Re: wcn7850 issues

[Kalle Valo <kvalo@kernel.org>]

+ linux-wireless

david Atkins <david@3adesign.co.uk> writes:

> ...
>> >>>         Ext Tag: EHT Operation (802.11be D3.0)
>> >>>             Ext Tag length: 8 (Tag len: 9)
>> >>>             Ext Tag Number: EHT Operation (802.11be D3.0) (106)
>> >>>             EHT Operation Parameters: 0x01, EHT Operation Information
>> Present
>> >>>                 .... ...1 = EHT Operation Information Present: True
>> >>>                 .... ..0. = Disabled Subchannel Bitmap Present: False
>> >>>                 .... .0.. = EHT Default PE Duration: False
>> >>>                 .... 0... = Group Addressed BU Indication Limit: False
>> >>>                 ..00 .... = Group Addressed BU Indication Exponent: 0
>> >>>                 00.. .... = Reserved: 0x0
>> >>>             Basic EHT-MCS And Nss Set: 0x44444444
>> >>>             Control: 0x02, Channel Width: 80 MHz EHT BSS bandwidth
>> >>>                 .... .010 = Channel Width: 80 MHz EHT BSS bandwidth (2)
>> >>>                 0000 0... = Reserved: 0x00
>> >>>
>> >>> Are you saying the ath12k driver does not support these features? If
>> >>> not can
>> >> you clarify the issue so I can raise with the AP team.
>> >>>
>> >> ath12k/WCN7850 supports EHT, but with NSS only 2. Here the AP
>> >> requires NSS to be no less than 4, that is why EHT connection was disabled.
>> >
>> > Which field is requiring NSS of 4, I'm only seeing a maximum of 4, the
>> Qualcomm windows driver will connect to the same AP, we had assumed that
>> that ath12k would do the same.
>> Basic EHT-MCS And Nss Set: 0x44444444
>
> My understanding of the spec is that there are maximum numbers of
> streams though, are you saying the AP has to advertise 0x22222222
> which would then prevent a 4x4 client (say an extender) from
> connecting with 4 streams? I note that the Qualcomm windows driver for
> Hamilton works with the AP and an Intel BE200 also works both of which
> will be in at most 2x2

Did you test Intel BE200 with the Windows driver? Johannes mentioned
that ieee80211_verify_sta_eht_mcs_support() in mac80211 checks this so I
would assume that iwlwifi also behaves like ath12k.

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