From mboxrd@z Thu Jan 1 00:00:00 1970 From: Timur Tabi Subject: Re: [PATCH 0/2] at803x: don't power-down SGMII link Date: Tue, 25 Oct 2016 12:31:21 -0500 Message-ID: <580F96E9.8090208@codeaurora.org> References: <1477305654-11328-1-git-send-email-zefir.kurtisi@neratec.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: andrew@lunn.ch, f.fainelli@gmail.com To: Zefir Kurtisi , netdev@vger.kernel.org Return-path: Received: from smtp.codeaurora.org ([198.145.29.96]:50551 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S938295AbcJYRbX (ORCPT ); Tue, 25 Oct 2016 13:31:23 -0400 In-Reply-To: <1477305654-11328-1-git-send-email-zefir.kurtisi@neratec.com> Sender: netdev-owner@vger.kernel.org List-ID: Zefir Kurtisi wrote: > In a device where the ar8031 operates in SGMII mode, we > observed that after a suspend-resume cycle in very rare > cases the copper side autonegotiation secceeds but the > SGMII side fails to come up. > > As a work-around, a patch was provided that on suspend and > resume powers the SGMII link down and up along with the > copper side. This fixed the observed failure, but > introduced a regression Timur Tabi observed: once the SGMII > is powered down, the PHY is inaccessible by the CPU and > with that e.g. can't be re-initialized after suspend. > > Since the original issue could not be reproduced by others, > this series provides an alternative handling: > * the first patch reverts the prvious fix that powers down > SGMII > * the second patch adds double-checking for the observed > failure condition > > Zefir Kurtisi (2): > Revert "at803x: fix suspend/resume for SGMII link" > at803x: double check SGMII side autoneg Tested-by: Timur Tabi With these patches, the problem I was seeing no longer occurs, and the new code does not appear to break anything. As before, I still have never seen the original problem, but this patchset seems to work for both of us. -- Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.