The bitbang driver kept retrying a SWD command as long as
the debugged device had been responding by SWD WAIT.
If the DP stalled in WAIT permanently, OpenOCD hanged.
Check 0.5 sec timeout in WAIT retry loop.
While on it insert a short alive_sleep() if the command
is retried 20 or more times.
Signed-off-by: Tomas Vanek <vanekt@fbl.cz>
Change-Id: I744e56e21a5a2dc2c4494cc0d7bbcb4be14ddb23
Reviewed-on: https://review.openocd.org/c/openocd/+/8153
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>
Tested-by: jenkins
31af18e9d1