Regarding STM32mp157A UART in U BOOT

[Sindhu Vadde]

Hi,

We are using stm32mp157a processor and we are working on uboot-v2018.11 at Linux side. I have an idea on board-debug-uart_init().

Path for board_debug_uart_init().

Path :board/st/stm32mp1/board.c

In board-debug-uart_init() .We have only UART_TX information i.e They configured only UART_TX pin in board_debug_uart_init() function.I need to know where will we configure UART_RX pin.

Refer the below link for uboot-v2018.11 source code Analysis.

https://elixir.bootlin.com/u-boot/v2018.11/source

[Kevin HUBER · Accepted solution]

Hi @Sindhu Vadde​ ,

I don't know if you still need an answer, but this function board_debug_uart_init() is used for debugging the u-boot.

So since there is only debug traces on this port, only the UART_TX is needed.

You can find information about the debug of U-Boot in this page:

https://wiki.st.com/stm32mpu/wiki/U-Boot_-_How_to_debug#Debug_with_console

Remember that you have to adapt the function board_debug_uart_init(): that configures the required resources (pad, clock) before initialization by the U-Boot driver.

This function needs to be adapted for your board.

Regards,

Kévin