acpi/apei/einj: Add extensions to EINJ from rev 5.0 of acpi spec
ACPI 5.0 provides extensions to the EINJ mechanism to specify the
target for the error injection - by APICID for cpu related errors,
by address for memory related errors, and by segment/bus/device/function
for PCIe related errors. Also extensions for vendor specific error
injections.
Tested-by: Chen Gong <gong.chen@linux.intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/Documentation/acpi/apei/einj.txt b/Documentation/acpi/apei/einj.txt
index 5cc699b..e7cc363 100644
--- a/Documentation/acpi/apei/einj.txt
+++ b/Documentation/acpi/apei/einj.txt
@@ -47,20 +47,53 @@
- param1
This file is used to set the first error parameter value. Effect of
- parameter depends on error_type specified. For memory error, this is
- physical memory address. Only available if param_extension module
- parameter is specified.
+ parameter depends on error_type specified.
- param2
This file is used to set the second error parameter value. Effect of
- parameter depends on error_type specified. For memory error, this is
- physical memory address mask. Only available if param_extension
- module parameter is specified.
+ parameter depends on error_type specified.
-Injecting parameter support is a BIOS version specific extension, that
-is, it only works on some BIOS version. If you want to use it, please
-make sure your BIOS version has the proper support and specify
-"param_extension=y" in module parameter.
+BIOS versions based in the ACPI 4.0 specification have limited options
+to control where the errors are injected. Your BIOS may support an
+extension (enabled with the param_extension=1 module parameter, or
+boot command line einj.param_extension=1). This allows the address
+and mask for memory injections to be specified by the param1 and
+param2 files in apei/einj.
+
+BIOS versions using the ACPI 5.0 specification have more control over
+the target of the injection. For processor related errors (type 0x1,
+0x2 and 0x4) the APICID of the target should be provided using the
+param1 file in apei/einj. For memory errors (type 0x8, 0x10 and 0x20)
+the address is set using param1 with a mask in param2 (0x0 is equivalent
+to all ones). For PCI express errors (type 0x40, 0x80 and 0x100) the
+segment, bus, device and function are specified using param1:
+
+ 31 24 23 16 15 11 10 8 7 0
+ +-------------------------------------------------+
+ | segment | bus | device | function | reserved |
+ +-------------------------------------------------+
+
+An ACPI 5.0 BIOS may also allow vendor specific errors to be injected.
+In this case a file named vendor will contain identifying information
+from the BIOS that hopefully will allow an application wishing to use
+the vendor specific extension to tell that they are running on a BIOS
+that supports it. All vendor extensions have the 0x80000000 bit set in
+error_type. A file vendor_flags controls the interpretation of param1
+and param2 (1 = PROCESSOR, 2 = MEMORY, 4 = PCI). See your BIOS vendor
+documentation for details (and expect changes to this API if vendors
+creativity in using this feature expands beyond our expectations).
+
+Example:
+# cd /sys/kernel/debug/apei/einj
+# cat available_error_type # See which errors can be injected
+0x00000002 Processor Uncorrectable non-fatal
+0x00000008 Memory Correctable
+0x00000010 Memory Uncorrectable non-fatal
+# echo 0x12345000 > param1 # Set memory address for injection
+# echo 0xfffffffffffff000 > param2 # Mask - anywhere in this page
+# echo 0x8 > error_type # Choose correctable memory error
+# echo 1 > error_inject # Inject now
+
For more information about EINJ, please refer to ACPI specification
-version 4.0, section 17.5.
+version 4.0, section 17.5 and ACPI 5.0, section 18.6.