This module provides the required STM32cube packages, dtsi files and libraries needed to build a Zephyr application running on STM32 silicon.

Packages, dtsi files and libraries are updated regularly in order for STM32 users to benefit from the latest STM32Cube versions, features and bug fixes. Updates are generally done once in each Zephyr release, preferably soon after the opening of the merge window to give time to users to use it, potentially report issues if some are faced and get them fixed before the new version in released.

STM32Cube packages

How to introduce a new version of stm32cube:

Original STM32Cube tree structure has been modified to a minimum structure for a better fit into Zephyr. STM32Cube is divided into drivers and soc section, with:

drivers/
    include/ contains Cube HAL/LL files from: Drivers/STM32YYxx_HAL_Driver/Inc/*
    src/ contains: Drivers/STM32YYxx_HAL_Driver/Src/*
soc/ contains STM32 CMSIS files from
    *Drivers/CMSIS/Device/ST/STM32F1xx/Include/*
    *Drivers/CMSIS/Device/ST/STM32F1xx/Source/Templates/system_stm32f1xx.c

Additionally driver/include/stm32f1xx_hal_conf_template.h is renamed into driver/include/stm32f1xx_hal_conf.h

If there are changes in the number of *.c files the Kconfig file in the stm32cube directory and the CMakeLists.txt files in the stm32yyxx/ directories will have to be updated. If *.c have been removed drivers that used them will also have to be updated.

IMPORTANT:

STM32Cube, as an external library, is not supposed to be modified. In practice, it might be required to patch it. When updating a STM32Cube package to a new version, please have a look to the patch list in dedicated README file, to make sure you don't overwrite some earlier modifications of the package. Furthermore, make sure to run the genllheaders.py script in order to make sure generic LL API headers are up-to-date. In case of doubt, contact Zephyr code owner for stm32cube.

How to use STM32Cube:

In order to enjoy ST CMSIS definitions, CONFIG_HAS_STM32CUBE should be defined and stm32yyxx.h should be included in soc.h

#include <stm32f1xx.h>

Additionally, in order to use STM32Cube LL, you should include the provided generic LL headers stm32_ll_foo.h directly in the file using the LL API:

#include <stm32_ll_usart.h>

Drivers and applications that need functions from the STM32Cube HAL/LL C-files will need to add the appropriate select entries in their Kconfig files. For example when functions from stm32f4xx_hal_uart.c are used, the following entry should apear in driver's Kconfig file.

select USE_STM32_HAL_UART

should be added to the Kconfig file.

And if the driver for example needs functions from the LL I2C C-files, the driver Kconfig file should include the following entry

select USE_STM32_LL_I2C

Similar to Zephyr, STM32Cube HAL and LL APIs embed asserts which are provided for parameters checking. You can benefit from these by enabling the following symbols:

CONFIG_USE_STM32_ASSERT=y
CONFIG_ASSERT=y

Use STM32Cube in your application:

It may happen that you want to access STM32Cube APIs in your application, either because it is not available as a zephyr API or because you want to by-pass use of existing Zephyr API. In this case, you need to create a Kconfig file in your application which contains the following:

mainmenu "MYAPP"

source "Kconfig.zephyr"
config MYAPP_STM32
  default y
  bool
  select USE_STM32_HAL_FOO
  select USE_STM32_LL_BAR

Additionally, you need to add the following includes:

#include <soc.h>
#include <stm32_ll_bar.h>

.dtsi files

In order to provide STM32 boards pin configuration using device tree, *-pinctrl.dtsi are made available under dts/st directory. For each STM32 SoC package a complete and correct -pcintrl.dtsi is available. Generation use as input the STM32 Open Pin Data database.

*-pinctrl.dtsi files are generated using generation scripts available in this repo under scripts/genpinctrl and can be generated by running:

python3 scripts/genpinctrl/genpinctrl.py -p /path/to/stm32-open-pin-data-repository

New set of -pinctrl.dtsi files could be generated following availability of a new version of STM32 Open Pin Data or a change in the generation script configuration files.

STM32Cube based libraries:

For some specific features, in order to benefit from already available and validated code. Libraries from STM32Cube packages are extracted and made available in this module under lib folder.

No script is available for these libraries, so update is done manually, but it should follow the same rhythm than STM32Cube packages.