Interrupts and Exceptions
e200z3 Power Architecture Core Reference Manual, Rev. 2
4-14
Freescale Semiconductor
4.6.4
Instruction Storage Interrupt (IVOR3)
An instruction storage interrupt (ISI) occurs when no higher priority exception exists and an execute
access control exception occurs. This interrupt is implemented as defined by Book E, except for the
following:
•
The byte-ordering condition does not occur in the e200z3
•
The addition of precise external termination errors that occur when an instruction fetch is
terminated by assertion of a p_i_tea_b=ERROR termination response and MSR[EE]=1
•
Misaligned instruction fetch exceptions
•
The extension of the byte ordering exception cases.
Exception extensions implemented in e200z3 for VLE involve extending the definition of the instruction
storage interrupt to include the following:
•
Byte-ordering exceptions for instruction accesses
•
Misaligned instruction fetch exceptions
•
Corresponding updates to the ESR as shown in
.
lists register settings when an ISI is taken.
MSR
UCLE 0
SPE 0
WE
0
CE
—
EE
0
PR
0
FP
0
ME
—
FE0
0
DE
—
FE1
0
IS
0
DS
0
RI
—
ESR
Access:
Byte ordering:
External termination error (precise):
[ST], [VLEMI]. All other bits cleared.
[ST], [VLEMI], BO. All other bits cleared.
[ST], [VLEMI], XTE. All other bits cleared.
MCSR
Unchanged
DEAR
For access and byte-ordering exceptions, set to the effective address of a byte within the page whose access caused
the violation.
Vector
IVPR[32–47] || IVOR2[48–59] || 0b0000
Table 4-12. ISI Exceptions and Conditions
Interrupt Type
IVOR
Causing Conditions
Instruction
storage
IVOR 3
• Access control.
• Precise external termination error (
p_tea_b
assertion and precise recognition) and MSR[EE]=1.
• Byte ordering due to misaligned instruction across page boundary to pages with mismatched
VLE bits, or access to page with VLE set, and E indicating little-endian.
• Misaligned Instruction fetch due to a change of flow to an odd halfword instruction boundary on
a Book E (non-VLE) instruction page, due to value in LR, CTR, or xSRR0
Table 4-11. Data Storage Interrupt Register Settings (continued)
Registe
r
Setting Description