boards: arm: rpi_pico: add openocd runner configuration

[soburi]

Add openocd configuration.

This configuration allows selecting what debug adapter debugging rpi_pico
by a command-line argument.
It is mainly intended to support both the 'picoprobe' and 'raspberrypi-swd'
adapter described in "Getting started with Raspberry Pi Pico".
And any other SWD debug adapter might also be usable with this configuration.

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[yonsch]

Looking good overall, I have just one question:
Does this work with the openocd found in zephyr-sdk, or does it use a custom version of openocd? I couldn't find target/rp2040.cfg (though I did find rp2040-core0.cfg), and neither interface/picoprobe/interface/raspberrypi-swd.

[soburi]

Hi! @yonsch
Thanks for reviewing.

Looking good overall, I have just one question: Does this work with the openocd found in zephyr-sdk, or does it use a custom version of openocd? I couldn't find target/rp2040.cfg (though I did find rp2040-core0.cfg), and neither interface/picoprobe/interface/raspberrypi-swd.

It requires a custom version openocd.

I missed writing information about the distribution source of the custom version.
(https://github.com/raspberrypi/openocd)
I will add some information about that version.

There is an easy way to use this version of openocd is running the setup.sh script for setting up the pico development environment. I wrote it in the document.

[burumaj]

I tested this yesterday evening with the picoprobe. There are couple remarks I have regarding the documentation of this:

1. when using the picoprobe adding a udev rule might be necessary so a regular user can use it with openocd (or at least a user that is in de plugdev group in this case).

# Raspberry Pi Picoprobe
ATTRS{idVendor}=="2e8a", ATTRS{idProduct}=="0004", MODE="660", GROUP="plugdev", TAG+="uaccess"

2. When using an openocd not included with the zephyr sdk there is not rtos support for zephyr. The consequence of this is that it's possible to use openocd to debug an application, but only without thread awareness.

3. You mention the use of picosetup.sh, this script and is only supported on piOS, and probably works fine on debian based systems like ubuntu.

[soburi]

Hi, @burumaj

I tested this yesterday evening with the picoprobe. There are couple remarks I have regarding the documentation of this:

Thanks for testing it and comments.
I updated the document with apply your mentions.

[yonsch]

Thanks, a few comments about the documentation.

[yonsch]

Now that you've added a link, this line can be removed.

[soburi]

I removed this line.

[yonsch]

Too many blank lines

[soburi]

Fix it

[MeisterBob]

I would suggest adding jlink support to board.cmake as well

board_runner_args(jlink "--device=RP2040_M0_0")
include(${ZEPHYR_BASE}/boards/common/jlink.board.cmake)

[soburi]

Hi, @MeisterBob

Thanks for comment.

I would suggest adding jlink support to board.cmake as well

board_runner_args(jlink "--device=RP2040_M0_0")
include(${ZEPHYR_BASE}/boards/common/jlink.board.cmake)

It seems good.
And this code is your contribution.
So, I think it is better to create your PR.
(In another view, it keeps simple PR.)
Or Reporting as issue is also good way.

Please consider it.

[soburi]

@MeisterBob ,
I split the topic about J-Link support to new issue.
#48194

(Simply reason, I can't verify the code within this PR becasuse I don't have J-Link debugger...)