x86, pat: New i/f for driver to request memtype for IO regions
Add new routines to request memtype for IO regions. This will currently
be a backend for io_mapping_* routines. But, it can also be made available
to drivers directly in future, in case it is needed.
reserve interface reserves the memory, makes sure we have a compatible
memory type available and keeps the identity map in sync when needed.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/arch/x86/include/asm/pat.h b/arch/x86/include/asm/pat.h
index 7af14e5..e2c1668 100644
--- a/arch/x86/include/asm/pat.h
+++ b/arch/x86/include/asm/pat.h
@@ -19,4 +19,9 @@
extern int kernel_map_sync_memtype(u64 base, unsigned long size,
unsigned long flag);
+int io_reserve_memtype(resource_size_t start, resource_size_t end,
+ unsigned long *type);
+
+void io_free_memtype(resource_size_t start, resource_size_t end);
+
#endif /* _ASM_X86_PAT_H */