From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jon Hunter Subject: Re: [PATCH 3/4] ARM: tegra: nyan-big: Include compatible revisions for proper detection Date: Wed, 21 Sep 2016 10:15:15 +0100 Message-ID: <5461eb20-9372-7fa1-0e48-3d0143393b8c@nvidia.com> References: <20160828173246.32621-1-contact@paulk.fr> <20160828173246.32621-3-contact@paulk.fr> <1474394004.1215.2.camel@paulk.fr> <1474394544.1215.13.camel@paulk.fr> <6501341f-e14c-4876-dcb7-60a33b7621c4@nvidia.com> <1474443809.1239.4.camel@paulk.fr> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1474443809.1239.4.camel@paulk.fr> Sender: linux-kernel-owner@vger.kernel.org To: Paul Kocialkowski , linux-kernel@vger.kernel.org Cc: devicetree@vger.kernel.org, Stephen Warren , Thierry Reding , linux-tegra@vger.kernel.org, Alexandre Courbot , linux-arm-kernel@lists.infradead.org List-Id: linux-tegra@vger.kernel.org On 21/09/16 08:43, Paul Kocialkowski wrote: ... >>>>>>> Depthcharge (the payload used with cros devices) will attempt to >>>>>>> detect >>>>>>> boards using their revision. This includes all the known revisions >>>>>>> for >>>>>>> the nyan-big board so that the dtb can be selected preferably. >>>>>> >>>>>> May be I am missing something here, but for the mainline there is only >>>>>> one dtb available and so why is this needed for the mainline? >>>>> >>>>> There is indeed a single dts in mainline, but depthcharge will use the >>>>> revision >>>>> to match the compatible string (e.g. it will look for google,nyan-big- >>>>> rev5, >>>>> not >>>>> google,nyan-big), so we need to list them all in that single dts. >>>>> Otherwise, >>>>> depthcharge will fall back to the default config, which may or may not >>>>> be >>>>> suitable for nyan. >>>> >>>> Is tegra124-nyan-big.dtb not the default? >>> >>> You can't expect that to always be the case. The image format allows many >>> different dts to be provided, so I could easily build with >>> multi_v7_defconfig >>> and have various dts for various devices in the same image, and just select >>> a >>> random one as default. >> >> Really? Sounds odd. I was hoping that tegra124-nyan-big.dtb would be a >> catch all. I meant I was hoping that compatible = "google,nyan-big" would be the catchall not the dtb file name ;-) > Yes, the image format (FIT) allows specifying multiple dtb and zImage > combinations in the same image[0]. Yes I am aware of that. Typically, I have been testing using a FIT image with single zImage and dtb. Hence no problems. So are you wanting to create a FIT image to support multiple boards and use the single FIT image for all? If so then I can see why you want this. Again please describe the motivation for the changes in the changelog so it is clear why we are adding this. Cheers Jon -- nvpublic From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932763AbcIUJPc (ORCPT ); Wed, 21 Sep 2016 05:15:32 -0400 Received: from hqemgate15.nvidia.com ([216.228.121.64]:4862 "EHLO hqemgate15.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932337AbcIUJP2 (ORCPT ); Wed, 21 Sep 2016 05:15:28 -0400 X-PGP-Universal: processed; by hqnvupgp07.nvidia.com on Wed, 21 Sep 2016 02:09:50 -0700 Subject: Re: [PATCH 3/4] ARM: tegra: nyan-big: Include compatible revisions for proper detection To: Paul Kocialkowski , References: <20160828173246.32621-1-contact@paulk.fr> <20160828173246.32621-3-contact@paulk.fr> <1474394004.1215.2.camel@paulk.fr> <1474394544.1215.13.camel@paulk.fr> <6501341f-e14c-4876-dcb7-60a33b7621c4@nvidia.com> <1474443809.1239.4.camel@paulk.fr> CC: , Stephen Warren , Thierry Reding , , Alexandre Courbot , From: Jon Hunter Message-ID: <5461eb20-9372-7fa1-0e48-3d0143393b8c@nvidia.com> Date: Wed, 21 Sep 2016 10:15:15 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: <1474443809.1239.4.camel@paulk.fr> X-Originating-IP: [10.21.132.118] X-ClientProxiedBy: DRUKMAIL101.nvidia.com (10.25.59.19) To UKMAIL101.nvidia.com (10.26.138.13) Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 21/09/16 08:43, Paul Kocialkowski wrote: ... >>>>>>> Depthcharge (the payload used with cros devices) will attempt to >>>>>>> detect >>>>>>> boards using their revision. This includes all the known