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author | venkatesh.pallipadi@intel.com <venkatesh.pallipadi@intel.com> | 2008-03-19 00:00:14 (GMT) |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2008-04-17 15:41:19 (GMT) |
commit | 2e5d9c857d4e6c9e7b7d8c8c86a68a7842d213d6 (patch) | |
tree | 6c90c0f9f38ff85e2f42ddc0f4ef0291cdd47d38 /include/asm-x86/mtrr.h | |
parent | d27554d874c7eeb14c8bfecdc39c3a8618cd8d32 (diff) | |
download | linux-2e5d9c857d4e6c9e7b7d8c8c86a68a7842d213d6.tar.xz |
x86: PAT infrastructure patch
Sets up pat_init() infrastructure.
PAT MSR has following setting.
PAT
|PCD
||PWT
|||
000 WB _PAGE_CACHE_WB
001 WC _PAGE_CACHE_WC
010 UC- _PAGE_CACHE_UC_MINUS
011 UC _PAGE_CACHE_UC
We are effectively changing WT from boot time setting to WC.
UC_MINUS is used to provide backward compatibility to existing /dev/mem
users(X).
reserve_memtype and free_memtype are new interfaces for maintaining alias-free
mapping. It is currently implemented in a simple way with a linked list and
not optimized. reserve and free tracks the effective memory type, as a result
of PAT and MTRR setting rather than what is actually requested in PAT.
pat_init piggy backs on mtrr_init as the rules for setting both pat and mtrr
are same.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'include/asm-x86/mtrr.h')
-rw-r--r-- | include/asm-x86/mtrr.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/asm-x86/mtrr.h b/include/asm-x86/mtrr.h index 319d065..968794a 100644 --- a/include/asm-x86/mtrr.h +++ b/include/asm-x86/mtrr.h @@ -84,6 +84,8 @@ struct mtrr_gentry #ifdef __KERNEL__ +extern u8 mtrr_type_lookup(u64 addr, u64 end); + /* The following functions are for use by other drivers */ # ifdef CONFIG_MTRR extern void mtrr_save_fixed_ranges(void *); |