https://bugs.freedesktop.org/show_bug.cgi?id=31013
--- Comment #11 from Tom Stellard tstellar@gmail.com 2010-10-23 00:45:06 PDT --- (In reply to comment #9)
r3xx/r4xx actually supports 4 indirections, so if the current code is limiting it to 3, it should be upped to 4. See US_CONFIG.NLEVEL
Isn't the level 3 indirection limited to reading from input registers?