CHAPTER 2 VR4120A
Preliminary User’s Manual S15543EJ1V0UM 159
Figure 2-61. Common Exception Handling (1/2)(a) Handling Exceptions other than Cold Reset, Soft Reset, NMI, and TLB/XTLB Refill (Hardware)
BD bit1
EPCPC4
EXL1
Kernel mode is set and interrupts
are disabled.
= 0 (Normal) = 1 (bootstrap)
Check for multiple exceptions
Kernel mode is set and interrupts are
disabled.
EntryHi and X/Context registers are set only
when a TLB Refill, TLB Invalid, or TLB
Modified exception occurs.
X/ContextVPN2
Entry HiVPN2, ASID
Set Cause register (ExcCode, CE)
)
To guidelin e to common exc eption han dler
Start
Yes
EXL = 1?
(SR1)
No
NoYes Instruction
in branch delay
slot?
BEV
PCFFFF FFFF BFC0 0200H +180H
(Unmapped, uncached space)
M16 = 1?
(config20)
PCFFFF FFFF 8000 0000H +180H
(Unmapped, cacheable space)
No Instruction
in delay slot?
BD bit1
EPCPC4
EPCEIM
BD bit0
EPCPC
EPCEIM
NoYes
Yes
BD bit0
EPCPC
BadVAddr is set only when a TLB Refill, TLB
Invalid, or T LB Modi fied excep tion occ urs
(BadVAddr is not set when a Bus Error exception
occurs).
Remark The interrupts can be masked by setting the IE or IM bit.The Watch exception can be set to pending state by setting the EXL bit to 1.