that is not currently supported in OpenOCD.)
@end deffn
-@deffn Command {armv4_5 disassemble} address count [thumb]
+@deffn Command {armv4_5 disassemble} address [count [@option{thumb}]]
@cindex disassemble
Disassembles @var{count} instructions starting at @var{address}.
-If @option{thumb} is specified, Thumb (16-bit) instructions are used;
+If @var{count} is not specified, a single instruction is disassembled.
+If @option{thumb} is specified, or the low bit of the address is set,
+Thumb (16-bit) instructions are used;
else ARM (32-bit) instructions are used.
(Processors may also support the Jazelle state, but
those instructions are not currently understood by OpenOCD.)
@subsection XScale specific commands
@cindex XScale
+Some notes about the debug implementation on the XScale CPUs:
+
+The XScale CPU provides a special debug-only mini-instruction cache
+(mini-IC) in which exception vectors and target-resident debug handler
+code are placed by OpenOCD. In order to get access to the CPU, OpenOCD
+must point vector 0 (the reset vector) to the entry of the debug
+handler. However, this means that the complete first cacheline in the
+mini-IC is marked valid, which makes the CPU fetch all exception
+handlers from the mini-IC, ignoring the code in RAM.
+
+OpenOCD currently does not sync the mini-IC entries with the RAM
+contents (which would fail anyway while the target is running), so
+the user must provide appropriate values using the @code{xscale
+vector_table} command.
+
+It is recommended to place a pc-relative indirect branch in the vector
+table, and put the branch destination somewhere in memory. Doing so
+makes sure the code in the vector table stays constant regardless of
+code layout in memory:
+@example
+_vectors:
+ ldr pc,[pc,#0x100-8]
+ ldr pc,[pc,#0x100-8]
+ ldr pc,[pc,#0x100-8]
+ ldr pc,[pc,#0x100-8]
+ ldr pc,[pc,#0x100-8]
+ ldr pc,[pc,#0x100-8]
+ ldr pc,[pc,#0x100-8]
+ ldr pc,[pc,#0x100-8]
+ .org 0x100
+ .long real_reset_vector
+ .long real_ui_handler
+ .long real_swi_handler
+ .long real_pf_abort
+ .long real_data_abort
+ .long 0 /* unused */
+ .long real_irq_handler
+ .long real_fiq_handler
+@end example
+
+The debug handler must be placed somewhere in the address space using
+the @code{xscale debug_handler} command. The allowed locations for the
+debug handler are either (0x800 - 0x1fef800) or (0xfe000800 -
+0xfffff800). The default value is 0xfe000800.
+
+
These commands are available to XScale based CPUs,
which are implementations of the ARMv5TE architecture.
@cindex vector_catch
Display a bitmask showing the hardware vectors to catch.
If the optional parameter is provided, first set the bitmask to that value.
+
+The mask bits correspond with bit 16..23 in the DCSR:
+@example
+0x01 Trap Reset
+0x02 Trap Undefined Instructions
+0x04 Trap Software Interrupt
+0x08 Trap Prefetch Abort
+0x10 Trap Data Abort
+0x20 reserved
+0x40 Trap IRQ
+0x80 Trap FIQ
+@end example
+@end deffn
+
+@anchor{xscale vector_table}
+@deffn Command {xscale vector_table} [<low|high> <index> <value>]
+@cindex vector_table
+
+Set an entry in the mini-IC vector table. There are two tables: one for
+low vectors (at 0x00000000), and one for high vectors (0xFFFF0000), each
+holding the 8 exception vectors. @var{index} can be 1-7, because vector 0
+points to the debug handler entry and can not be overwritten.
+@var{value} holds the 32-bit opcode that is placed in the mini-IC.
+
+Without arguments, the current settings are displayed.
+
@end deffn
@section ARMv6 Architecture
@subsection Cortex-M3 specific commands
@cindex Cortex-M3
-@deffn Command {cortex_m3 disassemble} address count
+@deffn Command {cortex_m3 disassemble} address [count]
@cindex disassemble
Disassembles @var{count} Thumb2 instructions starting at @var{address}.
+If @var{count} is not specified, a single instruction is disassembled.
@end deffn
@deffn Command {cortex_m3 maskisr} (@option{on}|@option{off})
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