Hello,
We are seeing errors with the Cisco 9300 10G or 2.5G copper ports (negotiated to 1Gbps) now that we have switched to your DP83867CS PHY. We do not see these errors with our original QCA 8031 PHY that we migrated from.
We see the error behavior change if we put different settings into the Viterbi idle threshold register. The best behavior is with that register set to 2. The default of 5 shows the most errors. No setting, however, will avoid these errors.
I pull stats from the following register/fields and see the errors reported:
RXFSTS bit7: SFD_ERR
RECR [15:0]: RXERCNT
STS1 [7:0]: 1000Base-T IDLE ERROR COUNTER
With the idle threshold set to 4:
The idle error counter is not incrementing in the stats. The RXERCNT seems to increment the same as the MAC ethtool rx_crc_errors count and the rx_drop count that is reported by ethtool roughly – just a few packets higher than the sum. The SFD_ERR bit is showing, as well as the BAD_CRC status bit in the same register.
With the idle threshold set to 2:
The idle error counter does not increment in the stats. The RXERCNT seems to increment with the ethtool rx_crc_errors count (no rx_drop counts reported) that is reported by ethtool. The SFD_ERR is NOT showing, but the BAD_CRC status bit is set in the same register.
So it appears the PHY part is detecting these errors we see. The rx_drops seem to follow SFE_ERR being set, and the rx_crc_errors seem to follow the BAD_CRC bit being set, and the frame counts roughly match eth ethtool stats.
Have you had this experience in interoperating with a Cisco 9300 switch? Other switches thus far do not exhibit the issues and the stats are clean. Please advise.
Thanks,
Dave