General input/output architecture, protocol and related methods to manage data integrity

• US 7,152,128 B2
• Filed: 08/23/2002
• Issued: 12/19/2006
• Est. Priority Date: 08/24/2001
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Creta, Ken, Fanning, Blaise, Ajanovic, Jasmin, Harriman, David, Moore, Wayne, Lee, David M., Wehage, Eric R., Gremel, Buck
• Primary Examiner(s): Myers, Paul R.
• Application Number:
  US10/227,600
• Publication Number:
  US 20030145134A1
• Time in Patent Office: 1,579 Days
• Field of Search: 714/4, 714/758, 714/746, 710/100, 710/305
• US Class Current: 710/305
• CPC Class Codes: G06F 13/124 where hardware is a sequential transfer control unit, e.g. microprocessor, peripheral processor or state-machine
• CPC Class Codes: G06F 13/385 for adaptation of a particular data processing system to different peripheral devices
• CPC Class Codes: G06F 13/4059 where the synchronisation uses buffers, e.g. for speed matching between buses
• CPC Class Codes: G06F 13/42 Bus transfer protocol, e.g. handshake; Synchronisation
• CPC Class Codes: G06F 13/4221 being an input/output bus, e.g. ISA bus, EISA bus, PCI bus, SCSI bus
• CPC Class Codes: G06F 13/4252 using a handshaking protocol
• CPC Class Codes: G06F 13/4265 on a point to point bus G06F13/4247, G06F13/4282 take precedence
• CPC Class Codes: G06F 13/4269 using a handshaking protocol, e.g. Centronics connection
• 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 5/06 for changing the speed of data flow, i.e. speed regularising or timing, e.g. delay lines, FIFO buffers; over- or underrun control therefor G06F7/78 takes precedence
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/30 in combination with information about buffer occupancy at either end or at transit nodes

Abstract

An enhanced general input/output communication architecture, protocol and related methods are presented. In one embodiment, a method is described comprising receiving a datagram at general input/output (GIO) interface from a remote GIO interface coupled through a GIO link, validating content of one or more packets embedded within the received datagram, and issuing an acknowledgment to the remote GIO interface that the datagram was successfully received on positive validation of the datagram before promoting the embedded packets to a transaction layer of the GIO interface. Other embodiments are also described.

Claims

1. A method comprising:

receiving a datagram at general input/output (GIO) interface from a remote GIO interface coupled through a GIO link, wherein the GIO interface is implemented on a communication port implementing a communication stack including a transaction layer, a data link layer, and a physical layer, the physical layer to receive the datagram;

validating content of one or more packets embedded within the received datagram by determining whether the one or more packets meet predetermined framing requirements, the validating performed by each of the physical link layer and the data link layer of the GIO interface;

if the framing requirements are met, stripping framing boundaries from the datagram to reveal one or more data link layer packets; and

on positive validation of the datagram, issuing an acknowledgment to the remote GIO interface that the datagram was successfully received before promoting the embedded data link layer packets to a transaction layer of the GIO interface, wherein the acknowledgement includes flow control update information to be transmitted to the GIO interface.

2. A method according to claim 1, the element of validating comprising confirming by the physical link layer that the datagram was received at the physical link layer from the GIO link without error.

3. A method according to claim 2, the element of validating further comprising the data link layer:

identifying a sequence number associated with the received datagram; and

confirming that an accurate sequence number is associated with the received datagram based, at least in part, on a last sequence number employed in communication between the interface(s).

4. A method according to claim 3, the element of validating further comprising the data link layer:

identifying an indication of content integrity within the received datagram;

independently calculating an indication of content integrity based, at least in part, on the content of the datagram; and

confirming that the identified indication matches that of the calculated indication.

5. A method according to claim 4, wherein the indication of content integrity is a cyclical redundancy check (CRC) value.

6. A method according to claim 2, the element of validating further comprising the data link layer:

identifying an indication of content integrity within the received datagram;

independently calculating an indication of content integrity based, at least in part, on the content of the received datagram; and

confirming that the identified indication matches that of the calculated indication.

7. A method according to claim 6, wherein the indication of content integrity is a hash of at least a subset of content of the datagram.

8. A method according to claim 1, the element of validating comprising the data link layer:

identifying an indication of payload integrity within the received datagram;

independently calculating the indication of payload integrity based, at least in part, on the payload of the datagram; and

confirming that the identified indication matches that of the calculated indication.

9. A method according to claim 1, the element of validating comprising the data link layer:

identifying a sequence number associated with the received datagram; and

confirming that an accurate sequence number is associated with the received datagram based, at least in part, on a last sequence number employed in communication between the interface(s).

10. A method according to claim 1, the element of issuing an acknowledgement comprising:

issuing a positive acknowledgement if the datagram is validated.

11. A method according to claim 1, the element of issuing an acknowledgement comprising:

issuing a negative acknowledgement if the datagram fails to validation.

