Issues with Buildroot on STM32MP157C Eval board

Hello, I am evaluating the use of your SOM for the STM32MP157C for a project but am having issues getting a custom image made with buildroot to run on your eval board.

When I power up the board with my custom image, the board seems to have an issue with i2c not being able to talk to the PMIC, see below for the full output. I built an image for the official STM32MP157c-dk2 as I have some of those kits as well and looking at the boot output your eval board is treated as one by u-boot, so I don’t see any major hardware differences. Are you using a custom device tree?

U-Boot SPL 2018.11-stm32mp-r2.2 (Aug 20 2020 - 10:56:42 -0400)
Model: STMicroelectronics STM32MP157C-DK2 Discovery Board
RAM: DDR3-1066/888 bin G 1x4Gb 533MHz v1.44
stpmic1_read: failed to read register 0x27 : -110ddr power init failed

The only other difference I could spot was that there seemed to be a custom u-boot branch used by the seeed wiki image, I am using the “2018.11-stm32mp-r2.2” branch from the stm u-boot repo while the wiki image uses “U-Boot SPL 2018.11-stm32mp-r2.2-00047-g1dfe5d6799-dirty”.

Any ideas as to how to get the board running would be greatly appreciated!

We haven’t used buildroot. Sorry, we can’t help you.

Even i am facing the same issue. But looks like the response is so detailed then i am not able to understand through that as well.
3 Cheers for Seeed Support Forum.

Try this if you can use TF-A instead of U-Boot SPL: