Multiple ethernet ports and port types using a shared data path

1. An interface unit comprising:

a processor configured to execute:

a transmit pipeline configured to transmit egress data, and

a receive pipeline configured to receive ingress data, at least one of the transmit pipeline and the receive pipeline being configured to provide shared resources to a plurality of ports, the shared resources including at least one of: a data path resource and a control logic resource, the shared resources including media access control (MAC) resources at a MAC layer;

wherein a portion of the receive pipeline comprises a plurality of receive pipeline stages that includes link controller processing including local and remote error detection, protocol processing, realignment, frame processing, length processing, header processing, frame check sequence (FCS) verification, layer header extraction, data post-processing, error handling, and interfacing to a physical coding sublayer (PCS); and

wherein a portion of the transmit pipeline comprises a plurality of pipeline stages that includes interfacing to the MAC layer, decoding media independent interface data from the MAC layer, and encoding.

2. The interface unit of claim 1 , wherein the plurality of pipeline stages further includes header insertion, character conversion, and at least one of: auto-negotiation, scrambling including test pattern generation, tag insertion, bit interleaved parity generation, alignment marker insertion, transcoding including parity generation and scrambling, lane steering, and idle randomization including conversion of one or more media independent interface characters into code-groups.

3. The interface unit of claim 2 , wherein the portion of the transmit pipeline that comprises the plurality of pipeline stages includes the auto-negotiation.

4. The interface unit of claim 2 , wherein the portion of the transmit pipeline that comprises the plurality of pipeline stages includes the bit interleaved parity generation.

5. The interface unit of claim 2 , wherein the portion of the transmit pipeline that comprises the plurality of pipeline stages includes the tag insertion.

6. The interface unit of claim 2 , wherein the portion of the transmit pipeline that comprises the plurality of pipeline stages includes the alignment marker insertion.

7. The interface unit of claim 2 , wherein the portion of the transmit pipeline that comprises the plurality of pipeline stages includes the scrambling including test pattern generation.

8. The interface unit of claim 1 , wherein at least one of the transmit pipeline and the receive pipeline are configured to provide shared resources using time division multiplexing.

9. The interface unit of claim 1 , wherein the shared resources include physical coding sublayer (PCS) resources at the PCS.

10. The interface unit of claim 9 , wherein the portion of the transmit pipeline that comprises the plurality of pipeline stages includes at least one of: data request, data buffering, credit management, insertion for physical coding sublayer (PCS) lane marker, length processing, pausing packet generation, pausing packet insertion, media independent interface (MII) signal generation, start of packet (SOP) conversion to a control character, end of packet (EOP) conversion to another control character, frame check sequence (FCS) generation, link layer processing, and interfacing to the physical coding sublayer (PCS).

11. The interface unit of claim 1 , wherein the interface unit further comprises a common media access control (MAC) resource unit.

12. The interface unit of claim 1 , wherein the portion of the receive pipeline that comprises the plurality of receive pipeline stages includes at least one of: decoding, alignment marker locking, skew detection, deskew, reordering, parity checking, alignment marker removal, error rate monitoring, descrambling, test pattern checking, and interfacing to the media access control (MAC) layer.

13. The interface unit of claim 1 , wherein each port of the plurality of ports comprises at least one of: a transmit port wherein the transmit pipeline is further configured to transmit the egress data using the transmit port, and a receive port wherein the receive pipeline is further configured to receive the ingress data using the receive port.

14. The interface unit of claim 1 , wherein ports of the plurality of ports transmit or receive different protocols simultaneously.

15. The interface unit of claim 1 , wherein each pipeline is configured to provide the shared resources to each of some ports, but not all ports, of the plurality of ports.

16. The interface unit of claim 1 , wherein the shared resources include a heartbeat controller that manages credit based flow control to the MAC layer.

17. The interface unit of claim 1 , wherein the portion of the receive pipeline that comprises the plurality of receive pipeline stages includes alignment marker locking.

18. A method comprising:

transmitting egress data through a transmit pipeline;

receiving ingress data through a receive pipeline; and

providing shared resources to a plurality of ports, by at least one of the transmit pipeline and the receive pipeline, the shared resources including at least one of: a data path resource and a control logic resource, the shared resources including media access control (MAC) resources at a MAC layer;

wherein a portion of the receive pipeline comprises a plurality of receive pipeline stages that includes link controller processing including local and remote error detection, protocol processing, realignment, frame processing, length processing, header processing, frame check sequence (FCS) verification, layer header extraction, data post-processing, error handling, and interfacing to a physical coding sublayer (PCS); and

wherein a portion of the transmit pipeline comprises a plurality of pipeline stages that includes interfacing to the MAC layer, decoding media independent interface data from the MAC layer, and encoding.

19. The method of claim 18 , wherein the plurality of pipeline stages further includes header insertion, character conversion, and at least one of: auto-negotiation, scrambling including test pattern generation, tag insertion, bit interleaved parity generation, alignment marker insertion, transcoding including parity generation and scrambling, lane steering, and idle randomization including conversion of one or more media independent interface characters into code-groups.

20. The method of claim 19 , wherein the portion of the transmit pipeline that comprises the plurality of pipeline stages includes the auto-negotiation.

21. The method of claim 19 , wherein the portion of the transmit pipeline that comprises the plurality of pipeline stages includes the alignment marker insertion.

22. The method of claim 19 , wherein the portion of the transmit pipeline that comprises the plurality of pipeline stages includes the tag insertion.

23. The method of claim 19 , wherein the portion of the transmit pipeline that comprises the plurality of pipeline stages includes the bit interleaved parity generation.

24. The method of claim 19 , wherein the portion of the transmit pipeline that comprises the plurality of pipeline stages includes the scrambling including test pattern generation.

25. The method of claim 18 , wherein at least one of the transmit pipeline and the receive pipeline provide shared resources using time division multiplexing.

26. The method of claim 18 , wherein the shared resources include physical coding sublayer (PCS) resources at the PCS.

27. The method of claim 26 , wherein the portion of the transmit pipeline that comprises the plurality of pipeline stages includes at least one of: data request, data buffering, credit management, insertion for physical coding sublayer (PCS) lane marker, length processing, pausing packet generation, pausing packet insertion, media independent interface (MII) signal generation, start of packet (SOP) conversion to a control character, end of packet (EOP) conversion to another control character, frame check sequence (FCS) generation, link layer processing, and interfacing to the physical coding sublayer (PCS).

28. The method of claim 18 , wherein the shared resources further include a common media access control (MAC) resource unit.

29. The method of claim 18 , wherein the portion of the receive pipeline that comprises the plurality of receive pipeline stages includes at least one of: decoding, alignment marker locking, skew detection, deskew, reordering, parity checking, alignment marker removal, error rate monitoring, descrambling, test pattern checking, and interfacing to the media access control (MAC) layer.

30. The method of claim 18 , wherein each port of the plurality of ports comprises at least one of: a transmit port wherein the transmit pipeline transmits the egress data using the transmit port, and a receive port wherein the receive pipeline receives the ingress data using the receive port.

31. The method of claim 18 , wherein ports of the plurality of ports transmit or receive different protocols simultaneously.

32. The method of claim 18 , wherein each pipeline provides the shared resources to each of some ports, but not all ports, of the plurality of ports.