This appears to be the same issue that was fixed for the Legacy kernel, but not carried forward.   Two fixed are possible - add a "tx-delay" in the DTB or a fix some constants in the Realtek driver.  I've confirmed that the DTB fix corrects the issue.   Add     allwinner,tx-delay-ps = <500>;   to the ethernet device and it works.  Continues to work when soPine is plugged into the baseboard instead of the clusterboard.   Detail on the more comple