STM32MP13 U-Boot

Applicable for

This article briefly describes the STM32MP13x lines support in U-Boot.

1. STM32MP13x 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.13x : specific configuration for STM32MP13x lines
board/st/common : STMicroelectronics common code
board/st/stm32mp1 : STMicroelectronics boards support for STM32MP1 series
drivers/*/*stm32* : drivers

Configuration files:

defconfig file
- configs/stm32mp13_defconfig
config files
- include/configs/stm32mp13_common.h : generic for STM32MP13x lines
- include/configs/stm32mp13_st_common.h : STMicroelectronics board for STM32MP13x lines
STM32_MPU_device_tree in arch/arm/dts : stm32mp13*.dts*
- <Device tree>.dts: same as kernel
- <Device tree>-u-boot.dtsi: addition for u-boot automatically included in build process
- stm32mp13-u-boot.dtsi : SoC add-on file included in <Device tree>-u-boot.dtsi

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

The U-Boot configuration with defconfig is stm32mp13_defconfig.

The STM32MP13 boards are supported with the associated device tree (same name as kernel):

Board part number	Device tree	Description
STM32MP135F-DK Discovery kit	stm32mp135f-dk	MB1635

3. Compilation[edit | edit source]

see U-Boot_overview#U-Boot_build

For STM32MP135F-DK Discovery kit , the device tree is already selected in defconfig stm32mp13_defconfig

 make stm32mp13_defconfig
 make all

For other boards, you need to select the correct device tree

 make stm32mp13_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.
EXT_DTS: select PATH of external device tree source, by default the sub-directory "arch/arm/dts/external-dt" is used to allow sub-module.

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

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

4. Examples[edit | edit source]

4.1. STM32MP135F-DK Discovery kit [edit | edit source]

 make stm32mp13_defconfig
 make  all

or

 make stm32mp13_defconfig
 make DEVICE_TREE=stm32mp135f-dk all

and

 fiptool --verbose update --nt-fw u-boot-nodtb.bin  --hw-config u-boot.dtb \
                        fip-stm32mp135f-dk.bin

4.2. STM32MP135F-DK Discovery kit with export[edit | edit source]

 export KBUILD_OUTPUT=../build/stm32mp13
 export DEVICE_TREE=stm32mp135f-dk
 make stm32mp13_defconfig
 make all

 fiptool --verbose update --nt-fw $KBUILD_OUTPUT/u-boot-nodtb.bin \
             --hw-config  $KBUILD_OUTPUT/u-boot.dtb \
             fip-stm32mp135f-dk.bin

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

 make stm32mp13_defconfig
 make EXT_DTB=stm32mp131a-myboard.dtb all

 fiptool --verbose update --nt-fw u-boot-nodtb.bin \
             --hw-config  u-boot.dtb \
             fip-stm32mp131a-myboard.bin