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 X-Spam-Level: X-Spam-Status: No, score=-13.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BB33CC38A2A for ; Fri, 8 May 2020 17:42:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 91A3C2083B for ; Fri, 8 May 2020 17:42:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="l/C4GNJ3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727106AbgEHRms (ORCPT ); Fri, 8 May 2020 13:42:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49874 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726746AbgEHRms (ORCPT ); Fri, 8 May 2020 13:42:48 -0400 Received: from mail-pf1-x442.google.com (mail-pf1-x442.google.com [IPv6:2607:f8b0:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7889EC061A0C; Fri, 8 May 2020 10:42:47 -0700 (PDT) Received: by mail-pf1-x442.google.com with SMTP id 145so1300372pfw.13; Fri, 08 May 2020 10:42:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=A5et1zZ9ENnf4f4ExVYxu4DsWfEOIYFmzS6JlsqdSxQ=; b=l/C4GNJ3nNPV4iPlRSBjrRjkLIjMInNHVIvFMuosEmJQL8ArDg3Xy+Wf/tM9NudJMM WMn5YWxTvEWsc4YFtbQhNc4w/elFLk3OLRoNsCAkFXaZ6k8Snpv0I6b1ImelpM6iNbGH wP6xKd9+twYQfKkyigZEobng1qTEBEaVi9eEXuHfPP9DXCr6yo/WjVhQRu/DmyoYjWlM ZzxUJfoy+z+/lStg1XKfWTYdTDZWNhYTE/H1jFs+1BlgkJoWfdYe+rm0869/RNgoRH6U qmQKU69BfHtX5gVThGx/mfZCc8Fi3vjMPBBDj0/fJ22n/ERk3lf4g+UcDI0InwlmoJZ7 bOdA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=A5et1zZ9ENnf4f4ExVYxu4DsWfEOIYFmzS6JlsqdSxQ=; b=IOXoQmBUaMvgoeOGS9tMfIxKRt17f5xgaiQ1k9KJ4n9E3jINqzcQQtRsGoBrNN7RJ/ kNHfnanQh5i2OQ4K9ihiqNS/wg4UjibjurXJV14gnyj4PWAPg3PGMrGfeAsvZqlFBPDa gHv36HSdGsHwWHcMgUiol1PLvEM9PTQrF1ln8xgPujcazFxHxqQojZZwuPL59DSdPjlv D8stM9cSnVY5rDkkW52QltEePS8F4EonjqlQZHsyTF6P2Dp7DpnFLCSg6HIXry+RHaHm 7XGajl5vQgl6c4Pz07TgecpvhfwnNnFmPf5L3dNat9Z1pZie2l2CeL8qaHq+s6vxPRvi z8HA== X-Gm-Message-State: AGi0PubZv4/EbFDmBvuVlssEcztJu0p1ZZZ6aRdK/R1+QVC/sddSLZlI E6VGqFdE/TGBscNew0Uk+lWVyzNN X-Google-Smtp-Source: APiQypL+WvgRAksIUXHpgaPkLk6pu44dhlSk1kZJviYXqVOsaWKakNitDPrszlfF0QG6Lx4DeP5d6w== X-Received: by 2002:a63:6f07:: with SMTP id k7mr3222068pgc.274.1588959766367; Fri, 08 May 2020 10:42:46 -0700 (PDT) Received: from [10.230.188.43] ([192.19.223.252]) by smtp.gmail.com with ESMTPSA id a19sm2476134pfd.91.2020.05.08.10.42.44 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 08 May 2020 10:42:45 -0700 (PDT) Subject: Re: [PATCH net v2] net: bcmgenet: Clear ID_MODE_DIS in EXT_RGMII_OOB_CTRL when not needed To: Marek Szyprowski , Nicolas Saenz Julienne , Doug Berger , "David S. Miller" , Stefan Wahren Cc: bcm-kernel-feedback-list@broadcom.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <20200225131159.26602-1-nsaenzjulienne@suse.de> <09f9fdff-867f-687f-e5af-a4f82a75e105@gmail.com> From: Florian Fainelli Message-ID: <5f3d64c8-5b02-d697-c214-fb14bcff99ac@gmail.com> Date: Fri, 8 May 2020 10:42:43 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Firefox/68.0 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 5/7/2020 11:38 PM, Marek Szyprowski wrote: > Hi Florian, > > On 07.05.2020 17:54, Florian Fainelli wrote: >> On 5/7/2020 3:03 AM, Marek Szyprowski wrote: >>> On 07.05.2020 11:46, Marek Szyprowski wrote: >>>> On 25.02.2020 14:11, Nicolas Saenz Julienne wrote: >>>>> Outdated Raspberry Pi 4 firmware might configure the external PHY as >>>>> rgmii although the kernel currently sets it as rgmii-rxid. This makes >>>>> connections unreliable as ID_MODE_DIS is left enabled. To avoid this, >>>>> explicitly clear that bit whenever we don't need it. >>>>> >>>>> Fixes: da38802211cc ("net: bcmgenet: Add RGMII_RXID support") >>>>> Signed-off-by: