After upgrading to newest firmware, in Wireless Overview, radio0 and radio1 say Generic unknown and Wi-Fis associated with them stopped working. radio2 and radio3 display MediaTek MT7981 802.11ax/b/g/n and MediaTek MT7981 802.11ac/ax/n so they seem to be OK (although I never used them).
I found similar problem that was supposedly fixed by installing a specific kmod-*-firmware package, but I don't want to destroy my router by messing around with wrong pkgs.
Indeed it is assumed that the right firmware is installed to drive the hardware. There is no harm in installing a kmod-*-firmware file. In worst case scenario it won't be used. By default the image should contain all necessary drivers.
There should be no radio2 and 3. Did some bad merging of data occured ?
Maybe. I chose to keep the config during the upgrade. However, even when I deleted WiFi configuration, I am still left with 4 radios. How do I remove them?
You could remove all the wifi-device blocks from /etc/config/wireless then reboot and it will generate a new radio0 and radio1 (not necessarily in the same order as the last version though). But it is much better to reset all configuration between major releases as there are likely to be other incompatibilities.
