West: openocd runner: Don't let debug mode on by default

[erwango]

Describe the bug
When flashing using openocd runner, the cortex-m processor is left in debug mode. It can, then, only be released after a power-on reset (cold reset).

This conflicts with the use of #31481 (Null pointer exception detection via DWT), and prevent its use by default in tests.

For this reason, Null pointer exception detection was disabled by default on all STM32 platforms, but it would be great to be able to re-instantiate it.

Note: This potentially affect other runners as well (pyocd, for instance).

To Reproduce
Steps to reproduce the behavior:

1. Revert soc: stm32: Disable null pointer exception detection by default #32983
2. Run any zephyr test on a STM32 target using openocd runner for flashing
3. See error

Expected behavior
Don't prevent use of Null pointer exception detection when using openocd runner

Impact
Prevent use of Null pointer exception detection when using openocd runner in zephyr tests

Logs and console output
If applicable, add console logs or other types of debug information
e.g Wireshark capture or Logic analyzer capture (upload in zip archive).
copy-and-paste text and put a code fence (```) before and after, to help
explain the issue. (if unable to obtain text log, add a screenshot)

Environment (please complete the following information):

• OS: (e.g. Linux, MacOS, Windows)
• Toolchain (e.g Zephyr SDK, ...)
• Commit SHA or Version used

Additional context
Add any other context about the problem here.

[ioannisg]

Thanks for the ticket @erwango
To the best of my knowledge, pyocd, jlink, or nrfjprog are not affected. I've tried with several boards/runners and this seems to be the case.

[ioannisg]

Guess the main issue here is that we do not have a consistent west flash, with respect to the state the core is left at, after west flash is done.

[ioannisg]

@mbolivar-nordic can you take a look here (or suggest alternative maintainer)?

[nashif]

looks like pyocd is also affected

see #32966

[mbolivar-nordic]

@mbolivar-nordic can you take a look here (or suggest alternative maintainer)?

Sorry @ioannisg, I don't know enough about the underlying debug IPs to really help here. I see you already posted a PR for openocd, so it seems like you're on your own here :(.

[github-actions]

This issue has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this issue will automatically be closed in 14 days. Note, that you can always re-open a closed issue at any time.