From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.windriver.com ([147.11.1.11]) by linuxtogo.org with esmtp (Exim 4.72) (envelope-from ) id 1Qm5BP-0007l9-1S for openembedded-core@lists.openembedded.org; Wed, 27 Jul 2011 16:33:59 +0200 Received: from ALA-HCA.corp.ad.wrs.com (ala-hca [147.11.189.40]) by mail.windriver.com (8.14.3/8.14.3) with ESMTP id p6RER6NL016215 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=FAIL) for ; Wed, 27 Jul 2011 07:29:43 -0700 (PDT) Received: from Macintosh-5.local (172.25.36.226) by ALA-HCA.corp.ad.wrs.com (147.11.189.50) with Microsoft SMTP Server id 14.1.255.0; Wed, 27 Jul 2011 07:27:30 -0700 Message-ID: <4E302051.1010308@windriver.com> Date: Wed, 27 Jul 2011 09:27:29 -0500 From: Mark Hatle Organization: Wind River Systems User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:5.0) Gecko/20110624 Thunderbird/5.0 MIME-Version: 1.0 To: References: <346abefc87d21d0cc111ef87a6e48f40c5b6cb0b.1311683981.git.richard.purdie@linuxfoundation.org> <1311769062.30326.322.camel@phil-desktop> <1311773637.2344.365.camel@rex> In-Reply-To: <1311773637.2344.365.camel@rex> 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 14:33:59 -0000 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit On 7/27/11 8:33 AM, Richard Purdie wrote: > 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 .= "${@bb.utils.contains("TUNE_FEATURES", [ "armv7", "thumb" ], "t2", "", d)}" >> >> This is wrong: ARMv6 doesn't imply Thumb-2. > > Ah, yes. I'll fix this. Are you sure? I thought ARMv6 -was- the first to support Thumb-2. And armv5/4 were thumb(1). Note, not all ARMv6 processors contain thumb support. >>> +# Whether to compile with code to allow interworking between the two >>> +# instruction sets. This allows thumb code to be executed on a primarily >>> +# arm system and vice versa. It is strongly recommended that DISTROs not >>> +# turn this off - the actual cost is very small. >>> +TUNEVALID[no-thumb-interwork] = "Disable mixing of thumb and ARM functions" >>> +TUNE_CCARGS += "${@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. In the original work I did it was just tune-xscale (no be). AFAIK there is no little endian version of xscale. (there was an iwmmxt that was similar to xscale, but was slightly different.) >> 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 > > > > _______________________________________________ > Openembedded-core mailing list > Openembedded-core@lists.openembedded.org > http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/openembedded-core