Method and system for communication between a secondary processor and an auxiliary display subsystem of a notebook

• US 20070239920A1
• Filed: 04/05/2006
• Published: 10/11/2007
• Est. Priority Date: 04/05/2006
• Status: Active Grant

• Current Assignee: NVIDIA Corporation
• Original Assignee: PortalPlayer USA, Inc. (NVIDIA Corporation)
• Inventors: Frid, Aleksandr
• Granted Patent: US 8,775,704 B2
• Time in Patent Office: Days
• US Class Current: 710/306
• CPC Class Codes: G06F 1/32 Means for saving power
• CPC Class Codes: G06F 13/00 Interconnection of, or transfer of information or other signals between, memories, input/output devices or central processing units interface circuits for specific input/output devices G06F3/00 ; multiprogram control therefor G06F9/46; multiprocessor systems G06F15/16
• CPC Class Codes: G06F 13/38 Information transfer, e.g. on bus G06F13/14 takes precedence
• CPC Class Codes: G06F 13/4282 on a serial bus, e.g. I2C bus, SPI bus on daisy chain buses G06F13/4247
• CPC Class Codes: G06F 2213/0016 Inter-integrated circuit (I2C)
• CPC Class Codes: G06F 3/14 Digital output to display device ; Cooperation and interconnection of the display device with other functional units
• CPC Class Codes: G06F 3/1438 using more than one graphics controller
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2360/06 Use of more than one graphics processor to process data before displaying to one or more screens
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

A method for communication over an SMB, I2C bus, or other serial bus between an auxiliary display subsystem and a secondary processor of a notebook including the auxiliary display subsystem, and systems, circuits and notebooks configured to perform the method. Typically, communication over the serial bus between the auxiliary display subsystem and secondary processor can occur when the notebook is in a standby or other low-power state (e.g., to obtain system status data or cause the notebook to wake up) or a fully-powered normal operating state. Typically, the auxiliary display subsystem is coupled not only to the notebook'"'"'s secondary processor by the serial bus but also to the notebook'"'"'s central processing unit by another link (e.g., a USB).

Claims

1. A method for communication in a notebook including a secondary processor coupled to a serial bus, and an auxiliary display subsystem, the method including the steps of:

(a) sending at least one message from the auxiliary display subsystem to the secondary processor over the serial bus; and

(b) sending at least one message from the secondary processor to the auxiliary display subsystem over the serial bus.

2. The method of claim 1, wherein steps (a) and (b) are performed while the notebook is in a low-power state.

3. The method of claim 1, wherein step (a) is performed while the notebook is in a low-power state, and the secondary processor, in response to said at least one message from the auxiliary display subsystem, causes the notebook to boot into a fully-powered normal operating state.

4. The method of claim 1, wherein the notebook also includes a central processing unit coupled to the secondary processor, and at least one of the central processing unit and the secondary processor, in response to said at least one message from the auxiliary display subsystem, sends system status data to the auxiliary display subsystem.

5. The method of claim 1, wherein step (b) includes the step of sending system status data from the secondary processor to the auxiliary display subsystem over the serial bus in response to said at least one message from the auxiliary display subsystem.

6. The method of claim 1, wherein step (a) includes the step of sending at least one data request message over the serial bus from the auxiliary display subsystem to the secondary processor while the notebook is in a low-power state, and step (b) includes the step of sending at least one report message over the serial bus from the secondary processor to the auxiliary display subsystem while the notebook is in the low-power state and in response to the at least one data request message.

7. The method of claim 1, wherein the serial bus is a system management bus (SMB), step (a) includes the step of operating a processor of the auxiliary display subsystem as an SMB bus master to send at least one data request message over the SMB to the secondary processor operating as an SMB host controller bus slave while the notebook is in a low-power state, and step (b) includes the step of operating the secondary processor as an SMB host controller bus master to send at least one report message over the SMB to the auxiliary display subsystem while the notebook is in the low-power state and in response to the at least one data request message.

8. The method of claim 1, wherein the serial bus is a system management bus (SMB).

9. The method of claim 8, wherein the secondary processor is configured to operate as an SMB host controller during steps (a) and (b),

step (a) includes the step of operating a processor of the auxiliary display subsystem as an SMB bus master to send at least one data request message to the secondary processor while said secondary processor operates as an SMB host controller bus slave, and

step (b) includes the step of operating the secondary processor as an SMB host controller bus master to send the at least one message to a processor of the auxiliary display subsystem operating as an SMB bus slave.

