From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by yocto-www.yoctoproject.org (Postfix, from userid 118) id 13E90E00957; Wed, 15 Apr 2015 08:26:41 -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 * (bruce.ashfield[at]gmail.com) * -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low * trust * [209.85.214.174 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 mail-ob0-f174.google.com (mail-ob0-f174.google.com [209.85.214.174]) by yocto-www.yoctoproject.org (Postfix) with ESMTP id BC2FDE0092E for ; Wed, 15 Apr 2015 08:26:39 -0700 (PDT) Received: by obbeb7 with SMTP id eb7so24623233obb.3 for ; Wed, 15 Apr 2015 08:26:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=mfR9MTokT/fIcsJDiP5YoRhQqZ4X0q4XV9+eLcjNQ88=; b=BuQRjtIY+rXUvgKdxCzwadkoosYrExt/vz48iNz8EQtgWGVdmJZ2l0MmfleWoZ7oFB ht8c2oZPWlhDL3YPOYQfzZjv8sjHyHx7Qup6oGsSakQJpZBPNnWFpyMxP2hcN/UvmtRK 6c7CS+q4NMMETJVSqD3mHkm3Li3YDXWvYWg3AQTH17CFGsujVaGFEq+UrZXBFFRUob71 eRBHP45aC7DVRAmOKC2UHq7F9PpTMn6KJFUkYcBxku+9jaDX6VcAHw91zLK3E/ALo0Dd N0ROUPbwPN/BLtCj5yFLrnKZm4qO8Lhgb2za4cKJ7cfr5dzxRWWU5AgzAq4mL7atauti 9ijQ== MIME-Version: 1.0 X-Received: by 10.42.111.68 with SMTP id t4mr31692309icp.36.1429111565152; Wed, 15 Apr 2015 08:26:05 -0700 (PDT) Received: by 10.107.158.20 with HTTP; Wed, 15 Apr 2015 08:26:05 -0700 (PDT) In-Reply-To: <552E824C.5080603@mail.bg> References: <355BE46A91031048906B695426A8D8E616B7BE37@DEFTHW99EH4MSX.ww902.siemens.net> <552E63F1.9090406@windriver.com> <552E824C.5080603@mail.bg> Date: Wed, 15 Apr 2015 11:26:05 -0400 Message-ID: From: Bruce Ashfield To: Nikolay Dimitrov 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 15:26:41 -0000 Content-Type: text/plain; charset=UTF-8 On Wed, Apr 15, 2015 at 11:22 AM, Nikolay Dimitrov wrote: > 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. That is obvious. My questions are around "why". There's no big technical advantage, and if you remove that existing file, you break existing recipes. Which means you need to leave a stub in place. So without a technical advantage, it's churn for the sake of churn. Bruce > >> 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 > > -- > _______________________________________________ > yocto mailing list > yocto@yoctoproject.org > https://lists.yoctoproject.org/listinfo/yocto -- "Thou shalt not follow the NULL pointer, for chaos and madness await thee at its end" From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ob0-f172.google.com (mail-ob0-f172.google.com [209.85.214.172]) by mail.openembedded.org (Postfix) with ESMTP id BF74D6AC24 for ; Wed, 15 Apr 2015 15:26:44 +0000 (UTC) Received: by obbfy7 with SMTP id fy7so23903339obb.2 for ; Wed, 15 Apr 2015 08:26:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=mfR9MTokT/fIcsJDiP5YoRhQqZ4X0q4XV9+eLcjNQ88=; b=BuQRjtIY+rXUvgKdxCzwadkoosYrExt/vz48iNz8EQtgWGVdmJZ2l0MmfleWoZ7oFB ht8c2oZPWlhDL3YPOYQfzZjv8sjHyHx7Qup6oGsSakQJpZBPNnWFpyMxP2hcN/UvmtRK 6c7CS+q4NMMETJVSqD3mHkm3Li3YDXWvYWg3AQTH17CFGsujVaGFEq+UrZXBFFRUob71 eRBHP45aC7DVRAmOKC2UHq7F9PpTMn6KJFUkYcBxku+9jaDX6VcAHw91zLK3E/ALo0Dd N0ROUPbwPN/BLtCj5yFLrnKZm4qO8Lhgb2za4cKJ7cfr5dzxRWWU5AgzAq4mL7atauti 9ijQ== MIME-Version: 1.0 X-Received: by 10.42.111.68 with SMTP id t4mr31692309icp.36.1429111565152; Wed, 15 Apr 2015 08:26:05 -0700 (PDT) Received: by 10.107.158.20 with HTTP; Wed, 15 Apr 2015 08:26:05 -0700 (PDT) In-Reply-To: <552E824C.5080603@mail.bg> References: <355BE46A91031048906B695426A8D8E616B7BE37@DEFTHW99EH4MSX.ww902.siemens.net> <552E63F1.9090406@windriver.com> <552E824C.5080603@mail.bg> Date: Wed, 15 Apr 2015 11:26:05 -0400 Message-ID: From: Bruce Ashfield To: Nikolay Dimitrov Cc: "yocto@yoctoproject.org" , Patches and discussions about the oe-core layer Subject: Re: [yocto] Move device tree generation from include file to bbclass X-BeenThere: openembedded-core@lists.openembedded.org X-Mailman-Version: 2.1.12 Precedence: list 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, 15 Apr 2015 15:26:45 -0000 Content-Type: text/plain; charset=UTF-8 On Wed, Apr 15, 2015 at 11:22 AM, Nikolay Dimitrov wrote: > 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. That is obvious. My questions are around "why". There's no big technical advantage, and if you remove that existing file, you break existing recipes. Which means you need to leave a stub in place. So without a technical advantage, it's churn for the sake of churn. Bruce > >> 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 > > -- > _______________________________________________ > yocto mailing list > yocto@yoctoproject.org > https://lists.yoctoproject.org/listinfo/yocto -- "Thou shalt not follow the NULL pointer, for chaos and madness await thee at its end"