USB SL811 with SOPC builder

Hello,

I would like to add USB to my Nios2 project. I see everywhere in the forums that the SL811 seems a good choice as USB controller (and it seems it's on the Microtronix board too). Now, is there an SOPC builder USB component that allows me to connect directly to the SL811 chipset ? How do I do to interface the Nios2 and the SL811 ? Is this an IP only available with the Microtronix kit, or can I get it from elsewhere ?

Thanks for help

Regards

Pod