[K4sum1]

So after having WiFi issues with two Marvell SoC based routers on modern builds, WRT1900ACv2 and WRT3200ACM, I had decided to finally get around to trying DD-WRT on my RT-AC88U.

After installing r62240 and checking out the WiFi settings, I've found my RT-AC88U to be missing a bunch of 5GHz channels as compared to my WRT1900ACv2. At 20MHz on my WRT1900ACv2, I can select 36, 40, 44, 48, 52, 56, 60, 64, 100, 104, 108, 112, 116, 120, 124, 128, 132, 136, 140, 144, 149, 153, 157, and 161. However on the RT-AC88U, I can only select 36, 40, 44, 48, 149, 153, 157, 161, and 165. I am missing everything from 52 and 144, and this sucks in a congested area. Especially since in my findings, that limited channel selection is the most likely to be congested. This gets even worse at 80MHz where the WRT1900ACv2 is only missing 64, 153, and 161, but all I can pick on the RT-AC88U is channels 36 and 149.

I had noticed an experimental WiFi driver build and tested it in case it could fix the issue, but it completely broke WiFi on the router for me. First boot after updating to the build, WiFi lights are on, but the Wireless tab is gone and there's no WiFi signal coming from router. Second boot, WiFi lights are off, otherwise the same. Factory resetting the router doesn't change anything either. Going back to the regular build fixes WiFi and the Wireless tab appears again.

[Per Yngve Berg]

What Regulatory Domain?

[kernel-panic69]

Regulatory domain and extension channel selection dependent, I reckon:

[SOLVED @ r49392] Netgear R7000P 5 GHz VAP - page 2

[K4sum1]

My Regulatory Domain is set to the United States, and I am in the United States.

I took a look at that thread, and nvram set brcm_unlock=1 unlocked channels 52, 100, 116, 132, and 149 for selection at 80MHz. At 20MHz, it has all the channels of the WRT routers now, plus 165. The other missing channels at 80MHz look to be that the RT-AC88U requires changing the Extension Channel before the other channels show, while the WRT routers automatically change the Extension Channel with the band selected. I'll just keep lower lower for now unless I find a crowded config that would benefit from something else. nvram set 1:disband5grp=0 didn't seem to do anything for me here.

Wonder why this is not the default.

[kernel-panic69]

Because Regulatory Domain + Extension Channel selected determines available channels per the driver on Broadcom (as well as all the others), generally speaking.