STM32MP157AAA can not boot

[Ssun.21]

Hello,

PLEASE GIVE SOME HELP.

We made some boards based on MP157AAA and it ran good at first.

BUT it can not boot anymore after someone turn off and on the power.

No information comes from UART4 after turn on power switch.

I change the boot-switch to '000' and use "cube programmmer " to update boot.

some information comes out form uart4 but "cube programmmer " show error.

SO,please tell me how to update boot-part or our hardware has been damaged Permanently.

Thanks a lot.

SIMON.

[PatrickF]

If a power off/on burn something, it could be related to supplies, maybe check the DDR supplies (which is required by uBoot).

Otherwise, your SW config might need some tuning, may I suggest to read those FAQ:

https://community.st.com/s/article/FAQ-STM32MP1-STM32CubeProgrammer-USB-reconnect-error-at-STM32MP1-boot-device-flashing

https://community.st.com/s/article/FAQ-STM32MP1-How-to-create-a-device-tree-with-STM32CubeMx-for-your-design

https://community.st.com/s/article/FAQ-STM32MP1-Bring-up-procedure

also one common pitfall when building your own board is around HSE settings. The BootROM has automatic HSE detection (oscillator or crystal) whereas this setting is fixed in device tree (thus making uBoot stopping to work as it could killing its clock). Our board are using digital bypass with external oscillator (and so our default DT).

please have a look to https://wiki.st.com/stm32mpu/wiki/Clock_device_tree_configuration_-_Bootloader_specific#DT_configuration_for_HSE

[Ssun.21]

Dear PatrickF,

Thanks for your answer.

We have solved this issue.

We use a Bootable TF-card to re-flash system.

Then, it can boot from eMMC.

This is really weird。

we found that Solder-tool do not have a good ground may cause this issue.

Because we can duplicate this issue by soldering it.

--------Simon.