Hi, We are using a Xeon D with an integrated X722 NIC that provides two ports of 8086:37d2 and two ports of 8086:37d0. All four ports show the same behavior: they return a link speed value of 20000 for a 10Gbps link.
This only seems to happen when internally the update_link_reg() function in i40e_ethdev.c is used. This requires the application to use the rte_eth_link_get_nowait() function and not use link status change interrupts. If you use e.g. testpmd with the option --no-lsc-interrupt you can reproduce the behavior since it will suddenly show a link speed of 20000 Mbps instead of 10000 Mbps. Here are two examples of the register values read by update_link_reg(): A 10Gbps link which produces the wrong link speed value: I40E_PRTMAC_LINKSTA: 0x60000080 I40E_PRTMAC_MACC: 0x3d00 A 1Gbps link which produces the correct link speed value: I40E_PRTMAC_LINKSTA: 0x48000081 I40E_PRTMAC_MACC: 0x3d00 Best regards, Martin
