In the past weeks I had some fun poking at my unused D-Link DWR932-M router and build an upstream kernel for it, with the hope of one day running OpenWrt on it. The result can be found at
It is a 6.18-based kernel that can boot on my device and probably other ZTE zx297520v3 based chips. it is not a full OpenWrt build, and a lot more work is needed to make OpenWrt useful on these devices. But it is good enough that I'd like to show it to the community.
Here are some forum threads that have discussed these devices in the past:
My git repository contains a Readme that describes how to build and run this kernel. The tricky part is that you need to get root access on the existing firmware and access to the boot loader. I highly recommend that you get an external flash programmer to recover in case you accidentally break boot. I got my device stuck on starting U-Boot a few times and needed to access the NAND chip directly to get it working again.
I have only tested it on my D-Link DWR932-M. If you try it on other devices I'd be curious about your results. My preferred place is in the bug tracker of my gitlab respository, but I'll also keep an eye on this forum thread.