FUJITSU Implementation Supplement Fujitsu SPARC64 V - Manual (Page 163)

152 SPARC JPS1 Implementation Supplement: Fujitsu SPARC64 V • Release 1.0, 1 July 2002
When the resource with the error is used, the program cannot continue
execution, or the
error_state transition error or the fatal error is detected.
■
The error in an important resource that is expected to invoke the operating
system “panic” process
The operating system panic process is expected when this error is detected
because the normal processing cannot be expected to continue when this error
occurs.
The A_UGE is a disrupting error with the following deviations.
■
The trap for A_UGE is not masked by PSTATE.IE .
■
The instruction designated by TPC may not end precisely. The instruction end-
method is reported in the trap status register for A_UGE .
Traps for Urgent Errors
When an urgent error is detected and not masked, the error is reported to privileged
software by the following exceptions:
■ I_UGE , A_UGE : async_data_error exception
■ IAE : instruction_access_error exception
■ DAE : data_access_error exception
P.1.4 Restrainable Error
A restrainable error is one that does not adversely affect the currently executing
program and that does not require immediate handling by privileged software. A
restrainable error causes a disrupting trap with low priority.
There are three types of restrainable errors.
■ Correctable Error ( CE ), corrected by hardware
Upon detecting the CE , the hardware uses the data corrected by hardware. So a CE
has no deleterious effect on the CPU.
When a CE is detected, data seen by the CPU has always already been corrected
by hardware, but it depends on the CE type whether the original data containing
the CE is corrected or not.
■ Uncorrectable error without direct damage to the currently executing
instruction sequence.
An error detected in cache line writeback or copyback data is of this type.