Intel 460GX - Manual (Page 126)

Data Integrity and Error Handling
6-28 Intel® 460GX Chipset Software Developer’s Manual
6.12.5.1 SERR# Generation
Most errors can be caused to steer the observation of the error to the signaling of an SERR# . The
system then has a chance to respond to the event while it continues to run. Often, SERR# results in
an NMI which itself often results in a system hang. If the WXB is configured to cause an SERR#
the system should be configured with a usable NMI handler or wired in such a way that an SERR#
is not escalated into an NMI .
Alternatively, the WXB can be configured to cause an INTRQ# interrupt or an XBINIT# instead of
(or in addition to) an SERR# . This is achieved by having any unmasked errors (errors configured
such that they might cause an SERR# ) directed to cause the specified event, be it an INTRQ# or
an XBINIT# .
SERR# signaling itself is ultimately controlled by appropriately setting or clearing the SERRE bit
in the PCICMD register. If set then unmasked errors will result in SERR# being signaled.
Otherwise, even unmasked errors will not cause an SERR# .
Whenever the WXB actually signals an SERR# the SSE bit in the PCISTS register will be set. If
another agent has caused an SERR# then the SES bit in the FEPCI (or NEPCI ) register will be
set.
Note: When multiple errors, which cause an SERR# assertion, occur within a few cycles of each other,
there may not be a separate SERR# assertion for each.
Table 6-4. Supported Error Escalation to SERR_OUT#
a
a. To obtain the listed escalation, the following settings are required: ASAPE=’1’, and ASDTE=’1’.
ASDPE
ERRCMD(11)
ASFPE
ERRCMD(9)
SERRE
PCICMD(8)
PERRE
PCICMD(6)
SERR_OUT#
Escalation
X X 0 X HPSERR, OSERR
0 0 1 0 HPSERR, OSERR, DTE
0 0 1 1 HPSERR, OSERR, DTE, APE
0 1 1 0 HPSERR, OSERR, DTE, OPERR, HPPERR,
PUIQ
0 1 1 1 HPSERR, OSERR, DTE, APE, OPERR,
HPPERR, PUIQ
1 0 1 0 HPSERR, OSERR, DTE, FUIQ, PCIDPE
1 0 1 1 HPSERR, OSERR, DTE, APE FUIQ, PCIDPE
1 1 1 0 HPSERR, OSERR, DTE, FUIQ, PCIDPE,
OPERR, HPPERR, PUIQ
1 1 1 1 HPSERR, OSERR, DTE, APE FUIQ, PCIDPE,
OPERR, HPPERR, PUIQ
Table 6-5. Supported Error Escalation to P(A/B)INTRQ#
IRQE
ERRCMD(13)
P(A/B)INTRQ#
0 OFF
1 OPERR, HPPERR, PUIQ