Nicolas Saenz Julienne >>>> I've finally bisected the network issue I have on my RPi4 used for >>>> testing mainline builds. The bisect pointed to this patch. Once it got >>>> applied in v5.7-rc1, the networking is broken on my RPi4 in ARM32bit >>>> mode and kernel compiled from bcm2835_defconfig. I'm using u-boot to >>>> tftp zImage/dtb/initrd there. After reverting this patch network is >>>> working fine again. The strange thing is that networking works fine if >>>> kernel is compiled from multi_v7_defconfig but I don't see any obvious >>>> difference there. >>>> >>>> I'm not sure if u-boot is responsible for this break, but kernel >>>> definitely should be able to properly reset the hardware to the valid >>>> state. >>>> >>>> ... >>> Okay, I've played a bit more with this and found that enabling >>> CONFIG_BROADCOM_PHY fixes this network issue. I wonder if Genet driver >>> should simply select CONFIG_BROADCOM_PHY the same way as it selects >>> CONFIG_BCM7XXX_PHY. >> Historically GENET has been deployed with an internal PHY and this is >> still 90% of the GENET users out there on classic Broadcom STB >> platforms, not counting the 2711. For external PHYs, there is a variety >> of options here, so selecting CONFIG_BROADCOM_PHY would be just one of >> the possibilities, I would rather fix this with the bcm2835_defconfig >> and multi_v7_defconfig update. Would that work for you? > > Frankly I was surprised that the Genet driver successfully probed and > registered eth0 even when no proper PHY driver was available in the > system. It even reported the link status change, but then didn't > transfer any packets. I expected at least a runtime check and error or > warning if proper PHY is not available. > If this is really not possible, I would still advise to select proper potential PHY drivers, so users > won't be confused. It is possible to issue a warning if we find ourselves running on a BCM2711 SoC and we end-up using the Generic PHY driver, much like what r8169 does (for similar reasons): https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit/?id=f32593773549 https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit/?id=0c2006b29e5f62784c70209e71da7876267e0e2d > > The Genet driver already selects CONFIG_BCM7XXX_PHY. How common is it? GENET is a roughly 15 years old Ethernet controller that has evolved and is still being integrated into new chips, so we have probably hundreds of millions of devices out there. > Would it really hurt do the same for CONFIG_BROADCOM_PHY? I expect that > 2711 will be quite popular SoC with it soon. My problem with a select BROADCOM_PHY is that it will make it impossible for me to deselect the Broadcom PHY driver. We have probably about a hundred or so reference boards with a variety of external PHYs some Broadcom and we have managed to get them all working out of the box with the Generic PHY driver. If I cannot deselect the Broadcom PHY driver there will be RGMII regressions (much like the one you reported) which I really have no interest in solving when it can be avoided. Does the following work for you: diff --git a/drivers/net/ethernet/broadcom/Kconfig b/drivers/net/ethernet/broadcom/Kconfig index 53055ce5dfd6..8a70b9152f7c 100644 --- a/drivers/net/ethernet/broadcom/Kconfig +++ b/drivers/net/ethernet/broadcom/Kconfig @@ -69,6 +69,7 @@ config BCMGENET select BCM7XXX_PHY select MDIO_BCM_UNIMAC select DIMLIB + imply BROADCOM_PHY if ARCH_BCM2835 help This driver supports the built-in Ethernet MACs found in the Broadcom BCM7xxx Set Top Box family chipset. -- Florian