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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 110C3C433E0 for ; Wed, 23 Dec 2020 15:50:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C366621D79 for ; Wed, 23 Dec 2020 15:50:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728323AbgLWPua (ORCPT ); Wed, 23 Dec 2020 10:50:30 -0500 Received: from vps0.lunn.ch ([185.16.172.187]:38818 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726885AbgLWPu3 (ORCPT ); Wed, 23 Dec 2020 10:50:29 -0500 Received: from andrew by vps0.lunn.ch with local (Exim 4.94) (envelope-from ) id 1ks6OM-00Dc5c-Q3; Wed, 23 Dec 2020 16:49:34 +0100 Date: Wed, 23 Dec 2020 16:49:34 +0100 From: Andrew Lunn To: Steen Hegelund Cc: "David S. Miller" , Jakub Kicinski , Rob Herring , Device Tree List , Russell King , Lars Povlsen , Bjarni Jonasson , Microchip Linux Driver Support , Alexandre Belloni , Madalin Bucur , Nicolas Ferre , Mark Einon , Masahiro Yamada , Arnd Bergmann , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [RFC PATCH v2 8/8] arm64: dts: sparx5: Add the Sparx5 switch node Message-ID: <20201223154934.GE3198262@lunn.ch> References: <20201217075134.919699-1-steen.hegelund@microchip.com> <20201217075134.919699-9-steen.hegelund@microchip.com> <20201219202448.GE3026679@lunn.ch> <20201223143124.tr2vejqgpf2qsot2@mchp-dev-shegelun> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201223143124.tr2vejqgpf2qsot2@mchp-dev-shegelun> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 23, 2020 at 03:31:24PM +0100, Steen Hegelund wrote: > On 19.12.2020 21:24, Andrew Lunn wrote: > > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > > > > > + port13: port@13 { > > > + reg = <13>; > > > + /* Example: CU SFP, 1G speed */ > > > + max-speed = <10000>; > > > > One too many 0's for 1G. > > Ah, but this is allocation for the port, not the speed. phylib will look for this property and change what the PHY advertises based on this. There are some devices with Fast Ethernet but with a 1G PHY, because they are cheaper. By setting max-speed=<100>; phylib will stop the PHY advertising 1000Base-T/Full and 1000Base-T/Half. I can imaging the same is used when the MAC can do 2.5G, but the PHY is 5G capable, etc. > This just used by the calendar module to allocate slots on the taxis > as requested. So I would say it is OK to overallocate in this case > (but you could argue it does not make much sense). Rather than misusing the max-speed property, it would be better to add a property with your specific meaning. Andrew 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=-3.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 0ED58C433DB for ; Wed, 23 Dec 2020 15:51:06 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C15F121D79 for ; Wed, 23 Dec 2020 15:51:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C15F121D79 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lunn.ch Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=4xFiwpjsrIpqPyxFX1dMbf+GPA+9ZcH70uiLqcdCKTQ=; b=LupEN5oN22RgJ0GboUeR7ZE/K mOjxooKzcVeQ2SY6QcRbWUtIfATyNM2RD89GPhjcu1J9bQiYLqI4nR7TYtr8FAMNmvzd6PEbjfyT3 FJrcr1Q0mMMKwdrnVW/hYo4ZaHwUAUO3ccJHQI5fbZALMzTRbLBuzohpIhB5DuUmptcSpahWbzi+E IlPiy+O3uW5lVR5ZfA46XlVhm29VqXoVxWJLiNDAfashyHY9j0Cds8FPB7OYYoqS9LGMNtyC83ZFM 1pPc6//BkLnz650yM7zhyP4QV1Kk6uVCNt32kPY6Ix/X5TDckfJIl/m4B3RN/g0Nq179ZViTtY7gj Ok12p6j1A==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1ks6Og-0001bC-FH; Wed, 23 Dec 2020 15:49:54 +0000 Received: from vps0.lunn.ch ([185.16.172.187]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1ks6Oe-0001a9-2c for linux-arm-kernel@lists.infradead.org; Wed, 23 Dec 2020 15:49:52 +0000 Received: from andrew by vps0.lunn.ch with local (Exim 4.94) (envelope-from ) id 1ks6OM-00Dc5c-Q3; Wed, 23 Dec 2020 16:49:34 +0100 Date: Wed, 23 Dec 2020 16:49:34 +0100 From: Andrew Lunn To: Steen Hegelund Subject: Re: [RFC PATCH v2 8/8] arm64: dts: sparx5: Add the Sparx5 switch node Message-ID: <20201223154934.GE3198262@lunn.ch> References: <20201217075134.919699-1-steen.hegelund@microchip.com> <20201217075134.919699-9-steen.hegelund@microchip.com> <20201219202448.GE3026679@lunn.ch> <20201223143124.tr2vejqgpf2qsot2@mchp-dev-shegelun> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20201223143124.tr2vejqgpf2qsot2@mchp-dev-shegelun> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201223_104952_128552_B3C59492 X-CRM114-Status: GOOD ( 17.14 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Device Tree List , Alexandre Belloni , linux-kernel@vger.kernel.org, Arnd Bergmann , Bjarni Jonasson , Madalin Bucur , netdev@vger.kernel.org, Masahiro Yamada , Russell King , Microchip Linux Driver Support , Rob Herring , linux-arm-kernel@lists.infradead.org, Mark Einon , Jakub Kicinski , "David S. Miller" , Lars Povlsen Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Dec 23, 2020 at 03:31:24PM +0100, Steen Hegelund wrote: > On 19.12.2020 21:24, Andrew Lunn wrote: > > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > > > > > + port13: port@13 { > > > + reg = <13>; > > > + /* Example: CU SFP, 1G speed */ > > > + max-speed = <10000>; > > > > One too many 0's for 1G. > > Ah, but this is allocation for the port, not the speed. phylib will look for this property and change what the PHY advertises based on this. There are some devices with Fast Ethernet but with a 1G PHY, because they are cheaper. By setting max-speed=<100>; phylib will stop the PHY advertising 1000Base-T/Full and 1000Base-T/Half. I can imaging the same is used when the MAC can do 2.5G, but the PHY is 5G capable, etc. > This just used by the calendar module to allocate slots on the taxis > as requested. So I would say it is OK to overallocate in this case > (but you could argue it does not make much sense). Rather than misusing the max-speed property, it would be better to add a property with your specific meaning. Andrew _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel