Lost UART1 and UART2 on Rasp4

Product support balenaOS
1

Hi,

I had a fleet of devices which were running balenaOS 6.0.50+rev1 and using UART ports on a Rasp4. On that fleet if I issued the command ls /dev/ttyA* I got /dev/ttyAMA0 /dev/ttyAMA1 /dev/ttyAMA2.

However, new devices have been added using balenaOS 6.5.21+rev2 as my base image and all my UARTs are now failing and not appearing causing errors in the main code.

This is from BalenaOS 6.0.50+rev1

root@d3b62b8:~# cat /mnt/boot/config.txt
avoid_warnings=1
disable_splash=1
dtparam=i2c_arm=on
dtparam=spi=on
dtparam=audio=on
enable_uart=0
gpu_mem=16
dtoverlay=vc4-kms-v3d
dtoverlay=uart2
dtoverlay=uart3

This is from BalenaOS 6.5.21+rev2

root@2b63eb9:~# cat /mnt/boot/config.txt     
dtparam=i2c_arm=off
dtparam=spi=on
dtparam=audio=on
enable_uart=0
gpu_mem=16
avoid_warnings=1
disable_splash=0
dtoverlay=vc4-kms-v3d
dtparam=uart2
dtparam=uart3

For some reason, with exactly the same Define DT overlays in both OS versions, in the latest OS I am seeing dtparam=uart2 instead of dtoverlay=uart2 for example.

Has anyone experienced similar issues and has the kernel / overlays changed please?

2

The kernel changed from version 5.15.92 in balenaOS 6.0.50+rev1 to kernel 6.12.20 in balenaOS 6.5.21+rev2. What exactly did you enter for the “Define DT overlays”?

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