Cannot boot up custom board which based on STM32MP157C-DK2 , only get message from UART ..."PANIC at PC : 0x2ffdc323 , Exception mode=0x00000016 at: 0x2ffda000"

[fctu]

Hello,

We made a board that based on STM32MP157C-DK2.

First of all, show the configuration of our board as below....

(1). The major parts and circuit are same as DK2 such as DDR, PMIC, MicroSD, Ethernet.

(2). Some parts are removed such as MCU, WIFI/BT, HDMI Tx, USB hub, USB Type-C DRP and LCD module.

(3). And add some peripheral such as eMMC, two SPI devices (SPI4, SPI5), EEP (I2C-1)

The problem is: The board cannot boot up from SD card, list the symptoms as below...

(1). We tried to boot up the board by DK2 SD card (it works well on DK2), but got the exception message from UART ...

PANIC at PC : 0x2ffdc323

       Exception mode=0x00000016 at: 0x2ffda000

This is all messages since power on.

(2). The BOOT cfg. bit setting is confirmed on 101b, boot from SD card.

(3). The PA13 (boot status pin) kept Hi or Hi-Z.

(4). PMIC RANK-0 no power output, but other RANK had output power.

(5). About SD card access....

     a. Only SDMMC1_CK, SDMMC1_CMD and SDMMC1_D0 are works a few moment after power on.

  b. SDMMC1_D1~D2 did not work.

  c. I guess it works on 1-bit mode and then crashed.

   We guess it crashes on very early booting stage even still in ROM code.

Please advise you comments.

Many thanks.

FC.

[Olivier GALLIEN]

Hi @fctu​ 

This trace come from TF-A.

Even if your hardware looks to be very close, seems something prevent to use exact same TF-A of the DK2.

If not already done please cross check your TF-A device tree with help of these guideline :

https://wiki.st.com/stm32mpu/wiki/How_to_create_your_board_device_tree

https://wiki.st.com/stm32mpu/wiki/Clock_device_tree_configuration_-_Bootloader_specific

Olivier

[Olivier GALLIEN · Accepted solution]

For narrowing down further the issue, a so early error is typical from an HSE configuration issue.

Please refer to chapter 3.2.1.2 DT configuration for HSE in https://wiki.st.com/stm32mpu/wiki/Clock_device_tree_configuration_-_Bootloader_specific

Olivier

[fctu]

Hi OlivierG,

Thank you for your quick reply.

It is true that your magical suggestion is correct and has given us great help.

The external clock of our board is a crystal, and DK2 is an oscillator. After setting the TF-A DT clock correctly, our board can boot BL2 until U-Boot.

thank you for your help!

FC