Question, i.MX8M serial debug console ports.

[SLICE]

Dear team,

I would like to ask about serial debug message output ports of i.MX8M.

Is it possible to change the debug ports to other ports than used on your EVK board?

If an internal boot rom of i.MX8M uses the ports, please let me know.

Thanks,

Miyamoto

[igorpadykov]

Hi Miyamoto

could you clarify what do you mean by "change the debug ports", if this uboot, linux or smth else.

In uboot one can look at #define CONFIG_MXC_UART in

uboot/include/configs/imx8mq_evk.h

imx8mq_evk.h\configs\include - uboot-imx - i.MX U-Boot 

In linux using console kernel parameter as described in

Table 10. Common kernel boot parameters attached Release Notes.

check for  "&uart1 { /* console */" ..
in linux dts file : linux/arch/arm64/boot/dts/freescale/fsl-imx8mq-evk.dts

fsl-imx8mq-evk.dts\freescale\dts\boot\arm64\arch - linux-imx - i.MX Linux kernel 

ROM does not use uart.

Best regards
igor
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[SLICE]

Hello Igor,

The customer thinks that if iROM uses serial port for debugging, there might be problem when they change the debug port. And you said iROM does not use it.

So, I will inform the customer that one can change the port in their software including u-boot or linux implementation.

Thanks,

Miyamoto

[igorpadykov]

Hi Miyamoto

iROM does not use serial port for debugging.

Best regards
igor

[george]

Dear igorpadykov‌

In my understanding, u-boot for i.MX8MQ-EVK uses Device-Tree as default.

Is the change to the device-tree unnecessary like kernel?

fsl-imx8mq-evk.dts\dts\arm\arch - uboot-imx - i.MX U-Boot 

Best Regards,

Fukutomi

[igorpadykov]

Hi Fukutomi

this is general uboot question, suggest to post on uboot mail list. In particular it is discussed on many forums, like

arm - Why Device Tree Structure (DTS) file is needed both in bootloader and kernel source code? - St... 

Best regards
igor