Agilex mdio bus in kernel-5.15.70

I’ve migrated our code base from kernel 5.10.90 to 5.15.70. The kernel boots fine and most of the devices are getting detected except for the MDIO bus. The MDIO bus seems to be reading 0xffff no matter what I do. This bus works fine in the uboot as well as in kernel 5.10.90.

On comparing the logs there seems to be a difference in the way libphy is works and the FIXED mdio bus is probed.

The left of the snapshots is kernel-5.10.90 and the right is kernel-5.15.70. As you can see in the below snippets libphy does not get called in 5.15.

Libphy gets stmmac in 5.10:
libphy:stmmac: probed

In 5.15 kernel, we do not see this message.

Libphy sees the marvell switch in 5.10:
libphy:mv88e6xxx SMI: probed

In 5.15, the mdio bus reads 0xffff

We are using gmac1 instead of gmac0.
I tried loading the 5.15.70 kernel with its dts on the Agilex devkit(Enpirion). The stmmac seems to detect the phy, but libphy messages are not there.

Can you please help to figure out what am I missing here?

Thanks and Regards,