Programming on board eMMC using Cube Programmer

[NGajic]

Hi,

We have a custom board with onboard eMMC which is connected on SDMMC2 lines:

SDMMC2_D0 - PB14

SDMMC2_D1 - PB15

SDMMC2_D2 - PB3

SDMMC2_D3 - PB4

SDMMC2_D4 - PB8

SDMMC2_D5 - PB9

SDMMC2_D6 - PC6

SDMMC2_D7 - PC7

SDMMC2_CMD - PG6

SDMMC2_CLK - PE3

These pins are not all default pins for SDMMC2 so I'm interested if there is a way to program this eMMC using DFU mode with Cube Programmer. Is there a way to change pins which are used for programming?

Best regards,

Nenad

[Fee]

Hi,

with CubeProgrammer and its DFU mode you will need to have a running TF-A and U-Boot. In those you can customize each device tree in order to get the sdmmc2 peripheral working with your pins (by defining your pins with a pinctrl). TF-A and U-Boot will then be able to detect your eMMC. You might have a look at these links:

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

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

I can recommend using CubeMX to define your sdmmc2 pin configuration for the device tree.

[NGajic]

Thank you very much @Lukas Brückner​. Everything is clear now.

Best regards,

Nenad

[PatrickF]

Hello,

After the TF-A and uBoot customization as stated by @Lukas Brückner​, you should suceed to program the eMMC. Then in order to allow the BootROM to use your non-default pin for eMMC on SDMMC2, you also need to setup some OTP.

See an example on https://community.st.com/s/question/0D53W00000PoivmSAB/changing-the-emmc-pins-with-otp for instance

See also https://wiki.st.com/stm32mpu/wiki/STM32MP15_ROM_code_overview#Boot_from_e-E2-80-A2MMC-E2-84-A2

Regards.

[NGajic]

Hi @PatrickF​ ,

I'm using those 3 pins for SDMMC2 and BootROM would use them by default.

SDMMC2_D0 - PB14

SDMMC2_CMD - PG6

SDMMC2_CLK - PE3

Do I need to change OTP, maybe no?

I wanted to say that my other pins (D4-D7) are not default for SDMMC2 (picture below). Are these SDMMC2 pins set with subsequent device tree-s (tf-a, u-boot, kernel dtb)?

Thanks in advance,

Nenad

[PatrickF]

Sorry, I misread your first post.

In that case, no need to program OTP, just define the pins in Device Tree for TF-A, uBoot and Linux.

Regards.