[PATCH] spec/cpukit: Omit Cortex-M from libdebugger build

[Kinsey Moore]

On Wed, Aug 16, 2023 at 9:42 PM Chris Johns <chrisj at rtems.org> wrote:

> On 17/8/2023 6:30 am, Kinsey Moore wrote:
> > The current ARM support in libdebugger does not cover Cortex-M series
> > cores since it requires support for CP14 system register accessor
> > instructions. Cortex-M series cores support debug monitor mode, but its
> > configuration is accessed by memory mapped registers instead of using
> > CP14. This omits building libdebugger from BSPs that use a cortex-m ABI
> > flag.
>
> The ARM libdebugger has support to use memory mapped registers. It is
> determined
>  by the ROM and then rtems_debugger_arm_debug_registers. I think the code
> currently assume CP14 instructions but I think that could be made
> conditional
> where needed?
>
> Are these builds of Cortex-M processors able to support libdebugger?
>
> I have been rejecting changes like this unless there is a reason it cannot
> be
> made to work. Are there reasons it cannot be made to work?
>

As to my current understanding, I believe that the Cortex-M3/4/7 cores can
support libdebugger via their exclusive monitor mode. I'll see if I can
work around the CP14 issues instead.

Kinsey
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.rtems.org/pipermail/devel/attachments/20230817/ed3d6458/attachment.htm>