Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S938151AbdDSQc6 (ORCPT ); Wed, 19 Apr 2017 12:32:58 -0400 Received: from mail-wr0-f193.google.com ([209.85.128.193]:32839 "EHLO mail-wr0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S938133AbdDSQc4 (ORCPT ); Wed, 19 Apr 2017 12:32:56 -0400 Subject: Re: [PATCH] net: phy: fix auto-negotiation stall due to unavailable interrupt To: Alexander Kochetkov , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, andrew@lunn.ch, Roger Quadros , nsekhar@ti.com, kyle.roeschley@ni.com References: <1492609604-16359-1-git-send-email-al.kochet@gmail.com> <24E19B31-CCD8-4032-B17B-D226D4DB881D@gmail.com> From: Florian Fainelli Message-ID: <754f7cfe-6914-570a-d0e5-4a26b6787281@gmail.com> Date: Wed, 19 Apr 2017 09:32:51 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <24E19B31-CCD8-4032-B17B-D226D4DB881D@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2655 Lines: 69 On 04/19/2017 07:05 AM, Alexander Kochetkov wrote: > Just found similar problem fixed in another PHY. See commit 99f81afc139c > ("phy: micrel: Disable auto negotiation on startup») This specific commit was really a "this works for me, but I have not investigated what needs fixing in PHYLIB". Roger has been submitting a couple of patches to fix the same issue and yours seems to be better in that it also addresses his concerns that after his fix there was still a 1s delay (the HZ parameter to the queue_delayed_work call) being seen: http://patchwork.ozlabs.org/patch/743773/ Roger can you also test Alexander's patch? > >> 19 апр. 2017 г., в 16:46, Alexander Kochetkov написал(а): >> >> The problem I fix related to SMSC LAN8710/LAN8720 PHY handled using >> interrupts. During power-up cycle the PHY do auto-negotiation, generate >> interrupt and set BMSR_ANEGCOMPLETE flag. Interrupt is handled by PHY >> state machine but doesn't update link because PHY is in PHY_READY state. >> After some time MAC bring up and connect with PHY. It start PHY using >> phy_start(). During startup PHY change state to PHY_AN but doesn't >> set BMCR_ANRESTART flag due to genphy_config_aneg() doesn't update MII_BMCR >> because there no new to advertising. As a result, state machine wait for >> interrupt from PHY and nether get "link is up". Because BMSR_ANEGCOMPLETE >> already set the patch schedule check link without waiting interrupt. >> In case genphy_config_aneg() update MII_BMCR and set BMCR_ANRESTART >> flag, BMSR_ANEGCOMPLETE will be cleared and state machine will continue >> on auto-negotiation interrupt. >> >> Signed-off-by: Alexander Kochetkov >> --- >> drivers/net/phy/phy.c | 12 ++++++++++++ >> 1 file changed, 12 insertions(+) >> >> diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c >> index 7cc1b7d..da8f03d 100644 >> --- a/drivers/net/phy/phy.c >> +++ b/drivers/net/phy/phy.c >> @@ -1169,6 +1169,18 @@ void phy_state_machine(struct work_struct *work) >> if (phydev->irq == PHY_POLL) >> queue_delayed_work(system_power_efficient_wq, &phydev->state_queue, >> PHY_STATE_TIME * HZ); >> + >> + /* Re-schedule a PHY state machine to check PHY status because >> + * negotiation already done and aneg interrupt may not be generated. >> + */ >> + if (needs_aneg && (phydev->irq > 0) && (phydev->state == PHY_AN)) { >> + err = phy_aneg_done(phydev); >> + if (err > 0) >> + queue_delayed_work(system_power_efficient_wq, >> + &phydev->state_queue, 0); >> + if (err < 0) >> + phy_error(phydev); >> + } >> } >> >> /** >> -- >> 1.7.9.5 >> > -- Florian