Freescale Semiconductor PowerPC e500 Core, Reference Manual

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PowerPC e500 Core Family Reference Manual, Rev. 1
5-20 Freescale Semiconductor
Interrupts and Exceptions
NOTE
icbi and icbt are treated as loads from the addressed byte with respect
to address translation and protection. They use MSR[DS], not
MSR[IS], to determine translation for their operands. Instruction
storage interrupts and instruction TLB error interrupts are associated
with instruction fetching and not execution. Data storage interrupts
and data TLB error interrupts are associated with the execution of
instruction cache management instructions.
When a data storage interrupt occurs, the processor suppresses execution of the instruction causing
the data storage exception. SRR0, SRR1, ESR, MSR, and DEAR, are updated as follows:
Instruction execution resumes at address IVPR[32–47] || IVOR2[48–59] || 0b0000.
5.7.4 Instruction Storage Interrupt
An instruction storage interrupt occurs when no higher priority exception exists and an instruction
storage exception is presented to the interrupt mechanism. Instruction storage exception
conditions are described in
Table 5-13 .
Table 5-12. Data Storage Interrupt Register Settings
Register Setting
SRR0 Set to the effective address of the instruction causing the interrupt
SRR1 Set to the MSR contents at the time of the interrupt
ESR ST Set if the instruction causing the interrupt is a store or store-class cache management instruction; otherwise
cleared
DLK DLK is set when a DSI occurs because dcbtls , dcbtstls , or dcblc is executed in user mode and MSR[UCLE] = 0.
BO Set if the instruction caused a byte-ordering exception; otherwise cleared
All other defined ESR bits are cleared.
MSR CE, ME, and DE are unchanged. All other MSR bits are cleared.
DEAR Set to the effective address of a byte that lies both within the range of bytes being accessed by the access or cache
management instruction and within the page whose access caused the exception
Table 5-13. Instruction Storage Interrupt Exception Conditions
Exception Cause
Execute access
control exception In user mode, an instruction fetch attempts to access a memory location that is not user mode execute
enabled (page access control bit UX = 0).
In supervisor mode, an instruction fetch attempts to access a memory location that is not supervisor mode
execute enabled (page access control bit SX = 0).
Byte-ordering
exception The implementation cannot fetch the instruction in the byte order specified by the page’s endian attribute.
The EIS defines that accesses that cross a page boundary such that endianness changes cause a
byte-ordering exception.