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 672E4C433EF for ; Sun, 1 May 2022 11:34:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346538AbiEALiO (ORCPT ); Sun, 1 May 2022 07:38:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58438 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237006AbiEALiN (ORCPT ); Sun, 1 May 2022 07:38:13 -0400 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:32c8:5054:ff:fe00:142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CD1DD1CFFA for ; Sun, 1 May 2022 04:34:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=ndT2OoohNBLkRvLz+mc8gCuPExVVovgCugEML5NODZ4=; b=N/L3YjuSkn/XUX0i54JxnXc8PA lIeOEs7feWZYdP1/QqjZY/zKNjt3tWRSxATbaw5Nu4pRiqzCm2djquKHT/gfpAzVUi/TusT4umfJZ 36WqCrHaXxIc/qSBo+kFKOcNHhXgaEgUAgegvEdbcw3L+yv0dzHfSp27M6lqXV241Ecx1G20TpfbT p9i+BdqfA6IlsnkWISysRu9tO6GF50wlRQN5gm8OPng7ef2mZU9AM00uAgbncRhRfWoGf4QhSzcCd 7KTRZGFDgEdbisKLiISKpn5zDixZMUInFqP1GqBG41vT6rNMpm1n9o7mqBkQclPD/XKa/lZwvHvLt 3g4if8PQ==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:58476) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1nl7qg-0006DW-5U; Sun, 01 May 2022 12:34:45 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1nl7qe-0003qp-Sl; Sun, 01 May 2022 12:34:44 +0100 Date: Sun, 1 May 2022 12:34:44 +0100 From: "Russell King (Oracle)" To: Marcin Wojtas Cc: Baruch Siach , netdev , Baruch Siach Subject: Re: [PATCH] net: mvpp2: add delay at the end of .mac_prepare Message-ID: References: <2460cc37a4138d3cfb598349e78f0c5f3cfa59c7.1651071936.git.baruch@tkos.co.il> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: Russell King (Oracle) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, Apr 28, 2022 at 10:59:59AM +0200, Marcin Wojtas wrote: > Hi Baruch, > > Thank you for the patch and debug effort, however at first glance it > seems that adding delay may be a work-around and cover an actual root > cause (maybe Russell will have more input here). Please note I'm on a boat suffering diesel bug (means I'm running off limited battery power which has to last until Wednesday for more vital services, so I'm only around sporadically as the situation permits. It's basically exactly an Apollo 13 situation - everything's turned off except when absolutely required!) Early revisions of the 88x3310 firmware have problems when switching between the different MAC-side link modes. When this occurs, the PHY firmware flashes one (iirc yellow) LED rapidly and refuses to link. The answer is not to add random delays to the MAC driver, but get the firmware of the MAC updated to something way less buggy - and those early firmwares do contain a lot of bugs. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!