From patchwork Mon Nov 22 23:51:53 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Marek_Beh=C3=BAn?= X-Patchwork-Id: 12633137 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 28C96C433F5 for ; Mon, 22 Nov 2021 23:52:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232045AbhKVXzI (ORCPT ); Mon, 22 Nov 2021 18:55:08 -0500 Received: from mail.kernel.org ([198.145.29.99]:42560 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232051AbhKVXzG (ORCPT ); Mon, 22 Nov 2021 18:55:06 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7F77E600CD; Mon, 22 Nov 2021 23:51:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1637625119; bh=CR7sQcDkZMOY57zkce7NGbaNb63+1fmpmrSWlBk8QLM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BCh8RIOLdO923KetzvMcPCIngZ3TV3LrfGmGm7D5zdw0J7qiS4nXae3Yay3w/82Td ssK1cdNJ4DSjc/eC1V9cvCWQ/U4T2v4bRapQOFcRkvScDVZhzqCOYEcESNgcJEkiJO 5hjigYqTpgAK4iVuN1d9MBMO/4MTehK8VhkRRmBpfoeSo9qGb+QGAU1JGnWsGh7K29 bbl/UtTN4dnsJl2G+Op15TyVSL9hb+2QVhUl5ADE1KWqrOP7wGCASzPEMfIcxvorp8 aZoUda/OPqQQzVr4tXAgtM5BWvKLZ4PnY753GNK3/eaHeUmWz/s8GSC9EbPd/eZ4LR w+sC8A3vHsYTQ== From: =?utf-8?q?Marek_Beh=C3=BAn?= To: netdev@vger.kernel.org Cc: Russell King , Jakub Kicinski , Andrew Lunn , davem@davemloft.net, =?utf-8?q?Marek_Beh=C3=BAn?= Subject: [PATCH net 1/2] net: phylink: Force link down and retrigger resolve on interface change Date: Tue, 23 Nov 2021 00:51:53 +0100 Message-Id: <20211122235154.6392-2-kabel@kernel.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20211122235154.6392-1-kabel@kernel.org> References: <20211122235154.6392-1-kabel@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org On PHY state change the phylink_resolve() function can read stale information from the MAC and report incorrect link speed and duplex to the kernel message log. Example with a Marvell 88X3310 PHY connected to a SerDes port on Marvell 88E6393X switch: - PHY driver triggers state change due to PHY interface mode being changed from 10gbase-r to 2500base-x due to copper change in speed from 10Gbps to 2.5Gbps, but the PHY itself either hasn't yet changed its interface to the host, or the interrupt about loss of SerDes link hadn't arrived yet (there can be a delay of several milliseconds for this), so we still think that the 10gbase-r mode is up - phylink_resolve() - phylink_mac_pcs_get_state() - this fills in speed=10g link=up - interface mode is updated to 2500base-x but speed is left at 10Gbps - phylink_major_config() - interface is changed to 2500base-x - phylink_link_up() - mv88e6xxx_mac_link_up() - .port_set_speed_duplex() - speed is set to 10Gbps - reports "Link is Up - 10Gbps/Full" to dmesg Afterwards when the interrupt finally arrives for mv88e6xxx, another resolve is forced in which we get the correct speed from phylink_mac_pcs_get_state(), but since the interface is not being changed anymore, we don't call phylink_major_config() but only phylink_mac_config(), which does not set speed/duplex anymore. To fix this, we need to force the link down and trigger another resolve on PHY interface change event. Fixes: 9525ae83959b ("phylink: add phylink infrastructure") Signed-off-by: Russell King (Oracle) Signed-off-by: Marek Behún --- drivers/net/phy/phylink.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c index 3603c024109a..5b8b61daeb98 100644 --- a/drivers/net/phy/phylink.c +++ b/drivers/net/phy/phylink.c @@ -963,6 +963,7 @@ static void phylink_resolve(struct work_struct *w) struct phylink_link_state link_state; struct net_device *ndev = pl->netdev; bool mac_config = false; + bool retrigger = false; bool cur_link_state; mutex_lock(&pl->state_mutex); @@ -976,6 +977,7 @@ static void phylink_resolve(struct work_struct *w) link_state.link = false; } else if (pl->mac_link_dropped) { link_state.link = false; + retrigger = true; } else { switch (pl->cur_link_an_mode) { case MLO_AN_PHY: @@ -1000,6 +1002,15 @@ static void phylink_resolve(struct work_struct *w) /* Only update if the PHY link is up */ if (pl->phydev && pl->phy_state.link) { + /* If the interface has changed, force a + * link down event if the link isn't already + * down, and re-resolve. + */ + if (link_state.interface != + pl->phy_state.interface) { + retrigger = true; + link_state.link = false; + } link_state.interface = pl->phy_state.interface; /* If we have a PHY, we need to update with @@ -1042,7 +1053,7 @@ static void phylink_resolve(struct work_struct *w) else phylink_link_up(pl, link_state); } - if (!link_state.link && pl->mac_link_dropped) { + if (!link_state.link && retrigger) { pl->mac_link_dropped = false; queue_work(system_power_efficient_wq, &pl->resolve); } From patchwork Mon Nov 22 23:51:54 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Marek_Beh=C3=BAn?= X-Patchwork-Id: 12633139 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0148EC4332F for ; Mon, 22 Nov 2021 23:52:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232053AbhKVXzJ (ORCPT ); Mon, 22 Nov 2021 18:55:09 -0500 Received: from mail.kernel.org ([198.145.29.99]:42570 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232007AbhKVXzI (ORCPT ); Mon, 22 Nov 2021 18:55:08 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0C9436101A; Mon, 22 Nov 2021 23:51:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1637625121; bh=egm/7DenZTTEK7bHJfVrPa0M9dSi6t5o9PCmnk+J7i4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=blc41oc0wkUYjnp3CWi1e3lu4RQuwnL/CbEJmvVKt4w0TP/xvD27n1aEIXFpAAG0m KL7QNgPO7263OvU0cCQWOqOoK2c6BefDdAO/dHPxUJPsDxmIs11RTgghskg5RbBXcv DUuuiYoyZzK7cJ7+OmNBym9YhEu2mizNLOeuPzlLOqwZJMStRkndCJ6MaZhofdGmbZ Bv9uk0FTa+0eXg8qUoD0rwt20Qxr0f4kynX537oyip7bASaNT501Sr+dk82T51Jd+v QuOy9pQp8RjRJD/lR+Rt2JWtyRS1OzWl5bUkYBKHLi645Lh6cdyofjWtZFTK34gMuV tVUuxabZL2+UQ== From: =?utf-8?q?Marek_Beh=C3=BAn?= To: netdev@vger.kernel.org Cc: Russell King , Jakub Kicinski , Andrew Lunn , davem@davemloft.net, =?utf-8?q?Marek_Beh=C3=BAn?= Subject: [PATCH net 2/2] net: phylink: Force retrigger in case of latched link-fail indicator Date: Tue, 23 Nov 2021 00:51:54 +0100 Message-Id: <20211122235154.6392-3-kabel@kernel.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20211122235154.6392-1-kabel@kernel.org> References: <20211122235154.6392-1-kabel@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org On mv88e6xxx 1G/2.5G PCS, the SerDes register 4.2001.2 has the following description: This register bit indicates when link was lost since the last read. For the current link status, read this register back-to-back. Thus to get current link state, we need to read the register twice. But doing that in the link change interrupt handler would lead to potentially ignoring link down events, which we really want to avoid. Thus this needs to be solved in phylink's resolve, by retriggering another resolve in the event when PCS reports link down and previous link was up. The wrong value is read when phylink requests change from sgmii to 2500base-x mode, and link won't come up. This fixes the bug. Fixes: 9525ae83959b ("phylink: add phylink infrastructure") Signed-off-by: Russell King (Oracle) Signed-off-by: Marek Behún --- drivers/net/phy/phylink.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c index 5b8b61daeb98..c6b5d5af8817 100644 --- a/drivers/net/phy/phylink.c +++ b/drivers/net/phy/phylink.c @@ -994,6 +994,12 @@ static void phylink_resolve(struct work_struct *w) case MLO_AN_INBAND: phylink_mac_pcs_get_state(pl, &link_state); + /* The PCS may have a latching link-fail indicator. + * If the PCS link goes down, retrigger a resolve. + */ + if (!link_state.link && cur_link_state) + retrigger = true; + /* If we have a phy, the "up" state is the union of * both the PHY and the MAC */