[{"id":3411299,"web_url":"http://patchwork.ozlabs.org/comment/3411299/","msgid":"","list_archive_url":null,"date":"2024-11-08T16:03:31","subject":"Re: [PATCH v2 5/6] of: Add #address-cells/#size-cells in the\n device-tree root empty node","submitter":{"id":62529,"url":"http://patchwork.ozlabs.org/api/people/62529/","name":"Rob Herring (Arm)","email":"robh@kernel.org"},"content":"On Fri, Nov 8, 2024 at 8:36 AM Herve Codina wrote:\n>\n> On systems where ACPI is enabled or when a device-tree is not passed to\n> the kernel by the bootloader, a device-tree root empty node is created.\n> This device-tree root empty node doesn't have the #address-cells and the\n\nand the?\n\n> This leads to the use of the default address cells and size cells values\n> which are defined in the code to 1 for address cells and 1 for size cells\n\nMissing period.\n\n>\n> According to the devicetree specification and the OpenFirmware standard\n> (IEEE 1275-1994) the default value for #address-cells should be 2.\n>\n> Also, according to the devicetree specification, the #address-cells and\n> the #size-cells are required properties in the root node.\n>\n> Modern implementation should have the #address-cells and the #size-cells\n> properties set and should not rely on default values.\n>\n> On x86, this root empty node is used and the code default values are\n> used.\n>\n> In preparation of the support for device-tree overlay on PCI devices\n> feature on x86 (i.e. the creation of the PCI root bus device-tree node),\n> the default value for #address-cells needs to be updated. Indeed, on\n> x86_64, addresses are on 64bits and the upper part of an address is\n> needed for correct address translations. On x86_32 having the default\n> value updated does not lead to issues while the uppert part of a 64bits\n\nupper\n\n> address is zero.\n>\n> Changing the default value for all architectures may break device-tree\n> compatibility. Indeed, existing dts file without the #address-cells\n> property set in the root node will not be compatible with this\n> modification.\n>\n> Instead of updating default values, add required #address-cells and\n\nand?\n\n>\n> Signed-off-by: Herve Codina \n> ---\n> drivers/of/empty_root.dts | 8 +++++++-\n> 1 file changed, 7 insertions(+), 1 deletion(-)\n>\n> diff --git a/drivers/of/empty_root.dts b/drivers/of/empty_root.dts\n> index cf9e97a60f48..5017579f34dc 100644\n> --- a/drivers/of/empty_root.dts\n> +++ b/drivers/of/empty_root.dts\n> @@ -2,5 +2,11 @@\n> /dts-v1/;\n>\n> / {\n> -\n> + /*\n> + * #address-cells/#size-cells are required properties at root node\n> + * according to the devicetree specification. Use same values as default\n> + * values mentioned for #address-cells/#size-cells properties.\n\nWhich default? We have multiple...\n\nThere's also dtc's idea of default which IIRC is 2 and 1 like OpenFirmware.\n\n> + */\n> + #address-cells = <0x02>;\n> + #size-cells = <0x01>;\n\nI think we should just do 2 cells for size.\n\nRob","headers":{"Return-Path":"\n ","X-Original-To":["incoming@patchwork.ozlabs.org","linux-pci@vger.kernel.org"],"Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256\n header.s=k20201202 header.b=s5A5yZT1;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=139.178.88.99; helo=sv.mirrors.kernel.org;\n envelope-from=linux-pci+bounces-16339-incoming=patchwork.ozlabs.org@vger.kernel.org;\n receiver=patchwork.ozlabs.org)","smtp.subspace.kernel.org;\n\tdkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org\n header.b=\"s5A5yZT1\"","smtp.subspace.kernel.org;\n arc=none smtp.client-ip=10.30.226.201"],"Received":["from sv.mirrors.kernel.org (sv.mirrors.kernel.org [139.178.88.99])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange X25519 server-signature ECDSA (secp384r1))\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4XlNzp0S2Nz1xy0\n\tfor ; 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Fri, 08 Nov 2024\n 08:03:42 -0800 (PST)","Precedence":"bulk","X-Mailing-List":"linux-pci@vger.kernel.org","List-Id":"","List-Subscribe":"","List-Unsubscribe":"","MIME-Version":"1.0","References":"<20241108143600.756224-1-herve.codina@bootlin.com>\n <20241108143600.756224-6-herve.codina@bootlin.com>","In-Reply-To":"<20241108143600.756224-6-herve.codina@bootlin.com>","From":"Rob Herring ","Date":"Fri, 8 Nov 2024 10:03:31 -0600","X-Gmail-Original-Message-ID":"\n ","Message-ID":"\n ","Subject":"Re: [PATCH v2 5/6] of: Add #address-cells/#size-cells in the\n device-tree root empty node","To":"Herve Codina ","Cc":"Greg Kroah-Hartman ,\n \"Rafael J. Wysocki\" ,\n\tSaravana Kannan , Bjorn Helgaas ,\n\tLizhi Hou , linux-kernel@vger.kernel.org,\n\tdevicetree@vger.kernel.org, linux-pci@vger.kernel.org,\n\tAllan Nielsen ,\n Horatiu Vultur ,\n\tSteen Hegelund ,\n\tThomas Petazzoni ","Content-Type":"text/plain; charset=\"UTF-8\"","Content-Transfer-Encoding":"quoted-printable"}},{"id":3411310,"web_url":"http://patchwork.ozlabs.org/comment/3411310/","msgid":"<20241108172946.7233825e@bootlin.com>","list_archive_url":null,"date":"2024-11-08T16:29:46","subject":"Re: [PATCH v2 5/6] of: Add #address-cells/#size-cells in the\n device-tree root empty node","submitter":{"id":81983,"url":"http://patchwork.ozlabs.org/api/people/81983/","name":"Herve Codina","email":"herve.codina@bootlin.com"},"content":"Hi Rob,\n\nOn Fri, 8 Nov 2024 10:03:31 -0600\nRob Herring wrote:\n\n> On Fri, Nov 8, 2024 at 8:36 AM Herve Codina wrote:\n> >\n> > On systems where ACPI is enabled or when a device-tree is not passed to\n> > the kernel by the bootloader, a device-tree root empty node is created.\n> > This device-tree root empty node doesn't have the #address-cells and the \n> \n> and the?\n\n#size-cells properties.\n\nWill be updated.\n\n> \n> > This leads to the use of the default address cells and size cells values\n> > which are defined in the code to 1 for address cells and 1 for size cells \n> \n> Missing period.\n\nWill be updated.\n\n> \n> >\n> > According to the devicetree specification and the OpenFirmware standard\n> > (IEEE 1275-1994) the default value for #address-cells should be 2.\n> >\n> > Also, according to the devicetree specification, the #address-cells and\n> > the #size-cells are required properties in the root node.\n> >\n> > Modern implementation should have the #address-cells and the #size-cells\n> > properties set and should not rely on default values.\n> >\n> > On x86, this root empty node is used and the code default values are\n> > used.\n> >\n> > In preparation of the support for device-tree overlay on PCI devices\n> > feature on x86 (i.e. the creation of the PCI root bus device-tree node),\n> > the default value for #address-cells needs to be updated. Indeed, on\n> > x86_64, addresses are on 64bits and the upper part of an address is\n> > needed for correct address translations. On x86_32 having the default\n> > value updated does not lead to issues while the uppert part of a 64bits \n> \n> upper\n\nWill be updated.\n\n> \n> > address is zero.\n> >\n> > Changing the default value for all architectures may break device-tree\n> > compatibility. Indeed, existing dts file without the #address-cells\n> > property set in the root node will not be compatible with this\n> > modification.\n> >\n> > Instead of updating default values, add required #address-cells and \n> \n> and?\n\n#size-cells properties in the device-tree empty root node.\n\nWill be updated.\n\n> \n> >\n> > Signed-off-by: Herve Codina \n> > ---\n> > drivers/of/empty_root.dts | 8 +++++++-\n> > 1 file changed, 7 insertions(+), 1 deletion(-)\n> >\n> > diff --git a/drivers/of/empty_root.dts b/drivers/of/empty_root.dts\n> > index cf9e97a60f48..5017579f34dc 100644\n> > --- a/drivers/of/empty_root.dts\n> > +++ b/drivers/of/empty_root.dts\n> > @@ -2,5 +2,11 @@\n> > /dts-v1/;\n> >\n> > / {\n> > -\n> > + /*\n> > + * #address-cells/#size-cells are required properties at root node\n> > + * according to the devicetree specification. Use same values as default\n> > + * values mentioned for #address-cells/#size-cells properties. \n> \n> Which default? We have multiple...