Patrick,
The file is modifed to phy.c. Same will be reflected in user guide. The phy.c provide support for generic phy interfaces. The custom changes if required for any specific phy have to be incorporated. To configure for the new PHY, changes are required in LwIP port layer (cpswif.c) and the platform (to select PHY mode for port) apart form the changes in device abstraction layer
Regards,
Ramesh D