Device Tree - Overlay depending on cmdline argument

Robotics & Edge Computing Jetson & Embedded Systems Jetson AGX Xavier
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Hi NVidia Team

Is there a possibility to change a device-tree setting of a device with an overlay, depending on a cmdline argument added to /boot/extlinux/extlinux.conf? If yes, can you describe how we can achieve it?
The background is that on our board, we use as a PHY the chip KSZ9031. To make it work with the Jetson AGX Xavier Module, we had to add to the device tree the fixed-link node with a defined speed of 1000. Now it we use the device with an 100 Mbit Switch, it will not connect (ethtool reports onliy 1000Mbit supported). Therefore we would like to have the possibility to change the speed over a kernel argument.
If you even have a better solution, let us know.
Thank you for your help.

Best regards

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hello sevm89,

how about loading device tree blob from file system?
it’s CBoot functionality includes a default booting scan sequence, you should modify extlinux.conf by adding FDT entry.
please refer to CBoot session for more details. thanks

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hello JerryChang

Thank you for your fast help, that worked.

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