[ath9k-devel] ath9k:Descriptor(or Per packet) based TPC

[Anu Krishnamoorthy <anuramku@yahoo.com>]

Thanks for the reply. I don't know about the hardware register bit. That's the answer I am trying to find out from the forum if you or anyone knows how to enable this feature. I would really appreciate if you could recollect and let me know the hardware register bit you think would do the trick.

Thanks,
Ramkumar. 

--- On Tue, 11/24/09, Siva Rama Krishna Rao J. Y. <welcomesiva@yahoo.com> wrote:

> From: Siva Rama Krishna Rao J. Y. <welcomesiva@yahoo.com>
> Subject: Re: [ath9k-devel] ath9k:Descriptor(or Per packet) based TPC
> To: "Luis R. Rodriguez" <lrodriguez@atheros.com>, "Anu Krishnamoorthy" <anuramku@yahoo.com>
> Cc: "ath9k-devel at lists.ath9k.org" <ath9k-devel@lists.ath9k.org>
> Date: Tuesday, November 24, 2009, 9:33 PM
> There
> would be additional hardware register bit setting to enable
> per packet based TPC. Have you enabled it? I dont remember
> the exact bit offline.
> 
> Regards
> Siva
> 
> 
> --- On Tue, 11/24/09, Anu Krishnamoorthy
> <anuramku@yahoo.com> wrote:
> 
> From: Anu Krishnamoorthy <anuramku@yahoo.com>
> Subject: Re: [ath9k-devel] ath9k:Descriptor(or Per packet)
> based TPC
> To: "Luis R. Rodriguez"
> <lrodriguez@atheros.com>
> Cc: "ath9k-devel at lists.ath9k.org"
> <ath9k-devel@lists.ath9k.org>
> Date: Tuesday, November 24, 2009, 11:34 PM
> 
> Hi Luis,
> ?
> Thanks for the reply. I believe the "sc" struct
> and the curtxpow, config.txpowlimit are used to
> store/configure the global power(iwconfig
>  <interface> txpower <val>) for all the packets
> that are transmitted using a wireless interface.
> ?
> If you want a differential treatment(use specific power for
> only certain packets) then per packet/descriptor based TPC
> has to be used. The descriptor portion is part of the
> "transmit buffer" (File:ath9k/xmit.c, Function:
> ath_tx_start_dma, Argument: bf, attribute bf_desc). There
> are functions to set various fields of this descriptor
> struct such as
> ath9k_hw_set11n_txdesc, ath9k_hw_set11n_ratescenario (File:
> ath9k/mac.c) that currently do not make use of these fields.
> 
> 
> When I tried to populate the tx power control fields(for a
> 5416 chip based card)
> within the descriptor for every packet buffer, I did not
> find any effect from the power setting(used the received
> signal strength for measurement) when I used a sniffer. 
> Hence I am wondering is more need to be done to force the
> other functional blocks with the HW to read and
>  apply these descriptors? How to force the HW process the
> descriptors?
> 
> Thanks,
> Ramkumar.
> 
> --- On Tue, 11/24/09, Luis R. Rodriguez <lrodriguez@atheros.com> wrote:
> 
> 
> From: Luis R. Rodriguez <lrodriguez@atheros.com>
> Subject: Re: [ath9k-devel] ath9k:Descriptor(or Per packet)
> based TPC
> To: "Anu Krishnamoorthy" <anuramku@yahoo.com>
> Cc: "ath9k-devel at lists.ath9k.org" <ath9k-devel@lists.ath9k.org>
> Date: Tuesday, November 24, 2009, 12:29
>  PM
> 
> 
> On Tue, Nov 24, 2009 at 09:00:58AM -0800, Anu
> Krishnamoorthy wrote:
> > Hi,
> > 
> > I had implemented descriptor based TPC(per packet TPC)
> for ath9k by setting the various TxPower control fields
> within the Tx Descriptor (set11n_txdesc) for the Tx frames.
> From my testing, for some reason the Tx power values present
> in the descriptor are not applied by the hardware(I am using
> ar5416 based card). In contrast, if "iwconfig
> txpower" (in spite of the known bug) is used(forced to
> apply by down/up'ing the interface) the power change is
> noticed from the sniffer.
> >? ? ???Is any additional
> setup(transmit queue, txdesc interrupt or hardware setup)
> needs to be done to force the hardware read and process the
> tx descriptors? Appreciate if any one could shed more light
> on it or share their own experience if they had tried to
> implement this feature.
> > 
> > Thanks,
> > Ramkumar.
> 
> The tx power
>  setting was just set on the sc struct, we likely need a
> reset so
> that when tx power is changed it actually takes effect.
> There may be an easier
> way but I haven't had time to look at this yet.
> 
> ? Luis
> 
> 
> 
> ? ? ? 
> _______________________________________________
> ath9k-devel mailing list
> ath9k-devel at lists.ath9k.org
> https://lists.ath9k.org/mailman/listinfo/ath9k-devel
> 
> 
> 
>