Intel
®
81341 and 81342 I/O Processors
December 2007
Developer’s Manual
Order Number: 315037-002US
547
System Controller (SC) and Internal Bus Bridge—Intel
®
81341 and 81342
6.3.7
Error Detection and Handling
The Bridge provides a set of error logging registers that are used to log any error that
are encountered by the Bridge: north interface or south interface. Only one error is
logged, when more errors occur when one error is already logged, the bridge would
indicate that it detected more errors, but does not log these newer errors.
The bridge drives a single interrupt (South Internal Bus Bridge Error Interrupt Pending)
to the Interrupt Controller Unit (ICU). An interrupt may be generated by the bridge to
report any error condition detected to the Intel XScale
®
processor by setting bit 16 of
BECSR. Whenever the bridge toggles bit 0 of BECSR from 0 to 1, an interrupt is
generated to the core.
6.3.7.1
Bridge North Internal Bus Interface Error
The following conditions may be encountered by the Bridge North Interface:
• Master Abort on the North Internal Bus interface. This condition may happen when
the bridge attempts an address request on the north internal bus and the request is
not claimed by any target. The bridge would log the error as a Master Abort.
— For a write request, the bridge simply logs the master abort error condition and
discard the write data.
— For a read request, the Bridge logs the Master Abort. In addition, the Bridge
completes the read completion as follows: it indicates to the initiating agent on
the south internal bus that it encountered an error by performing a target abort
during the read completion.
• Address Request Error on the north internal bus interface. This condition may
happen when a target on the north internal bus detected an error during the
address request. For example, the target may indicate that the byte-count is out of
range.
— For a write request, the bridge logs the address request error condition and
discard the write data.
— For read request, the Bridge logs the address request error. In addition, the
Bridge completes the read completion as follows: it indicates to the initiating
agent on the south internal bus that it encountered an error by performing a
target abort during the read completion.
• Target Abort on the north internal bus. This condition may occur when a target
claimed a previously issued read request, but is unable to return the read
completion data. The bridge would log the error as a target abort.
— The Bridge logs the target abort. In addition, the Bridge completes the read
completion as follows: it indicates to the initiating agent on the south internal bus
that it encountered an error by performing a target abort during the read
completion. Target Abort on the north internal bus. This condition may occur
when the north interface detects a parity error during the data phase of a write
request to the north internal bus, or during a read completion to the north
internal bus.
— For a read completion, the Bridge logs the target abort condition and completes
the read completion as follows: it indicates to the initiating agent on the north
internal bus that it encountered an error by performing a target abort during
the read completion. For a write transaction, the Bridge logs the target abort
condition and completes the write transaction on the north internal bus.