Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751770AbbLKSqI (ORCPT ); Fri, 11 Dec 2015 13:46:08 -0500 Received: from pmta2.delivery5.ore.mailhop.org ([54.186.218.12]:20292 "EHLO pmta2.delivery5.ore.mailhop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751271AbbLKSqG (ORCPT ); Fri, 11 Dec 2015 13:46:06 -0500 X-DKIM: OpenDKIM Filter v2.6.8 io 371C080013 Date: Fri, 11 Dec 2015 18:46:02 +0000 From: Jason Cooper To: Josh Triplett Cc: Arnd Bergmann , Detlef Vollmann , linux-arm-kernel@lists.infradead.org, Andrew Lunn , Russell King , Benjamin Cama , linux-kernel@vger.kernel.org, Gregory CLEMENT , "Evgeniy A. Dushistov" , Sebastian Hesselbarth Subject: Re: [PATCH 0/5] ARM: orion5x/dove/mv78xx0 multiplatform Message-ID: <20151211184602.GE18249@io.lakedaemon.net> References: <1448466557-435335-1-git-send-email-arnd@arndb.de> <2992463.fVOGazvIkH@wuerfel> <5669F5F8.5010005@vollmann.ch> <14967875.ttNXUbSTvS@wuerfel> <20151211133601.GB18249@io.lakedaemon.net> <20151211182730.GA15800@cloud> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151211182730.GA15800@cloud> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2506 Lines: 59 On Fri, Dec 11, 2015 at 10:27:30AM -0800, Josh Triplett wrote: > On Fri, Dec 11, 2015 at 01:36:01PM +0000, Jason Cooper wrote: > > +Josh > > > > Hey Arnd, Detlef, > > > > On Fri, Dec 11, 2015 at 12:10:55AM +0100, Arnd Bergmann wrote: > > > On Thursday 10 December 2015 23:00:24 Detlef Vollmann wrote: > > > > On 12/10/15 22:29, Arnd Bergmann wrote: > > > > > On Thursday 10 December 2015 22:14:25 Detlef Vollmann wrote: > > > > >> On 12/10/15 21:59, Arnd Bergmann wrote: > > > > > It may also be worth investigating what has made CONFIG_OF so costly, > > > > Probably because too much is done at runtime and too few things can > > > > be fixed at build time. > > > > > > > > > maybe we can reduce this a bit again. > > > > Probably not without turning the wheel backward :-( > > > > > > > > So for the test: yes it works, but I'm unhappy with it. > > > > > > I'm not too happy about adding 80kb to the uncompressed kernel > > > image either. I've spent some more time now trying to find where > > > we added the bloat. It's mainly in drivers, not in arch specific > > > code, a kilobyte here and there eventually adds up, but the largest > > > portion with a little over 50% of the total diff is drivers/of. > > > > Wasn't there an idea kicked around a while ago to create a > > dt2boardfile script/executable*? Then, during kernel configuration, you > > enable it and select which dts file you want. It would disable > > CONFIG_OF, multiplatform, etc. And generate a board_file.c from the dts > > file. > > > > If anything, it might be worth asking the kernel tinification [1], [2] > > folks if they'd be interested in taking this on... > > No objection if you want to add it to the task list on > tiny.wiki.kernel.org (on the more difficult end). Done. > I don't know if you could generate a board file, but I do wonder if you > could effectively compile in a parsed description and ditch the parser. > Bonus if you can make the values parsed out of it into compile-time > constants for constant folding. After a bit of discussion with Arnd on irc, I agree. Going to a board file doesn't really work since the logic is now mostly in the drivers probe functions. The dts parsing -> compile-time constants is worth looking into. thx, Jason. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/