SGI has no plan to release the sort of low-level info in question. There has never been any plan to make Irix open-source, and the drivers for Irix won't be open-sourced either. This issue has been discussed several years ago, including the licensing of Irix source, but SGI decided to not do that.so we're out of luck for the time being.
Doh! I know that IRIX can't easily be open sourced because pieces are licensed. But it's a shame they won't open the drivers, or at least technical documentation.
- Ethan