Hi @myehiash ,
For current status, we just can connect to PHY through pin strapping for S32K388 board



After that, PHY is in RGMII, 1Gbps.
To configure MDC, you just need to configure pin MDC as output. Clock provided from GMAC through this pin.
For the function Eth_43_GMAC_ReadMmd to support PHY transceiver support clause 45. You can read this information in PHY datasheet, like:


Description of parameters:
- CtrlIdx: ETH controller index
- TrcvIdx: PHY transceiver's address.
- Mmd: 1 (MMD1), 3 (MMD3), 30 (MMD30)
- RegAddress: address of register that you want to write or read. You can read this value in datasheet.
- *RegValPtr : store value read from PHY.
Best regards,
Nhi