From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752145AbdBZJJ6 (ORCPT ); Sun, 26 Feb 2017 04:09:58 -0500 Received: from mga01.intel.com ([192.55.52.88]:64500 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751983AbdBZJJz (ORCPT ); Sun, 26 Feb 2017 04:09:55 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.35,207,1484035200"; d="scan'208";a="70281014" 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> From: "Neftin, Sasha" Message-ID: <0a95307e-6683-b9fe-1957-be2b0a3c441e@intel.com> Date: Sun, 26 Feb 2017 11:08:08 +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: <923e61cf-5f95-1662-2f4c-fc146359ab48@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 2/19/2017 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