Aaron,
I see you have the code to setup the I2C interrupt which has nothing to do with SYS/BIOS but to get it to fire and be handled, you need to register it with the kernel Hwi dispatcher. In your cfg file, you can create a Hwi Instance by giving it the interrupt number of that I2C peripheral and registering your ISR function that will run every time there is an interrupt. I can walk you through how to do this.
What do you think?
Moses