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=-8.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 34B36C433F1 for ; Mon, 13 Jul 2020 18:07:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 191E6207BC for ; Mon, 13 Jul 2020 18:07:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="ZlOJ0Uv+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730005AbgGMSHm (ORCPT ); Mon, 13 Jul 2020 14:07:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35248 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729689AbgGMSHl (ORCPT ); Mon, 13 Jul 2020 14:07:41 -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 92F5EC061755 for ; Mon, 13 Jul 2020 11:07:41 -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=5YlKT2b8lTqdDv2oqgS+zSsmsFQlOewH1d33toTznyw=; b=ZlOJ0Uv+iWglrZ0IdoXSRMVNM rdnqfgrPUXs6d4YXl3Vkjs5BX3KJKtZtoTPa1lv5wH60ti6iyM0r9f9GzUybRf1OJsu5pSc/+PCC9 TMyD2QJuE1O+fi+tVieJUYewY1nPIkLSDTS8Dh6VXRZ84BNVZuOhYXAy7PTEtAMtLdpD5BJZkDQpP g9B4CUhx1M9OecMH13KxAYMWi5gwpz/xgh/XhBprLVPm+WyhX8wSLVJ2Cu/SuW0Y+t9+ED+Rpx+jV 1kiqfH0wmrr8TUsVxQOXLDvkZeZSAmSZQfyBOkjCI07/05A/NWqKNeadi2F+GnYAjXZlypQ7uAT2b eSRoUdsqw==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:39070) by pandora.armlinux.org.uk with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1jv2ra-0004D0-Dx; Mon, 13 Jul 2020 19:07:38 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.92) (envelope-from ) id 1jv2rZ-0006Tn-K3; Mon, 13 Jul 2020 19:07:37 +0100 Date: Mon, 13 Jul 2020 19:07:37 +0100 From: Russell King - ARM Linux admin To: Gregory CLEMENT Cc: Andrew Lunn , Jason Cooper , devicetree@vger.kernel.org, Kishon Vijay Abraham I , Vinod Koul , Rob Herring , linux-arm-kernel@lists.infradead.org, Sebastian Hesselbarth Subject: Re: [PATCH 2/2] phy: armada-38x: fix NETA lockup when repeatedly switching speeds Message-ID: <20200713180737.GU1551@shell.armlinux.org.uk> References: <20200630160452.GD1551@shell.armlinux.org.uk> <20200701065727.GY2599@vkoul-mobl> <20200710151921.GJ1551@shell.armlinux.org.uk> <20200713061846.GE34333@vkoul-mobl> <87365v5svd.fsf@FE-laptop> <20200713172140.GT1551@shell.armlinux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200713172140.GT1551@shell.armlinux.org.uk> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Mon, Jul 13, 2020 at 06:21:40PM +0100, Russell King - ARM Linux admin wrote: > On Mon, Jul 13, 2020 at 05:36:54PM +0200, Gregory CLEMENT wrote: > > Hello, > > > > > On 10-07-20, 16:19, Russell King - ARM Linux admin wrote: > > >> On Wed, Jul 01, 2020 at 12:27:27PM +0530, Vinod Koul wrote: > > >> > On 30-06-20, 17:05, Russell King wrote: > > >> > > The mvneta hardware appears to lock up in various random ways when > > >> > > repeatedly switching speeds between 1G and 2.5G, which involves > > >> > > reprogramming the COMPHY. It is not entirely clear why this happens, > > >> > > but best guess is that reprogramming the COMPHY glitches mvneta clocks > > >> > > causing the hardware to fail. It seems that rebooting resolves the > > >> > > failure, but not down/up cycling the interface alone. > > >> > > > > >> > > Various other approaches have been tried, such as trying to cleanly > > >> > > power down the COMPHY and then take it back through the power up > > >> > > initialisation, but this does not seem to help. > > >> > > > > >> > > It was finally noticed that u-boot's last step when configuring a > > >> > > COMPHY for "SGMII" mode was to poke at a register described as > > >> > > "GBE_CONFIGURATION_REG", which is undocumented in any external > > >> > > documentation. All that we have is the fact that u-boot sets a bit > > >> > > corresponding to the "SGMII" lane at the end of COMPHY initialisation. > > >> > > > > >> > > Experimentation shows that if we clear this bit prior to changing the > > >> > > speed, and then set it afterwards, mvneta does not suffer this problem > > >> > > on the SolidRun Clearfog when switching speeds between 1G and 2.5G. > > >> > > > > >> > > This problem was found while script-testing phylink. > > >> > > > > >> > > Signed-off-by: Russell King > > >> > > --- > > >> > > arch/arm/boot/dts/armada-38x.dtsi | 3 +- > > >> > > > >> > lgtm, i need ack for dts parts before I can apply this > > >> > > >> I'm not sure what the situation is for Bootlin, but they don't seem to > > >> be very responsive right now (covid related?) > > >> > > >> What I know from what I've been party to on netdev is that Bootlin > > >> sent a patch for the MVPP2 driver, and the very next day someone > > >> reported that the patch caused a bug. Unfortunately, the patch got > > >> picked up anyway, but there was no response from Bootlin. After a > > >> month or so, -final was released containing this patch, so now it > > >> had become a regression - and still no response from Bootlin. > > >> > > >> Eventually the bug got fixed - not because Bootlin fixed it, but > > >> because I ended up spending the time researching how that part of > > >> the network driver worked, diagnosing what was going on, and > > >> eventually fixing it in the most obvious way - but it's not clear > > >> that the fix was the right approach. Bootlin never commented. See > > >> 3138a07ce219 ("net: mvpp2: fix RX hashing for non-10G ports"). > > >> > > >> So, I think we have to assume that Bootlin are struggling right now, > > >> and as it's been over a week, it's unlikely that they are going to > > >> respond soon. What do you think we should do? > > >> > > >> I also note that Rob has not responded to the DT binding change > > >> either, despite me gently prodding, and Rob processing a whole raft > > >> of DT binding stuff yesterday. > > >> > > >> I can split the DTS change from the rest of the patch, but I don't > > >> think that really helps without at least the binding change being > > >> agreed. > > > > > > I would prefer splitting, you may sent the DTS to arm arch folks if no > > > response from subarch folks > > > > Yes please could you split the patch to put the dts apart ? And if the > > binding is accepted we will apply it. > > I don't see any sign that Rob will ever review the DTS part, so I'm > at the point of just not caring about this anymore. I will carry it > in my tree, but I'm going to do nothing further. > > That means that switching speed on mvneta on the Armada 38x is can > cause the network to die, but hey, if people can't be bothered to > review, and wish to impose rules such as "you can't change anything > with DT without my express say so" which have the effect of blocking > fixes, that's really not my problem. > > So, shrug, I'm giving up with these patches. Sorry. To be clear, this is not aimed at either Vinod or Gregory. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!