FUJITSU Implementation Supplement Fujitsu SPARC64 V User Manual
Page 166
Release 1.0, 1 July 2002
F. Chapter P
Error Handling
155
Action upon the
error detection
1. CPU enters
CPU fatal
state.
2. CPU informs
the system of
fatal error
occurrence.
3. The FATAL
reset (which is
a form of POR
reset) is issued
to the whole
system.
4. POR reset is
caused to all
CPUs in the
system.
1. CPU enters
error_state
.
2. Watchdog reset
(WDR) is caused
on the CPU.
Detection of
I_UGE
When
ASI_ECR.UGE_HANDLER
= 0,
a single-
ADE
trap is caused.
Otherwise, when
ASI_ECR.UGE_HANDLER
= 1,
a multiple-
ADE
trap is caused.
Detection of
A_UGE
When the trap is enabled, a
single-
ADE
trap is caused.
When the trap is disabled, the
trap condition is kept pending
in hardware.
Detection of
IAE
When
ASI_ECR.UGE_HANDLER
= 0,
an
IAE
trap is caused. Other-
wise, a multiple-
ADE
trap is
caused.
Detection of
DAE
When
ASI_ECR.UGE_HANDLER
= 0,
a
DAE
trap is caused. Other-
wise, a multiple-
ADE
trap is
caused.
Ideal specification
1. The error detection is kept
pending in one bit of
ASI_AFSR
.
2. When the trap condition
for the pending error
detection is enabled, the
ECC_error
exception is
generated.
Deviation in SPARC64 V
An
ECC_error
trap can occur
even though
ASI_AFSR
does not indicate any
detected error(s)
corresponding to any trap-
enable bit (
RTE_UE
or
RTE_CEDG
) set to 1 in
ASI_ECR
, in the following
cases:
1. A pending detected error
is erased from
ASI_ASFR
(by writing
1
to
ASI_AFSR
) after the error
is detected but before the
ECC_error
trap is
generated.
2. A pending
CE
or
DG
is
erased by writing 1 to
ASI_AFSR
after the
ECC_error
trap is caused
by the
UE
error detection.
3. A pending
UE
is erased by
writing 1 to
ASI_AFSR
after the
ECC_error
trap is
caused by
CE
or
DG
detection.
Privileged software should
ignore an
ECC_error
trap
when the
AFSR
contains no
errors corresponding to
those enabled in
ASI_ECR
to cause a trap.
Priority of
action when
multiple types
of errors are
simultaneously
detected
1 — CPU fatal
state
2 —
error_state
3 —
ADE
trap
4 —
DAE
trap
5 —
IAE
trap
6 —
ECC_error
trap
TABLE P-2
Action Upon Detection of an Error (2 of 4)
Fatal Error (FE)
Error State Transition
Error (EE)
Urgent Error (UGE)
Restrainable Error (RE)