While stlink v2 anly accept till to 2 MHz for SWV baudrate, stlink v3 accepts up to 24 MHz. Check the stlink version and use the respective max value. Change-Id: I911207a35983b6acf0b901059076dd31f70e6290 Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com> Reported-by: Pawel <phryniszak@users.sourceforge.net> Fixes: https://sourceforge.net/p/openocd/tickets/283/ Reviewed-on: http://openocd.zylin.com/5908 Tested-by: jenkins