From mboxrd@z Thu Jan 1 00:00:00 1970 From: robherring2@gmail.com (Rob Herring) Date: Thu, 01 Aug 2013 08:48:19 -0500 Subject: [Ksummit-2013-discuss] DT bindings as ABI [was: Do we have people interested in device tree janitoring / cleanup?] In-Reply-To: <1375352315.22084.138.camel@shinybook.infradead.org> References: <20130725175702.GC22291@e106331-lin.cambridge.arm.com> <1999586.84BnWE5EUh@thinkpad> <20130731191209.GA8027@netboy> <1409617.9untvfnOTJ@flatron> <20130731200017.GC8027@netboy> <20130731201457.GA24642@n2100.arm.linux.org.uk> <20130731204817.GC24642@n2100.arm.linux.org.uk> <1375352315.22084.138.camel@shinybook.infradead.org> Message-ID: <51FA6723.9010608@gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 08/01/2013 05:18 AM, David Woodhouse wrote: > On Wed, 2013-07-31 at 17:26 -0400, jonsmirl at gmail.com wrote: >> Alternatively you may be of the belief that it is impossible to get >> rid of the board specific code. But x86 doesn't have any of it, why >> should ARM? > > The reason x86 doesn't have it is because it carries three decades worth > of legacy baggage so that it can still look like a 1980s IBM PC when > necessary. > > There *have* been some x86 platforms which abandon that legacy crap, and > for those we *do* have board-specific code. (Is James still maintaining > Voyager support? It feels very strange to talk about Voyager with it > *not* being the 'legacy crap' in question...) > > We've even seen *recent* attempts to abandon the legacy crap in the > embedded x86 space, which backtracked and added it all back again ? in > part because x86 lacked any sane way to describe the hardware if it > wasn't pretending to be a PC. ACPI doesn't cut it, and DT "wasn't > invented here"... > > Unless you want the ARM world to settle on a strategy of "all the world > is an Assabet", I'd be careful what you wish for... There is some level of belief that ACPI will enable running this years OS on next years h/w. This idea is completely flawed as long as ARM vendors don't design for compatibility, spin the Si for compatibility issues, and have some mechanism to emulate legacy h/w. All the discussions and issues around DT bindings and processes will apply to ACPI bindings as well. Rob