IAR Arm Toolchain

Download and install a release of IAR Arm Toolchain (EWARM/CXARM) on your host.

Note

As of now, a Development version of the IAR build tools for Arm is required to work with Zephyr. It is distributed to selected partners and customers for evaluation. If you are interested in being part of this program, please send a request to the IAR FAE team at fae.emea@iar.com.

Make sure you have Zephyr SDK installed on your host.

Note

A Zephyr SDK is used as a source of tools like device tree compiler (DTC), QEMU, etc… Even though IAR Arm toolchain is used for Zephyr RTOS build, still the GNU preprocessor & GNU objcopy might be used for some steps like device tree preprocessing and .bin file generation.

Set these environment variables:
- Set ZEPHYR_TOOLCHAIN_VARIANT to iar.
- Set IAR_TOOLCHAIN_PATH to the toolchain installation directory.
The IAR Toolchain needs the IAR_LMS_BEARER_TOKEN environment variable to be set to a valid license bearer token.

For example:

# Linux (default installation path):
export IAR_TOOLCHAIN_PATH=/opt/iarsystems/bxarm/arm
export ZEPHYR_TOOLCHAIN_VARIANT=iar
export IAR_LMS_BEARER_TOKEN="<BEARER-TOKEN>"

# Windows:
set IAR_TOOLCHAIN_PATH=c:\<path>\arm
set ZEPHYR_TOOLCHAIN_VARIANT=iar
set IAR_LMS_BEARER_TOKEN="<BEARER-TOKEN>"

Note

The IAR Toolchain uses ilink for linking. This is incompatible with Zephyr’s linker script template, which works with GNU ld. Zephyr’s IAR Arm Toolchain depends on Zephyr’s CMake linker script generator, which supports generating icf-files. Basic icf-file support is in place, but there are still areas which are not fully supported by the CMake linker script generator.

Note

The IAR Toolchain uses the GNU Assembler which is distributed with the Zephyr SDK for .S-files.

Note

Some Zephyr subsystems or modules may also contain C or assembly code that relies on GNU intrinsics and have not yet been updated to work fully with iar.