Advanced Configuration and Power Interface Specification

ACPI Platform Error Interfaces (APEI)
Field
Poll Interval 4 4 Indicates the poll interval in milliseconds OSPM should use to
periodically check the error source for the presence of an error
condition.
Vector 4 8 Interrupt vector.
Switch To Polling
Threshold Value
Switch To Polling
Threshold Window
Error Threshold
Value
Error Threshold
Window
Byte
Length
Byte
Offset
Description
4 12 The number of error interrupts that must occur within Switch To
Polling Threshold Interval before OSPM switches the error source
to polled mode.
4 16 Indicates the time interval in milliseconds that Switch To Polling
Threshold Value interrupts must occur within before OSPM
switches the error source to polled mode.
4 20 Indicates the number of error events that must occur within Error
Threshold Interval before OSPM processes the event as an error
condition.
4 24 Indicates the time interval in milliseconds that Error Threshold
Value errors must occur within before OSPM processes the event
as an error condition.
18.4 Firmware First Error Handling
It may be necessary for the platform to process certain classes of errors in firmware before
relinquishing control to OSPM for further error handling. Errata management and error containment
are two examples where firmware-first error handling is beneficial. Generic hardware error sources
support this model through the related source ID.
The platform reports the original error source to OSPM via the hardware error source table (HEST)
and sets the FIRMWAREFIRST flag for this error source. In addition, the platform must report a
generic error source with a related source ID set to the original source ID. This generic error source
is used to notify OSPM of the errors on the original source and their status after the firmware first
handling.
There are different notification strategies that can be used in firmware first handling; the following
options are available to the platform:
• Traditional ACPI platforms may use NMI to notify the OSPM of both corrected and uncorrected
errors for a given error source
• Traditional ACPI platforms may use NMI to report uncorrected errors and the SCI to report
corrected errors
• Traditional ACPI platforms may use NMI to report uncorrected errors and polling to notify the
OSPM of corrected errors
• HW-reduced ACPI platforms may use GPIO-signaled events or polling to report corrected
errors.
Version 6.0 729