DDR addr bus test Error in STM32MP153A

[DG]

We modified the device tree file corresponding to our development board based on stm32mp157d-ev1.dts.We did not use a PMIC chip, so we added our own power node and modified the default serial port output.This is my device tree file:The following errors will occur during the burning process：

[PatrickF]

Hi,

The message is quite clear, the DDR cannot be accessed.

First check (again) that your HW is correct (MP25 and DDR supplies, signals mixed-up, references, ZQ, etc...). Maybe share some portion of schematics here for different eyes check.

You could also check DDR interface using https://wiki.st.com/stm32mpu/wiki/STM32DDRFW-UTIL (need to be tailored to our board, especially as you don't use STPMIC1).

maybe have a look to https://community.st.com/s/article/FAQ-STM32MP1-Bring-up-procedure

Regards

[DG]

This is my DDR related circuit,the ddr is powered by a ddr voltage regulator.please take a look. Is there any problem?

[PatrickF]

22 ohms terminations to VTT are likely too low. We recommend 56 ohms.

Maybe not the root cause, but decoupling is light on xxuF range capacitors. e.g. VTT_DDR is maybe missing one or two 10-22uF capacitor close to the memory.

Maybe not an issue, but terminations on DDR_A15 and DDR_CKE are missing.

I did not check the LTM4632 wirings, I assume you have check correct (and not noisy) voltages on VCC_DDR (1.35V or 1.5V) and VTT_DDR/VREF_DDR (VCC_DDR/2).

Regards.