So I was excited to upgrade my build to Warrior, and it’s gone mostly well, but I’m having one problem that’s worrying me a bit. I have a serial port attached to the Uart for debugging and after the mender update from Thud to Warrior it stops working. It’ll show the U-boot startup, but the last thin…

A comparison of fw_printenv from a working device and a non-working one would be useful. Could be that some arguments have changed that affect both boot loader and kernel, and when upgrading with Mender, only the kernel is touched.

@mirzak Ok, yeah, that’ll explain it. Will need to decide what the best course of action will be.

Also, I did confirm that the mender update itself didn’t cause any problems. For myself I’m going to set the Linux version back to the version that the Raspberry Pi used in Thud and see if I get the old dtb and the serial port survives the update

Ok, looks like setting my Linux version back to 4.14 solved the uart issue and will likely have fixed any other dtb-related issues I might have run into later.

Uart stopped working after update from Thud to Warrior

General Discussions

mirzak October 30, 2019, 8:43am 3

Also checkout the known issues section in this thread, Raspberry Pi 3 Model B/B+.

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Uart stopped working after update from Thud to Warrior

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