.. _nxp-cm4-tool-setup:

Tools and BSP setup
===================

To compile the examples from the MCUXpresso SDK a tool chain for the Cortex®-M4/7 is needed.
Therefore, please read the chapter 'Install GCC Arm embedded tool chain' inside the document
'Getting Started with MCUXpresso SDK for EVK-MIMX8xx.pdf', which is provided by the SDK.
This documentation describes only tools setup under Linux.


installation of the GNU Toolchain
---------------------------------

To delop with the SDK, especially to build the SDK samples, a cross compiler toolchain is necessary. A ready to use
GNU Arm Embedded Toolchain can be downloaded from the
`arm developer web site <https://developer.arm.com/tools-and-software/open-source-software/developer-tools/gnu-toolchain/gnu-rm/downloads>`_.


The actual toolchain version at the moment is:

.. figure:: images/SDKXpresso-toolchain-july-2021.png
	:scale: 25 %
	:align: left
	:figwidth: 100%


There are toolchains for Windows, Linux or MacOS operating systems (32- or 64 bit).

For use with Linux Ubuntu OS hosts download and unpack the file: gcc-arm-none-eabi-10-2020-q4-major-x86_64-linux.tar.bz2

Create a new system environment variable with the name ARMGCC_DIR, that points to your Arm GCC Embedded tool chain installation path:

.. prompt::
   :prompts: $

   export ARMGCC_DIR=<path to your toolchain installation>/gcc-arm-none-eabi-10-2020-q4-major

Append your PATH environment variable with the folder to your tool chain's binaries:

.. prompt::
   :prompts: $

   export PATH=$PATH:<path to your toolchain installation>/gcc-arm-none-eabi-10-2020-q4-major/bin

check your installation by opening a new terminal window and type the command:

.. prompt::
   :prompts: $

   arm-none-eabi-gcc --version arm-none-eabi-gcc

.. code-block:: text

   (GNU Arm Embedded Toolchain 10-2020-q4-major) 10.2.1 20201103 (release)
   Copyright (C) 2020 Free Software Foundation, Inc.
   This is free software; see the source for copying conditions.  There is NO
   warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.


installation of CMake
---------------------

By default, the SDK is using CMake and not directly normal make files. If CMake is not installed by default in your Ubuntu distribution,
you can do that in the following way:

.. prompt::
   :prompts: $

   sudo apt install cmake


.. _imx-copro-install-short:

Customizing the BSP for coprocessor support
-------------------------------------------



To download and start the Cortex®-M4/7 firmware from the U-Boot, the U-Boot command **bootaux** must be implemented.
Also the Linux-kernel needs some features implemented to communicate between the main processors and the coprocessor.

To support customers, Ka-Ro provides the distro feature **copro**.
To add the distro feature to your build, go to your yocto build folder and open the file conf/bblayers.conf


then add the line:

.. code-block:: text

   DISTRO_FEATURES:append = " copro"


Furthermore, some special entries into the device tree are necessary. These are provided by the
devicetree overlay **karo-copro**

To add the karo-copro overlay, the name of the copro-overlay should be added to the appropriate overlays_* variable:


.. prompt::
   :prompts: U-Boot >

   setenv overlays_<baseboard> ${overlays_<baseboard>} karo-copro
   saveenv
   reset