STM32MP13 U-Boot

Applicable for

STM32MP13x lines

---

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

1. STM32MP13x lines  support

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

Also available in official U-Boot Git.

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 : generic STMicroelectronics board for STM32MP1 Series
• drivers/*/*stm32* : drivers

Configuration Files:

• defconfig file
  • configs/stm32mp13_defconfig
• config files
  • include/configs/stm32mp1.h
• STM32MP13_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

2. Selecting targets : choose defconfig and Device Tree

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 unknown board type identifier	stm32mp135f-dk	MB1635

3. Compilation

see U-Boot_overview#U-Boot_build

For STM32MP135F-DK unknown board type identifier , the device tree is already selected in defconfig stm32mp13_defconfig

 PC $> make stm32mp13_defconfig
 PC $> make all

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

 PC $> make stm32mp13_defconfig
 PC $> 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 ouput file, used to generated FIP, are u-boot-nodtb.bin and u-boot.dtb.

4. U-Boot integration in FIP

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 upddate of STM32MP135F-DK unknown board type identifier :

 PC $> fiptool --verbose update --nt-fw u-boot-nodtb.bin \
             --hw-config  u-boot.dtb \
             tf-a-fip-stm32mp135f-dk.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

5. Examples

5.1. STM32MP135F-DK unknown board type identifier

 PC $> make stm32mp13_defconfig
 PC $> make  all

or

 PC $> make stm32mp13_defconfig
 PC $> make DEVICE_TREE=stm32mp135f-dk all

and

 PC $> fiptool update --nt-fw u-boot-nodtb.bin \
             --hw-config  u-boot.dtb \
             tf-a-fip-stm32mp135f-dk.bin

5.2. STM32MP135F-DK unknown board type identifier with export

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

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

5.3. Custom board with external device tree

 PC $> make stm32mp13_defconfig
 PC $> make EXT_DTB=stm32mp131a-myboard.dtb all

 PC $> fiptool update --nt-fw u-boot-nodtb.bin \
             --hw-config  u-boot.dtb \
             tf-a-fip-stm32mp131a-myboard.bin

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

Arm^® is a registered trademark of Arm Limited (or its subsidiaries) in the US and/or elsewhere.

Cortex^®

Device tree binary (or Blob)

Firmware image package is a packaging format used by TF-A

Trusted firmware for Arm^® Cortex^®-A

Boot loader stage 3-3