The switch is a 8 + 2-port Gigabit L2 switch with up to 75 Watts of PoE+ power on the 8 Gigabit ports.
2 Uplink ports are SFP cages which support 1000 Base-X mini GBIC modules. Power is supplied via a 54V 1.67A barrel connector.
The UART is broken out to populated header J8:
The secondary UART on the SoC is used to communicate with the microcontroller to manage PoE. The communications are accessible from J9, which is in the microcontroller's power domain. Note that the SoC is in an isolated power domain, so avoid connecting the VCC or GND lines together.
J10 is an SWD header to program the Nuvoton Chip.
Based on the board pictures this device appears to be identical to the D-Link DGS-1210-10P
The switch ships with a bootloader based on Realtek's SDK for RTL83xx SoCs and Linux 2.6.19 based on Realtek's SDK. It has a web interface for all management functions. The board identifies as RTL8380M_INTPHY_2FIB_1G_DEMO (Port Count: 10) for the Realtek SDK.
Since the hardware appears to be identical to the DGS-1210-10P with 256MB of RAM instead of 128MB support with similar features should be a matter of providing a modified DTS file.