[FS#535] 5GHz radios not working properly on Netgear R8000

[LEDE Bugs]

A new Flyspray task has been opened.  Details are below. 

User who did this - rfr (rfr) 

Attached to Project - LEDE Project
Summary - 5GHz radios not working properly on Netgear R8000
Task Type - Bug Report
Category - Kernel
Status - Unconfirmed
Assigned To - 
Operating System - All
Severity - High
Priority - Very Low
Reported Version - lede-17.01
Due in Version - Undecided
Due Date - Undecided
Details - After upgrading my R8000 from Chaos Calmer (15.05.1) to LEDE Reboot (17.01.0-rc2, r3131-42f3c1f), I found that I could no longer get the 5GHz radios to work as before. The 2.4GHz radio is fine.

In CC I was using the following configuration:
- radio0 on channel 149, country code '00', VHT80
- radio2 on channel 48, country code '00', VHT80

The firmware apparently only accepts 00 and US as country codes, which is why I was using 00. This discussed at length in: https://forum.openwrt.org/viewtopic.php?id=55367&p=19 (and previous pages)

In 17.01.0-rc2, I can't get radio0 to come up at all. radio2 can be configured, still on channel 48 and country 00, but in VHT40 mode. If I use VHT80, it stays disabled.

This was discussed previously in this forum post: https://forum.lede-project.org/t/r8000-5ghz-wifi-issue/236 and I get the same error messages and channel selection as the OP, so I will not repeat them here.

I'm not sure if this issue is really related to the country code setting, but I will note that the factory system apparently sets the country code to "EU":

root at x6:~# nvram show | grep country_code
wl1_country_code=EU
wl0_country_code=EU
wl2_country_code=EU
wl_country_code=
root at x6:~#

I see that LEDE carries a patch on brcmfmac which translates the configured country code to an internal code for the firmware on this specific model (https://git.lede-project.org/?p=source.git;a=blob_plain;f=package/kernel/mac80211/patches/863-brcmfmac-add-in-driver-tables-with-country-codes.patch;hb=refs/heads/lede-17.01). I'm willing to test patches if anyone knows the right internal country code for Europe.

More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=535