From patchwork Mon Nov 29 18:17:44 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: 518929 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 6A074C433EF for ; Mon, 29 Nov 2021 22:34:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233560AbhK2Wh5 (ORCPT ); Mon, 29 Nov 2021 17:37:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33704 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233463AbhK2Wh1 (ORCPT ); Mon, 29 Nov 2021 17:37:27 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 92E19C127B6C; Mon, 29 Nov 2021 10:29:11 -0800 (PST) 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 59A16B815AE; Mon, 29 Nov 2021 18:29:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8674AC53FC7; Mon, 29 Nov 2021 18:29:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1638210549; bh=v5jZUFqVFVOKMQhLN9SZvmpfgTrZzBxNCJl37Olwrfk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VPKW3Ou1RYe1tnOgqhxpUH23sE4asBsycC6Te2Z1gx82T3FqhSla0K3maADdsZwgB QizGNJ40J5TyV/FLI+bfgxNz/lQ3q7pkk0RuUwNpiLOyzSp+OIXoME+JE8Vo+IbUZn Ec5pttepmQcDdRGm8jj43itSbSZWhtL/xE2/87R4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Joel Stanley , Dylan Hung , Andrew Lunn , "Russell King (Oracle)" , Jakub Kicinski Subject: [PATCH 5.10 033/121] mdio: aspeed: Fix "Link is Down" issue Date: Mon, 29 Nov 2021 19:17:44 +0100 Message-Id: <20211129181712.759155094@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211129181711.642046348@linuxfoundation.org> References: <20211129181711.642046348@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Dylan Hung commit 9dbe33cf371bd70330858370bdbc35c7668f00c3 upstream. The issue happened randomly in runtime. The message "Link is Down" is popped but soon it recovered to "Link is Up". The "Link is Down" results from the incorrect read data for reading the PHY register via MDIO bus. The correct sequence for reading the data shall be: 1. fire the command 2. wait for command done (this step was missing) 3. wait for data idle 4. read data from data register Cc: stable@vger.kernel.org Fixes: f160e99462c6 ("net: phy: Add mdio-aspeed") Reviewed-by: Joel Stanley Signed-off-by: Dylan Hung Reviewed-by: Andrew Lunn Reviewed-by: Russell King (Oracle) Link: https://lore.kernel.org/r/20211125024432.15809-1-dylan_hung@aspeedtech.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- drivers/net/mdio/mdio-aspeed.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/drivers/net/mdio/mdio-aspeed.c +++ b/drivers/net/mdio/mdio-aspeed.c @@ -61,6 +61,13 @@ static int aspeed_mdio_read(struct mii_b iowrite32(ctrl, ctx->base + ASPEED_MDIO_CTRL); + rc = readl_poll_timeout(ctx->base + ASPEED_MDIO_CTRL, ctrl, + !(ctrl & ASPEED_MDIO_CTRL_FIRE), + ASPEED_MDIO_INTERVAL_US, + ASPEED_MDIO_TIMEOUT_US); + if (rc < 0) + return rc; + rc = readl_poll_timeout(ctx->base + ASPEED_MDIO_DATA, data, data & ASPEED_MDIO_DATA_IDLE, ASPEED_MDIO_INTERVAL_US,