topic Re: Debug methods - IMX8QXP in i.MX Processors

Debug methods - IMX8QXP

jnj — Fri, 09 Feb 2024 13:41:21 GMT

Hi All,

I am currently working on IMX8QXP-MEK, and I have some queries regarding the debugging methods. I am a newbie to this platform. From the NXP documents, I came to know that there are mainly two methods to debug i.MX8. One is UART, and the second one is JTAG.

When the EVK is connected to the PC via USB, there are 4 UART ports visible: /dev/ttyUSB0, /dev/ttyUSB1, /dev/ttyUSB2, and /dev/ttyUSB3. Cortex A35 prints [Linux] can be seen over /dev/ttyUSB0, and M4 Cortex prints can be seen over /dev/ttyUSB2.

I am a little bit confused about which UART (among FTDIA, FTD_IB, FTDIC, FTDID ) is connected to Cortex A35 and Cortex M4 debugging.UART Connection diagram of EVK is shown below.an JTAG be used for debugging both M4 and A35? Or can M4 only be debugged using JTAG? Kindly help me to resolve my doubts.

Thanks in advance !

Re: Debug methods - IMX8QXP

Chavira — Fri, 09 Feb 2024 18:06:18 GMT

Hi @jnj!
Thank you for contacting NXP Support!

You can see 4 ports when you connect the board to your board because the UART to USB bridge supports 4 ports (only 3 are connected to the board).

By default using our bsp and examples the cores can be debugged as you mention "Cortex A35 prints [Linux] can be seen over /dev/ttyUSB0, and M4 Cortex prints can be seen over /dev/ttyUSB2" but in really you can use any uart for each core, but I recommend to use the default configuration because the changes and configurations to change the debug uart port are a little difficult.

The JTAG connector can be used to debug both cores normally we debug only the M core with the JTAG connector, but using tools like Lauterbach you can debug any core on the chip.

Best Regards!
Chavira

Re: Debug methods - IMX8QXP

jnj — Sat, 10 Feb 2024 01:54:39 GMT

Hi @Chavira ,

Thank you for the response. Is there any Document to refer for debugging a35 cortex using debugging tool? Similarly among FTDIA, FTD_IB, FTDIC, FTDID in the schematics which Uart is connected to cortex a35 and cortex m4?

Re: Debug methods - IMX8QXP

Chavira — Tue, 13 Feb 2024 02:40:18 GMT

Hi @jnj!

For iMX8QXP the M and A Core have their peripherals.

In the schematic, you can see the connections between the FTDI and the iMX.

Check the Reference Manual in chapter 9 "Pin Assignment" and you can see the Peripherals for the M core and the A core.

The A core is debugged for the UART0 (Connected to FDTIA) and the M core is debugged on M40_UART0 (UART 0 for M core and connected to FTDIC), the UART3 is connected to FTDIB.

Sorry for the mistake!

Best Regards!
Chavira

Re: Debug methods - IMX8QXP

jnj — Tue, 13 Feb 2024 06:29:07 GMT

Hi @Chavira ,

Thank you so much for the confirmation. I attempted to debug the Cortex-M4 using an MCUXpresso SDK demo, specifically the 'hello world' application. I connected the Segger J-Link and utilized the JLinkGDBserver and client. Successfully, I could observe the 'hello world' prints over /dev/ttyUSB2. However, the binary for the Cortex-M4 is not being updated. After rebooting, I am encountering the following prints over /dev/ttyUSB2.I have followed mcuxpresso sdk guide.

Is it possible to update the M4 demo bin in emmc using the Jlink? Is there any Document to refer for debugging a35 cortex using debugging tool?

Re: Debug methods - IMX8QXP

Chavira — Wed, 14 Feb 2024 13:12:18 GMT

Hi!
Thank you for contacting NXP Support!

You have to flash your binary on the fat partition of the MMC.

Please check our "getting started" of the board to see the instructions for that.

You can use the uuu tool to update the fat partition of the board too.

You can flash only the m4.bin using the command below:

under u-boot use the command "fastboot 0", and connect the OTG port to the host.

uuu -b fat_write <m4.bin> mmc <device>:<particion> <name_on_board.bin>

https://www.nxp.com/document/guide/getting-started-with-the-mcimx8qxp-cpu:GS-MCIMX8QXP-CPU?section=mcuxpresso-sdk

Best Regards!

Chavira

Re: Debug methods - IMX8QXP

jnj — Wed, 14 Feb 2024 13:35:19 GMT

Hi @Chavira ,

Thank you for the response. Could you please elaborate this method of flashing only the hello_world.bin:

uuu -b fat_write <m4.bin> mmc <device>:<particion> <name_on_board.bin>

In which document can we find this ?

Re: Debug methods - IMX8QXP

Chavira — Wed, 14 Feb 2024 14:03:59 GMT

Hi @jnj!

You can refer to the uuu documentation.

https://github.com/nxp-imx/mfgtools/releases/tag/uuu_1.5.125

Re: Debug methods - IMX8QXP

jnj — Thu, 15 Feb 2024 12:51:57 GMT

Hi @Chavira ,

I will refer to this .Is there any other methods to update M4 bin?

