From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753351AbaH2SYe (ORCPT ); Fri, 29 Aug 2014 14:24:34 -0400 Received: from mail-pd0-f178.google.com ([209.85.192.178]:47325 "EHLO mail-pd0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752528AbaH2SYc (ORCPT ); Fri, 29 Aug 2014 14:24:32 -0400 Message-ID: <5400C53D.70501@gmail.com> Date: Fri, 29 Aug 2014 11:23:57 -0700 From: Florian Fainelli User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.0 MIME-Version: 1.0 To: Jason Gunthorpe , =?UTF-8?B?U8O2cmVu?= =?UTF-8?B?IEJyaW5rbWFubg==?= CC: =?UTF-8?B?QW5kcmVhcyBGw6RyYmVy?= , Mark Rutland , "devicetree@vger.kernel.org" , Russell King , Pawel Moll , Ian Campbell , Michal Simek , "linux-kernel@vger.kernel.org" , Rob Herring , Kumar Gala , "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH 3/3] ARM: zynq: DT: Add Ethernet phys References: <1408550219-19825-3-git-send-email-soren.brinkmann@xilinx.com> <5a7b6f57-b6c0-4fb3-af0d-d403277c0207@BN1AFFO11FD045.protection.gbl> <53F5D8D9.7040604@suse.de> <20140825174610.GA13737@obsidianresearch.com> <53FB9AC4.8010704@gmail.com> <660fe929-1f16-4e22-8bd3-0388cd363978@BY2FFO11FD038.protection.gbl> <540099AF.4020005@suse.de> <20140829173102.GA30917@obsidianresearch.com> In-Reply-To: <20140829173102.GA30917@obsidianresearch.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/29/2014 10:31 AM, Jason Gunthorpe wrote: > On Fri, Aug 29, 2014 at 08:35:36AM -0700, Sören Brinkmann wrote: > >> The compatible string is listed as optional property for PHYs. So, not >> having one is an option, I guess. But, I'd also prefer to at least keep >> the -c22 one, since I saw problems when I tried using -c45 (the Zed phy >> should support it...). > > -c45 and -c22 use a completely different MDIO protocol, Zed doesn't > have a 10GE port, so it certainly doesn't use -c45. Most recent 1GbE PHYs should also implement clause 45. It is a nice improvement if you are using lot of transactions, otherwise clause 45 over clause 22 is suitable and supported by the PHY library (for EEE in particular). > > If there is no compatible string at all the defined default is to use > -c22. Absolutely, the current binding makes that property optional, but I think we should make it mandatory instead. > >> Also, so far, we haven't had any phy nodes in our Zynq dts files and >> Ethernet worked, so the auto-detection there works pretty well >> apparently. But it may be problematic if more than a single PHY is on >> the MDIO bus, I'd assume. > > Phy autodetection has always worked in some cases, but for DT ethernet > bindings it is expected that there is an option to specify an explicit > MDIO bus, and a phy-handle phandle to point to the phy. The phy should > be explicitly called out with the fixed MDIO address specified to > avoid sketchy MDIO address auto probing. > > This provides the framework to specify interrupts and register > overrides for the phy in the DT. Absolutely, on the plus side, avoiding auto-detection also allows you to have a shorter boot time (usually by a factor of few hundreds of msecs depending on how the MDIO buses handle errors). -- Florian From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Fainelli Subject: Re: [PATCH 3/3] ARM: zynq: DT: Add Ethernet phys Date: Fri, 29 Aug 2014 11:23:57 -0700 Message-ID: <5400C53D.70501@gmail.com> References: <1408550219-19825-3-git-send-email-soren.brinkmann@xilinx.com> <5a7b6f57-b6c0-4fb3-af0d-d403277c0207@BN1AFFO11FD045.protection.gbl> <53F5D8D9.7040604@suse.de> <20140825174610.GA13737@obsidianresearch.com> <53FB9AC4.8010704@gmail.com> <660fe929-1f16-4e22-8bd3-0388cd363978@BY2FFO11FD038.protection.gbl> <540099AF.4020005@suse.de> <20140829173102.GA30917@obsidianresearch.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20140829173102.GA30917-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jason Gunthorpe , =?UTF-8?B?U8O2cmVu?= =?UTF-8?B?IEJyaW5rbWFubg==?= Cc: =?UTF-8?B?QW5kcmVhcyBGw6RyYmVy?