From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-11.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A03DFC4727C for ; Tue, 29 Sep 2020 13:46:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3E3702145D for ; Tue, 29 Sep 2020 13:46:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730173AbgI2Nqs (ORCPT ); Tue, 29 Sep 2020 09:46:48 -0400 Received: from mga14.intel.com ([192.55.52.115]:8848 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728844AbgI2Nqr (ORCPT ); Tue, 29 Sep 2020 09:46:47 -0400 IronPort-SDR: fKqRNYl7Fhl8G2c5lqipSikYiCTek2YOl+1NIK+g3Ga6I/B6/QL4Y5dYYCt8T/M/qP+/rUMo5q cUTJgfkCEoeA== X-IronPort-AV: E=McAfee;i="6000,8403,9758"; a="161418079" X-IronPort-AV: E=Sophos;i="5.77,318,1596524400"; d="scan'208";a="161418079" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Sep 2020 06:46:46 -0700 IronPort-SDR: AnLD/hb4ZUSN/O4/KI3cFW1g9XmdnMF33JBCsdvTWyRZgyL40UV1A1yjcz7yR3+DWai/ay+0NR t7NN2pFiIR8w== X-IronPort-AV: E=Sophos;i="5.77,318,1596524400"; d="scan'208";a="491284425" Received: from sneftin-mobl.ger.corp.intel.com (HELO [10.251.191.104]) ([10.251.191.104]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Sep 2020 06:46:41 -0700 Subject: Re: [Intel-wired-lan] [PATCH v4] e1000e: Increase polling timeout on MDIC ready bit To: Kai-Heng Feng Cc: Jeff Kirsher , Andrew Lunn , "open list:NETWORKING DRIVERS" , open list , "moderated list:INTEL ETHERNET DRIVERS" , Jakub Kicinski , "David S. Miller" , "Lifshits, Vitaly" , "Nguyen, Anthony L" References: <20200924164542.19906-1-kai.heng.feng@canonical.com> <20200928083658.8567-1-kai.heng.feng@canonical.com> <469c71d5-93ac-e6c7-f85c-342b0df78a45@intel.com> <30761C6B-28B8-4464-8615-55EF3E090E07@canonical.com> From: "Neftin, Sasha" Message-ID: <345fffcd-e9f1-5881-fba1-d7313876e943@intel.com> Date: Tue, 29 Sep 2020 16:46:36 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <30761C6B-28B8-4464-8615-55EF3E090E07@canonical.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Kai-Heng, On 9/29/2020 16:31, Kai-Heng Feng wrote: > Hi Sasha, > >> On Sep 29, 2020, at 21:08, Neftin, Sasha wrote: >> >> On 9/28/2020 11:36, Kai-Heng Feng wrote: >>> We are seeing the following error after S3 resume: >>> [ 704.746874] e1000e 0000:00:1f.6 eno1: Setting page 0x6020 >>> [ 704.844232] e1000e 0000:00:1f.6 eno1: MDI Write did not complete >>> [ 704.902817] e1000e 0000:00:1f.6 eno1: Setting page 0x6020 >>> [ 704.903075] e1000e 0000:00:1f.6 eno1: reading PHY page 769 (or 0x6020 shifted) reg 0x17 >>> [ 704.903281] e1000e 0000:00:1f.6 eno1: Setting page 0x6020 >>> [ 704.903486] e1000e 0000:00:1f.6 eno1: writing PHY page 769 (or 0x6020 shifted) reg 0x17 >>> [ 704.943155] e1000e 0000:00:1f.6 eno1: MDI Error >>> ... >>> [ 705.108161] e1000e 0000:00:1f.6 eno1: Hardware Error >>> As Andrew Lunn pointed out, MDIO has nothing to do with phy, and indeed >>> increase polling iteration can resolve the issue. >>> This patch only papers over the symptom, as we don't really know the >>> root cause of the issue. The most possible culprit is Intel ME, which >>> may do its own things that conflict with software. >>> Signed-off-by: Kai-Heng Feng >>> --- >>> v4: >>> - States that this patch just papers over the symptom. >>> v3: >>> - Moving delay to end of loop doesn't save anytime, move it back. >>> - Point out this is quitely likely caused by Intel ME. >>> v2: >>> - Increase polling iteration instead of powering down the phy. >>> drivers/net/ethernet/intel/e1000e/phy.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> diff --git a/drivers/net/ethernet/intel/e1000e/phy.c b/drivers/net/ethernet/intel/e1000e/phy.c >>> index e11c877595fb..e6d4acd90937 100644 >>> --- a/drivers/net/ethernet/intel/e1000e/phy.c >>> +++ b/drivers/net/ethernet/intel/e1000e/phy.c >>> @@ -203,7 +203,7 @@ s32 e1000e_write_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 data) >>> * Increasing the time out as testing showed failures with >>> * the lower time out >>> */ >>> - for (i = 0; i < (E1000_GEN_POLL_TIMEOUT * 3); i++) { >>> + for (i = 0; i < (E1000_GEN_POLL_TIMEOUT * 10); i++) { >> As we discussed (many threads) - AMT/ME systems not supported on Linux as properly. I do not think increasing polling iteration will solve the problem. Rather mask it. > > I am aware of the status quo of no proper support on Intel ME. > >> I prefer you check option to disable ME vi BIOS on your system. > > We can't ask user to change the BIOS to accommodate Linux. So before a proper solution comes out, masking the problem is good enough for me. > Until then, I'll carry it as a downstream distro patch. What will you do with system that even after increasing polling time will run into HW error? > > Kai-Heng > >>> udelay(50); >>> mdic = er32(MDIC); >>> if (mdic & E1000_MDIC_READY) >> Thanks, >> Sasha > Thanks, Sasha