It potentially looks like this:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/drivers/net/phy/realtek.c?h=v5.10.79&id=bbc4d71d63549bcd003a430de18a72a742d8c91e
I would just try changing the rgmii to rgmii-id to add delays, as its really really rare that no delays need to be added