Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754387AbbGIVbi (ORCPT ); Thu, 9 Jul 2015 17:31:38 -0400 Received: from smtp49.i.mail.ru ([94.100.177.109]:45766 "EHLO smtp49.i.mail.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754254AbbGIVba (ORCPT ); Thu, 9 Jul 2015 17:31:30 -0400 Subject: Re: [PATCH 2/2] mvneta: use inband status only when link type is "auto" To: Florian Fainelli References: <559EB0A4.5080101@list.ru> <559EB22E.7070607@list.ru> <559EBAFE.6040705@gmail.com> <559ED8F1.7050609@list.ru> <559EE423.9060503@gmail.com> Cc: Linux kernel , Sebastien Rannou , Arnaud Ebalard , Stas Sergeev , Thomas Petazzoni , netdev , stable@vger.kernel.org From: Stas Sergeev Message-ID: <559EE82A.60505@list.ru> Date: Fri, 10 Jul 2015 00:31:22 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.0.1 MIME-Version: 1.0 In-Reply-To: <559EE423.9060503@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-Spam: Not detected X-Mras: Ok Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2155 Lines: 48 10.07.2015 00:14, Florian Fainelli пишет: > On 09/07/15 13:26, Stas Sergeev wrote: >> 09.07.2015 21:18, Florian Fainelli пишет: >>> On 09/07/15 10:41, Stas Sergeev wrote: >>>> The commit 898b2970e2c9 ("mvneta: implement SGMII-based in-band link >>>> state >>>> signaling") implemented the link parameters auto-negotiation >>>> unconditionally. >>>> Unfortunately it appears that some HW that implements SGMII protocol, >>>> doesn't generate the inband status, so it is not possible to >>>> auto-negotiate >>>> anything with such HW. >>> What is the purpose of using the in-band status in the first place if >>> you end-up having to specify a 'fixed-link' property which contains most >>> of the link parameters: speed, duplex etc...? >> You don't have to. >> My config from today is as simple as: >> >> fixed-link { >> link = "auto"; >> }; >> >> and that's all. >> Without my today's patch, only 'speed' is a mandatory - not too much. > That makes me think that 'fixed-link' is not exactly what you want then, > you would probably want something like "marvell,use-in-band-status" or > something like this. It could be a more generic property that is not > Marvell specific after all, that would be fine. I think there is some confusion around fixed-link, because of its name. This is what fixed-link is: --- Some Ethernet MACs have a "fixed link", and are not connected to a normal MDIO-managed PHY device. --- A bit vague, but to me it means "non-MDIO", and that's all. If we make it like "marvell,use-in-band-status", then it will suddenly cancel everything in a fixed-link definition, which is non obvious. Or, if we make it so that fixed-link def is not needed in presence of "marvell,use-in-band-status", then this "marvell,use-in-band-status" will have to silently enable the fixed-phy driver the way fixed-link does. If we just view fixed-link as non-MDIO link, then everything fits, IMHO. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/