STM32MP135DAF – Custom Yocto Machine / eMMC Boot – PANIC and CubeProgrammer unable to Reconnect the Target device

[Midhul_Pk]

Hello,

I am working with an STM32MP135DAF on a custom board and am trying to boot OpenSTLinux/Yocto from eMMC.

My setup is:

MPU: STM32MP135DAF
Custom hardware/board
Custom Yocto machine
STM32CubeMX used to generate the Device Tree files
OpenSTLinux / Yocto
Boot device: MMC
Image: `core-image-minimal`

I have created a custom machine configuration and integrated the CubeMX-generated Device Tree files into my Yocto build.

The Yocto build completes successfully with:  “bitbake core-image-minimal”.

 

The image and flashlayout files are generated successfully.

However, when I try to program the board using STM32CubeProgrammer in USB DFU mode, CubeProgrammer reports that it cannot reconnect to the device.

I also connected a serial terminal to the debug UART. During the boot/programming sequence, I see:

PANIC at PC : 0x2ffe6405

Exception mode=0x00000016 at: 0x2ffe6405

The relevant CubeMX-generated DTS files, machine `.conf`, and `local.conf` are attached below.

Could someone please help me identify what could cause the: PANIC at PC : 0x2ffe6405
Exception mode=0x00000016. and why CubeProgrammer subsequently reports that it cannot reconnect?

Also, what would be the recommended procedure to debug this on a custom STM32MP135DAF + eMMC board?

Any suggestions or debugging steps would be greatly appreciated.

Thank you.

cube programmer error