From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by yocto-www.yoctoproject.org (Postfix, from userid 118) id 30A0DE00957; Wed, 15 Apr 2015 08:22:58 -0700 (PDT) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on yocto-www.yoctoproject.org X-Spam-Level: X-Spam-Status: No, score=-2.7 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, RCVD_IN_DNSWL_LOW autolearn=ham version=3.3.1 X-Spam-HAM-Report: * 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider * (picmaster[at]mail.bg) * -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low * trust * [193.201.172.118 listed in list.dnswl.org] * -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% * [score: 0.0000] * -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's * domain * 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily * valid * -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature Received: from mx2.mail.bg (mx2.mail.bg [193.201.172.118]) by yocto-www.yoctoproject.org (Postfix) with ESMTP id 0431BE0092E for ; Wed, 15 Apr 2015 08:22:54 -0700 (PDT) Received: from [192.168.0.62] (unknown [93.152.143.60]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mx2.mail.bg (Postfix) with ESMTPSA id A1D106001DFE; Wed, 15 Apr 2015 18:22:52 +0300 (EEST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=mail.bg; s=default; t=1429111372; bh=02AIo3/CKhSkfU6N5AsPgVcByJ1VvBeqOrVUqkcQBYU=; h=Message-ID:Date:From:MIME-Version:To:CC:Subject:References: In-Reply-To:Content-Type:Content-Transfer-Encoding; b=1iGaA/DMUnm6ytK7Ib50ABBC6TmbgFOtBEZBd+jBaxcyBv17huv+KlzgQd/uu34lR aKXseZynDSbT84ISSWxca4VOddQ0yCAusrrr/n8qwkxsc0cAZ4G4dAMVxwRM2lIheS N9jRAZKE7e95nJI5R6O0GWVCXUDuCguRqTiOAMeU= Message-ID: <552E824C.5080603@mail.bg> Date: Wed, 15 Apr 2015 18:22:52 +0300 From: Nikolay Dimitrov User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Icedove/31.6.0 MIME-Version: 1.0 To: Bruce Ashfield References: <355BE46A91031048906B695426A8D8E616B7BE37@DEFTHW99EH4MSX.ww902.siemens.net> <552E63F1.9090406@windriver.com> In-Reply-To: <552E63F1.9090406@windriver.com> Cc: "yocto@yoctoproject.org" , Patches and discussions about the oe-core layer Subject: Re: Move device tree generation from include file to bbclass X-BeenThere: yocto@yoctoproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Discussion of all things Yocto Project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 15 Apr 2015 15:22:58 -0000 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Hi Bruce, On 04/15/2015 04:13 PM, Bruce Ashfield wrote: > On 2015-04-15 08:33 AM, Bach, Pascal wrote: >> Hi >> > > Adding oe-core, since that's the right place to have a discussion > like this. > >> As ARM now also moved to device tree it look like in future we will >> have more kernels that are using device tree then ones that are >> not. > > True, but it has been like this for quite some time now :) > >> As far as I understand currently the generation of device trees is >> controlled via KERNEL_DEVICETREE and is handled in via an include >> file recipes-kernel/linux/linux-dtb.inc. >> >> I was thinking about moving this include into a class so it becomes >> easier to use. Before I dive into implementing something I would >> like some feedback from the community. > > The big trick with changing anything like this is compatibility with > existing recipes. Whatever we do, existing recipes and layers > shouldn't be broken .. or if they are broken, there should be a > compelling technical reason to do so. > >> >> I have the following variant in mind. >> >> Add the device tree generation to the current kernel.bbclass (or >> let kernel.bblcass inherit from a kernel-dtb.bbclass). This way all >> kernels would automatically be DT enabled. The class would check if >> KERNEL_DEVICETREE is set and generate device trees based on this >> information. For boards that don't have KERNEL_DEVICETREE set the >> class would do nothing and the behavior is like before. The >> advantage I see with this approach is that the only thing a user >> needs to do is to set KERNEL_DEVICETREE in the board and make sure >> the device trees are available in the kernel they like to build. > > That's pretty much the experience that most users have now, since > there's nearly always a kernel recipe created, that recipe includes > linux-dtb.inc, and sets KERNEL_DEVICETREE. As far as I understood, Pascal's idea is to remove the need for user recipes to include linux-dtb.inc, and provide this functionality via inheritance. > Everything else happens to build and package the device tree. > > Was there something specifically that was causing issues with the > current way of building them ? > > Cheers, > > Bruce > >> >> I appreciate your feedback? >> >> Regards Pascal >> > Regards, Nikolay