Intel
®
82575EB Gigabit Ethernet Controller — Error Pollution
Intel
®
82575EB Gigabit Ethernet Controller 324632-003
Software Developer’s Manual and EEPROM Guide Revision: 2.1
184 January 2011
6.4.2 Error Pollution
Error pollution can occur if error conditions for a given transaction are not isolated to the error’s first
occurrence. If the Physical Layer detects and reports a Receiver Error, to avoid having this error
propagate and cause subsequent errors at upper layers, the same packet is not signaled at the Data
Link or Transaction layers.
Similarly, when the Data Link Layer detects an error, subsequent errors, which occur for the same
packet, are not signaled at the Transaction Layer.
6.4.3 Unsuccessful Completion Status
A completion with an unsuccessful completion status is dropped and not delivered to its destination.
The request that corresponds to the unsuccessful completion is retried by sending a new request for the
undeliverable data.
6.4.4 Error Reporting Changes
The Revision 1.1 PCI specification defines two changes to advanced error reporting. A (new) Role-
Based Error Reporting bit in the Device Capabilities register is set to 1b to indicate that these changes
are supported by the 82575.
1. Setting the SERR# Enable bit in the PCI Command register also enables UR reporting (in the same
manner that the SERR# Enable bit enables reporting of correctable and uncorrectable errors). The
SSERR# Enable bit overrides the UR Error Reporting Enable bit in the PCI Express Device Control
register.
Malformed TLP
(MP)
• Data payload exceeds
maximum payload size.
• Received TLP data size does
not match length field.
• TD field value does not
correspond with the observed
size.
• Byte enables violations.
• PM messages that do not use
TC0.
• Usage of unsupported VC.
Uncorrectable.
ERR_FATAL.
Log header.
Packet dropped. Free flow control
credits.
Completion with
Unsuccessful
Completion Status
No action (already done by
originator of completion).
Free FC credits.
Byte count
integrity
When byte count isn't compatible
with the length field and the
actual expected completion
length. For example, length field
is 10 (in Dword), actual length is
40, but the byte count field that
indicates how many bytes are
still expected is smaller than 40,
which is not reasonable.
Uncorrectable.
ERR_FATAL
The 82575 doesn’t check for this
error and accepts these packets.
This might cause a completion
timeout condition.
Table 58. Response and Reporting of Error Events
Error Types Error Events Default Severity Action