From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 3C85ADDFCD for ; Thu, 23 Apr 2009 07:57:48 +1000 (EST) Message-Id: <5D0145E3-0A98-429E-8D53-1A8DF4216462@kernel.crashing.org> From: Kumar Gala To: Scott Wood In-Reply-To: <49EF8E3A.4060304@freescale.com> Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Mime-Version: 1.0 (Apple Message framework v930.3) Subject: Re: removing get_immrbase()?? Date: Wed, 22 Apr 2009 16:55:42 -0500 References: <49EF7B11.2000006@freescale.com> <49EF7B1C.2080105@freescale.com> <282847E1-AE1A-44EF-9D18-AF2884105FA5@kernel.crashing.org> <49EF8E3A.4060304@freescale.com> Cc: Linuxppc-dev Development , Timur Tabi List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Apr 22, 2009, at 4:38 PM, Scott Wood wrote: > Kumar Gala wrote: >> I disagree. If you update your kernel you should update your >> device tree (thus we have .dts in the kernel tree and not somewhere >> else). > > No. The device tree is a means to pass information from the > firmware to the kernel. It is part of the firmware. That the > repository of trees is in the Linux kernel for any boards which are > not including the tree inside a bootwrapper is a historical accident. I think its a point of view argument. I don't agree its part of the firmware, at least not part of the firmware we use (u-boot). > Updating the dtb with the kernel just shifts the risk of > incompatibility to interactions between the firmware and the dtb. > The same backwards compatibility considerations when making kernel > changes that depend on firmware changes should be made when making > kernel changes that depend on dts changes. As I told Timur, I'm speaking of addition of new nodes and code that parses and expect those nodes to be there. - k