Device-to-device link training
Examples described herein relate to a network interface comprising physical medium dependent (PMD) circuitry, the PMD circuitry to during link training of at least one lane consistent with IEEE 802.3, exit to TIME_OUT state during TRAIN_LOCAL state based on consideration of expiration of a wait timer, loss of local_tf_lock state, and loss of remote_tf_lock state. In some examples, during link training for at least one lane consistent with IEEE 802.3, the PMD circuitry is to exit to TIME_OUT state during TRAIN_REMOTE state based on consideration of expiration of a wait timer, loss of local_tf_lock state, and loss of remote_tf_lock state. In some examples, link training consistent with IEEE 802.3 comprises performance of the PMD control function in Section 162.8.11 of IEEE 802.3ck.
1. A method comprising:
at a first device, during link training of at least one lane consistent with Institute of Electrical and Electronics Engineers (IEEE) 802.3 with a potential link partner, exiting to TIMEOUT state from TRAIN_LOCAL state based on consideration of expiration of a wait timer, loss of local_tf_lock state, and loss of remote_tf_lock state.
2. The method of claim 1 , comprising:
at the first device, during link training for at least one lane consistent with IEEE 802.3, exiting to TIMEOUT state from TRAIN_REMOTE state based on consideration of expiration of a wait timer, loss of local_tf_lock state, and loss of remote_tf_lock state.
3. The method of claim 1 , wherein the link training consistent with IEEE 802.3 comprises performance of a PMD control function in Section 162.8.11 of IEEE 802.3ck.
4. The method of claim 1 , wherein the local_tf_lock state comprises indication of successful decoding of training frames received at the first device from the potential link partner.
5. The method of claim 1 , wherein the remote_tf_lock state comprises indication of successful decoding of training frames from the first device by the potential link partner.
6. The method of claim 1 , comprising restarting link training with a potential link partner after the TIMEOUT state.
7. The method of claim 1 , wherein the first device comprises one or more of a switch, network interface, or server and the potential link partner comprises one or more of a switch, network interface, or server.
8. The method of claim 1 , wherein a connection between the first device and the potential link partner comprises one or more of: a backplane or copper cable.
9. The method of claim 1 , comprising:
at the first device, applying auto-negotiation with the potential link partner before the link training.
10. The method of claim 1 , comprising:
receiving communication of loss of remote_tf_lock state via an out-of-band communication or from a system manager.
11. An apparatus comprising:
physical medium dependent (PMD) circuitry, the PMD circuitry to:
during link training of at least one lane consistent with Institute of Electrical and Electronics Engineers (IEEE) 802.3 with a second device, exit to TIMEOUT state from TRAIN_LOCAL state based on consideration of expiration of a wait timer, loss of local_tf_lock state, and loss of remote_tf_lock state.
12. The apparatus of claim 11 , comprising a physical layer interface (PHY) that comprises the PMD circuitry.
13. The apparatus of claim 11 , comprising a network interface that comprises the PMD circuitry.
14. The apparatus of claim 11 , wherein the PMD circuitry is to:
during link training for at least one lane consistent with IEEE 802.3 with the second device, exit to TIMEOUT state from TRAIN_REMOTE state based on consideration of expiration of a wait timer, loss of local_tf_lock state, and loss of remote_tf_lock state.
15. The apparatus of claim 11 , wherein the link training consistent with IEEE 802.3 comprises performance of a PMD control function in Section 162.8.11 of IEEE 802.3ck.
16. The apparatus of claim 11 , wherein the local_tf_lock state comprises indication of successful decoding of training frames received at the PMD circuitry from the second device.
17. The apparatus of claim 11 , wherein the remote_tf_lock state comprises indication of successful decoding of training frames by the second device.
18. The apparatus of claim 11 , wherein the PMD circuitry is to:
restart link training with the second device after the TIMEOUT state.
19. The apparatus of claim 11 , wherein the PMD circuitry is to:
apply auto-negotiation with the second device before the link training.
20. The apparatus of claim 11 , wherein the PMD circuitry is to:
receive communication of loss of remote_tf_lock state via an out-of-band communication or from a system manager.
21. The apparatus of claim 11 , comprising a server, data center, switch, or rack.