diff options
Diffstat (limited to 'Documentation/x86/pat.txt')
| -rw-r--r-- | Documentation/x86/pat.txt | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/Documentation/x86/pat.txt b/Documentation/x86/pat.txt index db0de6cfc3515..54944c71b819b 100644 --- a/Documentation/x86/pat.txt +++ b/Documentation/x86/pat.txt @@ -48,6 +48,9 @@ set_memory_uc | UC- | -- | -- | set_memory_wc | WC | -- | -- | set_memory_wb | | | | | | | | +set_memory_wt | WT | -- | -- | + set_memory_wb | | | | + | | | | pci sysfs resource | -- | -- | UC- | | | | | pci sysfs resource_wc | -- | -- | WC | @@ -150,8 +153,8 @@ can be more restrictive, in case of any existing aliasing for that address. For example: If there is an existing uncached mapping, a new ioremap_wc can return uncached mapping in place of write-combine requested. -set_memory_[uc|wc] and set_memory_wb should be used in pairs, where driver will -first make a region uc or wc and switch it back to wb after use. +set_memory_[uc|wc|wt] and set_memory_wb should be used in pairs, where driver +will first make a region uc, wc or wt and switch it back to wb after use. Over time writes to /proc/mtrr will be deprecated in favor of using PAT based interfaces. Users writing to /proc/mtrr are suggested to use above interfaces. @@ -159,7 +162,7 @@ interfaces. Users writing to /proc/mtrr are suggested to use above interfaces. Drivers should use ioremap_[uc|wc] to access PCI BARs with [uc|wc] access types. -Drivers should use set_memory_[uc|wc] to set access type for RAM ranges. +Drivers should use set_memory_[uc|wc|wt] to set access type for RAM ranges. PAT debugging |