From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-in-13.arcor-online.net (mail-in-13.arcor-online.net [151.189.21.53]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mx.arcor.de", Issuer "Thawte Premium Server CA" (verified OK)) by ozlabs.org (Postfix) with ESMTP id 1D7A6DDEC9 for ; Tue, 17 Apr 2007 20:26:06 +1000 (EST) In-Reply-To: <20070416193110.77b63e4b.kim.phillips@freescale.com> References: <20070413012542.343eb848.kim.phillips@freescale.com> <95a9680c565aa196a4ef78964ef9dee1@kernel.crashing.org> <20070416102533.0f87396f.kim.phillips@freescale.com> <20070416115729.292c10b1.kim.phillips@freescale.com> <53810df560c7af272cd1c71c9d5fa1ab@kernel.crashing.org> <20070416193110.77b63e4b.kim.phillips@freescale.com> Mime-Version: 1.0 (Apple Message framework v623) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: <788e650fbb3f95eaf1bfb6955f9cef17@kernel.crashing.org> From: Segher Boessenkool Subject: Re: [PATCH 1/4 v2] powerpc: document max-speed and interface-type properties Date: Tue, 17 Apr 2007 12:25:51 +0200 To: Kim Phillips Cc: linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , >> You can put "rgmii" or whatever in the "compatible" property >> as well. >> > I don't understand how intermixing PHY device compatibility with the > UCC connection to the PHY would be a good thing. "compatible" means "what kind of device is this", for the purposes of a client program (i.e., Linux) matching a driver to it (i.e., it should say what kind of PHY it is, and phylib should use that info -- in most cases, it won't need more than the least specific entry in "compatible", i.e. "rgmii" or whatever. >>> If I were to put the properties in the PHY node, I wouldn't be able >>> to >>> describe a 1000Mbit/s capable UCC connected to a 100Mbit/s capable >>> PHY, >>> or vice versa. >> >> Of course you can. The "compatible" in the enet node >> implies it can do 1000Mbps; the "compatible" in the >> PHY node implies it does 100Mbps. > > compatible in the UCC node is currently set to "ucc_geth", which does > not necessarily imply that that UCC can do 1000Mbit/s. Some UCCs can > only do 100Mbit/s. So those UCCs should have a different "compatible" entry. It's not rocket science. > We currently do not have hardware that connects UCC with max-speed x > with a PHY with max. speed capability of y, where x != y, so there is > currently no need to specify the speed of the PHY. Not that that would > be needed; the phylib would call ucc_geth's adjust_link with the new > speed. Note that the max-speed property is used to set registers in > the > UCC only. max-speed of connection = min(max-speed of enet, max-speed of PHY) -- and both of those are implied by their respective "compatible" properties. Segher