npcx9m6f_evb: Instructions on how to flash board

Add instructions on how to flash blinky sample to this board using jlink
jtag programmer.

Signed-off-by: Jeremy Bettis <[email protected]>

Author: jeremybettis

boards/arm/npcx9m6f_evb/doc/index.rst

@@ -94,10 +94,32 @@ JTAG-only sessions.
 Flashing
 ========
 
-Build application as usual for the ``npcx9m6f_evb`` board, and flash
-using Servo V2, μServo, or Servo V4 (CCD). See the
+If the correct headers are installed, this board supports both J-TAG and also
+the ChromiumOS servo.
+
+To flash using Servo V2, μServo, or Servo V4 (CCD), see the
 `Chromium EC Flashing Documentation`_ for more information.
 
+To flash with J-TAG, install the drivers for your programmer, for example:
+SEGGER J-link's drivers are at https://www.segger.com/downloads/jlink/
+
+The openocd from Zephyr SDK 0.14.2 doesn't include npcx support, so build openocd from source.::
+
+  sudo apt-get install libftdi-dev libusb-1.0.0-dev
+  git clone https://git.code.sf.net/p/openocd/code ~/openocd
+  cd ~/openocd
+  ./bootstrap
+  ./configure --enable-jlink --enable-ftdi
+  make clean
+  make
+  sudo make install
+
+Build and flash the blinky sample.::
+
+  west build -t clean && \
+    west build -c -p auto -b npcx9m6f_evb samples/basic/blinky && \
+    west flash --hex-file build/zephyr/zephyr.npcx.hex \
+      --openocd /usr/local/bin/openocd --openocd-search /usr/local/share/openocd/scripts
 
 Debugging
 =========