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=-5.2 required=3.0 tests=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 9706CC2BB55 for ; Wed, 15 Apr 2020 12:43:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7BDDA2074F for ; Wed, 15 Apr 2020 12:43:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S370137AbgDOMnx (ORCPT ); Wed, 15 Apr 2020 08:43:53 -0400 Received: from mx2.suse.de ([195.135.220.15]:58698 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S370090AbgDOMnr (ORCPT ); Wed, 15 Apr 2020 08:43:47 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id ED032AC11; Wed, 15 Apr 2020 12:43:43 +0000 (UTC) Received: by unicorn.suse.cz (Postfix, from userid 1000) id B1379E16A6; Wed, 15 Apr 2020 14:43:43 +0200 (CEST) Date: Wed, 15 Apr 2020 14:43:43 +0200 From: Michal Kubecek To: netdev@vger.kernel.org Cc: Oleksij Rempel , Andrew Lunn , "David S. Miller" , Florian Fainelli , Heiner Kallweit , Jakub Kicinski , Jonathan Corbet , David Jander , kernel@pengutronix.de, linux-kernel@vger.kernel.org, Russell King , mkl@pengutronix.de, Marek Vasut Subject: Re: [PATCH v1] ethtool: provide UAPI for PHY master/slave configuration. Message-ID: <20200415124343.GZ3141@unicorn.suse.cz> References: <20200415121209.12197-1-o.rempel@pengutronix.de> <20200415121940.2du33zckvayfqjrb@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200415121940.2du33zckvayfqjrb@pengutronix.de> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 15, 2020 at 02:19:40PM +0200, Oleksij Rempel wrote: > Cc: Marek Vasut > > On Wed, Apr 15, 2020 at 02:12:09PM +0200, Oleksij Rempel wrote: > > This UAPI is needed for BroadR-Reach 100BASE-T1 devices. Due to lack of > > auto-negotiation support, we needed to be able to configure the > > MASTER-SLAVE role of the port manually or from an application in user > > space. > > > > The same UAPI can be used for 1000BASE-T or MultiGBASE-T devices to > > force MASTER or SLAVE role. See IEEE 802.3-2018: > > 22.2.4.3.7 MASTER-SLAVE control register (Register 9) > > 22.2.4.3.8 MASTER-SLAVE status register (Register 10) > > 40.5.2 MASTER-SLAVE configuration resolution > > 45.2.1.185.1 MASTER-SLAVE config value (1.2100.14) > > 45.2.7.10 MultiGBASE-T AN control 1 register (Register 7.32) > > > > The MASTER-SLAVE role affects the clock configuration: > > > > ------------------------------------------------------------------------------- > > When the PHY is configured as MASTER, the PMA Transmit function shall > > source TX_TCLK from a local clock source. When configured as SLAVE, the > > PMA Transmit function shall source TX_TCLK from the clock recovered from > > data stream provided by MASTER. > > > > iMX6Q KSZ9031 XXX > > ------\ /-----------\ /------------\ > > | | | | | > > MAC |<----RGMII----->| PHY Slave |<------>| PHY Master | > > |<--- 125 MHz ---+-<------/ | | \ | > > ------/ \-----------/ \------------/ > > ^ > > \-TX_TCLK > > > > ------------------------------------------------------------------------------- > > > > Since some clock or link related issues are only reproducible in a > > specific MASTER-SLAVE-role, MAC and PHY configuration, it is beneficial > > to provide generic (not 100BASE-T1 specific) interface to the user space > > for configuration flexibility and trouble shooting. > > > > Signed-off-by: Oleksij Rempel > > --- [...] > > +/* Port mode */ > > +#define PORT_MODE_MASTER 0x00 > > +#define PORT_MODE_SLAVE 0x01 > > +#define PORT_MODE_MASTER_FORCE 0x02 > > +#define PORT_MODE_SLAVE_FORCE 0x03 > > +#define PORT_MODE_UNKNOWN 0xff Shouldn't 0 rather be something like PORT_MODE_UNSUPPORTED or PORT_MODE_NONE? If I see correctly, all drivers not setting the new field (which would be all drivers right now and almost all later) will leave the value at 0 which would be interpreted as PORT_MODE_MASTER. Michal