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 smtp1.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2017DC636D3 for ; Mon, 6 Feb 2023 16:29:08 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id CEAD881852; Mon, 6 Feb 2023 16:29:07 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org CEAD881852 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=osuosl.org; s=default; t=1675700947; bh=WfOPIYv2cg9ZwbrxLu6r6vlxxjPHuVCd4frOHxB1vgI=; h=Date:From:To:References:In-Reply-To:Subject:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: Cc:From; b=mmRCb1R1T4HegR/7joFAMQJjjwSmFzVbjCNqYipVh13jNsxjhkxRqbB2dT95/MEhW 4nLOUiRCWLP1BfBMhAUC5bUmpmqK5QZBwFnwsvKG/vHI8LhX8G5rC/CZnhrh4eYsIR CEF0Aaa8t6f9Fn0B+JboSmN9s24zkA5Z8ju0B7HZPesBoBl+VG+9okrbbUlGPvueAW 4Lh3uQiwqgSNXZHIMWOol8zbswYaWvG21yNFCs8daeeRqxVLNjao0M6tWDKWL8rdCh boogsriQSRYY4Wflusz5nRwdjJvW5wMy01rk0La2AydRR1Dy6x4Uhl5SKreP+WYSWQ ezKwvRxJn80pA== X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id R455AnwarAJX; Mon, 6 Feb 2023 16:29:05 +0000 (UTC) Received: from ash.osuosl.org (ash.osuosl.org [140.211.166.34]) by smtp1.osuosl.org (Postfix) with ESMTP id 4DDEA81886; Mon, 6 Feb 2023 16:29:05 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org 4DDEA81886 Received: from smtp2.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by ash.osuosl.org (Postfix) with ESMTP id A45321BF35E for ; Mon, 6 Feb 2023 05:47:48 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id 89D3C400DD for ; Mon, 6 Feb 2023 05:47:48 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org 89D3C400DD X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 9N3o5cDarsao for ; Mon, 6 Feb 2023 05:47:47 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org 2E5C4400AF Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by smtp2.osuosl.org (Postfix) with ESMTPS id 2E5C4400AF for ; Mon, 6 Feb 2023 05:47:47 +0000 (UTC) Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1pOuLT-0007FS-UW; Mon, 06 Feb 2023 06:47:15 +0100 Received: from ore by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1pOuLR-0004Iw-Ji; Mon, 06 Feb 2023 06:47:13 +0100 Date: Mon, 6 Feb 2023 06:47:13 +0100 From: Oleksij Rempel To: Vladimir Oltean Message-ID: <20230206054713.GD12366@pengutronix.de> References: <20230201145845.2312060-1-o.rempel@pengutronix.de> <20230204001332.dd4oq4nxqzmuhmb2@skbuf> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20230204001332.dd4oq4nxqzmuhmb2@skbuf> X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-Accept-Language: de,en X-Accept-Content-Type: text/plain User-Agent: Mutt/1.10.1 (2018-07-13) X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: ore@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: intel-wired-lan@lists.osuosl.org X-Mailman-Approved-At: Mon, 06 Feb 2023 16:29:04 +0000 Subject: Re: [Intel-wired-lan] [PATCH net-next v4 00/23] net: add EEE support for KSZ9477 and AR8035 with i.MX6 X-BeenThere: intel-wired-lan@osuosl.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Wired Ethernet Linux Kernel Driver Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Woojung Huh , Andrew Lunn , Arun.Ramadoss@microchip.com, Florian Fainelli , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Vivien Didelot , Eric Dumazet , Paolo Abeni , Wei Fang , kernel@pengutronix.de, intel-wired-lan@lists.osuosl.org, Jakub Kicinski , UNGLinuxDriver@microchip.com, "David S. Miller" , Heiner Kallweit Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-wired-lan-bounces@osuosl.org Sender: "Intel-wired-lan" On Sat, Feb 04, 2023 at 02:13:32AM +0200, Vladimir Oltean wrote: > On Wed, Feb 01, 2023 at 03:58:22PM +0100, Oleksij Rempel wrote: > > With this patch series we provide EEE control for KSZ9477 family of switches and > > AR8035 with i.MX6 configuration. > > According to my tests, on a system with KSZ8563 switch and 100Mbit idle link, > > we consume 0,192W less power per port if EEE is enabled. > > What is the code flow through the kernel with EEE? I wasn't able to find > a good explanation about it. > > Is it advertised by default, if supported? I guess phy_advertise_supported() > does that. Ack. > But is that desirable? Doesn't EEE cause undesired latency for MAC-level > PTP timestamping on an otherwise idle link? Theoretically, MAC controls Low Power Idle states and even with some "Wake" latency should be fully aware of actual ingress and egress time stamps. Practically, right now I do not have such HW to confirm it. My project is affected by EEE in different ways: - with EEE PTP has too much jitter - without EEE, the devices consumes too much power in standby mode with WoL enabled. Even switching to 10BaseT less power as 100BaseTX with EEE would do. My view is probably biased by my environment - PTP is relatively rare use case. EEE saves power (0,2W+0,2W per link in my case). Summary power saving of all devices is potentially equal to X amount of power plants. So, EEE should be enabled by default. Beside, flow control (enabled by default) affects PTP in some cases too. May be ptp4l should warn about this options? We should be able to detect it from user space. Regards, Oleksij -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ Intel-wired-lan mailing list Intel-wired-lan@osuosl.org https://lists.osuosl.org/mailman/listinfo/intel-wired-lan