From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Herring Subject: Re: [RESEND PATCHv2 1/4] ARM: dts: add support for building DT overlays Date: Wed, 5 Sep 2018 16:13:23 -0500 Message-ID: References: <1535719666-13595-1-git-send-email-t-kristo@ti.com> <1536048344-9995-1-git-send-email-t-kristo@ti.com> <1536048344-9995-2-git-send-email-t-kristo@ti.com> <71d48595-f40f-acce-2660-ce1630ffc398@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:To:Subject:Message-ID:Date:From: In-Reply-To:References:MIME-Version:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=Yt9Ih6a6V60D51ieNCx0Z76U6WnhhlvYD/6NXdhyl7o=; b=uv1makpfx6ITZk SHUdGO31wni1Jk6Giv7zMu9TbPn/D//yGlMXeGmxJayjDT4H7gTw4F0S6OcJcd/u5GlMeRj/UC81h yJx5wqSjD2sGeOA4KVNu23p8z48Ol6uL9mMIM6jsCo6KH79E/rXXmhMQsJa9PVpD91TRwtBodV/k4 jQY7e0MTDBK50fWBahXzQ0UAVxLZmZSxr4mIF2i8rOtWSJ17JVJLVMM+CrA1owSqBxHKzjaTnGoDG ZU6GuwCvGD6cmh1dWS/ysJaF2FYXfqF8B9SUKbNIjDQzRQrNsWh+58r3UseyEZBaLETFvvWl7Zsvr wUzfaaf/Wd30J5RyAnFw==; DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1536182015; bh=EYIVMaKYVuW4/beCkFbFKivOg85Uep1xjI6fycHyLvQ=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=S42lHbYxlp/1vG1xYnQoqM/YyyvhqWf86xFSSLr35A/YKwaHsXLDHzSdG3YSMx8PD arGi2F8fSpJ+3GMAWtgSPlOuO54CCK7Upa5ol8vMPLuQ60zSlSOwUzSSzdBYKK9o0f nOXb5SUxadpxoXRzNUzkPfZ30lFmSscPtDoTRUv4= In-Reply-To: <71d48595-f40f-acce-2660-ce1630ffc398@gmail.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Frank Rowand Cc: Mark Rutland , devicetree@vger.kernel.org, Tony Lindgren , Catalin Marinas , Will Deacon , Russell King , Tero Kristo , Devicetree Compiler , "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" On Wed, Sep 5, 2018 at 3:36 PM Frank Rowand wrote: > > +cc: devicetree-compiler@vger.kernel.org > > For context on the device-tree compiler list, this patch is for > the Linux kernel. > > On 09/04/18 01:05, Tero Kristo wrote: > > Add simple support for building DT overlays. This just compiles any > > given .dtso file under the base arch/arm/boot/dts directory into > > a .dtbo. > > > > Signed-off-by: Tero Kristo > > --- > > arch/arm/Makefile | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/arch/arm/Makefile b/arch/arm/Makefile > > index d1516f8..ab555a0 100644 > > --- a/arch/arm/Makefile > > +++ b/arch/arm/Makefile > > @@ -339,7 +339,7 @@ $(BOOT_TARGETS): vmlinux > > $(INSTALL_TARGETS): > > $(Q)$(MAKE) $(build)=$(boot) MACHINE=$(MACHINE) $@ > > > > -%.dtb: | scripts > > +%.dtb %.dtbo: | scripts This will need to change with my rework of the DT build rules[1]. > > $(Q)$(MAKE) $(build)=$(boot)/dts MACHINE=$(MACHINE) $(boot)/dts/$@ > > > > PHONY += dtbs dtbs_install > > > > The idea of adding knowledge of .dtso and .dtbo files to the dtc > compiler, but that idea and the related patches have fallen by > the wayside. > > Current overlay sources and blobs are properly handled by dtc when > they are .dts and .dtb files. > > If the dtc compiler is updated with knowledge of .dtso and .dtbo > then these changes would be needed. At the moment the distinction > of a .dtso and .dtbo is a naming convention that provides a clue > about the intended use of the file. But dtc does not know these > file name extensions, requiring a specific flag to tell dtc to > treat them as .dts or .dtb files. I think the negative outweighs > the positive for this patch. I don't follow what you are proposing. We should decide on a convention though. We shouldn't need .dtso because that is identified with the /plugin/ tag. Distinguishing overlay dtbs with .dtbo seems like a good idea though. Rob [1] https://lkml.org/lkml/2018/8/21/770