arm-none-eaby-gdb-py + openocd

[dunklecat]

How to make arm-none-eaby-gdb-py + openocd work?

Hi all! I'm trying to set up dape to debug a STM32 nucleo board for a personal project using openocd as the gdb server. I can't make it work and I don't know why. I tried using a .gdbinit file, put everything inside my .dir-locals and whatnot. When I use the fields like :target I avoid the .gdbinit. I tried to understand the code and the already defined debugger settings inside dape with some degree of success, I read the other answers and I read the gdb documentation about the dap interface, but to no avail. I must have miss something.

Using

• emacs 30.1
• arm-none-eabi-gdb 14.3 with python support
• openocd 0.12.0

What I tried

• Manually starting openocd and using only the .dir-locals lead to a gdb client not talking to openocd
• Manually starting openocd and using .gdbinit (so without :target and the other options inside .dir-locals) lead to a :initialize timeout triggered by dape (after around 15 seconds even if I set the timeout to 50 seconds)
• Using the configuration shared here (dape starts openocd and .gdbinit is used) it seems that dape doesn't start openocd correctly and gdb disconnect beause it can't find any server listening to the desired port.

Thank you in advance!

.dir-locals

;;; local directory variables -*- no-byte-compile: t -*-

((nil . ((dape-request-timeout . 50)))
 (nil . ((eval . (add-to-list
				  'dape-configs
				  `(gdb-openocd
				  ;; https://github.com/svaante/dape/discussions/238
				  fn (lambda (config)
					 (let* ((default-directory (dape--guess-root config))
						   (openocd
						 ;; Run openocd with config files from `openocd-files' property
						 (start-process-shell-command
						 "openocd" "*openocd*"
						 (concat "openocd"
								(mapconcat
								 (lambda (file)
								   (concat " -f " (shell-quote-argument file)))
								 (append (dape-config-get config 'openocd-files) nil)))))
						   probe)
					   ;; Wait until port is open
					   (while (and
							   (process-live-p openocd)
							   (not (setq probe
										  (ignore-errors
											(make-network-process
											 :name "openocd port probe"
											 :service 3333)))))
						 (sleep-for 0.1))
					   ;; Close probe connection
					  (when probe
					  (delete-process probe)))
					 config)
				  openocd-files ["interface/stlink.cfg"
							   "target/stm32u5x.cf"]
				  
				  modes (c-or-c++-mode c-ts-mode c++-ts-mode)
				  command-cwd dape-command-cwd
				  command "arm-none-eabi-gdb-py"
				  command-args ("--interpreter=dap")
				  compile "make build_debug"

				  :type "gdb"
				  :name "Launch debug"
				  :request "launch"
				  ;; For the debugger
				  ;; :args [""]
				  :cwd "./build"
				  ;; :env ""
				  :program "./Core/Src/firmware.elf"
				  :stopAtBeginningOfMainSubprogram t
				  :stopOnEntry t
				  :target "localhost:3333"
				  ))))))

.gdbinit

# Miscellaneous
set pagination off
set history save on
set history expansion on
#
file ./build/Core/Src/firmware.elf
#
target extended-remote localhost:3333
# 
set mem inaccessible-by-default off
# 
monitor reset halt
# 
load