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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C064CC433EF for ; Mon, 20 Dec 2021 14:58:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238632AbhLTO6Q (ORCPT ); Mon, 20 Dec 2021 09:58:16 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:46566 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236675AbhLTOzz (ORCPT ); Mon, 20 Dec 2021 09:55:55 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 543A8611AA; Mon, 20 Dec 2021 14:55:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 38669C36AE9; Mon, 20 Dec 2021 14:55:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1640012153; bh=kDYyP6FYfVJBTPVvRIiBaAmfNJfx6oxrvIGPI2ru+yQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1wZkbe9e+WePwcODR985LRnN0uOHi0CNisEhQZBUXZ5DJE29Xcf2ez1Nll8vhQBaG rPjN/h4c+6dMT7fbHbznCV9Ub3lOfDpKJ0ErPL5Fzg8OksISNqtxDJM8iXHZqNjlZW qP22WB+1/wyfDYDS7Mys/YeMGmIBXrTzpQllPWW0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Cyril Novikov , Andrew Lunn , Tony Nguyen , Sasha Levin Subject: [PATCH 5.15 098/177] ixgbe: set X550 MDIO speed before talking to PHY Date: Mon, 20 Dec 2021 15:34:08 +0100 Message-Id: <20211220143043.391512800@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211220143040.058287525@linuxfoundation.org> References: <20211220143040.058287525@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Cyril Novikov [ Upstream commit bf0a375055bd1afbbf02a0ef45f7655da7b71317 ] The MDIO bus speed must be initialized before talking to the PHY the first time in order to avoid talking to it using a speed that the PHY doesn't support. This fixes HW initialization error -17 (IXGBE_ERR_PHY_ADDR_INVALID) on Denverton CPUs (a.k.a. the Atom C3000 family) on ports with a 10Gb network plugged in. On those devices, HLREG0[MDCSPD] resets to 1, which combined with the 10Gb network results in a 24MHz MDIO speed, which is apparently too fast for the connected PHY. PHY register reads over MDIO bus return garbage, leading to initialization failure. Reproduced with Linux kernel 4.19 and 5.15-rc7. Can be reproduced using the following setup: * Use an Atom C3000 family system with at least one X552 LAN on the SoC * Disable PXE or other BIOS network initialization if possible (the interface must not be initialized before Linux boots) * Connect a live 10Gb Ethernet cable to an X550 port * Power cycle (not reset, doesn't always work) the system and boot Linux * Observe: ixgbe interfaces w/ 10GbE cables plugged in fail with error -17 Fixes: e84db7272798 ("ixgbe: Introduce function to control MDIO speed") Signed-off-by: Cyril Novikov Reviewed-by: Andrew Lunn Signed-off-by: Tony Nguyen Signed-off-by: Sasha Levin --- drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c index 9724ffb165189..e4b50c7781ffa 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c @@ -3405,6 +3405,9 @@ static s32 ixgbe_reset_hw_X550em(struct ixgbe_hw *hw) /* flush pending Tx transactions */ ixgbe_clear_tx_pending(hw); + /* set MDIO speed before talking to the PHY in case it's the 1st time */ + ixgbe_set_mdio_speed(hw); + /* PHY ops must be identified and initialized prior to reset */ status = hw->phy.ops.init(hw); if (status == IXGBE_ERR_SFP_NOT_SUPPORTED || -- 2.33.0