From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail2.candelatech.com ([208.74.158.173]:44118 "EHLO mail2.candelatech.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751217AbdBLQFs (ORCPT ); Sun, 12 Feb 2017 11:05:48 -0500 Subject: Re: VHT 160Mhz and nss related config. To: Sebastian Gottschall , Adrian Chadd References: <0082a9e3-83f3-9bc3-af43-b890b91cfd93@candelatech.com> <589F50B8.4020609@candelatech.com> <02b7f70a-7da2-f2e4-8904-bdffc3ca90a1@candelatech.com> <159ba156-cf2d-db0d-a6af-2557b9bfa6b6@dd-wrt.com> Cc: "linux-wireless@vger.kernel.org" , ath10k From: Ben Greear Message-ID: (sfid-20170212_170747_052607_170970DF) Date: Sun, 12 Feb 2017 08:05:45 -0800 MIME-Version: 1.0 In-Reply-To: <159ba156-cf2d-db0d-a6af-2557b9bfa6b6@dd-wrt.com> Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 02/12/2017 02:56 AM, Sebastian Gottschall wrote: > Am 11.02.2017 um 20:38 schrieb Ben Greear: >> On 02/11/2017 10:21 AM, Sebastian Gottschall wrote: >>> Am 11.02.2017 um 18:58 schrieb Ben Greear: >>>> On 02/10/2017 08:37 PM, Adrian Chadd wrote: >>>>> On 10 February 2017 at 20:22, Sebastian Gottschall >>>>> wrote: >>>>>> i really can't believe this. if this is true the 160 mhz mode would not >>>>>> make any sense. >>>>>> the maximum tx / rx rate for 4x4 vht80 and 2x2 vht160 is identical. so >>>>>> vht160 would not increase performance in any way >>>>> >>>>> Well, if it can also do 2x2 MU-MIMO at 160MHz then it can be a >>>>> perfectly fine STA to a 4x4 160MHz MU-MIMO chip that can actually >>>>> transmit 2x2 rates to different MU-MIMO peers. >>>>> >>>>> That's the outstanding question I have - is it like, 2x2 MU only, or >>>>> is it say, 2 concurrently different spatial stream 2x2 MU? Ie, can you >>>>> have 2 peers, different VHT spatial groups (or 4 peers, 1 spatial >>>>> group each) all going at the same time? >>>>> >>>>> I'm .. not even sure how you're supposed to cleanly negotiate that you >>>>> can do 4NSS in VHT80 but 2NSS in VHT160 to a peer... that only makes >>>>> sense if you're doing lots of 1NSS and 2NSS MU-MIMO peers.. >>>> >>>> I think using the max-rx-rate logic might could imply this, but I am not sure >>>> many drivers fill this out properly. >>>> >>>> Looks like a mess waiting to happen to me. >>>> >>>> Even if you can do 1x1 160Mhz MU-MIMO to two stations, and I am not certain you >>>> can since in 80Mhz you can only do a 1x1 and a 2x2 (not two 2x2). >>>> >>>> So, from what I know currently, 80+80 is not that useful on the 9984 NIC... >>> never tried 80+80 since i need to enhance the channel logic alot in my firmware code to handle it. would be great enough if vht160 would work as expected and >>> i'm not sure right now if it really works, even if the interface initialized correctly it assocs only with vht80 >> >> 160Mhz is really implemented as 80+80 internally it seems, so what I meant is that >> 160Mhz or 80+80 both have the 2x2 restriction. > since i have a older fw source. can you give me a hint where you found a indication that its just 2x2? Look for: MAX_SPATIAL_STREAMS_SUPPORTED_AT_160MHZ Thanks, Ben -- Ben Greear Candela Technologies Inc http://www.candelatech.com From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail2.candelatech.com ([208.74.158.173]) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1ccwfC-0004f6-3M for ath10k@lists.infradead.org; Sun, 12 Feb 2017 16:06:12 +0000 Subject: Re: VHT 160Mhz and nss related config. References: <0082a9e3-83f3-9bc3-af43-b890b91cfd93@candelatech.com> <589F50B8.4020609@candelatech.com> <02b7f70a-7da2-f2e4-8904-bdffc3ca90a1@candelatech.com> <159ba156-cf2d-db0d-a6af-2557b9bfa6b6@dd-wrt.com> From: Ben Greear Message-ID: Date: Sun, 12 Feb 2017 08:05:45 -0800 MIME-Version: 1.0 In-Reply-To: <159ba156-cf2d-db0d-a6af-2557b9bfa6b6@dd-wrt.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "ath10k" Errors-To: ath10k-bounces+kvalo=adurom.com@lists.infradead.org To: Sebastian Gottschall , Adrian Chadd Cc: "linux-wireless@vger.kernel.org" , ath10k On 02/12/2017 02:56 AM, Sebastian Gottschall wrote: > Am 11.02.2017 um 20:38 schrieb Ben Greear: >> On 02/11/2017 10:21 AM, Sebastian Gottschall wrote: >>> Am 11.02.2017 um 18:58 schrieb Ben Greear: >>>> On 02/10/2017 08:37 PM, Adrian Chadd wrote: >>>>> On 10 February 2017 at 20:22, Sebastian Gottschall >>>>> wrote: >>>>>> i really can't believe this. if this is true the 160 mhz mode would not >>>>>> make any sense. >>>>>> the maximum tx / rx rate for 4x4 vht80 and 2x2 vht160 is identical. so >>>>>> vht160 would not increase performance in any way >>>>> >>>>> Well, if it can also do 2x2 MU-MIMO at 160MHz then it can be a >>>>> perfectly fine STA to a 4x4 160MHz MU-MIMO chip that can actually >>>>> transmit 2x2 rates to different MU-MIMO peers. >>>>> >>>>> That's the outstanding question I have - is it like, 2x2 MU only, or >>>>> is it say, 2 concurrently different spatial stream 2x2 MU? Ie, can you >>>>> have 2 peers, different VHT spatial groups (or 4 peers, 1 spatial >>>>> group each) all going at the same time? >>>>> >>>>> I'm .. not even sure how you're supposed to cleanly negotiate that you >>>>> can do 4NSS in VHT80 but 2NSS in VHT160 to a peer... that only makes >>>>> sense if you're doing lots of 1NSS and 2NSS MU-MIMO peers.. >>>> >>>> I think using the max-rx-rate logic might could imply this, but I am not sure >>>> many drivers fill this out properly. >>>> >>>> Looks like a mess waiting to happen to me. >>>> >>>> Even if you can do 1x1 160Mhz MU-MIMO to two stations, and I am not certain you >>>> can since in 80Mhz you can only do a 1x1 and a 2x2 (not two 2x2). >>>> >>>> So, from what I know currently, 80+80 is not that useful on the 9984 NIC... >>> never tried 80+80 since i need to enhance the channel logic alot in my firmware code to handle it. would be great enough if vht160 would work as expected and >>> i'm not sure right now if it really works, even if the interface initialized correctly it assocs only with vht80 >> >> 160Mhz is really implemented as 80+80 internally it seems, so what I meant is that >> 160Mhz or 80+80 both have the 2x2 restriction. > since i have a older fw source. can you give me a hint where you found a indication that its just 2x2? Look for: MAX_SPATIAL_STREAMS_SUPPORTED_AT_160MHZ Thanks, Ben -- Ben Greear Candela Technologies Inc http://www.candelatech.com _______________________________________________ ath10k mailing list ath10k@lists.infradead.org http://lists.infradead.org/mailman/listinfo/ath10k