CVSROOT: /cvs
Module name: src
Changes by: [email protected] 2010/05/08 10:54:08
Modified files:
sys/arch/amd64/amd64: bus_space.c cpu.c pmap.c
sys/arch/amd64/include: pmap.h pte.h
sys/arch/i386/i386: cpu.c machdep.c pmap.c
sys/arch/i386/include: pmap.h pte.h
Log message:
Page Attribute Tables (PAT) support for x86.
PAT allows setting per-mapping cachability bits. Our main interest in it
for write combining mappings so we do not have to rely so heaviliy on
mtrrs (which are stupidly set up on more and more machines). MD flags to
pmap allow setting these bits (which bus_space now uses for PREFETCHABLE
maps), if a vm page has a bit set, then we will use WC for all mappings
of a page (used for userland mappings). We also check for known errata
and fall back to UC- mappings in that case.
comments from kettenis@, tedu@ and will...@. kettenis@, tedu@ ok.
