CM3I WiFi device tree

#1

Hi! I have a CM3I (v1.31) on an E25 base board (D4E16 v1.41, in case it helps), which comes with the optional AP6256 WiFi+BT module. Unfortunately, it isn’t included in the mainline or Armbian kernel device trees for the CM3I and isn’t detected when the device boots.

I thought I’d have a go at modifying the device tree based on the CM3, which looks like it uses the same module and connects it to the SoC in a similar way - as far as I can tell from the schematics / block diagrams. Sadly, I don’t know much about writing device tree code, and I haven’t been able to get it to work. (I’m happy to post one of the mods I’ve tried, if that would be useful?)

Does anyone know if anyone has posted a patch for the WiFi on the CM3I anywhere? Or, please could someone help me figure out what the correct patch would be?

Thanks!

#2

I noticed that someone uploaded an armbian-dt-overlays repo to Github last week. Thanks!

I tried that, and it seemed to work with one additional tweak: It was complaining about missing firmware, so I ran the following:

cd /usr/lib/firmware/brcm/
ln -s brcmfmac43456-sdio.bin brcmfmac43456-sdio.radxa,e25.bin
ln -s brcmfmac43456-sdio.txt brcmfmac43456-sdio.radxa,e25.txt

And rebooted. It ran for about 10 minutes and was working well, but then it seems to have crashed and I’m getting messages like these in the dmesg output every 6s:

[Mon Oct 16 10:49:50 2023] brcmfmac: brcmf_sdio_bus_rxctl: resumed on timeout
[Mon Oct 16 10:49:50 2023] ieee80211 phy1: brcmf_cfg80211_dump_station: BRCMF_C_GET_ASSOCLIST failed, err=-110

Does anyone have an idea what might be causing that? Thanks!