Running leJOS on the Raspberry Pi as a Linux host is straightforward.
What I want to do is use the RPi as a greatly enhanced Lego NXT running leJOS.
To do this I have added an Arduino Uno and a nxshield-D, and some Lipo batteries and charger and a voltage regulator.
The RPi talks to the Arduino by i2c, which in turn uses i2c to talk to the nxshield.
This allows the RPi to drive all Lego NXT peripherals.
There is no firmware as the RPi runs an OpenJDK JVM.
A modified classes.jar is used.
This project is currently on hold waiting for another RPi from RS Components.