\n\nI will reword:\n Use values mentioned in the devicetree specification as default values\n for #address-cells and #size-cells properties\n\n\n> \n> There's also dtc's idea of default which IIRC is 2 and 1 like OpenFirmware.\n\nI can re-add this part in the commit log:\n The device tree compiler already uses 2 as default value for address cells\n and 1 for size cells. The powerpc PROM code also use 2 as default value\n for #address-cells and 1 for #size-cells. Modern implementation should\n have the #address-cells and the #size-cells properties set and should\n not rely on default values.\n\nIn your opinion, does it make sense?\n\n> \n> > + */\n> > + #address-cells = <0x02>;\n> > + #size-cells = <0x01>; \n> \n> I think we should just do 2 cells for size.\n\nWhy using 2 for #size-cells?\n\nI understand that allows to have size defined on 64bits but is that needed?\nHow to justify this value here?\n\nBest regards,\nHervé","headers":{"Return-Path":"\n ","X-Original-To":["incoming@patchwork.ozlabs.org","linux-pci@vger.kernel.org"],"Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=bootlin.com header.i=@bootlin.com header.a=rsa-sha256\n header.s=gm1 header.b=ZHNQ5and;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=2604:1380:4601:e00::3; helo=am.mirrors.kernel.org;\n envelope-from=linux-pci+bounces-16340-incoming=patchwork.ozlabs.org@vger.kernel.org;\n receiver=patchwork.ozlabs.org)","smtp.subspace.kernel.org;\n\tdkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com\n header.b=\"ZHNQ5and\"","smtp.subspace.kernel.org;\n arc=none smtp.client-ip=217.70.183.197","smtp.subspace.kernel.org;\n dmarc=pass (p=reject dis=none) header.from=bootlin.com","smtp.subspace.kernel.org;\n spf=pass smtp.mailfrom=bootlin.com"],"Received":["from am.mirrors.kernel.org (am.mirrors.kernel.org\n [IPv6:2604:1380:4601:e00::3])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange X25519 server-signature ECDSA (secp384r1) server-digest SHA384)\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4XlPYN5DKfz1xyS\n\tfor ; Sat, 9 Nov 2024 03:30:00 +1100 (AEDT)","from smtp.subspace.kernel.org (wormhole.subspace.kernel.org\n [52.25.139.140])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))\n\t(No client certificate requested)\n\tby am.mirrors.kernel.org (Postfix) with ESMTPS id 4380A1F23E2E\n\tfor ; Fri, 8 Nov 2024 16:29:58 +0000 (UTC)","from localhost.localdomain (localhost.localdomain [127.0.0.1])\n\tby smtp.subspace.kernel.org (Postfix) with ESMTP id 9640D192584;\n\tFri, 8 Nov 2024 16:29:53 +0000 (UTC)","from relay5-d.mail.gandi.net (relay5-d.mail.gandi.net\n [217.70.183.197])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))\n\t(No client certificate requested)\n\tby smtp.subspace.kernel.org (Postfix) with ESMTPS id 2207F187FE4;\n\tFri, 8 Nov 2024 16:29:49 +0000 (UTC)","by mail.gandi.net (Postfix) with ESMTPSA id 5C1771C0003;\n\tFri, 8 Nov 2024 16:29:47 +0000 (UTC)"],"ARC-Seal":"i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116;\n\tt=1731083393; cv=none;\n b=rXjdTIYs1m8K8FjLzTv583SJms3Nt09WC9zMLPx0wmhSsYZVJDL3qT76Re+ZZyxGjkFHcls0Rdh+dpcNHhJm0CtdVRDdryiUAS3XoOrHxeNWCXn8U0tUpQbvEJLCfgUT1iw/+wvI3JZ4wqWcucWotrjFwu0X0jZfsKeOog42MFE=","ARC-Message-Signature":"i=1; a=rsa-sha256; d=subspace.kernel.org;\n\ts=arc-20240116; t=1731083393; c=relaxed/simple;\n\tbh=DNG0fhk9qlX9wvnac6CmQX+5HHoCd1PixPcukAAxAbQ=;\n\th=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References:\n\t MIME-Version:Content-Type;\n b=FqiL0epFq2Uu9eukWiBlLEcpmygAiqNcHqxFsmu6ZKBW/jYxzuwOVt+VrVN5M1RIyNvMCJH/0/3Cyv09Q/cKDxc4Nq0uHyzp1IZ56HEU6rOeT4/irNUhJWfM8GWu2g08gg7fCYc9+9YZyNYvxjI9ZEH341VuLNVMh56WM2CQ4z0=","ARC-Authentication-Results":"i=1; smtp.subspace.kernel.org;\n dmarc=pass (p=reject dis=none) header.from=bootlin.com;\n spf=pass