From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from 93-97-173-237.zone5.bethere.co.uk ([93.97.173.237] helo=tim.rpsys.net) by linuxtogo.org with esmtp (Exim 4.72) (envelope-from ) id 1Qm4Jh-00029U-Py for openembedded-core@lists.openembedded.org; Wed, 27 Jul 2011 15:38:30 +0200 Received: from localhost (localhost [127.0.0.1]) by tim.rpsys.net (8.13.6/8.13.8) with ESMTP id p6RDYF25030117 for ; Wed, 27 Jul 2011 14:34:15 +0100 Received: from tim.rpsys.net ([127.0.0.1]) by localhost (tim.rpsys.net [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 29338-05 for ; Wed, 27 Jul 2011 14:34:11 +0100 (BST) Received: from [192.168.3.10] ([192.168.3.10]) (authenticated bits=0) by tim.rpsys.net (8.13.6/8.13.8) with ESMTP id p6RDY7VP030111 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Wed, 27 Jul 2011 14:34:08 +0100 From: Richard Purdie To: Patches and discussions about the oe-core layer In-Reply-To: <1311769062.30326.322.camel@phil-desktop> References: <346abefc87d21d0cc111ef87a6e48f40c5b6cb0b.1311683981.git.richard.purdie@linuxfoundation.org> <1311769062.30326.322.camel@phil-desktop> Date: Wed, 27 Jul 2011 14:33:57 +0100 Message-ID: <1311773637.2344.365.camel@rex> Mime-Version: 1.0 X-Mailer: Evolution 2.32.2 X-Virus-Scanned: amavisd-new at rpsys.net Subject: Re: [PATCH 1/3] Add ARM tune file overhaul based largely on work from Mark Hatle X-BeenThere: openembedded-core@lists.openembedded.org X-Mailman-Version: 2.1.11 Precedence: list Reply-To: Patches and discussions about the oe-core layer List-Id: Patches and discussions about the oe-core layer List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 27 Jul 2011 13:38:30 -0000 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit On Wed, 2011-07-27 at 13:17 +0100, Phil Blundell wrote: > On Tue, 2011-07-26 at 13:44 +0100, Richard Purdie wrote: > > +TARGET_FPU = "${@d.getVar('ARMPKGSFX_FPU', True).strip('-') or 'soft'}" > > This seems a bit backwards. Shouldn't TARGET_FPU be the primary > variable and then the package suffix be computed from that, rather than > vice versa? It's been "fun" to use the rather limited constructs we have in these variables to construct the end result. I suspect this way around, it was the easiest way to get the right variables in the right places. > > +ARMPKGSFX_THUMB .= "${@bb.utils.contains("TUNE_FEATURES", [ "armv4", "thumb" ], "t", "", d)}" > > +ARMPKGSFX_THUMB .= "${@bb.utils.contains("TUNE_FEATURES", [ "armv5", "thumb" ], "t", "", d)}" > > +ARMPKGSFX_THUMB .= "${@bb.utils.contains("TUNE_FEATURES", [ "armv6", "thumb" ], "t2", "", d)}" > > +ARMPKGSFX_THUMB .= "${@bb.utils.contains("TUNE_FEATURES", [ "armv7", "thumb" ], "t2", "", d)}" > > This is wrong: ARMv6 doesn't imply Thumb-2. Ah, yes. I'll fix this. > > +# Whether to compile with code to allow interworking between the two > > +# instruction sets. This allows thumb code to be executed on a primarily > > +# arm system and vice versa. It is strongly recommended that DISTROs not > > +# turn this off - the actual cost is very small. > > +TUNEVALID[no-thumb-interwork] = "Disable mixing of thumb and ARM functions" > > +TUNE_CCARGS += "${@bb.utils.contains("TUNE_FEATURES", "no-thumb-interwork", "-mno-thumb-interwork", "-mthumb-interwork", d)}" > > +OVERRIDES .= "${@bb.utils.contains("TUNE_FEATURES", "no-thumb-interwork", ":thumb-interwork", "", d)}" > > This is only relevant for v4t, I guess. Interworking is basically > always on for v5 and later and (CeSI aside) it's impossible on v4, so > hardly anybody is going to be flipping this switch. I'm not sure it > really merits an OVERRIDE. I'd be happy to remove this option if there are no objections. It was left for compatibility with the existing tune-thumb file but as you say, it likely doesn't make much sense. > > --- a/meta/conf/machine/include/tune-xscale.inc > > +++ b/meta/conf/machine/include/tune-xscale.inc > > @@ -1,11 +1,17 @@ > > -require conf/machine/include/arm/arch-arm.inc > > +DEFAULTTUNE ?= "xscale" > > > > -INHERIT += "siteinfo" > > +require conf/machine/include/arm/arch-armv5-dsp.inc > > > > -TUNE_CCARGS = "-march=armv5te -mtune=xscale" > > -TARGET_CC_KERNEL_ARCH = "-march=armv5te -mtune=xscale" > > -TUNE_PKGARCH = "${@['armv5teb', 'armv5te'][bb.data.getVar('SITEINFO_ENDIANESS', d, 1) == 'le']}" > > -PACKAGE_EXTRA_ARCHS = "${@['armeb armv4b armv4tb armv5teb', 'arm armv4 armv4t armv5te'][bb.data.getVar('SITEINFO_ENDIANESS', d, 1) == 'le']}" > > +TUNEVALID[xscale] = "Enable PXA255/PXA26x Xscale specific processor optimizations" > > +TUNE_CCARGS += "${@bb.utils.contains("TUNE_FEATURES", "xscale", "-mtune=xscale", "", d)}" > > + > > +AVAILTUNES += "xscale" > > +TUNE_FEATURES_tune-xscale = "${TUNE_FEATURES_tune-armv5te} xscale" > > +PACKAGE_EXTRA_ARCHS_tune-xscale = "${PACKAGE_EXTRA_ARCHS_tune-armv5te}" > > + > > +AVAILTUNES += "xscale-be" > > +TUNE_FEATURES_tune-xscale = "${TUNE_FEATURES_tune-armv5teb} xscale" > > +PACKAGE_EXTRA_ARCHS_tune-xscale = "${PACKAGE_EXTRA_ARCHS_tune-armv5teb}" > > I guess that should be "_tune-xscale-be". Yes, I'll fix, well spotted. > All in all it seems as though there's an awful lot of expanded cross > products in this set of patches and I can't help wondering whether a lot > of this stuff would be better computed programmatically. I wouldn't be > at all surprised if there are other copy-and-paste errors like the > xscale one lurking in that mass of overrides, but it's very hard to spot > them by eye. It seems particularly unfortunate that everything has to > be written out twice, once for big-endian and once for little-endian, > given that endianness is almost entirely orthogonal to all the other > "tuning" parameters. At least three of us have now done a pass over this so hopefully we've spotted the major ones but I agree its less than ideal. The alternative is to post process the variables somehow, or turn it all into anonymous python (which from a .conf file is not as easy as it sounds). I do like the fact that it allows some standardisation of the options available in a given tune file as whether or not big endian was even possible was previously hit and miss. So I think its an improvement but likely not the finished end result. Cheers, Richard