I would like to run linux on cortex-M MCU in Stm32mp157-EV but i don't know what's wrong?

[Fheid.1]

Hi

dear engineers,

i can run linux on stm32f429 mcu without any problem, but it failed on Cortex-M MCU in stm32mp157 board.

After many hours i realize:

error happens in below function

void __meminit __free_pages_bootmem...

Anyone else had a similar problem? how you resolved it?

Shall i change any register address in kernel? (i think every thing is the same in cortex-M4 and stm32f429).

Best regards

[Olivier GALLIEN]

Hi @Fheid.1​ 

I supposed you mention STM32F429IDISCO for F4 platform supporting Linux ?

It has 2MB flash while you only have a budget of 384KB of MCU RAM in STM32MP1.

Did you shape your linux system to fit in this space ?

Olivier

[Fheid.1]

Hi dear @Community member​ 

Thanks for your attention:bouquet:

Yes you supposed right, I know running linux on cortex M is unusual project.

I have taken the first steps of the project and I hope to do it successfully with your help.

You know better than me the electronic circuit and the structure of stm32mp157,

 I use 64 kB and three 128 kB memory in addition to DDR3 for running linux. It is so complex but I can explain it step by step if you want.

After too many ties i can access the attachment picture, Could you understand my recent status using sending image?

Could you help me?

Kind regards

[Olivier GALLIEN]

Hi @Fheid.1​ 

>> I use 64 kB and three 128 kB memory in addition to DDR3 for running linux

Are you aware that on STM32MP15x, Cortex-M4 is not intended to access DDR content. Cortex-M4 has no cache and asynchronous path to AXI bus has not been optimized for that, so Cortex-M4 performance will be very largely impacted.

I also presume you are running "engineering" mode where DDR3 is not available, since not powered nor configured.

Olivier

[Fheid.1]

Hi Mr @Community member​ 

Thank you indeed.

I am running "production" mode and accessing DDR3 is available for me.

Im not worried a bout performance or running speed.

according to RM0436 datasheet i can access to DDR content without any problem.

i have done the following settings on Cortex-A and Cortex-M. please check attached file...

if it is hardly readable tell me to send each of them separately.

[Fheid.1]

i mentioned it:backhand_index_pointing_down: :

"error happens in below function

void __meminit __free_pages_bootmem..."

i dont know any thing a bout mentioned function. Does that function error occur in a particular situation?