revisions >>>>>>> for >>>>>>> the nyan-big board so that the dtb can be selected preferably. >>>>>> >>>>>> May be I am missing something here, but for the mainline there is only >>>>>> one dtb available and so why is this needed for the mainline? >>>>> >>>>> There is indeed a single dts in mainline, but depthcharge will use the >>>>> revision >>>>> to match the compatible string (e.g. it will look for google,nyan-big- >>>>> rev5, >>>>> not >>>>> google,nyan-big), so we need to list them all in that single dts. >>>>> Otherwise, >>>>> depthcharge will fall back to the default config, which may or may not >>>>> be >>>>> suitable for nyan. >>>> >>>> Is tegra124-nyan-big.dtb not the default? >>> >>> You can't expect that to always be the case. The image format allows many >>> different dts to be provided, so I could easily build with >>> multi_v7_defconfig >>> and have various dts for various devices in the same image, and just select >>> a >>> random one as default. >> >> Really? Sounds odd. I was hoping that tegra124-nyan-big.dtb would be a >> catch all. I meant I was hoping that compatible = "google,nyan-big" would be the catchall not the dtb file name ;-) > Yes, the image format (FIT) allows specifying multiple dtb and zImage > combinations in the same image[0]. Yes I am aware of that. Typically, I have been testing using a FIT image with single zImage and dtb. Hence no problems. So are you wanting to create a FIT image to support multiple boards and use the single FIT image for all? If so then I can see why you want this. Again please describe the motivation for the changes in the changelog so it is clear why we are adding this. Cheers Jon -- nvpublic From mboxrd@z Thu Jan 1 00:00:00 1970 From: jonathanh@nvidia.com (Jon Hunter) Date: Wed, 21 Sep 2016 10:15:15 +0100 Subject: [PATCH 3/4] ARM: tegra: nyan-big: Include compatible revisions for proper detection In-Reply-To: <1474443809.1239.4.camel@paulk.fr> References: <20160828173246.32621-1-contact@paulk.fr> <20160828173246.32621-3-contact@paulk.fr> <1474394004.1215.2.camel@paulk.fr> <1474394544.1215.13.camel@paulk.fr> <6501341f-e14c-4876-dcb7-60a33b7621c4@nvidia.com> <1474443809.1239.4.camel@paulk.fr> Message-ID: <5461eb20-9372-7fa1-0e48-3d0143393b8c@nvidia.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 21/09/16 08:43, Paul Kocialkowski wrote: ... >>>>>>> Depthcharge (the payload used with cros devices) will attempt to >>>>>>> detect >>>>>>> boards using their revision. This includes all the known revisions >>>>>>> for >>>>>>> the nyan-big board so that the dtb can be selected preferably. >>>>>> >>>>>> May be I am missing something here, but for the mainline there is only >>>>>> one dtb available and so why is this needed for the mainline? >>>>> >>>>> There is indeed a single dts in mainline, but depthcharge will use the >>>>> revision >>>>> to match the compatible string (e.g. it will look for google,nyan-big- >>>>> rev5, >>>>> not >>>>> google,nyan-big), so we need to list them all in that single dts. >>>>> Otherwise, >>>>> depthcharge will fall back to the default config, which may or may not >>>>> be >>>>> suitable for nyan. >>>> >>>> Is tegra124-nyan-big.dtb not the default? >>> >>> You can't expect that to always be the case. The image format allows many >>> different dts to be provided, so I could easily build with >>> multi_v7_defconfig >>> and have various dts for various devices in the same image, and just select >>> a >>> random one as default. >> >> Really? Sounds odd. I was hoping that tegra124-nyan-big.dtb would be a >> catch all. I meant I was hoping that compatible = "google,nyan-big" would be the catchall not the dtb file name ;-) > Yes, the image format (FIT) allows specifying multiple dtb and zImage > combinations in the same image[0]. Yes I am aware of that. Typically, I have been testing using a FIT image with single zImage and dtb. Hence no problems. So are you wanting to create a FIT image to support multiple boards and use the single FIT image for all? If so then I can see why you want this. Again please describe the motivation for the changes in the changelog so it is clear why we are adding this. Cheers Jon -- nvpublic