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
