Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/STMicroelectronics/STM32H7x5_CM7/Ethernet_MAC/MACMDIOAR#0x0
MDIO address register
MB
C45E
GOC
SKAP
CR
NTC
RDA
PA
BTB
PSE
https://github.com/cmsis-svd/cmsis-svd-data