Auto Negotiation

The ethernet model supports autonegotiation for transfer speed capabilities.

The process is based on issuing an auto-negotiation request to the ethernet link model. The link will then issue autonegotiationg requests to each attached PHY, and finally call autonegotiateDone for all attached PHYs.

Each PHY will be called with the current known capabilities. It should return the same capabilities with potentially some of them cleared.

The actual final capabilities are reported with autonegotiateDone.

There, a PHY will select the highest priority common mode. Which by the standard is:

  1. 40GBASE T FD

  2. 25GBASE T FD

  3. 10GBASE T FD

  4. 5GBASE T FD

  5. 2.5GBASE T FD

  6. 1000BASE T FD

  7. 1000BASE T HD

  8. 100BASE T2 FD

  9. 100BASE TX FD

  10. 100BASE T2 HD

  11. 100BASE T4

  12. 100BASE TX HD

  13. 10BASE T FD

  14. 10BASE T HD

Note that TEMU does not support emulation of 2.5 GBASE and above at this moment.