From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail1.windriver.com (mail1.windriver.com [147.11.146.13]) by yocto-www.yoctoproject.org (Postfix) with ESMTP id E6333E0027F for ; Fri, 24 Aug 2012 09:55:59 -0700 (PDT) Received: from ALA-HCA.corp.ad.wrs.com (ala-hca [147.11.189.40]) by mail1.windriver.com (8.14.5/8.14.3) with ESMTP id q7OGtw1Q006661 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=FAIL) for ; Fri, 24 Aug 2012 09:55:58 -0700 (PDT) Received: from msp-dhcp13.wrs.com (172.25.34.13) by ALA-HCA.corp.ad.wrs.com (147.11.189.50) with Microsoft SMTP Server id 14.2.309.2; Fri, 24 Aug 2012 09:55:59 -0700 Message-ID: <5037B21E.4060004@windriver.com> Date: Fri, 24 Aug 2012 11:55:58 -0500 From: Mark Hatle Organization: Wind River Systems User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:14.0) Gecko/20120713 Thunderbird/14.0 MIME-Version: 1.0 To: References: In-Reply-To: Subject: Re: TARGET_FPU not getting populated for powerpc 405/440 fpu-hard targets X-BeenThere: yocto@yoctoproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Discussion of all things Yocto List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 24 Aug 2012 16:56:00 -0000 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit On 8/24/12 11:49 AM, Elvis Dowson wrote: > Hi Khem, > > On Aug 24, 2012, at 8:35 PM, Khem Raj wrote: > >> On Fri, Aug 24, 2012 at 9:27 AM, Elvis Dowson > > wrote: >>> I just observed that TARGET_FPU is not getting populated, when you do >>> a build for fpu-hard targets. For fpu-soft targets, it displays TARGET_FPU = >>> "soft", but for fpu-hard targets, it display TARGET_FPU = "". >> >> that means default is hard for this architecture. This option is >> essentially used to configure gcc >> unless your fpu is special like fsl one's you are good here. > > The FPU unit is an IP core, that is attached to a generic PowerPC405 or > PowerPC440 embedded processor core on the FPGA, which by default doesn't contain > an FPU unit. > > In the Xilinx FPGA hardware project, I have to add this FPU unit, and there are > some additional options that I can see relevant to this setup with the FPU unit, > such as -mxilinx-fpu and -mfpu=dp_full > > Should I specify them in TUNE_CCARGS (as shown below) > or TUNE_FEATURES_tune-ppc405e (not done below) or specify the same values for > both variables ? > > TUNE_CCARGS += "${@bb.utils.contains("TUNE_FEATURES", "ppc405e", "-mcpu=405fp > -mxilinx-fpu -mfpu=dp_full", "", d)}" > > AVAILTUNES += "ppc405e" > TUNE_FEATURES_tune-ppc405e = "m32 ppc405e fpu-hard" fpu-hard is the classic PowerPC FPU unit. If that is what these ip blocks implement then there is nothing further required. If the unit does NOT include a classic PowerPC FPU, then you should not be using fpu-hard. If it -also- implements additional FPU instructions via the -m...fpu stuff specific to the IP blocks, then that is where the target_fpu comes in and some other changes will be necessary.... It's been a while since I worked through this, but the e500 stuff may be a reasonable example of how to implement it. --Mark > Best regards, > > Elvis Dowson > > > _______________________________________________ > yocto mailing list > yocto@yoctoproject.org > https://lists.yoctoproject.org/listinfo/yocto >