How to compile the device tree with the Developer Package

1. Purpose

Information

We strongly advise to compile a device tree in a Linux® environment. The procedures described below are given as example, with limited support.

This article explains how to compile a device tree in a Windows^® environment, and how to deploy the compiled devicetree. Some steps require Windows^® bash, only available on Windows^® 10 version.

2. Rationale

STM32CubeMX can be used in both Linux^® and Windows^® environments.

The use of STM32MPU_Embedded_Software_distribution depends on a Linux^® environment.

Nevertheless, the generation of a device tree from STM32CubeMX and its compilation may be managed in a Windows^® environment for some components.

3. Pre-requisites

1. Install a cross-compiler
   • A cross compiler is needed to parse and prepare the device tree (.dts) file.

     System Workbench for STM32 is recommended.

     The zip file with the gcc can be found at <INSTALL_DIR>\plugins\fr.ac6.mcu.externaltools.arm-none.win32_1.16.0.201807130628\tools

     mingw64 is also a good alternative.

2. Install a device tree compiler
   • To install a community device tree compiler, please refer to Device Tree Compiler (MSYS2 version)
   • Upon request, STMicroelectronics may provide an executable binary, without warranty nor support.

4. Kernel device tree update

Information

Steps 1 and 2 have to be done in a Windows® 10 git bash session (patch is natively supported by git bash)

1. Get the Linux^® source code
2. Apply patches to the Linux^® source code
3. Create a workdir directory

   mkdir workdir

4. Copy from source code of Linux the dt-bindings and dt files

   cp <KernelSources>/include/dt-bindinds workdir

   cp <KernelSources>/arch/arm/boot/dts/* workdir/

5. Copy your dts into workdir

   cp <Your/dts/file.dts> workdir/

6. Prepare dts

   cd workdir

   arm-none-eabi-gcc.exe -E -nostdinc -I . -undef -D__DTS__ -x assembler-with-cpp -o <yourDTS.dts>.tmp <yourDTS.dts>

7. compile dts.tmp with dtc.exe

   dtc.exe -I dts -O dtb -o <DTBresult.dtb> <yourDTS.dts>.tmp

5. U-Boot device tree update

This operation depends on the use of a mkimage with stm32 support for Windows^® which is not officially available.

• The usage of a a cross-compiler for Windows^® and mingw64, the latest mkimage version (provided by U-Boot) will allow you to generate a mkimage version
• Upon request, STMicroelectronics may provide an executable binary, without warranty nor support.

6. TF-A device tree update

This operation is not supported. It is currently not possible to modify TF-A device tree without recompiling TF-A module.

Linux^® is a registered trademark of Linus Torvalds.

Device tree source (in software context) or digital temperature sensor (in peripheral context)

Das U-Boot -- the universal boot loader (see U-Boot)

Trusted firmware for Arm^® Cortex^®-A