Method, system, and apparatus for a plurality of slave devices determining whether to adjust their power state based on broadcasted power state data

• US 7,707,437 B2
• Filed: 05/03/2006
• Issued: 04/27/2010
• Est. Priority Date: 05/03/2006
• Status: Active Grant

• Current Assignee: Microchip Technology Incorporated
• Original Assignee: Standard Microsystems Corporation (Microchip Technology Incorporated)
• Inventors: Berenbaum, Alan D., Weiss, Raphael
• Primary Examiner(s): Lee; Thomas
• Assistant Examiner(s): Abbaszadeh; Jaweed A
• Application Number:
  US11/417,855
• Publication Number:
  US 20070260901A1
• Time in Patent Office: 1,455 Days
• Field of Search: 713/300, 713/323, 709/208, 709/253
• US Class Current: 713/300
• CPC Class Codes: G06F 1/3209 Monitoring remote activity, e.g. over telephone lines or network connections
• CPC Class Codes: G06F 13/42 Bus transfer protocol, e.g. handshake; Synchronisation

Abstract

A power state broadcast mechanism. A master device may broadcast a message through the use of a protocol to each of one or more slave devices to inform the slave devices of the power state of a computer system. The broadcast message may include a protocol header indicating the start of the broadcast transaction, a function type parameter indicating the type of broadcast transaction, and power state data indicating the power state of the computer system. Each of the slave devices may read the protocol header to detect the start of a broadcast transaction, and the function type parameter to determine the type of broadcast transaction. If the function type parameter indicates a power state broadcast transaction, each of the slave devices may read the power state data included in the broadcast message and determine whether to adjust the current power state of the slave device.

Claims

1. A computer system comprising:

a plurality of slave devices;

a master device configured to broadcast a message to each of the plurality of slave devices to inform the plurality of slave devices of a power state of the computer system;

wherein the master device is configured to broadcast the message through the use of a protocol;

wherein the broadcast message includes at least power state data indicating the power state of the computer system; and

wherein each of the plurality of slave devices is configured to read the power state data included in the broadcast message and determine whether to adjust a current power state of the slave device based on the power state data and one or more of;

current activity trends

historical information of activity trends;

currently executing transactions;

pending transactions;

or

amount of processing power being used.

2. The computer system of claim 1, wherein the broadcast message further includes a protocol header indicating the start of a broadcast transaction.

3. The computer system of claim 1, wherein the broadcast message further includes a protocol header indicating the start of a broadcast transaction, and a function type parameter indicating the type of broadcast transaction.

4. The computer system of claim 3, wherein each of the plurality of slave devices is configured to read the protocol header included in the broadcast message to detect the start of a broadcast transaction, and the function type parameter included in the broadcast message to determine the type of broadcast transaction, wherein in response to reading the function type parameter indicating a power state broadcast transaction each of the plurality of slave devices is configured to read the power state data included in the broadcast message and determine whether to adjust the current power state of the slave device.

5. The computer system of claim 1, wherein the master device is configured to broadcast the message through the use of a bus protocol.

6. The computer system of claim 1, wherein the master device is configured to broadcast the message through the use of a wireless protocol.

7. The computer system of claim 1, wherein, if the power state data included in the broadcast message indicates that the computer system is in a reduced power mode, each of the plurality of slave devices is configured to determine whether to change its current power state to a reduced power mode.

8. The computer system of claim 1, wherein, if the power state data included in the broadcast message indicates that the computer system is in a normal power mode, each of the plurality of slave devices is configured to determine whether to change its current power state to a normal power mode.

9. The computer system of claim 1, wherein the master device is configured to broadcast the message to each of the plurality of slave devices through a single bus line.

10. The computer system of claim 1, wherein the master device is configured to broadcast the message to each of the plurality of slave devices through two or more bus lines.

11. The computer system of claim 1, wherein each of the plurality of slave devices is configured to determine the power state of the computer system without the use of one or more dedicated power pins for receiving power state signals.

12. A method for managing power in a computer system, the method comprising:

broadcasting a message through the use of a protocol to each of a plurality of slave devices comprised in the computer system to inform the plurality of slave devices of a power state of the computer system, wherein the broadcast message includes at least power state data indicating the power state of the computer system;

each of the plurality of slave devices reading the power state data included in the broadcast message; and

each of the plurality of slave devices determining whether to adjust its current power state based on the power state data and one or more of;

current activity trends;

historical information of activity trends;

currently executing transactions;

pending transactions;

or

amount of processing power being used.

13. The method of claim 12, further comprising each of the plurality of slave devices reading the protocol header included in the broadcast message to detect the start of a broadcast transaction.

14. The method of claim 13, further comprising, each of the plurality of slave devices reading the function type parameter included in the broadcast message to determine the type of broadcast transaction, wherein, in response to reading the function type parameter indicating a power state broadcast transaction, each of the plurality of slave devices reading the power state data included in the broadcast message, and determining whether to adjust its current power state.

15. The method of claim 12, further comprising broadcasting the message through the use of a bus protocol.

16. The method of claim 12, further comprising broadcasting the message through the use of a wireless protocol.

17. The method of claim 12, further comprising broadcasting the message to each of the plurality of slave devices through a single wire bus line.

18. The method of claim 12, further comprising broadcasting the message to each of the plurality of slave devices through a bus line comprising two or more wires.

19. A slave device comprised in a computer system and configured to receive a message broadcast from a master device comprised in the computer system to inform the slave device of a power state of the computer system, wherein the master device is configured to broadcast the message through the use of a bus protocol, wherein the broadcast message includes at least power state data indicating the power state of the computer system, wherein the slave device is configured to read the power state data included in the broadcast message and determine whether to adjust a current power state of the slave device based on other factors when the power state data indicates that the power state of the computer system is the same as the current power state of the slave device.

20. A master device comprised in a computer system and configured to broadcast a message to a plurality of slave devices comprised in the computer system to inform the slave devices of a power state of the computer system, wherein the master device is configured to broadcast the message through the use of a bus protocol, wherein the broadcast message includes at least power state data indicating the power state of the computer system, wherein each of the plurality of slave devices is configured to read the power state data included in the broadcast message and determine whether to adjust a current power state of the slave device, and wherein the master device is configured to broadcast the message when a new slave device is connected to the computer system.

21. A motherboard comprising:

a first bus and a second bus a plurality of slave devices coupled to the second bus;

an I/O interface controller configured to interface the first bus to the second bus, and further configured to broadcast a message to each of the plurality of slave devices over the second bus to inform the plurality of slave devices of a power state of a computer system;

wherein the I/O interface controller is configured to broadcast the message through the use of a bus protocol;

wherein the broadcast message includes at least power state data indicating the power state of the computer system; and

wherein each of the plurality of slave devices is configured to read the power state data included in the broadcast message and determine whether to adjust a current power state of the slave device based on the power state data.