Install Linux Host Dependencies

Documentation is available for these Linux distributions:

Ubuntu
Fedora
Clear Linux
Arch Linux

For distributions that are not based on rolling releases, some of the requirements and dependencies may not be met by your package manager. In that case please follow the additional instructions that are provided to find software from sources other than the package manager.

Note

If you’re working behind a corporate firewall, you’ll likely need to configure a proxy for accessing the internet, if you haven’t done so already. While some tools use the environment variables http_proxy and https_proxy to get their proxy settings, some use their own configuration files, most notably apt and git.

Update Your Operating System

Ensure your host system is up to date.

sudo apt-get update
sudo apt-get upgrade

sudo dnf upgrade

sudo swupd update

sudo pacman -Syu

Install Requirements and Dependencies

Note that both Ninja and Make are installed with these instructions; you only need one.

sudo apt-get install --no-install-recommends git cmake ninja-build gperf \
  ccache dfu-util device-tree-compiler wget \
  python3-dev python3-pip python3-setuptools python3-tk python3-wheel xz-utils file libpython3.8-dev \
  make gcc gcc-multilib g++-multilib libsdl2-dev libmagic1

sudo dnf group install "Development Tools" "C Development Tools and Libraries"
sudo dnf install git cmake ninja-build gperf ccache dfu-util dtc wget \
  python3-pip python3-tkinter xz file glibc-devel.i686 libstdc++-devel.i686 python38 \
  SDL2-devel

sudo swupd bundle-add c-basic dev-utils dfu-util dtc \
  os-core-dev python-basic python3-basic python3-tcl

The Clear Linux focus is on native performance and security and not cross-compilation. For that reason it uniquely exports by default to the environment of all users a list of compiler and linker flags. Zephyr’s CMake build system will either warn or fail because of these. To clear the C/C++ flags among these and fix the Zephyr build, run the following command as root then log out and back in:

echo 'unset CFLAGS CXXFLAGS' >> /etc/profile.d/unset_cflags.sh

Note this command unsets the C/C++ flags for all users on the system. Each Linux distribution has a unique, relatively complex and potentially evolving sequence of bash initialization files sourcing each other and Clear Linux is no exception. If you need a more flexible solution, start by looking at the logic in /usr/share/defaults/etc/profile.

sudo pacman -S git cmake ninja gperf ccache dfu-util dtc wget \
    python-pip python-setuptools python-wheel tk xz file make

CMake

A recent CMake version is required. Check what version you have by using cmake --version. If you have an older version, there are several ways of obtaining a more recent one:

On Ubuntu, you can follow the instructions for adding the kitware third-party apt repository to get an updated version of cmake using apt.
Download and install a packaged cmake from the CMake project site. (Note this won’t uninstall the previous version of cmake.)
```
cd ~
wget https://github.com/Kitware/CMake/releases/download/v3.21.1/cmake-3.21.1-Linux-x86_64.sh
chmod +x cmake-3.21.1-Linux-x86_64.sh
sudo ./cmake-3.21.1-Linux-x86_64.sh --skip-license --prefix=/usr/local
hash -r
```
The hash -r command may be necessary if the installation script put cmake into a new location on your PATH.

Download and install from the pre-built binaries provided by the CMake project itself in the CMake Downloads page. For example, to install version 3.21.1 in ~/bin/cmake:

mkdir $HOME/bin/cmake && cd $HOME/bin/cmake
wget https://github.com/Kitware/CMake/releases/download/v3.21.1/cmake-3.21.1-Linux-x86_64.sh
yes | sh cmake-3.21.1-Linux-x86_64.sh | cat
echo "export PATH=$PWD/cmake-3.21.1-Linux-x86_64/bin:\$PATH" >> $HOME/.zephyrrc

Use pip3:
```
pip3 install --user cmake
```
Note this won’t uninstall the previous version of cmake and will install the new cmake into your ~/.local/bin folder so you’ll need to add ~/.local/bin to your PATH. (See Python and pip for details.)
Check your distribution’s beta or unstable release package library for an update.
On Ubuntu you can also use snap to get the latest version available:
```
sudo snap install cmake
```

After updating cmake, verify that the newly installed cmake is found using cmake --version. You might also want to uninstall the CMake provided by your package manager to avoid conflicts. (Use whereis cmake to find other installed versions.)

