From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751846AbeEDVxG (ORCPT ); Fri, 4 May 2018 17:53:06 -0400 Received: from mail.micronovasrl.com ([212.103.203.10]:58020 "EHLO mail.micronovasrl.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751741AbeEDVxD (ORCPT ); Fri, 4 May 2018 17:53:03 -0400 Authentication-Results: mail.micronovasrl.com (amavisd-new); dkim=pass reason="pass (just generated, assumed good)" header.d=micronovasrl.com X-Spam-Flag: NO X-Spam-Score: -2.9 Subject: Re: [PATCH 7/7] ARM: dts: sun7i: Add dts file for the A20-linova1-7 HMI To: Maxime Ripard Cc: Thierry Reding , David Airlie , Chen-Yu Tsai , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org References: <1521662593-25468-1-git-send-email-giulio.benetti@micronovasrl.com> <1521662593-25468-7-git-send-email-giulio.benetti@micronovasrl.com> <20180322180508.my64gobhh5rc2x2m@flea> <8ef3b259-03b4-6987-286e-36ff627a8b76@micronovasrl.com> <20180424084137.7xfwji2gcibxavvt@flea> <03a02abb-e95c-b4ec-748f-907c0af67969@micronovasrl.com> <20180425184016.xktppxw7egddr7li@flea> <42feccc9-1d09-9ff2-3ccc-1dea63bacfb6@micronovasrl.com> <839d2560-0250-9b3a-8019-4e83d9e931e2@micronovasrl.com> <20180504080652.dniwaqqhbeuknp7y@flea> From: Giulio Benetti Message-ID: Date: Fri, 4 May 2018 23:52:59 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <20180504080652.dniwaqqhbeuknp7y@flea> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Language: it Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Maxime! Il 04/05/2018 10:06, Maxime Ripard ha scritto: > Hi, > > On Wed, May 02, 2018 at 06:41:34PM +0200, Giulio Benetti wrote: >>>> You don't have to handcode the fragments anymore with the new syntax, >>>> and U-Boot makes it really trivial to use if you use the FIT image >>>> format to have multiple overlays bundled in the same image. You can >>>> choose to apply them dynamically, for example based on an EEPROM or >>>> some other metric to see which combination you have. >>> >>> Ah, this is interesting. I'm going to experiment with that. >>> >> >> I'm struggling against this, I don't really know how to proceed, >> except keeping monolithic dts files including other dtsi files. >> >> About dt-overlays I've tried to look around lot of time, >> but the only thing I've found is this: >> https://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers.git/tree/arch/arm/boot/dts?h=topic/renesas-overlays >> >> where they use .dtso tagging them as "/plugin/;" >> and compile all .dtso found in dts folder. >> Then they obtain .dtbo files that should be the dt-overlays we have spoken >> about right? > > Yes. You don't have to do that though, you can just rely on dtc to > compile them, outside of the linux build system. > >> What I can't understand is if there's a real standard at this time to >> follow, because on renesas-driver they use their way to handle all .dtso >> files, but on mainline there seems to be nothing about that. > > I'm not sure what you mean here. It's just fragments of device tree, > that have to be compiled using dtc, that's it. You can use the Linux > build system infrastructure to do that, or you can build your own > simpler one. That's really up to you. See for example > https://github.com/NextThingCo/CHIP-dt-overlays/blob/master/Makefile > > (even though the overlays themselves use the legacy syntax and > shouldn't really be used an examples) Everything works now! Thank you very much! I've setted up a Repo on Github to give an example on how make it work with no pain: https://github.com/micronovasrl/linova-dtoverlays At the moment it's a mess all around, but it's working and give an idea on how to make it work. Though I'm going to clean it up well as a base for linova dtoverlays. Ah, btw, can you confirm me that base dts file must be compiled outside kernel with: dtc -@ .... Otherwise as in-tree dts with make dtbs "-@" argument is not passed. Right? Thank you a lot for your help and time again! Best regards! -- Giulio Benetti CTO MICRONOVA SRL Sede: Via A. Niedda 3 - 35010 Vigonza (PD) Tel. 049/8931563 - Fax 049/8931346 Cod.Fiscale - P.IVA 02663420285 Capitale Sociale € 26.000 i.v. Iscritta al Reg. Imprese di Padova N. 02663420285 Numero R.E.A. 258642