How to get FSBL running on STM32MP151 over serial interface

[SJans.1]

Hi,

we are currently developing our own board using the STM32MP151 MPU.

Currently i am working on the FSBL in the non secure mode using U-boot.

I am able to generate a device tree with CubeMX, compile U-Boot and download it via STM32 Cube Programmer over UART4. After it seems to switch into the FSBL successfully the programmer can not contact the FSBL. I attached a log file and also my cube configuration.

I guess it would be helpfull to be able to debug the U-Boot. I know that the device tree should contain something like:

chosen {
		stdout-path = "serial0:115200n8";
	};
 
	aliases {
		serial0 = &uart7;
	};

But i can not seem to get CubeMX to generate that. Or is this one of the options i have to add manually? Or is there a more detailed guide how to debug the U-Boot?

I already read https://wiki.st.com/stm32mpu/wiki/U-Boot_-_How_to_debug

Thanks in advance

[Olivier GALLIEN · Accepted solution]

Hi @SJans.1​ 

You may know that STM32CubeMX generate a complete and fully fonctional dts for EV1 board project ... but not for 157C.

Please compare both generated dts for tf-a and note that quite all USER SECTION need to be filled

Olivier

[SJans.1]

Hi,

i can see that now. And i get the USER SECTION part now as well.

But even when i compile the stm32mp157c-157-eval-mx.dts file, generated from the cubemx i get the panic error.

Only when using the files from the developer package i can get the fsbl running. And i see that the dts files in that package are quite different.

In the example it does include files from quite some different dtsi files instead of having all in one place. Which makes it harder to follow through.

Stephan

[SJans.1]

Alright. I managed to get it running at least on the eval-board i guess.

I attached a log. Do you think this looks ok?

I will be moving back to my my custom board now and try to get a 151 config running over there.