Return-path: Received: from mail-iw0-f174.google.com ([209.85.214.174]:45053 "EHLO mail-iw0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756484Ab0F2PUQ convert rfc822-to-8bit (ORCPT ); Tue, 29 Jun 2010 11:20:16 -0400 Received: by iwn7 with SMTP id 7so1299612iwn.19 for ; Tue, 29 Jun 2010 08:20:15 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <4C29284C.5050707@openwrt.org> References: <4C29284C.5050707@openwrt.org> Date: Tue, 29 Jun 2010 17:20:15 +0200 Message-ID: Subject: Re: ath9k: ap tsf seems random and only uses lower 24 bits or so From: =?ISO-8859-1?Q?Bj=F6rn_Smedman?= To: Felix Fietkau Cc: linux-wireless , ath9k-devel@lists.ath9k.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-wireless-owner@vger.kernel.org List-ID: 2010/6/29 Felix Fietkau : > IMHO the most likely problem source is stuck beacons. Please compile the > driver with the debug option enabled and load it with > insmod ath9k debug=0x00000100 It looks like it could be: ... Jan 1 00:06:21 OpenWrt user.debug kernel: ath: slot 2 [tsf 1986567 tsftu 1940 intval 100] vif (null) Jan 1 00:06:21 OpenWrt user.debug kernel: ath: slot 1 [tsf 2012168 tsftu 1965 intval 100] vif (null) Jan 1 00:06:21 OpenWrt user.debug kernel: ath: slot 0 [tsf 2037767 tsftu 1990 intval 100] vif 80945e70 Jan 1 00:06:21 OpenWrt user.debug kernel: ath: slot 0 [tsf 79033 tsftu 77 intval 100] vif 80945e70 Jan 1 00:06:21 OpenWrt user.debug kernel: ath: missed 1 consecutive beacons Jan 1 00:06:21 OpenWrt user.debug kernel: ath: resume beacon xmit after 1 misses Jan 1 00:06:21 OpenWrt user.debug kernel: ath: slot 3 [tsf 117790 tsftu 115 intval 100] vif (null) Jan 1 00:06:21 OpenWrt user.debug kernel: ath: slot 2 [tsf 143368 tsftu 140 intval 100] vif (null) Jan 1 00:06:21 OpenWrt user.debug kernel: ath: slot 1 [tsf 168967 tsftu 165 intval 100] vif (null) ... Jan 1 00:09:08 OpenWrt user.debug kernel: ath: slot 1 [tsf 14197768 tsftu 13865 intval 100] vif (null) Jan 1 00:09:08 OpenWrt user.debug kernel: ath: slot 0 [tsf 14223368 tsftu 13890 intval 100] vif 80945e70 Jan 1 00:09:08 OpenWrt user.debug kernel: ath: slot 3 [tsf 14248967 tsftu 13915 intval 100] vif (null) Jan 1 00:09:08 OpenWrt user.debug kernel: ath: slot 0 [tsf 79180 tsftu 77 intval 100] vif 80945e70 Jan 1 00:09:08 OpenWrt user.debug kernel: ath: missed 1 consecutive beacons Jan 1 00:09:08 OpenWrt user.debug kernel: ath: resume beacon xmit after 1 misses Jan 1 00:09:08 OpenWrt user.debug kernel: ath: slot 3 [tsf 117791 tsftu 115 intval 100] vif (null) Jan 1 00:09:08 OpenWrt user.debug kernel: ath: slot 2 [tsf 143366 tsftu 140 intval 100] vif (null) Jan 1 00:09:08 OpenWrt user.debug kernel: ath: slot 1 [tsf 168967 tsftu 165 intval 100] vif (null) Jan 1 00:09:08 OpenWrt user.debug kernel: ath: slot 0 [tsf 194567 tsftu 190 intval 100] vif 80945e70 ... What can cause a missed beacon? Are they just a "fact of life"? In any case I can't find any code that resets the tsf in this (single missed beacon) case. Will the hardware reset the tsf automatically whenever a single beacon is missed? Isn't that a bit overkill? Will it not cause problems for clients? > - Felix /Bj?rn