Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764042AbdDSOGA (ORCPT ); Wed, 19 Apr 2017 10:06:00 -0400 Received: from mail-lf0-f65.google.com ([209.85.215.65]:34620 "EHLO mail-lf0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1763995AbdDSOF5 (ORCPT ); Wed, 19 Apr 2017 10:05:57 -0400 Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 9.3 \(3124\)) Subject: Re: [PATCH] net: phy: fix auto-negotiation stall due to unavailable interrupt From: Alexander Kochetkov In-Reply-To: <1492609604-16359-1-git-send-email-al.kochet@gmail.com> Date: Wed, 19 Apr 2017 17:05:53 +0300 Message-Id: <24E19B31-CCD8-4032-B17B-D226D4DB881D@gmail.com> References: <1492609604-16359-1-git-send-email-al.kochet@gmail.com> To: Florian Fainelli , netdev@vger.kernel.org, linux-kernel@vger.kernel.org X-Mailer: Apple Mail (2.3124) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id v3JE64sF014348 Content-Length: 2094 Lines: 51 Just found similar problem fixed in another PHY. See commit 99f81afc139c ("phy: micrel: Disable auto negotiation on startup») > 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 >