= , Mark Rutland , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Russell King , Pawel Moll , Ian Campbell , Michal Simek , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Rob Herring , Kumar Gala , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" List-Id: devicetree@vger.kernel.org On 08/29/2014 10:31 AM, Jason Gunthorpe wrote: > On Fri, Aug 29, 2014 at 08:35:36AM -0700, S=C3=B6ren Brinkmann wrote: >=20 >> The compatible string is listed as optional property for PHYs. So, n= ot >> having one is an option, I guess. But, I'd also prefer to at least k= eep >> the -c22 one, since I saw problems when I tried using -c45 (the Zed = phy >> should support it...). >=20 > -c45 and -c22 use a completely different MDIO protocol, Zed doesn't > have a 10GE port, so it certainly doesn't use -c45. Most recent 1GbE PHYs should also implement clause 45. It is a nice improvement if you are using lot of transactions, otherwise clause 45 over clause 22 is suitable and supported by the PHY library (for EEE in particular). >=20 > If there is no compatible string at all the defined default is to use > -c22. Absolutely, the current binding makes that property optional, but I think we should make it mandatory instead. >=20 >> Also, so far, we haven't had any phy nodes in our Zynq dts files and >> Ethernet worked, so the auto-detection there works pretty well >> apparently. But it may be problematic if more than a single PHY is o= n >> the MDIO bus, I'd assume. >=20 > Phy autodetection has always worked in some cases, but for DT etherne= t > bindings it is expected that there is an option to specify an explici= t > MDIO bus, and a phy-handle phandle to point to the phy. The phy shoul= d > be explicitly called out with the fixed MDIO address specified to > avoid sketchy MDIO address auto probing. >=20 > This provides the framework to specify interrupts and register > overrides for the phy in the DT. Absolutely, on the plus side, avoiding auto-detection also allows you t= o have a shorter boot time (usually by a factor of few hundreds of msecs depending on how the MDIO buses handle errors). -- =46lorian -- To unsubscribe from this list: send the line "unsubscribe devicetree" i= n the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 From: f.fainelli@gmail.com (Florian Fainelli) Date: Fri, 29 Aug 2014 11:23:57 -0700 Subject: [PATCH 3/3] ARM: zynq: DT: Add Ethernet phys In-Reply-To: <20140829173102.GA30917@obsidianresearch.com> References: <1408550219-19825-3-git-send-email-soren.brinkmann@xilinx.com> <5a7b6f57-b6c0-4fb3-af0d-d403277c0207@BN1AFFO11FD045.protection.gbl> <53F5D8D9.7040604@suse.de> <20140825174610.GA13737@obsidianresearch.com> <53FB9AC4.8010704@gmail.com> <660fe929-1f16-4e22-8bd3-0388cd363978@BY2FFO11FD038.protection.gbl> <540099AF.4020005@suse.de> <20140829173102.GA30917@obsidianresearch.com> Message-ID: <5400C53D.70501@gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 08/29/2014 10:31 AM, Jason Gunthorpe wrote: > On Fri, Aug 29, 2014 at 08:35:36AM -0700, S?ren Brinkmann wrote: > >> The compatible string is listed as optional property for PHYs. So, not >> having one is an option, I guess. But, I'd also prefer to at least keep >> the -c22 one, since I saw problems when I tried using -c45 (the Zed phy >> should support it...). > > -c45 and -c22 use a completely different MDIO protocol, Zed doesn't > have a 10GE port, so it certainly doesn't use -c45. Most recent 1GbE PHYs should also implement clause 45. It is a nice improvement if you are using lot of transactions, otherwise clause 45 over clause 22 is suitable and supported by the PHY library (for EEE in particular). > > If there is no compatible string at all the defined default is to use > -c22. Absolutely, the current binding makes that property optional, but I think we should make it mandatory instead. > >> Also, so far, we haven't had any phy nodes in our Zynq dts files and >> Ethernet worked, so the auto-detection there works pretty well >> apparently. But it may be problematic if more than a single PHY is on >> the MDIO bus, I'd assume. > > Phy autodetection has always worked in some cases, but for DT ethernet > bindings it is expected that there is an option to specify an explicit > MDIO bus, and a phy-handle phandle to point to the phy. The phy should > be explicitly called out with the fixed MDIO address specified to > avoid sketchy MDIO address auto probing. > > This provides the framework to specify interrupts and register > overrides for the phy in the DT. Absolutely, on the plus side, avoiding auto-detection also allows you to have a shorter boot time (usually by a factor of few hundreds of msecs depending on how the MDIO buses handle errors). -- Florian