10. The method of claim 8, wherein the secondary processor is configured to operate as an SMB host controller during steps (a) and (b),

step (a) includes the step of operating a processor of the auxiliary display subsystem as an SMB bus master to send at least one action request message to the secondary processor while said secondary processor operates as an SMB host controller bus slave, and

step (b) includes the step of operating the secondary processor as an SMB host controller bus master to send the at least one message to a processor of the auxiliary display subsystem operating as an SMB bus slave.

11. The method of claim 8, wherein the auxiliary display subsystem includes a processor configured to send the at least one message in accordance with an SMB host notify protocol, the secondary processor is configured to operate as an SMB host controller during steps (a) and (b), and step (a) includes the step of operating the processor of the auxiliary display subsystem as an SMB bus master to send the at least one message to the secondary processor in accordance with the SMB host notify protocol while said secondary processor operates as an SMB host controller bus slave.

12. The method of claim 1, wherein the serial bus is a system management bus (SMB), the notebook includes a universal serial bus (USB), the auxiliary display subsystem is coupled to the SMB and to the USB, and said method also includes the step of:

(c) sending data from the notebook over the USB to the auxiliary display subsystem in response to a data request from said auxiliary display subsystem.

13. The method of claim 12, wherein the auxiliary display subsystem includes memory and said method also includes the step of:

(d) caching in the memory at least some of the data sent to the auxiliary display subsystem over the USB during step (c).

14. The method of claim 1, wherein the notebook includes a universal serial bus (USB), the auxiliary display subsystem is coupled to the serial bus and the USB, and said method also includes the step of:

(c) sending data from the notebook over the USB to the auxiliary display subsystem in response to a data request from said auxiliary display subsystem.

15. The method of claim 14, wherein the auxiliary display subsystem includes memory, and said method also includes the step of:

(d) caching in the memory at least some of the data sent to the auxiliary display subsystem over the USB during step (c).

16. The method of claim 1, wherein the notebook also includes a central processing unit, the notebook includes a universal serial bus (USB), the auxiliary display subsystem is coupled to the serial bus and the USB, the central processing unit is coupled to the USB, step (a) includes the step of sending at least one action request from the auxiliary display subsystem while the notebook is in a low-power state to cause the secondary processor to cause the notebook to boot into a fully-powered normal operating state, and said method also includes the step of:

(c) when the notebook is in the fully-powered normal operating state, sending at least one message from the auxiliary display subsystem over the USB to the central processing unit to cause the notebook to perform at least one operation.

17. The method of claim 16, wherein step (c) includes the step of sending at least one data request from the auxiliary display subsystem over the USB to the central processing unit, and wherein said method also includes the step of:

(d) sending at least one of audio data, video data, and image data over the USB to the auxiliary display subsystem in response to the at least one data request.

18. A notebook, including:

a serial bus;

a secondary processor coupled to the serial bus; and

an auxiliary display subsystem coupled to the serial bus, wherein the auxiliary display subsystem is configured to send at least one message to the secondary processor over the serial bus, and the secondary processor is configured to send at least one message to the auxiliary display subsystem over the serial bus.

19. The notebook of claim 18, wherein the secondary processor is an embedded controller configured to perform keyboard controller functions, and said notebook also includes:

a central processing unit coupled to the embedded controller.

20. The notebook of claim 18, wherein the auxiliary display subsystem is configured to send the at least one message to the secondary processor over the serial bus while the notebook is in a low-power state, and the secondary processor is configured to send the at least one message to the auxiliary display subsystem over the serial bus while the notebook is in the low-power state.

21. The notebook of claim 18, wherein the notebook also includes a central processing unit coupled to the secondary processor, and at least one of the central processing unit and the secondary processor is configured to send system status data to the auxiliary display subsystem in response to at least one said message from the auxiliary display subsystem.

22. The notebook of claim 18, wherein the secondary processor is configured to send system status data to the auxiliary display subsystem in response to at least one said message from the auxiliary display subsystem.

23. The notebook of claim 18, wherein the auxiliary display subsystem is configured to send at least one data request message over the serial bus to the secondary processor while the notebook is in a low-power state, and the secondary processor is configured to send at least one report message over the serial bus to the auxiliary display subsystem in response to the at least one data request message while the notebook is in the low-power state.

24. The notebook of claim 18, wherein the serial bus is a system management bus (SMB), the auxiliary display subsystem includes a processor coupled to the SMB, the processor of the auxiliary display subsystem is configured to operate as an SMB bus master to send at least one data request message over the SMB to the secondary processor while said secondary processor operates as an SMB host controller bus slave and the notebook is in a low-power state.

