Using standard UARTs with mainline kernel


We want to utilize the standard TK1 UARTs. However whenever the baud rate is set the following error occurs:

stty -F /dev/ttyTHS3 115200
stty: /dev/ttyTHS3: Input/output error

and dmesg states:

[ 2354.908929] serial-tegra 70006300.serial: configured baud rate is out of range by -6
[ 2354.916723] serial-tegra 70006300.serial: Failed to set baud rate
[ 2354.925069] serial-tegra 70006300.serial: Uart HW init failed, err = -5

This example worked well with the downstream kernel and BSP2.8. Do we need to manipulate the device tree? How can we use the UARTs with out setup?

Apalis TK1 V1.2A
Ixora V1.2A
BSP3.0 with mainline kernel 5.4


Hi @qojote ,

Unfortunately, the combination of BSP3.0 with mainline kernel 5.4 is not something Toradex supports out of the box.
If you have a look at our Embedded Linux Release Matrix you can see what Toradex supports.

I reproduced the same command with the BSP3.0 based on mainline kernel 4.14. And on my side, this command works without triggering an error.

Best Regards

The same error occurs when using the standard Toradex image for BSP5.4.0 TK1 mainline. So i guess its really related to the kernel version. A quick look into the patches for 4.14 recipe shows that there was a patch to add “nvidia,tegra30-hsuart” to the compatible string… but this is already part of the 5.4 device tree. Can you maybe point me into the right direction what needs to be done to get the UARTs working?

Hi @qojote ,

I was able to reproduce the issue on BSP5.4 TK1 mainline.

We are currently looking into the issue. I will reach out to you again as soon as I have new about it.

Best Regards

1 Like