https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/arch/arm/boot/dts?h=v6.1.111&id=c477358e66a3a6db4f1799b7415068d6660c95c3
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/arch/arm/boot/dts?h=v6.1.111&id=d22e0e1afa267ee417b2a7dff190cc6d04832418

https://lore.kernel.org/netdev/20191029123230.GM15259@lunn.ch/T/

This is not an ideal situation to have to backport the DTS after each update.
There seems to be some basic!?! support for the ethernet switch vlan thingy in the source
https://cgit.freebsd.org/src/commit/sys/arm/ti/cpsw/if_cpsw.c?id=a2c46b941e2ecfd0fffd3925dd771ee713a76ec0
I doubt there is just to change the compatible string and everything is like nothing has happened and just works.