From patchwork Mon Dec 20 14:34:19 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 526521 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 02855C433FE for ; Mon, 20 Dec 2021 14:43:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235770AbhLTOnA (ORCPT ); Mon, 20 Dec 2021 09:43:00 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:50094 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234811AbhLTOlg (ORCPT ); Mon, 20 Dec 2021 09:41:36 -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 ams.source.kernel.org (Postfix) with ESMTPS id F2FBBB80EA3; Mon, 20 Dec 2021 14:41:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 34D40C36AE7; Mon, 20 Dec 2021 14:41:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1640011293; bh=MyxLuDGsnsFkTNQ9KIEg117MhTda7c5Q9mee/yO3ZHA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TUcWJsk5xTsWQ2dS50ComB4MGFmwCQ6e5WjsL03lphxum4fysAWFqFhY8WehRRW9O dS3WCJYZ0pxhZaySziOMP24RlBit/jU3SOLvTAu2dsJWsDf6leh3FLAqgEMziybb1t BBs4KrZEVC6D7npOGhextl6Rz4kgjPBPRKzH+Igs= 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 4.19 26/56] ixgbe: set X550 MDIO speed before talking to PHY Date: Mon, 20 Dec 2021 15:34:19 +0100 Message-Id: <20211220143024.307234570@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211220143023.451982183@linuxfoundation.org> References: <20211220143023.451982183@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@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 9772016222c30..9277d57c4a70b 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c @@ -3391,6 +3391,9 @@ 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 ||