Subject: Re: VHT 160Mhz and nss related config.
To: Adrian Chadd <adrian.chadd@gmail.com>
References: <0082a9e3-83f3-9bc3-af43-b890b91cfd93@candelatech.com>
 <CAJ-Vmo=-JBrkmUPcYrRbARYuWv_=-MeQpPwAN_0J3v8pA5mPnw@mail.gmail.com>
Cc: ath10k@lists.infradead.org, linux-wireless@vger.kernel.org
From: Ben Greear <greearb@candelatech.com>
Message-ID: <c2e26f4e-f6a9-c662-b1a1-d0e0eb144af8@candelatech.com> (sfid-20170211_002618_824601_C158CA58)
Date: Fri, 10 Feb 2017 15:26:13 -0800
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On 02/10/2017 03:23 PM, Adrian Chadd wrote:
> Is it limited on both tx and rx or only one?

Both, as I understand it.  I think maybe we could use the max-tx-rate and max-rx-rate
fields in the vht mcs info field to give user-space a clue.

Thanks,
Ben

>
>
>
> Adrian
>
> On Feb 10, 2017 2:58 PM, "Ben Greear" <greearb@candelatech.com <mailto:greearb@candelatech.com>> wrote:
>
>     So, it appears that the ath10k QCA9984 4x4 160Mhz chip can do 4x4 MIMO at VHT80, but
>     it can do only 2x2 MIMO at VHT160/80+80.
>
>     When configuring a peer, we need to tell the firmware the number of spatial streams
>     of the peer at VHT160 and at VHT80 and lower.  They are not the same value.
>
>     I cannot think of any standard way to get this information based on VHT capabilities
>     and such.  Currently, one could just assume VHT160 NSS is 1/2 of the VHT80 NSS,
>     but that is unlikely to be true for all vendors.
>
>     Any ideas?
>
>     Thanks,
>     Ben
>
>     --
>     Ben Greear <greearb@candelatech.com <mailto:greearb@candelatech.com>>
>     Candela Technologies Inc  http://www.candelatech.com
>


-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com