From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from az33egw02.freescale.net (az33egw02.freescale.net [192.88.158.103]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "az33egw02.freescale.net", Issuer "Thawte Premium Server CA" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id AD2FEDE112 for ; Thu, 23 Apr 2009 07:47:17 +1000 (EST) Message-ID: <49EF9019.7000102@freescale.com> Date: Wed, 22 Apr 2009 16:46:01 -0500 From: Timur Tabi MIME-Version: 1.0 To: Kumar Gala Subject: Re: removing get_immrbase()?? References: <49EF7B11.2000006@freescale.com> <49EF7B1C.2080105@freescale.com> <282847E1-AE1A-44EF-9D18-AF2884105FA5@kernel.crashing.org> <49EF8D42.7010104@freescale.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Cc: Scott Wood , Linuxppc-dev Development List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Kumar Gala wrote: > The specific issue I'm talking about is the addition of new nodes that > might break old device trees. New nodes or new properties? The CPM nodes are not new. On some device trees, the original versions did not have a compatible property for the CPM nodes (e.g. commit 0b5cf10691eb2c95a9126bf25f5e084d83d5d743). Therefore, there are device trees out there that are missing some property. Like I said earlier, if you can demonstrate that *all* of these device tree would be broken with the latest kernel anyway, then we don't need to worry about backwards compatibility. I'm tired of debugging customer issues where the kernel is updated but the firmware and device tree aren't. IMHO, Kernel developers are generally too lax when it comes to firmware and device tree backwards compatibility, and I think that's wrong. -- Timur Tabi Linux kernel developer at Freescale