Method and system for configuring fibre channel ports

• US 7,558,281 B2
• Filed: 07/20/2004
• Issued: 07/07/2009
• Est. Priority Date: 07/21/2003
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: QLogic Corporation (Marvell Technology Group Limited)
• Inventors: Dropps, Frank R., Papenfuss, Gary M., Kohlwey, Ernest G.
• Primary Examiner(s): Harper; Kevin C
• Assistant Examiner(s): WONG, XAVIER S
• Application Number:
  US10/894,917
• Publication Number:
  US 20050018650A1
• Time in Patent Office: 1,813 Days
• Field of Search: 370/238, 370/351, 370/352, 370/357, 370360-366, 370/389, 370/392, 370/400, 370/410, 370/412, 370/413, 370/419, 370/420, 370/428, 370/437, 370/461, 370/463, 370/537, 370229-231, 370/251, 370/421, 370/422, 709/886, 709/238, 709/233, 709/249
• US Class Current: 370/422
• CPC Class Codes: G06F 13/385 for adaptation of a particular data processing system to different peripheral devices
• CPC Class Codes: H04L 49/101 using crossbar or matrix
• CPC Class Codes: H04L 49/357 Fibre channel switches
• CPC Class Codes: H04L 49/65 Re-configuration of fast packet switches

Abstract

A fiber channel switch element for routing fiber channel frame is provided. The switch element includes a fiber channel port that can be configured to support plural data transfer rates. The data transfer rate may be 1 G, 2 G, 4 G, 8 G or 10 G. The switch element includes a clock configuration module for providing a clock signal that is based on the data transfer rate. A receive segment of the fiber channel port sends a signal to a transmit segment to avoid an under flow condition. The receive segment also waits for a certain frame length after a fiber channel frame is written and before the fiber channel frame is read, depending upon a data transfer rate of a source port. Multiple lanes may be configured as a single 10 G multi lane port or as multiple individual ports.

Claims

1. A fibre channel switch element for routing fibre channel frames, comprising:

a fibre channel port that is configured to operate at one or more of a plurality of data transfer rates, wherein a clock rate for one data transfer rate is not an integer multiple of a clock rate for another data transfer rate at which the same fibre channel port is configured to operate;

wherein the same fibre channel port uses one interface to support one or more lanes for receiving and transferring frames at the plurality of data transfer rates; and

the one interface includes a plurality of selectable serial/de-serializer (SERDES), where a higher number of SERDES and a higher number of lanes are selected for a first data transfer rate, and a lower number of SERDES and a lower number of lanes are selected for supporting a second data transfer rate, where the first data transfer rate is higher than the second data transfer rate.

2. The switch element of claim 1, wherein the one data transfer rate is 1 G (gigabit per second).

3. The switch element of claim 1, wherein the one data transfer rate is 2 G (gigabit per second).

4. The switch element of claim 1, wherein the one data transfer rate is 4 G (gigabit per second).

5. The switch element of claim 1, wherein the one data transfer rate is 8 G (gigabit per second).

6. The switch element of claim 1, wherein the one data transfer rate is 10 G (gigabit per second).

7. The switch element of claim 1, wherein the switch element includes a clock configuration module for providing a clock signal that is based on a configured data transfer rate for the same fibre channel port.

8. The switch element of claim 1, wherein when a source port is operating at a lower data transfer rate than a destination port, a receive segment of the fibre channel port sends a signal to a transmit segment to avoid an under flow condition.

9. The switch element of claim 8, wherein the receive segment waits for a certain frame length after a fibre channel frame is written and before the fibre channel frame is read for transmission, where the certain frame length depends upon a data transfer rate of the source port and the destination port.

10. The switch element of claim 1, wherein multiple lanes are configured for the fibre channel port to operate as a single 10 G multi lane port and the same fibre channel port uses the multiple lanes for the same fibre channel port to operate as a different port at a rate lower than 10 G.

11. The switch element of claim 1, wherein same transmit and receive pipelines are used by the same fibre channel port configured to operate at different speeds.

12. The switch element of claim 1, wherein transmit and receive pipelines are selected from a plurality of receive pipelines and transmit pipelines, depending upon a data transfer rate at which the fibre channel port is configured to operate.

13. The switch element of claim 1, wherein a receive buffer for the fibre channel port is shared by multiple lanes, when the fibre channel port is configured to operate at different rates.

14. The switch element of claim 1, wherein a separate receive buffer is used for each of the plurality of lanes when the same fibre channel port is configured to operate at different rates.

15. The switch element of claim 1, wherein each of the plurality of lanes is configured to operate at a different rate depending on the configuration of the fibre channel port.

16. The switch element of claim 1, wherein the fibre channel port auto-negotiates with other ports, the rate at which the configurable fibre channel port is operating.

17. A switch element for routing network frames, comprising:

a port that is configured to operate at one or more of a plurality of data transfer rates;

wherein a clock rate for one data transfer rate is not an even multiple of a clock rate for another data transfer rate at which the port is configured to operate;

wherein the port uses one interface to support one or more lanes for receiving and transferring frames at the plurality of data transfer rates; and

the one interface includes a plurality of selectable serial/de-serializer (SERDES); and

wherein a higher number of SERDES and a higher number of lanes are selected for a first data transfer rate, and a lower number of SERDES and a lower number of lanes are selected for supporting a second data transfer rate, where the first data transfer rate is higher than the second data transfer rate; and

wherein the switch element includes a clock configuration module for providing a clock signal that is based on a configured data transfer rate for the port.

18. The switch element of claim 17, wherein each of the plurality of lanes is configured to operate at a different rate depending on the configuration of the port.

19. The switch element of claim 17, wherein the data transfer rate is one or more of 1 G (gigabit per second);

2 G, 4 G, 8 G, 10 G or higher than 10 G.

20. The switch element of claim 17, wherein the port auto-negotiates with other ports, the rate at which the configurable port is operating.