25. The notebook of claim 18, wherein the serial bus is a system management bus (SMB).

26. The notebook of claim 25, wherein the auxiliary display subsystem includes a processor coupled to the SMB, the secondary processor is configured to operate as an SMB host controller, the processor of the auxiliary display subsystem is configured to operate as an SMB bus master to send at least one data request message over the SMB to the secondary processor while said secondary processor operates as the SMB host controller bus slave, and the secondary processor is configured to operate as an SMB host controller bus master to send the at least one message to the processor of the auxiliary display subsystem while said processor of the auxiliary display subsystem operates as an SMB bus slave.

27. The notebook of claim 25, wherein the auxiliary display subsystem includes a processor coupled to the SMB, the secondary processor is configured to operate as an SMB host controller, the processor of the auxiliary display subsystem is configured to operate as an SMB bus master to send at least one action request message over the SMB to the secondary processor while said secondary processor operates as the SMB host controller bus slave, and the secondary processor is configured to operate as an SMB host controller bus master to send the at least one message to the processor of the auxiliary display subsystem while said processor of the auxiliary display subsystem operates as an SMB bus slave.

28. The notebook of claim 25, wherein the auxiliary display subsystem includes a processor configured to send the at least one message over the SMB in accordance with an SMB host notify protocol, and the secondary processor is configured to operate as an SMB host controller bus slave to receive the at least one message from the processor of the auxiliary display subsystem.

29. The notebook of claim 18, wherein the serial bus is a system management bus (SMB), the notebook includes a universal serial bus (USB), the auxiliary display subsystem is coupled to the SMB and to the USB, and the auxiliary display subsystem is configured to receive data sent thereto over the USB in response to a data request from said auxiliary display subsystem.

30. The notebook of claim 29, wherein the auxiliary display subsystem includes memory and is configured to cache in the memory at least some of the data sent thereto over the USB.

31. The notebook of claim 18, wherein the notebook includes a universal serial bus (USB), the auxiliary display subsystem is coupled to the serial bus and to the USB, and the auxiliary display subsystem is configured to receive data sent thereto over the USB in response to a data request from said auxiliary display subsystem.

32. The notebook of claim 31, wherein the auxiliary display subsystem includes memory and is configured to cache in the memory at least some of the data sent thereto over the USB.

33. The notebook of claim 18, wherein the notebook also includes:

a universal serial bus (USB);

a central processing unit coupled to the USB; and

wherein the auxiliary display subsystem is coupled to the serial bus and to the USB, the auxiliary display subsystem is configured to send at least one action request over the serial bus while the notebook is in a low-power state to cause the notebook to boot into a fully-powered normal operating state, and the auxiliary display subsystem is configured to send at least one action request to the central processing unit over the USB when the notebook is in the fully-powered normal operating state to cause the notebook to perform at least one operation.

34. The notebook of claim 33, wherein the auxiliary display subsystem is configured to send at least one data request to the central processing unit over the USB, and the central processing unit is configured to cause at least one of audio data, video data, and image data to be sent over the USB to the auxiliary display subsystem in response to the at least one data request.

35. An auxiliary display subsystem for use in a notebook including a secondary processor coupled to a serial bus and a chipset coupled to a second bus, said auxiliary display subsystem including:

a first interface configured to be coupled to the serial bus;

a second interface configured to be coupled to the second bus; and

a processor coupled to the first interface and to the second interface, and configured to assert at least one message to the first interface and at least one other message to the second interface.

36. The auxiliary display subsystem of claim 35, wherein the processor is configured to assert at least one data request message to the first interface and to receive at least one report message that is asserted to the first interface in response to the at least one data request message.

37. The auxiliary display subsystem of claim 35, wherein the serial bus is a system management bus (SMB) and the processor is configured to operate as an SMB bus master to assert at least one data request message to the first interface.

38. The auxiliary display subsystem of claim 35, wherein the serial bus is a system management bus (SMB) and the processor is configured to operate as an SMB bus master to assert at least one action request message to the first interface.

39. The auxiliary display subsystem of claim 35, wherein the serial bus is a system management bus (SMB) and the processor is configured to assert the at least one message to the first interface in accordance with an SMB host notify protocol.

40. The auxiliary display subsystem of claim 35, wherein the serial bus is a system management bus (SMB), the second bus is a universal serial bus (USB), and the processor is configured to receive data received at the second interface in response to a data request asserted at the first interface.

41. The auxiliary display subsystem of claim 40, wherein the auxiliary display subsystem includes memory and the processor is configured to cache in the memory at least some of the data received at the second interface.

42. The auxiliary display subsystem of claim 35, wherein the processor is configured to receive data received at the second interface in response to a data request asserted at the first interface.

43. The auxiliary display subsystem of claim 42, wherein the auxiliary display subsystem includes memory and the processor is configured to cache in the memory at least some of the data received at the second interface.