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=-4.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 68F30C433E0 for ; Thu, 21 Jan 2021 04:39:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3AFFC238E2 for ; Thu, 21 Jan 2021 04:39:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727359AbhAUEjM (ORCPT ); Wed, 20 Jan 2021 23:39:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59120 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727139AbhAUEFw (ORCPT ); Wed, 20 Jan 2021 23:05:52 -0500 Received: from mail-pg1-x52b.google.com (mail-pg1-x52b.google.com [IPv6:2607:f8b0:4864:20::52b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 74503C0613C1 for ; Wed, 20 Jan 2021 20:04:55 -0800 (PST) Received: by mail-pg1-x52b.google.com with SMTP id 15so522612pgx.7 for ; Wed, 20 Jan 2021 20:04:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=Z4961jt1yqYw+6AjM3/ZcftAy8KN1wVKDXeUsQv84XQ=; b=hLW9aUbDZEMnDt3hhOer9sdZ5cKF/ujjVMVDEOFGYSmLhjsDRdIwRF6SEatQhag+lQ T/w8Dki/GX0+Yo8sE7cSTBC4ak7lo+pt3SAKo5Ts0Px3Dqst1gaqt7FAKsEfN0UPYPED 0sb82DYS1tSnMK+QHDXTa4NAw6eoWimoTsSIse9EL26rSIkj9pPk6ktksFKkQ2GyeuR6 orzO6Vi1mz66spsl0ZfpQZE/ePMi9N99kPXFFwgSQpDgGgKLeoxi8gMHjCEb1MtauZ5w IQg5iLg4EVIFpXuHLm4fc3DekKUrduXJPRxOFFjFjMT5ERuf5x2NGuysw4l/vNi6EDDg sikA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=Z4961jt1yqYw+6AjM3/ZcftAy8KN1wVKDXeUsQv84XQ=; b=kBBRqz8y0KAiGAfzHMMwMNODdr9o3ByoIuFOnHTcR63S9I4HbMVIYsFK1OZEVYIDjF LF975pGbF15YzSLqRRJsPyTjbSIb/6vVLBrcFzsNQ8py9ktRoj2oyYCS10VZC32D+JjD PBWVPhfcjhEvvbccx3HWo8SpG9s805YERvpHvYso0cH3pOOlfakkC3zrQ7XMhZ1g8BG5 33F0vi2vO7I15SJl/UHlia3v0X3L4HHQllFrDkXR4F/oaNsm+RERJjrzz+rUq5Z8rg9d 7Y4oKMlLPYkjs9icblFv6ZrSk9UxBExHTfRf1IHFo9vHK4CTwH/BX0pCYH3M9ZzJoPJ8 Mtow== X-Gm-Message-State: AOAM533r+ZZ16ovXzMJWdKZT6qOLc2orLAj3d7hy9TVS9JfwvJbIT0ts GCqGg8320yn4EPJaBoo1zCY= X-Google-Smtp-Source: ABdhPJz8FZmBmeWwQjzgEE9fIQXCaZkLesnOHFCYwp5jy8a8K1V+bC1sLZEjfLd4j9qWGeoYCoIN2g== X-Received: by 2002:a62:c301:0:b029:1b6:74fb:696e with SMTP id v1-20020a62c3010000b02901b674fb696emr12242531pfg.59.1611201894990; Wed, 20 Jan 2021 20:04:54 -0800 (PST) Received: from hoboy.vegasvil.org (c-73-241-114-122.hsd1.ca.comcast.net. [73.241.114.122]) by smtp.gmail.com with ESMTPSA id x19sm3851924pfp.207.2021.01.20.20.04.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Jan 2021 20:04:54 -0800 (PST) Date: Wed, 20 Jan 2021 20:04:51 -0800 From: Richard Cochran To: Russell King - ARM Linux admin Cc: Andrew Lunn , Heiner Kallweit , "David S. Miller" , Jakub Kicinski , netdev@vger.kernel.org Subject: Re: [PATCH net-next] net: ethtool: allow MAC drivers to override ethtool get_ts_info Message-ID: <20210121040451.GB14465@hoboy.vegasvil.org> References: <20210114125506.GC3154@hoboy.vegasvil.org> <20210114132217.GR1551@shell.armlinux.org.uk> <20210114133235.GP1605@shell.armlinux.org.uk> <20210114172712.GA13644@hoboy.vegasvil.org> <20210114173111.GX1551@shell.armlinux.org.uk> <20210114223800.GR1605@shell.armlinux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210114223800.GR1605@shell.armlinux.org.uk> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, Jan 14, 2021 at 10:38:00PM +0000, Russell King - ARM Linux admin wrote: > So, I think the only way to prevent a regression with the code as > it is today is that we _never_ support PTP on Marvell PHYs - because > doing so _will_ break the existing MVPP2 driver's implementation and > cause a regression. The situation isn't as bad as it seems. For one thing, mvpp2 incorrectly selects NETWORK_PHY_TIMESTAMPING. It really shouldn't. I'm submitting a fix soon. As long as the new PHY driver (or at least the PTP bit) depends on NETWORK_PHY_TIMESTAMPING, then that allows users who _really_ want that to enable the option at compile time. This option adds extra checks into the networking hot path, and almost everyone should avoid enabling it. > Right now, there is no option: if a PHY supports PTP, then the only > option is to use the PHYs PTP. Which is utterly rediculous. > > Unless you can see a way around it. Because I can't. I still think the original and best method is to hide the two (and with your new driver, three) esoteric PHY time stamping drivers behind a Kconfig option, and structure the code to favor PHY devices. The idea to favor the MACs, from back in July, doesn't really change the fundamental limitations that - MAC and PHY time stamping cannot work simultaneously, and - Users of PHY devices (representing a tiny minority) must enable the otherwise uninteresting NETWORK_PHY_TIMESTAMPING option at compile time. Thanks, Richard