Arria 10 GX Development Kit - USXGMII Multi-Rate PHY Not Working

Hi,

I am having issues with the Multi-rate PHY IP with the Arria 10. I am using the Arria 10 GX Development Kit (not the Signal Integrity board). I am attempting to use the PHY in USXGMII mode without success.

I generated all the IP via the "10M/100M/1G/2.5G/5G/10G USXGMII Ethernet Example Design." This creates the Low Latency 10G MAC and the associated 1G/2.5G/5G/10G Multi-rate Ethernet PHY IP.

The pinouts have been updated as expected for the development kit. I'm able to use the System-Console tests to show that traffic is passing between two of the development kits via the SFP+ modules when in 10GBASE-R mode. However, if I switch from 10GBASE-R to USXGMII then I can no longer pass traffic between the boards at speeds lower than 10G. So, 10G works in USXGMII, but the lower speeds 10M, 100M, 1G, 2.5G, and 5G do not. Also, auto-negotiation does not work.

I need this IP to be able to work with RJ45 SFP+ modules. A few different ones have been used and none seem to work (TP-LINK TL-SM5310, 10GTEK ASF-10G2-T, and QINIYEK BJ-SFP-10G-T). The fiber SFP+ modules I have tried do not work whatsoever (won't even establish a link). However, I really need the copper SFP+ modules working.

I have spent quite a bit of time working with this example design and simulating so I'm not sure why USXGMII and USXGMII AN are not working. I'm modifying the 0x400 register via the CSR as expected. This has been done with custom logic and the System-Console. I'm able to read back the changes but it still doesn't allow for traffic flow.

I've narrowed down the issue to either the Multi-rate PHY, the Multi-rate PHY to External PHY inside the SFP+ Communication, or the External PHY inside the SFP+ module. I'm leaning towards a possible SFP+ incompatibility with the multi-rate PHY.

Are there certain SFP+ modules that need to be used for USXGMII to work properly? If so, can you link part numbers? What compatibility should I be looking for with the copper SFP+ modules? I have read that external NBASE-T PHYs should be used, but that does not seem to resolve my issue.

Thank you for your time.