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Symbolic Debugger
7.12
Coprocessor Support
The symbolic debugger’s coprocessor support allows access to registers of a coprocessor
through a debug monitor which is ignorant of the coprocessor. This is only possible if the registers
of the coprocessor are read (if readable) and written (if writeable) by a single coprocessor data
transfer (CPDT) or a coprocessor registers transfer (CPRT) instruction in a non-user mode. For
coprocessors with more exotic registers, there must be support code in a debug monitor.
7.12.1 Coproc
This command describes the register set of a coprocessor and specifies how the contents of the
registers are formatted for display. The syntax is:
c{oproc} cpnum {regdesc}*
regdesc may describe one register, or a range of registers which are accessed and are to be
formatted uniformly. It has the syntax:
rno{:rno1}
size access-specifiers access-values {displaydesc}*
where:
size
is the register size (in bytes)
access-specifiers may comprise the letters:
access-values
R
the register is readable
W
the register is writeable
D
the register is accessed through CPDT instructions (if
this is not present, the register is accessed through
CPRT instructions).
the format of this option depends whether the register is to be
accessed through CPRT instructions.
If so, it comprises four integer values separated by space or comma:
r0_7, r16_23, w0_7, w16_23
to form bits 0 to 7 and 16 to 23 of a MRC instruction to read the
register, and bits 0 to 7 and 16 to 23 of a MCR instruction to write the
register.
If not, it comprises two integer values:
b12_15, b22
to form bits 12 to 15 and bit 22 of CPDT instructions to read and write
the register.
displaydesc
7-30
is one of the items listed in ➲Table 7-3: Displaying the contents of
coprocessor registers on page 7-31.
Reference Manual
ARM DUI 0020D