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Visitor II
July 25, 2025
Question

forced_mode of boot_ctx is always set to 3

  • July 25, 2025
  • 1 reply
  • 531 views

Hello ST team,

I came across issue here.

The force_mode of boot_ctx is always set to 3, which force the MPU to boot over USB, rather than MMC. I tried to set TAMP_BKP20R(BOOT MODE) to 0, but the behavior is the same after reset.

ISSUE MPU.png

Aslo, I have another board (hardware is slightly different, but boot pin configuration is the same), which works well.

GOOD MPU.png

I know it can be fixed by changing UBOOT code. My questions are:

1. Is the value of this register boot_ctx set by ROM code?

2. The MPU model and version of the above two board are the same, STM32MP151FAD Rev.Z. Why is their behavoir different? 

    This topic has been closed for replies.

    1 reply

    Technical Moderator
    August 8, 2025

    Hi @fantasylsdo 

    One assumption to check 

    May you properly delete the configuration of USER1 button in you DT ? 

    See description in LEDs and buttons on STM32 MPU boards - stm32mpu 

    Hope it help 

    Olivier 

     

    Visitor II
    August 25, 2025

    Hello Olivier,

    Thanks for your reply. USER1 button is already deleted in our curret DT. It still doesn't work.

     

    Regards,

    fantasylsdo