wcn6855 - stuck in 20Mhz on rx, but full 80mhz on tx

[Yaroslav Isakov]

чт, 14 дек. 2023 г. в 21:29, Yaroslav Isakov <yaroslav.isakov at gmail.com>:
>
> чт, 14 дек. 2023 г. в 16:11, Kalle Valo <kvalo at kernel.org>:
> >
> > Yaroslav Isakov <yaroslav.isakov at gmail.com> writes:
> >
> > > Thank you for answer, unfortunately, I would prefer to stay on
> > > openwrt, until it will be ruled out, that issue is not with my laptop.
> >
> > I'm not asking you to switch your firmware, I was merely asking if you
> > had tested this with a stock firmware or not. The more datapoints we
> > have the better chances there are to fix this.
>
> Unfortunately, I did not test it with stock firmware.
>
> >
> > BTW, please don't top post:
> >
> > https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches#do_not_top_post_and_edit_your_quotes
>
> Sorry, my bad - this is what Gmail does by default. Thank you for pointing out!
>
> >
> > --
> > https://patchwork.kernel.org/project/linux-wireless/list/
> >
> > https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches

Hello!

I debug this issue further, a bit - it seems that it might be a
display issue. I enabled debug for ath11k driver, and it showed me
ath11k_pci 0000:02:00.0: mac peer <peer-address> phymode 11ac-vht80

Also, when testing with iperf3, it showed me 300 mbit/s, and it was
limited by CPU on router (ksoftirqd was 99%), which is much higher
than 150 mbit showed in iw dev wlan0 link

I also tried to use 802.11n on router (HT40), and with such setting,
iw dev wlan0 link showed me 300 mbit, with 40 mhz channel width
(although iperf3 showed 200 mbit) - so, it seems that this issue is
appearing only on VHT.

My phone (Pixel 7) was able to provide me HE, with which I did not
have such issue. I cannot downgrade it to VHT, to test, if the issue
will be reproduced with phone-provided WiFi, too (after disabling
802.11ac in wpa_supplicant, it rejected to find the network)

P.S. I updated firmware for laptop wifi, from
https://github.com/kvalo/ath11k-firmware/tree/master/WCN6855/hw2.0,
but, it did not change anything.