Besides MDIO, can you confirm that programming routines can be executed through I2C, UART, and/or SPI?
As outlined already in the thread
for now only the MDIO is supported on ADuCM320.
The part that is released at the moment has a bootloader that can take data over MDIO and program the flash. There are plans to release a different model for ADUCM320 (ADuCM320i) which will have an I2C bootloader.
However there is nothing to stop the you from writing an application that can take data over any serial port and program it down on the flash. You would then be free to have your own protocol.
Retrieving data ...