Re: [PATCH 0/6] wifi: rtw89: preparation of TDMA-based MCC (STA+P2P)

[Kalle Valo <kvalo@kernel.org>]

Ping-Ke Shih <pkshih@realtek.com> writes:

> On Wed, 2023-08-23 at 16:56 +0300, Kalle Valo wrote:
>> 
>> Ping-Ke Shih <pkshih@realtek.com> writes:
>> 
>> > TDMA-based MCC (STA+P2P) is a kind of multiple interfaces concurrence.
>> > Basically, driver is to calculate timeslot pattern and firmware follows
>> > the pattern to switch channels. Since BT-coexistence is also a TDMA-based
>> > mechanism, also consider BT timeslot into pattern if BT devices present.
>> 
>> What do you mean with TDMA here? It something like that in STA mode the
>> driver enables 802.11 PS mode before going to another channel? Or
>> something else?
>> 
>
> Yes, when it is working as STA mode or GC, using 802.11 PS mode before
> switching channel. When it plays as GO, NoA is used to inform GC absent
> timing. 
>
> For example, STA on channel 1 + GO on channel 11, and preserve some
> time slot for BT
>
>
>                              (1)
>  channel 1   (STA)   +++++++++
>
>                               (2)
>  channel 11  (GO)             +++++++++
>
>  BT                                    ++++++++
>
>                      |<----------------------->|
>                        Period (or cycle time)
>  
> (1) issue null with power bit
> (2) issue beacon with NoA 
>
>
> Though STA and GO are in different channels, they don't operate at
> the same time. This is the reason I point "TDMA" to prevent
> misunderstanding two virtual interfaces can operate two channels
> at the same time, which may be called DBS or DBCC. But, I'm trying
> to explain hardware capability correctly.

Got it, thanks for the great explanation.

Just out of curiosity, how do you create your ascii diagrams? Is there
some nifty tool to help with those? :)

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