From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from metis.whiteo.stw.pengutronix.de (metis.whiteo.stw.pengutronix.de [185.203.201.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3B501239567 for ; Mon, 27 Oct 2025 14:50:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.203.201.7 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761576659; cv=none; b=jnoR2FT/CFD3PYKb1TC003xvAjsN+hxpvIhjmc74CcGvpFZxPoMJcMmbKRmi6zNfv/BSIe7tbEMOTYNS2TtQj4muOjQMr3Mxuu8LQbxOod0JGterlpvLsaL9Ki2rZG5/P/7eKhmfr66HeFRQr5tEiSRlclS5jXUB24DKAaZ5BDg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761576659; c=relaxed/simple; bh=YnYr+2uN9p8Wy5e6baDAXbycSnvRdc+rm4lMHQd2wCQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Fm2T1OFQjuAE7orbmBxZJn5040QxVMZSFzlT/RML1CmOMQU8lDVwd2b0GX9Gt34KxOkXOoB1++tiH20zqfSvqu8LQ889zPKePec8Zp6kiQa3E+zHcU015NaFi8Gmh+0iPjkraR04K7bLVUEdvDyOe98EpM8c6DQmvuYJSn6eBiI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de; spf=pass smtp.mailfrom=pengutronix.de; arc=none smtp.client-ip=185.203.201.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pengutronix.de Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1vDOYg-0003Tf-0O; Mon, 27 Oct 2025 15:50:54 +0100 Received: from pty.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::c5]) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1vDOYf-005j1D-1r; Mon, 27 Oct 2025 15:50:53 +0100 Received: from ore by pty.whiteo.stw.pengutronix.de with local (Exim 4.96) (envelope-from ) id 1vDOYf-003DTB-1K; Mon, 27 Oct 2025 15:50:53 +0100 Date: Mon, 27 Oct 2025 15:50:53 +0100 From: Oleksij Rempel To: Andrew Lunn Cc: "Russell King (Oracle)" , Laurent Pinchart , devicetree@vger.kernel.org, Conor Dooley , imx@lists.linux.dev, Shawn Guo , Sascha Hauer , Kieran Bingham , Daniel Scally , Pengutronix Kernel Team , Stefan Klug , Krzysztof Kozlowski , Fabio Estevam , Rob Herring , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] arm64: dts: imx8mp-debix-model-a: Disable EEE for 1000T Message-ID: References: <20251026122905.29028-1-laurent.pinchart@ideasonboard.com> <20251027100227.GE1544@pendragon.ideasonboard.com> <20251027103107.GF1544@pendragon.ideasonboard.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-Accept-Language: de,en X-Accept-Content-Type: text/plain X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: ore@pengutronix.de X-SA-Exim-Scanned: No (on metis.whiteo.stw.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: devicetree@vger.kernel.org On Mon, Oct 27, 2025 at 01:50:21PM +0100, Andrew Lunn wrote: > > > Ack. With comment in the code, why we prefer this way, in case some one > > > wont to spend time on making it work. Probably SmartEEE or some other > > > word should be used. > > > > So we have options. > > > > However, we need to get to the bottom of what caused the change of > > behaviour before we start throwing solutions at this. > > It also seems like the PHY is FUBAR. If the standard 802.3 EEE > registers are being used, a management plane is using them to > negotiate EEE with the link partner, the PHY firmware should disable > SmartEEE and only provide 802.3 EEE. > > It sounds like this PHY is not 802.3 compatible. I do not know better place to post it, so I add it here for archive. At least, it explains a reason why EEE fails. Something like this is not possible to handle on the MAC side. At same time it is hard to diagnose: In 100BASE-TX EEE mode, the link partner may drop link or loss packet when the local MAC/PHY (device) starts to transmit the “Wake” signal immediately following the “Sleep”/“Refresh” signal to exit Low-Power Idle mode and return to Active mode. Many EEE PHY link partners require a short “Quiet” (Tq) duration after receiving the “Sleep”/“Refresh” signal. Without this short Tq wait time, that is not specified in the IEEE 802.3az Standard, link drop or packet loss can occur. https://ww1.microchip.com/downloads/aemDocuments/documents/OTH/ProductDocuments/Errata/80000708B.pdf -- 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 |