ath11k: QCN9074: low HE-MCS index

[Tanguy Serrat]

> FWIW for anyone seeing this that might wonder: yes, this is the same
> issue that is already brought up on the lists here:

> https://lore.kernel.org/all/1326a6e4-758d-3344-d90c-8a126748b034@gmail.com/

Thank you Thorsten. This is a separate new issue. I have opened a new
ticket here with my latest findings:
https://bugzilla.kernel.org/show_bug.cgi?id=217652

Any help would be greatly appreciated, this is quite blocking in our
product development.


Le lun. 26 juin 2023 à 15:50, Linux regression tracking (Thorsten
Leemhuis) <regressions at leemhuis.info> a écrit :
>
> On 26.06.23 14:27, Tanguy Serrat wrote:
> >
> > In my quest to get 2x QCN9074 paired and achieving high throughput
> > data transfers, I am now facing issues with the AP configuration.
> >
> > Specifically, I cannot get more than HE-MCS 5 (AP and client 50cm
> > apart) although SNR and RSSI are always very strong and supposedly in
> > specs (SNR > 40db or RSSI < -48db).
>
> FWIW for anyone seeing this that might wonder: yes, this is the same
> issue that is already brought up on the lists here:
>
> https://lore.kernel.org/all/1326a6e4-758d-3344-d90c-8a126748b034@gmail.com/
>
> Sadly nothing much came from it (and coincidentally I tried to revive
> that thread a few minutes after Tanguy Serrat sent the quoted mail,
> which was an hour before I saw it -- aka: race condition). Well, maybe
> one of these mails hopefully will help.
>
> Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
> --
> Everything you wanna know about Linux kernel regression tracking:
> https://linux-regtracking.leemhuis.info/about/#tldr
> If I did something stupid, please tell me, as explained on that page.
>
> #regzbot ^backmonitor: d90c-8a126748b034 at gmail.com/
>
> > iw wlp6s0 link
> > Connected to 00:15:61:27:cd:dc (on wlp6s0)
> > SSID: Space
> > freq: 5745
> > RX: 1073584482 bytes (708567 packets)
> > TX: 355824214 bytes (256143 packets)
> > signal: -40 dBm
> > rx bitrate: 1729.3 MBit/s 160MHz HE-MCS 4 HE-NSS 4 HE-GI 0 HE-DCM 0
> > tx bitrate: 1729.3 MBit/s 160MHz HE-MCS 4 HE-NSS 4 HE-GI 0 HE-DCM 0
> >
> > In this case iperf3 shows ~950Mbits/s transfer speed. I am hoping to
> > get at least twice as much.
> >
> > It seems to me that either mac80211, ath11k or hostapd are not
> > advertising the available capabilities correctly. I have tried setting
> > hostapd he_basic_mcs_set=65530 or others but did not help.
> >
> > I have added ieee80211_regdom=FR option to cfg80211 module on the AP
> > side. Channel selection is done with ACS survey. I also tried other
> > channels/frequencies without success eg. 5500Mhz.
> >
> > iw reg get
> > global
> > country FR: DFS-ETSI
> > (2400 - 2483 @ 40), (N/A, 20), (N/A)
> > (5150 - 5250 @ 80), (N/A, 23), (N/A), NO-OUTDOOR, AUTO-BW
> > (5250 - 5350 @ 80), (N/A, 20), (0 ms), NO-OUTDOOR, DFS, AUTO-BW
> > (5470 - 5725 @ 160), (N/A, 26), (0 ms), DFS
> > (5725 - 5875 @ 80), (N/A, 13), (N/A)
> > (5945 - 6425 @ 160), (N/A, 23), (N/A), NO-OUTDOOR
> > (57000 - 71000 @ 2160), (N/A, 40), (N/A)
> >
> > phy#0 (self-managed)
> > country US: DFS-FCC
> > (2402 - 2472 @ 40), (6, 30), (N/A)
> > (5170 - 5250 @ 80), (N/A, 30), (N/A), AUTO-BW
> > (5250 - 5330 @ 80), (N/A, 24), (0 ms), DFS, AUTO-BW
> > (5490 - 5730 @ 160), (N/A, 24), (0 ms), DFS, AUTO-BW
> > (5735 - 5895 @ 160), (N/A, 30), (N/A), AUTO-BW
> > (5945 - 7125 @ 160), (N/A, 27), (N/A), NO-OUTDOOR, AUTO-BW
> >
> > Current setup is:
> > - Intel x86
> > - Ubuntu 22.04
> > - Kernel built from ath 6.4.0-rc6-wt-ath+ (commit:
> > c60d15f389ef9832a8da410e438d81b10327751f)
> > with commit reverted from the bug ticket I opened
> > (https://bugzilla.kernel.org/show_bug.cgi?id=217536).
> > - 1x QCN9074 as AP, 1x as managed client 50cm apart
> > - Both AP and Client are running with the latest 2.7.0 FW.
> >
> > I have started from this ticket
> > (https://bugzilla.kernel.org/show_bug.cgi?id=217286) hostapd config
> > file, and adapted, please find attached.
> >
> > Anyone seeing what could be my issue / how I could debug further ?
> >
> > Thank you !
> > Tanguy
> >
> >