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ARMulator Reference
4.4.4
MRC
This function is called when an MRC instruction is recognized for a coprocessor. If the
requested coprocessor register does not exist or cannot be written to, the function must
return ARMul_CP_CANT.
Syntax
unsigned MRC(void *handle, int type, ARMword instr, ARMword *data)
where:
handle
is the handle from ARMulif_InstallCoprocessorV5.
type
is the type of the coprocessor access. This can be one of:
ARMul_CP_FIRST
indicates that this is the first time the coprocessor
model has been called for this instruction.
ARMul_CP_BUSY
indicates that this is a subsequent call, after the first
call was busy-waited.
ARMul_CP_INTERRUPT warns the coprocessor that the ARM is about to
service an interrupt, so the coprocessor must
discard the current instruction. Usually, the
instruction will be retried later, in which case the
type will be reset to ARMul_CP_FIRST.
ARMul_CP_DATA
indicates that valid data is included in *data.
instr
is the current opcode.
data
is a pointer to the location of the data being transferred from the
coprocessor to the core.
Return
The function must return one of:
ARMul_CP_DONE, to indicate that the coprocessor operation is complete, and valid
•
data has been returned to *data.
•
ARMul_CP_BUSY, to indicate that the coprocessor is busy
•
ARMul_CP_CANT, to indicate that the instruction is not supported, or the specified
register cannot be accessed.
ARM DUI0058D
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