ACPI, APEI, Document for APEI
Add document for APEI, including kernel parameters and EINJ debug file
sytem interface.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.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
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index 0000000..838b7f0
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+ APEI Error INJection
+ ~~~~~~~~~~~~~~~~~~~~
+
+EINJ provides a hardware error injection mechanism
+It is very useful for debugging and testing of other APEI and RAS features.
+
+To use EINJ, make sure the following are enabled in your kernel
+configuration:
+
+CONFIG_DEBUG_FS
+CONFIG_ACPI_APEI
+CONFIG_ACPI_APEI_EINJ
+
+The user interface of EINJ is debug file system, under the
+directory apei/einj. The following files are provided.
+
+- available_error_type
+ Reading this file returns the error injection capability of the
+ platform, that is, which error types are supported. The error type
+ definition is as follow, the left field is the error type value, the
+ right field is error description.
+
+ 0x00000001 Processor Correctable
+ 0x00000002 Processor Uncorrectable non-fatal
+ 0x00000004 Processor Uncorrectable fatal
+ 0x00000008 Memory Correctable
+ 0x00000010 Memory Uncorrectable non-fatal
+ 0x00000020 Memory Uncorrectable fatal
+ 0x00000040 PCI Express Correctable
+ 0x00000080 PCI Express Uncorrectable fatal
+ 0x00000100 PCI Express Uncorrectable non-fatal
+ 0x00000200 Platform Correctable
+ 0x00000400 Platform Uncorrectable non-fatal
+ 0x00000800 Platform Uncorrectable fatal
+
+ The format of file contents are as above, except there are only the
+ available error type lines.
+
+- error_type
+ This file is used to set the error type value. The error type value
+ is defined in "available_error_type" description.
+
+- error_inject
+ Write any integer to this file to trigger the error
+ injection. Before this, please specify all necessary error
+ parameters.
+
+For more information about EINJ, please refer to ACPI specification
+version 4.0, section 17.5.