DDR Bus Test Error in STM32MP157AAD3 before FSBL, How to resolve this?

[BG.3]

Our board is similar to STM32MP157C-DK2 Disco board - All the Developer packages have been installed, When the power supply is given, all the test point voltages are in desired level. But the MPU not even clearing FSBL and exit with

ERROR: DDR addr bus test: can't access memory @ 0xc0000004

PANIC at PC : 0x2ffdf9d9

Exception mode=0x00000016 at: 0x2ffda000

What is the issue and how we can address?

[PatrickF]

Hi,

There is many FAQ which could help:

from this page : https://community.st.com/s/article/FAQ-STM32MP1-Bring-up-procedure you could find many links/information.

Regards.

[BG.3]

Thank you so much for responding. I'll look into it.

[DG_it]

Hello, have you solved the problem? I have encountered a similar problem.

[PatrickF]

Hi,

error message is usually just not enough to help.

We need more information on your setup (HW, SW, board, etc...) and the check you already done (supplies, soldering, etc...).
For DDR, even if slightly outdated, this page could help to go further

https://community.st.com/t5/stm32-mpus/faq-stm32mp1-how-to-validate-the-stm32mp1-dram-connection-on-pcb/ta-p/49270

Community is not a simple question/answer tool, but a sharing platform intended to raise knowledge and allows people to find themself the solution or the path for deeper investigation.

Regards.

[asadullah4571]

I think the ISSUE with the PMIC it won't supply the voltage to the ddr.
I Read the datasheet of PMIC i Found that my DDR is connected to PMIC buck 2 which is RANK 0.
i do not know anything of that. 
who are RANK 0 in PMIC are not supplied the power.
so where i need to modify and TF-A then it work.

[PatrickF]

Hi,

It is normal to have DDR supplies as RANK0 (not powered by default).

The DDR supplies are started in right sequence by the TF-A SW. There is no need to modify SW, but maybe you have issue on your Device Tree regarding DDR related supplies definitions.

If your HW around STPMIC1 and DDR3L is same than STM32MP157D-DK2, please look to the related TF-A DT which could help you to align your own DT: https://github.com/STMicroelectronics/arm-trusted-firmware/blob/v2.8-stm32mp/fdts/stm32mp15xx-dkx.dtsi (some other DT files might be involved as well)

Regards.