STM32MP15 U-Boot

Applicable for

This article briefly describes the STM32MP15x lines support in U-Boot.

1. STM32MP15x lines support[edit | edit source]

For detailed information, read the file in the delivered U-Boot code = doc/board/st/stm32mp1.rst or the documentation generated by make htlmdocs: board/st/stm32mp1.html.

Code :

arch/arm/mach-stm32mp : arch specific code for STM32 Arm^® Cortex^® MPUs
- arch/arm/mach-stm32mp/Kconfig : generic configuration for STM32 Arm^® Cortex^® MPUs
- arch/arm/mach-stm32mp/Kconfig.15x : specific configuration for STM32MP15x lines
board/st/common : STMicroelectronics common code
board/st/stm32mp1 : STMicroelectronics boards support for STM32MP1 series
drivers/*/*stm32* : drivers

Configuration files:

defconfig file
- configs/stm32mp15_defconfig when FIP is used in OpenSTLinux
config files
- include/configs/stm32mp15_common.h : generic for STM32MP15x lines
- include/configs/stm32mp15_st_common.h : STMicroelectronics board for STM32MP15x lines
STM32_MPU_device_tree in arch/arm/dts : stm32mp15*.dts*
- <Device tree>.dts : same as kernel
- <Device tree>-u-boot.dtsi : addition for u-boot automatically included in build process
- stm32mp15-scmi-u-boot.dtsi : SoC add-on file included in <Device tree>-u-boot.dtsi
- stm32mp15-u-boot.dtsi : SoC add-on file for board support without SCMI, only for downstream support not used with OpenSTLinux

Warning

The U-Boot defconfig to use for ecosystem release ≥ v4.0.0 change to stm32mp15_defconfig.

The two next defconfig are kept only for compatibility with upstream, don't use them:

configs/stm32mp15_trusted_defconfig with stm32 image header support (CONFIG_STM32MP15x_STM32IMAGE)
configs/stm32mp15_basic_defconfig when SPL is used

2. Selecting targets : choose defconfig and device tree[edit | edit source]

The STM32 MPU boot chain is supported by one U-Boot configuration with defconfig = stm32mp15_defconfig

Several boards are supported with the associated device-tree (same name as kernel):

Board part number	Device tree	Description
STM32MP157A-EV1 Evaluation board	stm32mp157a-ev1	MB1262+MB1263
STM32MP157C-EV1 Evaluation board	stm32mp157c-ev1
STM32MP157D-EV1 Evaluation board	stm32mp157d-ev1
STM32MP157F-EV1 Evaluation board	stm32mp157f-ev1
STM32MP157A-DK1 Discovery kit	stm32mp157a-dk1	MB1272
STM32MP157D-DK1 Discovery kit	stm32mp157d-dk1	MB1272
STM32MP157C-DK2 Discovery kit	stm32mp157c-dk2	MB1272+MB1407
STM32MP157F-DK2 Discovery kit	stm32mp157f-dk2	MB1272+MB1407

For information the 'Evaluation' daughter-board only (MB1263 without MB1262) is also supported by stm32mp15*-ed1.dts device tree files.

3. Compilation[edit | edit source]

See U-Boot_overview#U-Boot_build with the defconfig file: stm32mp15_defconfig

  make stm32mp15_defconfig
  make DEVICE_TREE=<Device tree> all

The supported variables are:

DEVICE_TREE: select in arch/arm/dts the device tree that is used
KBUILD_OUTPUT: change the destination directory for the build
EXT_DTB: select external device tree

The output files u-boot.dtb and u-boot-nodtb.bin are integrated in FIP.

Note: All the compiled device trees are available in $KBUILD_OUTPUT/arch/arm/dts/*.dtb.
You can select them instead of u-boot.dtb without U-Boot recompilation.

4. U-Boot integration in FIP[edit | edit source]

U-Boot binary and its associated device tree are part of the FIP binary, created with TF-A Makefile option :

BL33_CFG = u-boot.dtb
BL33 = u-boot-nodtb.bin

or updated with fiptools:

--hw-config u-boot.dtb
--nt-fw u-boot-nodtb.bin

Example for FIP update :

  fiptool --verbose update --nt-fw u-boot-nodtb.bin \
             --hw-config  u-boot.dtb \
             fip-<board>.bin
 
 DEBUG: Replacing nt-fw with.../u-boot-nodtb.bin
 DEBUG: Replacing hw-config with .../u-boot.dtb
 DEBUG: Metadata size: ... bytes
 DEBUG: Payload size: ... bytes

See How_to_configure_TF-A_FIP for details.

5. Examples[edit | edit source]

5.1. STM32MP157F-EV1 Evaluation board [edit | edit source]

  make stm32mp15_defconfig
  make DEVICE_TREE=stm32mp157f-ev1 all

An existing FIP file is updated with:

  fiptool --verbose update --nt-fw u-boot-nodtb.bin --hw-config u-boot.dtb \
              fip-stm32mp157f-ev1.bin

5.2. STM32MP157C-EV1 Evaluation board [edit | edit source]

  make stm32mp15_defconfig
  make DEVICE_TREE=stm32mp157c-ev1 all

An existing FIP file is updated with:

  fiptool --verbose update --nt-fw u-boot-nodtb.bin --hw-config u-boot.dtb \
              fip-stm32mp157c-ev1.bin

5.3. STM32MP157D-DK1 Discovery kit [edit | edit source]

  make stm32mp15_defconfig
  make DEVICE_TREE=stm32mp157d-dk1 all

An existing FIP file is updated with:

  fiptool --verbose update --nt-fw u-boot-nodtb.bin --hw-config u-boot.dtb \
              fip-stm32mp157d-dk1.bin

5.4. STM32MP157C-DK2 Discovery kit [edit | edit source]

Using export to select the device tree

  export KBUILD_OUTPUT=../build/stm32mp15
  export DEVICE_TREE=stm32mp157c-dk2
  make stm32mp15_defconfig
  make all

An existing FIP file is updated with:

  fiptool --verbose update --nt-fw $KBUILD_OUTPUT/u-boot-nodtb.bin \
              --hw-config  $KBUILD_OUTPUT/u-boot.dtb \
              fip-stm32mp157c-dk2.bin

5.5. Custom board with external device tree[edit | edit source]

  make stm32mp15_defconfig
  make EXT_DTB=stm32mp151a-myboard.dtb all

Then you can create or update the FIP