Re: Debug methods - IMX8QXP

jnj — Thu, 15 Feb 2024 13:04:09 GMT

Hi @Chavira ,

I have used the above mentioned uuu command over USB to flash the hello_world.bin to emmc .I could flash the hello_world.bin to emmc vfat partition using the below command.

./uuu -b fat_write hello_world.bin mmc 0:1 hello_wrold.bin

After flashing I can see the hello_world.bin inside the mount point of mmcblk0p1 ie : /run/media/boot-mmcblk0p1

But while loading I am getting the below error

Re: Debug methods - IMX8QXP

Chavira — Fri, 16 Feb 2024 14:59:33 GMT

Hi @jnj !

Try to corroborate if the image was flashed correctly using the command "fatls mmc 0:1", that command shoul list all the files saved in fat partition.

After that you have to use the commands

=>fatload mmc 1:1 0x88000000 hello_world.bin
=>dcache flush
=>bootaux 0x88000000

Best Regards!
Chavira

Re: Debug methods - IMX8QXP

jnj — Fri, 16 Feb 2024 16:20:37 GMT

Hi @Chavira ,

I will check by listing the files as you mentioned. I have some more queries regarding the debugging. In which situation do we really need to debug SCU and SECU.?

Re: Debug methods - IMX8QXP

jnj — Mon, 19 Feb 2024 07:15:30 GMT

Hi @Chavira ,

I have checked the list of files in fat partition using the above mentioned command .The hello_world.bin file is showing in the list.But it throws an error when the hello_world.bin is tried to load as shown below

Re: Debug methods - IMX8QXP

Chavira — Mon, 19 Feb 2024 19:01:52 GMT

Hi @jnj!

can you try again?

I don´t get errors.

Try with this binary

Best Regards!

Chavira

Re: Debug methods - IMX8QXP

jnj — Tue, 20 Feb 2024 13:42:45 GMT

Hi @Chavira ,

Still I am facing the issue.As I discussed erlier ,already M4 core in my device is up and working .I am getting the following prints over /dev/ttyUSB2

Could it be that I am unable to update the hello_world.bin because M4 is already up and running?And also I tried to see the debug prints of scu over /dev/ttyUSB1 and /dev/ttyUSB3 by turning on the switch SW4 in the imxqxp mek.But I couldn't see any uart prints .Do I need to enable anything from the scu fw.If yes could you please help me to get the scu fw link?

Re: Debug methods - IMX8QXP

jnj — Wed, 21 Feb 2024 02:47:13 GMT

Hi @Chavira ,

Kindly help me

Re: Debug methods - IMX8QXP

Chavira — Wed, 21 Feb 2024 18:00:54 GMT

Hi @jnj!

Can you try to re-flash the board?

I am using the image 6.1.55 without errors.

You can download the image by following the link:

https://www.nxp.com/design/design-center/software/embedded-software/i-mx-software/embedded-linux-for-i-mx-applications-processors:IMXLINUX

Re: Debug methods - IMX8QXP

jnj — Wed, 21 Feb 2024 18:13:19 GMT

Hi @Chavira ,

I am working on version L5.15.71 .I will check with the 6.1.55 version also.Could you please update on this query :

"And also I tried to see the debug prints of scu over /dev/ttyUSB1 and /dev/ttyUSB3 by turning on the switch SW4 in the imxqxp mek.But I couldn't see any uart prints .Do I need to enable anything from the scu fw.If yes could you please help to guide me to update the change and kindly help me to get the scu fw link?I am little bit confused about the version"

Re: Debug methods - IMX8QXP

Chavira — Wed, 21 Feb 2024 23:33:41 GMT

Hi @jnj!

To use the UART3 to usb port we have to change the device tree for that purpose.

The board uses the UART 3 underpins "FLEXCAN2_TX" and "FLEXCAN2_RX", and the balls connected to the USB port are "SCU_GPIO0_00 " and "SCU_GPIO0_01".

To use the uart3 under those pins we have to redefine the pinctrl of the uart3 of the device tree:

https://github.com/nxp-imx/linux-imx/blob/lf-6.1.y/arch/arm64/boot/dts/freescale/imx8x-mek.dtsi

After that, we can use the uart3 under Linux.

You can check how to compile the device tree on the next link:

https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/How-to-use-Devshell-to-compile-device-tree-files/ta-p/1727428

Best Regards!

Chavira

Re: Debug methods - IMX8QXP

jnj — Thu, 22 Feb 2024 03:02:58 GMT

Hi @Chavira ,

I am little bit confused again. I want to debug SCU. In mek for the debugging scu_gpio0_IO00 and scu_gpio0_IO01 are connected to the USB converter FTD. When I checked the pinmux in the config tool these pins can be configured as SCU_UART0_TX and SCU_UART0_RX.And already a switch 4 is connected to use SCU debugging in the C0 mek.I want to utilise these pins and not UART3 for SCU under Linux

IF I am wrong, kindly correct me.