Visible to Intel only — GUID: max1687435967469
Ixiasoft
Visible to Intel only — GUID: max1687435967469
Ixiasoft
4.6. Auto-Negotation and Link Training
E-Tile Auto Negotiation and Link Training
When you enable the AN/LT feature in the IP GUI, the AN/LT logic, which includes the AN/LT CSR and CPU, is instantiated in the E-Tile Ethernet IP.
F-Tile Auto-Negotiation and Link Training
Unlike previous AN/LT blocks, such as Stratix 10 and older, this block is not dependent on the main or base Ethernet IP. That is, the AN/LT block is a distinct and independent IP from the basic Ethernet address. The Ethernet Subsystem IP automatically connects the AN/LT IP to the base Ethernet IP.
The number of AN/LT IP instantiated in the Ethernet Subsystem IP depends on the different Ethernet configurations configured in the Ethernet Subsystem IP. With the same configuration, one AN/LT IP can be connected to multiple Ethernet ports.
AN/LT IP can be enabled with dynamic reconfiguration, and only once instance of the IP is required per dynamic reconfiguration group. When you enable AN/LT IP in the DR group, the AN/LT IP is instantiated and connected to the Ethernet Subsystem Base IP. AXI-Lite provides you the access to control and status monitoring.
- After power on, wait for the auto-negotiation process to complete. The auto-negotiation completion can be monitored using the port X status register bit 29, which is per port register.
- Once AN is complete, please check AN results and based on that, you can decide on the dynamic reconfiguration profile (You can skip dynamic reconfiguration if the auto-negotiation results match the startup profile).
- Once dynamic reconfiguration is complete, write 1 to the AN/LT configuration register bit 16, 'Continue AN Flow', with address (Offset + 0x314) to unpause the AN/LT IP.
Note:
- keep unused ports in reset, as multiport dynamic reconfiguration is not supported. For example, when dynamically reconfiguring form 100G-4 > 25G, keep ports 1,2, and 3 in reset, while port 0 remains active.
- Before step 3, you must apply a reset before starting dynamic reconfiguration. Once completed, remove the reset. Once completed, remove the reset, but note that the ACK signal does not toggle. (AN/LT applies a reset that remains in place, and AN/LT removes it during LT).