Intel
®
81341 and 81342 I/O Processors
December 2007
Developer’s Manual
Order Number: 315037-002US
275
Address Translation Unit (PCI Express)—Intel
®
81341 and 81342
3.9.1
PCI Express* Errors
PCI Express classifies errors as either Fatal, Uncorrectable or Correctable which allows
the platform to map errors to a suitable handling mechanism. The control and mapping
of errors into each of these categories are provided by the Advanced Error Handling
registers. In addition to the specification defined registers, the ATU provides a duplicate
set of error log in registers (see
“PCI Interface Error Control and Status Register -
) that allows the 81341 and 81342 component to respond to
errors in an application specific fashion.
3.9.1.1
Role Based Error Reporting
In earlier versions of the PCI Express Specification, errors were reported by the agent
that detected the error. The PCI Express Base Specification, Revision 1.1 implements a
role based error reporting where the response to the errors is based on the
components role in the transaction.In general, errors detected in Non Posted
transactions are handled by the initial requestor and the completer may optionally send
an advisory message to the root complex as an ERR_COR message. Errors in Posted
transactions are still logged and reported by the target device.
Note:
When the severity for the error is programmed to fatal in the
Uncorrectable Error Severity - ERRUNC_SEV
register, then it is not an “Advisory Non-
Fatal Error” and is signalled with an ERR_FATAL message. A fatal severity overrides all
other Advisory Error control bits.
The following errors are considered “Advisory Non-Fatal Error” cases and have different
handling depending based on the Transaction type.
The different responses are described in detail in the following sections.
• ECRC Check Failed
• Unexpected Completion
• Unsupported Request (UR)
• Poisoned TLP Received
• Completer Abort (CA)
• Completion Timeout
Table 130. Advisory Error Cases
Error Type
Posted
Non Posted
Completion
ECRC Check Failed
Not an Advisory Error - Send ERR_NONFATAL
Unsupported Request
Not Advisory Error -
Send ERR_NONFATAL
Advisory Error -
Send ERR_COR
Signaled via device driver
Completer Abort
Not Advisory Error -
Send ERR_NONFATAL
Advisory Error -
Send ERR_COR
Signaled via device driver
Unexpected Completion
N/A
N/A
Advisory Error -
Send ERR_COR
Poisoned TLP Received
When PIE_AEC bit 4 is set
then treat as an Advisory
Error - send ERR_COR.
Else Not Advisory Error -
Send ERR_NONFATAL
N/A
When PIE_AEC bit 5is set
then treat as an Advisory
Error - send ERR_COR.
Else Not Advisory Error -
Send ERR_NONFATAL
Completion Timeout
N/A
N/A
When PIE_AEC bit 6is set
then treat as an Advisory
Error - send ERR_COR.
Else Not Advisory Error -
Send ERR_NONFATAL