Routing Errors - Renesas IDT 89HPES48H12G2 User Manual

IDT Theory of Operation
Notes
PES48H12G2 User Manual
Note the following:
– Except for ECRC and Poisoned TLP errors, all other errors detected on the received TLP cause
the detecting function to consume, drop, or nullify the TLP.
– Receiver overflow errors are only checked and logged.
– ECRC errors are only checked and logged when the TLP has passed receiver overflow checks.
Per the error handling rules in Table 9.9, a TLP with ECRC error may result in the TLP being
forwarded across the PCI-to-PCI bridge function. Such TLPs are subject to further error checking
by the receiving function.
– TLP malformation errors are only logged and reported when the TLP has passed ECRC error
checking. Still, a TLP with ECRC error that is not dropped as a result of the ECRC error is subject
to TLP malformation error checking since the higher priority ECRC error does not inhibit the
checking of the lower-priority malformation error.
• In case the TLP with ECRC error is malformed, the TLP is nullified (per the error handling rules
in Table 9.9) but the malformed TLP error is not logged in AER.
– ACS errors violations are only logged and reported when the TLP has passed malformation and
ECRC checks. Still, a TLP with ECRC error that is not dropped as a result of the higher priority
errors is subject to ACS blocking or re-direction since the higher priority ECRC error does not
inhibit the checking of the lower-priority ACS checks.
• In case the TLP with ECRC error is blocked by an ACS check (e.g., ACS Source Validation), the
blocking action takes place but the ACS error is not logged and a completion with 'completer-
abort' status is not generated.
– Multicast blocking errors are only logged and reported when the TLP has passed ECRC, malfor-
mation, and ACS violation checks. Still, a TLP with ECRC error that is not dropped as a result of
the higher priority errors is subject to multicast blocking checks since the higher priority ECRC
error does not inhibit the checking for multicast blocking errors.
• In case the TLP with ECRC error is blocked by the multicast blocking check, the blocking action
takes place but a multicast blocking error is not logged.
– Unsupported request errors are only logged and reported when the request TLP has passed
ECRC, malformation, ACS violation, and multicast blocking checks. Still, an unsupported request
TLP that is not dropped as a result of the higher priority errors is subject to unsupported request
handling.
• In case the TLP with ECRC error is an unsupported request, the TLP is handled per the rules in
Table 9.9 but the unsupported is not logged in AER and a completion TLP is not generated.
– Finally, poisoned TLP errors are only logged when the TLP has passed ECRC, malformation, ACS
violation, multicast blocking, unsupported request, and unexpected completion checks (i.e., the
TLP is a valid request or completion claimed by a port function).
• Per the error handling rules in Table 9.9, poisoned TLP may be forwarded across the PCI-to-PCI
bridge function.
For example, when a downstream port receives a posted memory request TLP from the link with an
1
ECRC error , the port's PCI-to-PCI bridge function will handle the TLP as described in Table 9.9 and Table
9.13. Because ECRC error has higher priority than other errors, only the ECRC error is logged in the port's
AER Capability Structure. If the TLP targets the receiving port (i.e., the port is the 'ultimate receiver' of the
TLP), the TLP is dropped and no further checking is required. If the port that received the TLP is an interme-
diate receiver, the TLP is not dropped due to the ECRC error and thus the port performs lower priority error
checks and takes the appropriate action. In this example, if the TLP results in an unsupported request error
(e.g., the BME bit in the function's PCICMD register is cleared), the port consumes the TLP, does not log
the UR error, and does not generate a completion TLP as a result of the UR error.

Routing Errors

This section lists TLP routing errors that are detected by the PCI-to-PCI bridge function in the
PES48H12G2 ports. Except for completions (section Completions (Routed by ID) on page 9-17), all of
these errors are treated as unsupported requests.
1.
Assuming that the reception of the TLP did not cause a receiver overflow error on the port.
9 - 16 April 5, 2013