From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomasz Figa Subject: Re: [PATCH 5/6] ARM: dts: Add basic dts include files for Samsung S3C64xx SoCs Date: Fri, 25 Jan 2013 11:08:01 -0800 (PST) Message-ID: <3747315.IyCCRDXgbD@flatron> References: <1358039458-31960-1-git-send-email-tomasz.figa@gmail.com> <20130114150531.GE21142@e102568-lin.cambridge.arm.com> <20130116105957.GA1963@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: Received: from mail-ea0-f180.google.com ([209.85.215.180]:33019 "EHLO mail-ea0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756789Ab3AYTIE (ORCPT ); Fri, 25 Jan 2013 14:08:04 -0500 Received: by mail-ea0-f180.google.com with SMTP id c1so284766eaa.25 for ; Fri, 25 Jan 2013 11:08:02 -0800 (PST) In-Reply-To: <20130116105957.GA1963@linaro.org> Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: Dave Martin Cc: Lorenzo Pieralisi , Mark Rutland , "linux-samsung-soc@vger.kernel.org" , "kgene.kim@samsung.com" , "linux@arm.linux.org.uk" , "kwangwoo.lee@gmail.com" , "devicetree-discuss@lists.ozlabs.org" , "broonie@opensource.wolfsonmicro.com" , "mcuelenaere@gmail.com" , "augulis.darius@gmail.com" , "linux-arm-kernel@lists.infradead.org" Hi, On Wednesday 16 of January 2013 10:59:57 Dave Martin wrote: > On Mon, Jan 14, 2013 at 03:05:32PM +0000, Lorenzo Pieralisi wrote: > > On Mon, Jan 14, 2013 at 02:48:41PM +0000, Mark Rutland wrote: > > > Hello, > > > > > > This all looks good. I just have a couple of comments about the cpus > > > node.> > > > > On Sun, Jan 13, 2013 at 01:10:57AM +0000, Tomasz Figa wrote: > > > > This patch adds basic device tree definitions for Samsung S3C64xx > > > > SoCs. > > > > > > > > Since all the SoCs in the series are very similar, the files are > > > > created hierarchically - one file for the whole series and then > > > > separate files for particular SoCs including the common one. > > > > > > > > Signed-off-by: Tomasz Figa > > > > > > [...] > > > > > > > diff --git a/arch/arm/boot/dts/s3c64xx.dtsi > > > > b/arch/arm/boot/dts/s3c64xx.dtsi new file mode 100644 > > > > index 0000000..55d6e08 > > > > --- /dev/null > > > > +++ b/arch/arm/boot/dts/s3c64xx.dtsi > > > > @@ -0,0 +1,97 @@ > > > > +/* > > > > + * Samsung's S3C64xx SoC series common device tree source > > > > + * > > > > + * Copyright (c) 2013 Tomasz Figa > > > > + * > > > > + * Samsung's S3C64xx SoC series device nodes are listed in this > > > > file. > > > > + * Particular SoCs from S3C64xx series can include this file and > > > > provide + * values for SoCs specfic bindings. > > > > + * > > > > + * Note: This file does not include device nodes for all the > > > > controllers in + * S3C64xx SoCs. As device tree coverage for > > > > S3C64xx increases, additional + * nodes can be added to this > > > > file. > > > > + * > > > > + * This program is free software; you can redistribute it and/or > > > > modify + * it under the terms of the GNU General Public License > > > > version 2 as + * published by the Free Software Foundation. > > > > + */ > > > > + > > > > +/include/ "skeleton.dtsi" > > > > + > > > > +/ { > > > > + cpus { > > > > + cpu@0 { > > > > + compatible = "arm,arm1176jzf-s"; > > > > + }; > > > > + }; > > > > > > You can drop the unit address from the cpu node - it's meant to be > > > there to differentiate multiple nodes (and is supposed to match the > > > reg property, which the 1176jzf-s can't have, as it doesn't have an > > > MPIDR). > > > > Well, this is a point that I should consider since the kernel docs I > > wrote are misleading, they require the reg property that can not be > > there on UP. True, MPIDR does not exist in this case, but I have to > > document this in the bindings since it is unclear. > > > > > Also, "arm,arm1176jzf-s" isn't listed in the binding doc. There was > > > a question about how to maintain this list [1], but I can't seem to > > > find a conclusion, if any were reached. It might be worth > > > appending "arm,arm1176" to the compatible list for the cpu node in > > > case we want to enable something via dt for all 1176 variations. > > > > > > Dave, Lorenzo, any thoughts? > > > > Eh, frankly I do not know how to handle this. Either we add a > > compatible string to the bindings anytime a DT gets merged in the > > kernel but how to maintain it, it has to be defined. Happy to hear > > some feedback on this. > > Well, the number of CPU types does not grow rapidly. It will be much > less than one per SoC -- so keeping the list up to date shouldn't be > that much effort. > > For ARM1176JZF-S, it could make sense for the comatible list to be > > "arm,arm1176jzf-s", "arm,arm1176" > > ...since the differences between 1176 variants are software probeable > (i.e., whether there is an FPU or