Re: pci_mapreg_map(9) and prefetchable BARs

[Jared McNeill <jmcneill%invisible.ca@localhost>]

On Wed, 10 Aug 2011, Michael wrote:
> I don't think there's any MMU out there which could apply anything like 
> this to something smaller than a page. No idea which granularity x86 
> MTRRs allow but it's probably not that small either.

FYI for BUS_SPACE_MAP_PREFETCHABLE on x86 we actually use the Page 
Attribute Table (PAT), not MTRRs.

http://en.wikipedia.org/wiki/Page_Attribute_Table

Cheers,
Jared