Please refer to the following update from the AE team.
Can you please share the u-boot commands used to read registers from both PHYs?
Since they are on the same bus, they should show the same Clause implementation if they are both CL45 devices.
In u-boot, if you give two arguments, it will try CL22. If you give three arguments, it will try CL45.
At the HW level, you can double check MDIO_CCFG[ENC45]=1 from the MDIO offsets.
the offsets-
;MAC1 @ e_0000
;MDIO-1 @ e_1000
;MAC2 @ e_2000
;MDIO-2 @ e_3000
;MAC3 @ e_4000
;MDIO-3 @ e_5000
;MAC4 @ e_6000
;MDIO-4 @ e_7000
;MAC5 @ e_8000
;MDIO-5 @ e_9000
;MAC6 @ e_a000
;MDIO-6 @ e_b000
;MAC7 @ e_c000
;MDIO-7 @ e_d000
;MAC8 @ e_e000
;MDIO-8 @ e_f000
;MAC9 @ f_0000
;MDIO-9 @ f_1000
;MAC10 @ f_2000
;MDIO-10 @ f_3000
;EMI1 @ f_c000
;EMI2 @ f_d000
I'm also attaching an example TeraTerm macro I shared with another CAS member to read MDIO registers. His case was Linux but you can see the steps and modify Linux memory commands with u-boot memory commands.