DTC (Device Tree Compiler)

A recent DTC version is required. Check what version you have by using dtc --version. If you have an older version, either install a more recent one by building from source, or use the one that is bundled in the Zephyr SDK by installing it.

Python

A modern Python 3 version is required. Check what version you have by using python3 --version.

If you have an older version, you will need to install a more recent Python 3. You can build from source, or use a backport from your distribution’s package manager channels if one is available. Isolating this Python in a virtual environment is recommended to avoid interfering with your system Python.

Install the Zephyr Software Development Kit (SDK)

The Zephyr Software Development Kit (SDK) contains toolchains for each of Zephyr’s supported architectures. It also includes additional host tools, such as custom QEMU and OpenOCD.

Use of the Zephyr SDK is highly recommended and may even be required under certain conditions (for example, running tests in QEMU for some architectures).

The Zephyr SDK supports the following target architectures:

ARC (32-bit and 64-bit; ARCv1, ARCv2, ARCv3)
ARM (32-bit and 64-bit; ARMv6, ARMv7, ARMv8; A/R/M Profiles)
MIPS (32-bit and 64-bit)
Nios II
RISC-V (32-bit and 64-bit; RV32I, RV32E, RV64I)
x86 (32-bit and 64-bit)
Xtensa

Follow these steps to install the Zephyr SDK:

Download and verify the latest Zephyr SDK bundle:
```
wget https://github.com/zephyrproject-rtos/sdk-ng/releases/download/v0.15.2/zephyr-sdk-0.15.2_linux-x86_64.tar.gz
wget -O - https://github.com/zephyrproject-rtos/sdk-ng/releases/download/v0.15.2/sha256.sum | shasum --check --ignore-missing
```
You can change 0.15.2 to another version if needed; the Zephyr SDK Releases page contains all available SDK releases.

If your host architecture is 64-bit ARM (for example, Raspberry Pi), replace x86_64 with aarch64 in order to download the 64-bit ARM Linux SDK.

Extract the Zephyr SDK bundle archive:

cd <sdk download directory>
tar xvf zephyr-sdk-0.15.2_linux-x86_64.tar.gz

Run the Zephyr SDK bundle setup script:
```
cd zephyr-sdk-0.15.2
./setup.sh
```
If this fails, make sure Zephyr’s dependencies were installed as described in Install Requirements and Dependencies.

If you want to uninstall the SDK, remove the directory where you installed it. If you relocate the SDK directory, you need to re-run the setup script.

Note

It is recommended to extract the Zephyr SDK bundle at one of the following locations:

$HOME
$HOME/.local
$HOME/.local/opt
$HOME/bin
/opt
/usr/local

The Zephyr SDK bundle archive contains the zephyr-sdk-0.15.2 directory and, when extracted under $HOME, the resulting installation path will be $HOME/zephyr-sdk-0.15.2.

If you install the Zephyr SDK outside any of these locations, you must register the Zephyr SDK in the CMake package registry by running the setup script, or set ZEPHYR_SDK_INSTALL_DIR to point to the Zephyr SDK installation directory.

You can also use ZEPHYR_SDK_INSTALL_DIR for pointing to a directory containing multiple Zephyr SDKs, allowing for automatic toolchain selection. For example, ZEPHYR_SDK_INSTALL_DIR=/company/tools, where the company/tools folder contains the following subfolders:

/company/tools/zephyr-sdk-0.13.2
/company/tools/zephyr-sdk-a.b.c
/company/tools/zephyr-sdk-x.y.z

This allows the Zephyr build system to choose the correct version of the SDK, while allowing multiple Zephyr SDKs to be grouped together at a specific path.

Building on Linux without the Zephyr SDK

The Zephyr SDK is provided for convenience and ease of use. It provides toolchains for all Zephyr target architectures, and does not require any extra flags when building applications or running tests. In addition to cross-compilers, the Zephyr SDK also provides prebuilt host tools. It is, however, possible to build without the SDK’s toolchain by using another toolchain as as described in the Toolchains section.

As already noted above, the SDK also includes prebuilt host tools. To use the SDK’s prebuilt host tools with a toolchain from another source, you must set the ZEPHYR_SDK_INSTALL_DIR environment variable to the Zephyr SDK installation directory. To build without the Zephyr SDK’s prebuilt host tools, the ZEPHYR_SDK_INSTALL_DIR environment variable must be unset.

To make sure this variable is unset, run:

unset ZEPHYR_SDK_INSTALL_DIR