I'm trying to add this device to make it work with OpenWrt.
Model LT18 AX1800 Wi-Fi 6 4G Cat18 Router
Hardware CPU: Mediatek Dual Core 880MHz
4G Module: Quectel EG18 (Qualcomm)
The version of the mediatek chip is unclear but it must be the same than for Cudy LT400.
I have this device too.
Wed Jul 27 10:41:21 2022 kern.notice kernel: [ 0.000000] Linux version 4.4.140 (jenkins@cudy_release) (gcc version 5.4.0 (LEDE GCC 5.4.0 1.9.1) ) #0 SMP Tue May 24 08:55:15 2022
Wed Jul 27 10:41:21 2022 kern.info kernel: [ 0.000000] SoC Type: MediaTek MT7621 ver:1 eco:3
The diagnostics log in their firmware reports MT7621.
Also, for what its worth, the log reports it is a quad core, or at least brings up 4 cpus.
For what its worth, I believe it already runs a version of OpenWRT, since their WebUI is at /luci/. Perhaps we could ask Cudy to give us the base configs?
Update: I asked them.
880 MHz and 4 threads (not cores!) suggests MT7621A. Plenty of devices with that SoC that are supported by OpenWrt.
Look this over:
Cudy OpenWRT Downloads
Likely the X6 is similiar but would lack the LTE/Sim card function. Focus on the OEM bootlogs to see if you can ID the LTE chipset and then search the OpenWRT database to see if any other devices use that chipset.
Cudy is not very open to give anything… . I would be great if for the X6 the LTE funtion is working 100%. It is the most important to me that the Quectel modem works, I could be ok without wifi.
If someone give a try and running without the proper Quectel drivers, just with the Openwrt, please let me know.
They should all work with that chipset, that it is clear but let's see if with X6 we have complete funtionality 
, come on Devs!
It might have 2 cores, it is a bit slow compared to others in thos price range, but I guess they spend a lot in the modem and the left all the flagship routers of the brand under 1Ghz. Which depending or the funtionality you may miss it.
Nice, hopefully if myself and a few others ask nicely (I already asked via the support email) they could add the LT18 to that page.
The module is "qmi_wwan_q", I found a script for the Raspberry Pi here: https://github.com/sixfab/Sixfab_QMI_Installer/blob/main/qmi_install.sh
Might be able to manually download the files referenced and integrate into OpenWRT.
Or perhaps its already supported:
The modem seems to be connected via an internal-only USB3 bus.
qmi_wwan_q 2-1:1.4 wwan0: register 'qmi_wwan_q' at usb-1e1c0000.xhci-1, WWAN/QMI device
Even if the quetel chip is in a pci-e slot or soldered on, dmesg reports it on the usb bus. You should be good. Next step is to see how qmi_wwan_q is implemented in other builds.
Update: They responded to my GPL request with this page (which offers a tar.gz):
I haven't poked around it enough to see if it is helpful for this particular model.
Cudy's is shaping up to be a responsible company and now is at the top of my recommended list.
Please note the GPL code only includes the wired part, for wireless, please check the other open source.
If you are of the opinion that Cudy Technology should offer further source code subject to the GPL, please contact us via support@cudy.com.
It is not really "opinion" but settled case law. Under the GPL 2.0 license, a company like Cudy is free to use OpenSource software in their products. The only stipulation is that they publish any modifications they make to the software.
This has been upheld in prior court cases:
I think they were just quoting the website. But I also think OpenWRT already has packages for the wireless devices. I still haven't had time to set up and test a build environment plus right now the LT18 is my main router.
The biggest drawback that may make this device not worth it is the fact it only has 16MB Flash and no user-accessible storage for an extroot.
kern.warn kernel: [ 2.503489] MediaTek Nand driver init, version v2.1 Fix AHB virt2phys error
kern.info kernel: [ 2.510793] spi-mt7621 1e000b00.spi: sys_freq: 50000000
kern.info kernel: [ 2.516961] m25p80 spi32766.0: using chunked io (size=32)
kern.info kernel: [ 2.522345] m25p80 spi32766.0: XM25QH128C (16384 Kbytes)
kern.notice kernel: [ 2.527791] 7 ofpart partitions found on MTD device spi32766.0
kern.notice kernel: [ 2.533594] Creating 7 MTD partitions on "spi32766.0":
kern.notice kernel: [ 2.538730] 0x000000000000-0x000000030000 : "u-boot"
kern.notice kernel: [ 2.544819] 0x000000030000-0x000000040000 : "u-boot-env"
kern.notice kernel: [ 2.551214] 0x000000040000-0x000000050000 : "factory"
kern.notice kernel: [ 2.557320] 0x000000fd0000-0x000000fe0000 : "debug"
kern.notice kernel: [ 2.563134] 0x000000fe0000-0x000000ff0000 : "backup"
kern.notice kernel: [ 2.569141] 0x000000ff0000-0x000001000000 : "bdinfo"
kern.notice kernel: [ 2.575019] 0x000000050000-0x000000fd0000 : "firmware"
kern.notice kernel: [ 2.612553] 2 uimage-fw partitions found on MTD device firmware
kern.notice kernel: [ 2.618494] 0x000000050000-0x0000003a591a : "kernel"
kern.notice kernel: [ 2.624624] 0x0000003a591a-0x000000fd0000 : "rootfs"
kern.notice kernel: [ 2.630767] mtd: device 8 (rootfs) set to be root filesystem
kern.notice kernel: [ 2.636532] 1 squashfs-split partitions found on MTD device rootfs
kern.notice kernel: [ 2.642692] 0x000000ac0000-0x000000fd0000 : "rootfs_data"