AN2433 - LAN9303/LAN9303i SMI Management Mode Programming Guide
The LAN9303 can operate in PHY mode wherein port-0 works as an external PHY to the host (SOC) MAC. While operating in PHY mode, LAN9303 can be either SMI-managed or I2C-managed.
This document briefly explains LAN9303 SMI management mode and how to access LAN9303 registers. All the code samples and explanations are made with respect to the Linux Operating System.