not). AFAIK the J, Z apply to all > ARM1176, and the -S (synthesisable RTL) is nothing to do with software. > The kernel probably only really needs to know "arm,arm1176". OK. So the conclusion is that I should change the cpus node to following: cpus { cpu { compatible = "arm,arm1176jzf-s", "arm,arm1176"; }; }; Am I right? Best regards, Tomasz From mboxrd@z Thu Jan 1 00:00:00 1970 From: tomasz.figa@gmail.com (Tomasz Figa) Date: Fri, 25 Jan 2013 11:08:01 -0800 (PST) Subject: [PATCH 5/6] ARM: dts: Add basic dts include files for Samsung S3C64xx SoCs In-Reply-To: <20130116105957.GA1963@linaro.org> References: <1358039458-31960-1-git-send-email-tomasz.figa@gmail.com> <20130114150531.GE21142@e102568-lin.cambridge.arm.com> <20130116105957.GA1963@linaro.org> Message-ID: <3747315.IyCCRDXgbD@flatron> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi, On Wednesday 16 of January 2013 10:59:57 Dave Martin wrote: > On Mon, Jan 14, 2013 at 03:05:32PM +0000, Lorenzo Pieralisi wrote: > > On Mon, Jan 14, 2013 at 02:48:41PM +0000, Mark Rutland wrote: > > > Hello, > > > > > > This all looks good. I just have a couple of comments about the cpus > > > node.> > > > > On Sun, Jan 13, 2013 at 01:10:57AM +0000, Tomasz Figa wrote: > > > > This patch adds basic device tree definitions for Samsung S3C64xx > > > > SoCs. > > > > > > > > Since all the SoCs in the series are very similar, the files are > > > > created hierarchically - one file for the whole series and then > > > > separate files for particular SoCs including the common one. > > > > > > > > Signed-off-by: Tomasz Figa > > > > > > [...] > > > > > > > diff --git a/arch/arm/boot/dts/s3c64xx.dtsi > > > > b/arch/arm/boot/dts/s3c64xx.dtsi new file mode 100644 > > > > index 0000000..55d6e08 > > > > --- /dev/null > > > > +++ b/arch/arm/boot/dts/s3c64xx.dtsi > > > > @@ -0,0 +1,97 @@ > > > > +/* > > > > + * Samsung's S3C64xx SoC series common device tree source > > > > + * > > > > + * Copyright (c) 2013 Tomasz Figa > > > > + * > > > > + * Samsung's S3C64xx SoC series device nodes are listed in this > > > > file. > > > > + * Particular SoCs from S3C64xx series can include this file and > > > > provide + * values for SoCs specfic bindings. > > > > + * > > > > + * Note: This file does not include device nodes for all the > > > > controllers in + * S3C64xx SoCs. As device tree coverage for > > > > S3C64xx increases, additional + * nodes can be added to this > > > > file. > > > > + * > > > > + * This program is free software; you can redistribute it and/or > > > > modify + * it under the terms of the GNU General Public License > > > > version 2 as + * published by the Free Software Foundation. > > > > + */ > > > > + > > > > +/include/ "skeleton.dtsi" > > > > + > > > > +/ { > > > > + cpus { > > > > + cpu at 0 { > > > > + compatible = "arm,arm1176jzf-s"; > > > > + }; > > > > + }; > > > > > > You can drop the unit address from the cpu node - it's meant to be > > > there to differentiate multiple nodes (and is supposed to match the > > > reg property, which the 1176jzf-s can't have, as it doesn't have an > > > MPIDR). > > > > Well, this is a point that I should consider since the kernel docs I > > wrote are misleading, they require the reg property that can not be > > there on UP. True, MPIDR does not exist in this case, but I have to > > document this in the bindings since it is unclear. > > > > > Also, "arm,arm1176jzf-s" isn't listed in the binding doc. There was > > > a question about how to maintain this list [1], but I can't seem to > > > find a conclusion, if any were reached. It might be worth > > > appending "arm,arm1176" to the compatible list for the cpu node in > > > case we want to enable something via dt for all 1176 variations. > > > > > > Dave, Lorenzo, any thoughts? > > > > Eh, frankly I do not know how to handle this. Either we add a > > compatible string to the bindings anytime a DT gets merged in the > > kernel but how to maintain it, it has to be defined. Happy to hear > > some feedback on this. > > Well, the number of CPU types does not grow rapidly. It will be much > less than one per SoC -- so keeping the list up to date shouldn't be > that much effort. > > For ARM1176JZF-S, it could make sense for the comatible list to be > > "arm,arm1176jzf-s", "arm,arm1176" > > ...since the differences between 1176 variants are software probeable > (i.e., whether there is an FPU or not). AFAIK the J, Z apply to all > ARM1176, and the -S (synthesisable RTL) is nothing to do with software. > The kernel probably only really needs to know "arm,arm1176". OK. So the conclusion is that I should change the cpus node to following: cpus { cpu { compatible = "arm,arm1176jzf-s", "arm,arm1176"; }; }; Am I right? Best regards, Tomasz