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Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/acpi/apei/einj.txt | 55 |
1 files changed, 44 insertions, 11 deletions
diff --git a/Documentation/acpi/apei/einj.txt b/Documentation/acpi/apei/einj.txt index 5cc699ba5453..e7cc36397217 100644 --- a/Documentation/acpi/apei/einj.txt +++ b/Documentation/acpi/apei/einj.txt @@ -47,20 +47,53 @@ directory apei/einj. The following files are provided. - 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. + +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 -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. 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. |