Intel
®
IXP45X and Intel
®
IXP46X Product Line of Network Processors
August 2006
Developer’s Manual
Order Number: 306262-004US
955
Error Handling—Intel
®
IXP45X and Intel
®
IXP46X Product Line of Network Processors
• Software can reset the errored NPE by writing to Bits 13:11 of the
EXP_UNIT_FUSE_REG register defined in the Expansion Bus chapter. Please note
resetting the NPE resets the core and all the coprocessors associated with that NPE.
• The Expansion bus unit hardware handshakes with the NPE hardware to indicate
that the AHB Bus transactions must be terminated cleanly (and the AHB Bus itself
doesn't hang).
• The NPE hardware indicates to the Expansion Bus unit hardware that is it ready to
be reset.
• The NPE then goes into reset state.
• The coprocessors on the NPE are also reset. The state of the coprocessors and the
state of the pins are described below:
Table 299.
NPE Coprocessor Response
NPE Coprocessor
NPE Error
ERR_EN
NPE Coprocessor Response
AHB Coprocessor
Asserted
1
The AHB Coprocessor will lock-up and not accept new
transfers.
Asserted
0
Error happened but the coprocessor continues Normal
operation as if no error happened
Deasserted
X
No error, continues Normal operation
Ethernet Coprocessor
Asserted
1
The transmit Enable signal (ecp_tx_en) will be forced to
inactive state effectively ending all transmission
immediately
Asserted
0
Error happened but the coprocessor continues Normal
operation as if no error happened.
Deasserted
X
No error, continues Normal operation
UTOPIA Coprocessor
Asserted
1
The transmit Enable signal (UTP_OP_FCO) will be forced to
inactive state effectively ending all transmission
immediately
Asserted
0
Error happened but the coprocessor continues Normal
operation as if no error happened
Deasserted
X
No error, continues Normal operation
Switching Coprocessor
X
X
In case of a parity error, continue operation without
locking up. For example, if an error happened during
insertion of an entry into the CAM, the SWCP will indicate
unsuccessful completion of operation and will not lock-up.
But the SWCP will assert an interrupt to the Intel XScale
®
Processor indicating the parity error.
Other Coprocessors
X
X
In case of a parity error, continue operation without
locking up.