Return-path: Received: from mga14.intel.com ([143.182.124.37]:31293 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752398AbZEESpe convert rfc822-to-8bit (ORCPT ); Tue, 5 May 2009 14:45:34 -0400 From: "Cahill, Ben M" To: Maxim Levitsky CC: iwlwifi maling list , linux-wireless Date: Tue, 5 May 2009 11:45:33 -0700 Subject: RE: [ipw3945-devel] IWL3945 always reports noise levels of -127 Message-ID: <02B3067C068D0549A8CCFCB17D4D318B3569A467@orsmsx502.amr.corp.intel.com> References: <1241213459.7082.54.camel@maxim-laptop> <02B3067C068D0549A8CCFCB17D4D318B3569A43A@orsmsx502.amr.corp.intel.com> <1241463816.4816.1.camel@maxim-laptop> <02B3067C068D0549A8CCFCB17D4D318B3569A442@orsmsx502.amr.corp.intel.com> <1241535034.4816.20.camel@maxim-laptop> <1241540190.4816.25.camel@maxim-laptop> In-Reply-To: <1241540190.4816.25.camel@maxim-laptop> Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: Excellent information. Thank you. We just issued new 3945 uCode within the past week or two ... Is that also showing the problem (noise_diff = 0)? -- Ben -- >-----Original Message----- >From: Maxim Levitsky [mailto:maximlevitsky@gmail.com] >Sent: Tuesday, May 05, 2009 12:17 PM >To: Cahill, Ben M >Cc: iwlwifi maling list; linux-wireless >Subject: RE: [ipw3945-devel] IWL3945 always reports noise >levels of -127 > >On Tue, 2009-05-05 at 17:50 +0300, Maxim Levitsky wrote: >> On Mon, 2009-05-04 at 12:27 -0700, Cahill, Ben M wrote: >> > >> > >-----Original Message----- >> > >From: Maxim Levitsky [mailto:maximlevitsky@gmail.com] >> > >Sent: Monday, May 04, 2009 3:04 PM >> > >To: Cahill, Ben M >> > >Cc: iwlwifi maling list; linux-wireless >> > >Subject: RE: [ipw3945-devel] IWL3945 always reports noise >> > >levels of -127 >> > > >> > >On Mon, 2009-05-04 at 11:53 -0700, Cahill, Ben M wrote: >> > >> When one of our devices cannot figure out what the actual >> > >noise level is, it reports -127. >> > >> >> > >> Newer devices are better at old devices at figuring noise >> > >level. IIRC, 3945 cannot figure noise for CCK signals, and >> > >may not be possible with OFDM as well. >> > > >> > >Why then it did work on older kernel ? >> > >(and noise levels seemed to be correct) >> > >> > Hmmm, good point, and I don't know the answer! :-( >> > >> >> And I do know it now (this is what I suspected...) >> This is firmware issue. >> >> I forced the driver to use older firmware iwlwifi-3945-1.ucode, >> and noise levels are back. > > >Indeed old microcode reports values like that: >rssi:017 agc:000 sig_avg:5437 noise_diff:580 > > >New microcode reports this instead: >rssi:018 agc:000 sig_avg:140 noise_diff:000 > > >noise_diff is always zero now, and range for sig_avg changed. > >I also noticed that with older firmware I couldn't set the tx speed >Thus what recently fixed it was a firmware update! >(But in both cases OFDM rated were used) > >Thats all nothing to debug any more here. > > >Best regards, > Maxim Levitsky > >