Programming the FSBL to eMMC Flash

Hi gil_he

first what You need to do is unlock the partitions

echo 0 > /sys/class/block/mmcblk1boot0/force_ro

echo 0 > /sys/class/block/mmcblk1boot1/force_ro

and then type

dd if=USB/tf-a-stm32mp157f-ev1-emmc.stm32 of=/dev/mmcblk1boot0 conv=fdatasync

dd if=USB/tf-a-stm32mp157f-ev1-emmc.stm32 of=/dev/mmcblk1boot1 conv=fdatasync

If You want to do this from U-Boot it is necessary to use STM32 Cube Programmer to write the first and second-stage USB U-Boot and via debug UART stop U-Boot execution. Next in the stopped U-Boot console ums 0 mmc 0 or ums 0 mmc 1 and the memory will be visible from Your host computer.

So You can from the host do the same as above

dd if=USB/tf-a-stm32mp157f-ev1-emmc.stm32 of=/dev/mmcblk1boot0 conv=fdatasync

Of course, remember to align memory id ‘/dev/mmcblk1boot0‘

I hope to help You a little bit.

BR Michal

Thanks Michal for a great reply.

Gil,

If you have an eMMC on board, you will need a way to program it. Michal described 2 ways to do it and both of them require different interfaces to be active:

1. You can program the eMMC by booting from a secondary source like an SD card interface(this would also require you to change boot mode). From the Linux image booted from the SD card, you can program the eMMC by using “dd”

2. You can also program the eMMC via USB device port(like in OSD32MP1-BRK or OSD32MP1-RED). You will need to use Cube Programmer to USB boot

There is a 3rd way to boot which also involves using Cube Programmer, but only requires a UART via Serial boot. You can send FSBL(TF-A) and SSBL(U-Boot) via serial using Cube Programmer while you set the boot mode to serial. Then you can program the eMMC via a communication interface enabled by the SSBL, generally this is Ethernet, because you do not have USB/SD card interfaces as described in #1 or #2.

Please take a look at https://www.st.com/resource/en/application_note/an5275-usb-dfuusart-protocols-used-in-stm32mp1-series-bootloaders-stmicroelectronics.pdf and https://wiki.stmicroelectronics.cn/stm32mpu/wiki/How_to_use_UART_as_serial_boot_device_with_STM32CubeProgrammer for more info.

Best,

Neeraj