12. A method according to claim 11, the element of issuing a negative acknowledgement further comprising:

maintaining a count of successive negative acknowledgements; and

reinitialize the GIO link between the GIO interface and the remote GIO interface.

13. A method according to claim 1, further comprising:

promoting by the data link layer a validated packet to a transaction layer of the GIO interface.

14. A general input/output (GIO) interface comprising:

a physical layer, to couple the GIO interface to a GIO communication link; and

a data link layer, coupled with the physical layer, to;

receive a datagram from a remote GIO interface through the GIO communication link, wherein the GIO interface is implemented on a communication port implementing a communication stack including a transaction layer, a data link layer, and a physical layer, the physical layer to receive the datagram;

validate content of one or more packets embedded within the received datagram by determining whether the one or more packets meet predetermined framing requirements, the validating performed by each of the physical link layer and the data link layer of the GIO interface;

if the framing requirements are met, strip framing boundaries from the datagram to reveal one or more data link layer packets; and

issue an acknowledgement to the remote GIO interface that the datagram was successfully received based, at least in part, on a result of the validation; and

a transaction layer, coupled with the data link layer, to provide flow control update information to be transmitted to the remote GIO interface with the acknowledgement.

15. A GIO interface according to claim 14, wherein the data link layer receives an indication from the physical layer that the datagram was received from the GIO link without error.

16. A GIO interface according to claim 15, wherein the data link layer identifies a sequence number associated with the received datagram, and confirms that an accurate sequence number is associated with the received datagram based, at least in part, on a last sequence number employed in communication between the interface(s) to validate the received datagram.

17. A GIO interface according to claim 16, wherein the data link layer identifies an indication of payload integrity within the received datagram, calculates another version of the indication based, at least in part, on the payload of the datagram, and confirms that the identified indication matches the calculated indication to validate content of the received datagram.

18. A GIO interface according to claim 17, wherein the data link layer promotes content of the received datagram to a coupled transaction layer of the GIO interface upon validation of the content of the received datagram.

19. A GIO interface according to claim 17, wherein the data link layer issues a negative acknowledgement if the content of the received datagram fails validation.

20. A GIO interface according to claim 19, wherein the data link layer initiates reinitialization of the communication link through the physical layer after issuing one or more negative acknowledgements.

21. A GIO interface according to claim 14, wherein the data link layer identifies an indication of payload integrity within the received datagram, calculates another version of the indication based, at least in part, on the payload of the datagram, and confirms that the identified indication matches the calculated indication to validate content of the received datagram.

22. A GIO interface according to claim 21, wherein the indication is a cyclical redundancy check (CRC) value.

23. An electronic component, suitable for use in an electronic device, comprising a GIO interface according to claim 14.

24. An electronic appliance comprising a plurality of electronic components according to claim 23.

25. A storage medium comprising content which, when executed by an accessing device, causes the device to implement a general input/output interface (GIO) with which to communicate with remote GIO interface(s) of other device(s), wherein the GIO interface:

receives a datagram at a general input/output (GIO) interface from a remote GIO interface through a GIO link, wherein the GIO interface is implemented on a communication port implementing a communication stack including a transaction layer, a data link layer, and a physical layer, the physical layer to receive the datagram;

validates content of one or more packets embedded within the received datagram by determining whether the one or more packets meet predetermined framing requirements, the validating performed by each of the physical link layer and the data link layer of the GIO interface;

if the framing requirements are met, strips framing boundaries from the datagram to reveal one or more data link layer packets; and

on positive validation of the datagram, issues an acknowledgement to the remote GIO interface that the datagram was successfully received before promoting the embedded data link layer packets to a transaction layer of the GIO interface, wherein the acknowledgement includes flow control update information to be transmitted to the GIO interface.

26. A storage medium according to claim 25, the content to implement the GIO interface further comprising content to confirm by the physical link layer that the datagram was received at the physical link layer of the GIO interface without error incurred during communication over the GIO link.

27. A storage medium according to claim 25, the content to implement the GIO interface further comprising content for the data link layer to:

identify a sequence number associated with the received datagram; and

confirm that an accurate sequence number is associated with the received datagram based, at least in part, on a last sequence number employed in communication between the interface(s).

28. A storage medium according to claim 27, the content to implement the GIO interface further comprising content for the data link layer to:

identify an indication of content integrity within the received datagram;

calculate an independent version of the indication of content integrity based, at least in part, on the content of the datagram; and

confirm that the identified indication matches the calculated indication.

29. A storage medium according to claim 28, the content to implement the GIO interface further comprising content for the data link layer to promote at least a subset of the one or more packets embedded within the received datagram upon identifying an accurate sequence number and positive confirmation of content integrity.

30. A storage medium according to claim 29, the content to implement the GIO interface further comprising content to issue a negative acknowledgement on either detection of an erroneous sequence number or failure to confirm content integrity, or a combination thereof.

31. A storage medium according to claim 30, the content to implement the GIO interface further comprising content to cause the implementing device to reinitialize the GIO link with the remote GIO interface upon issuing one or more negative acknowledgement(s).