in causing power consumption at each core processor to be controlled, the central controller is further configured to instruct each core processor to control power consumption of the core processor based on the global power threshold.

24. The multi-core processor chip according to claim 23, wherein in instructing each core processor to control power consumption, the central controller is further configured to send an indication of the global power threshold determined to each core processor.

25. The multi-core processor chip according to claim 24, wherein each core processor is configured to compare the global power threshold with a local power limit.

26. The multi-core processor chip according to claim 14, wherein in causing power consumption at each core processor to be controlled, the central controller is configured to adjust a master clock frequency.

28. The multi-core processor chip according to claim 14, wherein in adjusting the parameter value representing the global power threshold, the central controller is configured to:

decrease the parameter value representing the global power threshold upon determining that the cumulative power estimate determined is larger than the desired target power.