f9 iommu

[Wolfgang S. Rupprecht]

I'm trying to bring up F9 on an Asus M3A78-T (a relatively new AMD
Phenom-x4 capable board).  Going through /var/log/messages I see that
the kernel doesn't think the BIOS enabled the IOMMU and gripes about
it.

Googleing a bit found me a magic parameter to add to grub.conf,
"iommu=memaper=4".  That gets me a new error message preceding the
former: "kernel: Aperture pointing to e820 RAM. Ignoring.".  I do have
over 4g of dram, so having a bounce-buffer sounds important, but I'm
plumb out of ideas.  Is there a slower fallback the kernel is using
(like purely software moves???) for systems that don't have a working
IOMMU?

-wolfgang
-- 
Wolfgang S. Rupprecht              http://www.full-steam.org/  (ipv6-only)
         You may need to config 6to4 to see the above pages.