From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751762AbdB0IVU (ORCPT ); Mon, 27 Feb 2017 03:21:20 -0500 Received: from mga11.intel.com ([192.55.52.93]:32492 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751564AbdB0IVR (ORCPT ); Mon, 27 Feb 2017 03:21:17 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.35,213,1484035200"; d="scan'208";a="69950707" Subject: Re: [Intel-wired-lan] [PATCH] e1000e: fix timing for 82579 Gigabit Ethernet controller To: Bernd Faust , Jeff Kirsher , intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <1487270527-4549-1-git-send-email-berndfaust@gmail.com> <923e61cf-5f95-1662-2f4c-fc146359ab48@intel.com> <0a95307e-6683-b9fe-1957-be2b0a3c441e@intel.com> From: "Neftin, Sasha" Message-ID: Date: Mon, 27 Feb 2017 10:20:54 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.6.0 MIME-Version: 1.0 In-Reply-To: <0a95307e-6683-b9fe-1957-be2b0a3c441e@intel.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/26/2017 11:08, Neftin, Sasha wrote: > On 2/19/2017 14:55, Neftin, Sasha wrote: >> On 2/16/2017 20:42, Bernd Faust wrote: >>> After an upgrade to Linux kernel v4.x the hardware timestamps of the >>> 82579 Gigabit Ethernet Controller are different than expected. >>> The values that are being read are almost four times as big as before >>> the kernel upgrade. >>> >>> The difference is that after the upgrade the driver sets the clock >>> frequency to 25MHz, where before the upgrade it was set to 96MHz. Intel >>> confirmed that the correct frequency for this network adapter is 96MHz. >>> >>> Signed-off-by: Bernd Faust >>> --- >>> drivers/net/ethernet/intel/e1000e/netdev.c | 6 ++++++ >>> 1 file changed, 6 insertions(+) >>> >>> diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c >>> b/drivers/net/ethernet/intel/e1000e/netdev.c >>> index 7017281..8b7113d 100644 >>> --- a/drivers/net/ethernet/intel/e1000e/netdev.c >>> +++ b/drivers/net/ethernet/intel/e1000e/netdev.c >>> @@ -3511,6 +3511,12 @@ s32 e1000e_get_base_timinca(struct >>> e1000_adapter *adapter, u32 *timinca) >>> >>> switch (hw->mac.type) { >>> case e1000_pch2lan: >>> + /* Stable 96MHz frequency */ >>> + incperiod = INCPERIOD_96MHz; >>> + incvalue = INCVALUE_96MHz; >>> + shift = INCVALUE_SHIFT_96MHz; >>> + adapter->cc.shift = shift + INCPERIOD_SHIFT_96MHz; >>> + break; >>> case e1000_pch_lpt: >>> if (er32(TSYNCRXCTL) & E1000_TSYNCRXCTL_SYSCFI) { >>> /* Stable 96MHz frequency */ >>> -- >>> 2.7.4 >>> _______________________________________________ >>> Intel-wired-lan mailing list >>> Intel-wired-lan@lists.osuosl.org >>> http://lists.osuosl.org/mailman/listinfo/intel-wired-lan >> >> Hello, >> >> e1000_pch2lan mac type corresponds to 82579LM and 82579V network >> adapters. System clock frequency indication (SYSCFI) for these >> devices supports both 25MHz and 96MHz frequency. By default >> TSYNCRXCTL.SYSCFI is set to 1 and that means 96MHz frequency is picked. >> >> It is better to keep the current implementation as it covers all >> options. >> >> Thanks, >> >> Sasha >> > Hello, > > During last couple of weeks I saw few complaints from community on > same timing problem with 82579. I will double check clock definition > with HW architecture. > > Sasha > > _______________________________________________ > Intel-wired-lan mailing list > Intel-wired-lan@lists.osuosl.org > http://lists.osuosl.org/mailman/listinfo/intel-wired-lan I've double checked - 82579 support 96MHz frequency only. So, let's accept this suggestion to upstream. Ack.