smtp.mailfrom=bootlin.com;\n dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com\n header.b=ZHNQ5and; arc=none smtp.client-ip=217.70.183.197","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1;\n\tt=1731083388;\n\th=from:from:reply-to:subject:subject:date:date:message-id:message-id:\n\t to:to:cc:cc:mime-version:mime-version:content-type:content-type:\n\t content-transfer-encoding:content-transfer-encoding:\n\t in-reply-to:in-reply-to:references:references;\n\tbh=SNv0XZ9+/yD94EzPzcVjyKNuEO41gbMIYl9M0TKDnlY=;\n\tb=ZHNQ5andb//fQ6/+jxYn/+OPoSdSGOeFUiiZNi6z26S/XjrKcFCTYfH8z0sDGohKEpdDNF\n\tXnsKSi0776p2f/hOyHZtURKABa7emm8YbXZ8I4gEo03qZiV5TKQG+eSoguH/gn6MhfFO+R\n\tkbo4W/uhXmETgZgmaHOIDU12xGRg0e6v7OXTBFl/IEV6pECCnLp7HnjtIfAYw+Us7cF40d\n\tXEeuCyEbOXnIYggWSAQHpihdQhqMl/fxXX9RF5o+C5lLbZYywL8KD8LY5sbGE+JfWhe+DM\n\tYy4CC1NpdwEosL/1GPGaAx8V2MdX6NJsBTvw6c/ZJ7M6n7fwT3CHYWbTa856Pg==","Date":"Fri, 8 Nov 2024 17:29:46 +0100","From":"Herve Codina ","To":"Rob Herring ","Cc":"Greg Kroah-Hartman , \"Rafael J. Wysocki\"\n , Saravana Kannan , Bjorn Helgaas\n , Lizhi Hou ,\n linux-kernel@vger.kernel.org, devicetree@vger.kernel.org,\n linux-pci@vger.kernel.org, Allan Nielsen ,\n Horatiu Vultur , Steen Hegelund\n , Thomas Petazzoni\n ","Subject":"Re: [PATCH v2 5/6] of: Add #address-cells/#size-cells in the\n device-tree root empty node","Message-ID":"<20241108172946.7233825e@bootlin.com>","In-Reply-To":"\n ","References":"<20241108143600.756224-1-herve.codina@bootlin.com>\n\t<20241108143600.756224-6-herve.codina@bootlin.com>\n\t","Organization":"Bootlin","X-Mailer":"Claws Mail 4.3.0 (GTK 3.24.43; x86_64-redhat-linux-gnu)","Precedence":"bulk","X-Mailing-List":"linux-pci@vger.kernel.org","List-Id":"","List-Subscribe":"","List-Unsubscribe":"","MIME-Version":"1.0","Content-Type":"text/plain; charset=UTF-8","Content-Transfer-Encoding":"8bit","X-GND-Sasl":"herve.codina@bootlin.com"}},{"id":3411348,"web_url":"http://patchwork.ozlabs.org/comment/3411348/","msgid":"","list_archive_url":null,"date":"2024-11-08T17:24:36","subject":"Re: [PATCH v2 5/6] of: Add #address-cells/#size-cells in the\n device-tree root empty node","submitter":{"id":62529,"url":"http://patchwork.ozlabs.org/api/people/62529/","name":"Rob Herring (Arm)","email":"robh@kernel.org"},"content":"On Fri, Nov 8, 2024 at 10:29 AM Herve Codina wrote:\n>\n> Hi Rob,\n>\n> On Fri, 8 Nov 2024 10:03:31 -0600\n> Rob Herring wrote:\n>\n> > On Fri, Nov 8, 2024 at 8:36 AM Herve Codina wrote:\n> > >\n> > > On systems where ACPI is enabled or when a device-tree is not passed to\n> > > the kernel by the bootloader, a device-tree root empty node is created.\n> > > This device-tree root empty node doesn't have the #address-cells and the\n\n> > > + /*\n> > > + * #address-cells/#size-cells are required properties at root node\n> > > + * according to the devicetree specification. Use same values as default\n> > > + * values mentioned for #address-cells/#size-cells properties.\n> >\n> > Which default? We have multiple...\n>\n> I will reword:\n> Use values mentioned in the devicetree specification as default values\n> for #address-cells and #size-cells properties\n\nMy point was that \"default\" is meaningless because there are multiple\nsources of what's default.\n\n> >\n> > There's also dtc's idea of default which IIRC is 2 and 1 like OpenFirmware.\n>\n> I can re-add this part in the commit log:\n> The device tree compiler already uses 2 as default value for address cells\n> and 1 for size cells. The powerpc PROM code also use 2 as default value\n> for #address-cells and 1 for #size-cells. Modern implementation should\n> have the #address-cells and the #size-cells properties set and should\n> not rely on default values.\n>\n> In your opinion, does it make sense?\n>\n> >\n> > > + */\n> > > + #address-cells = <0x02>;\n> > > + #size-cells = <0x01>;\n> >\n> > I think we should just do 2 cells for size.\n>\n> Why using 2 for #size-cells?\n>\n> I understand that allows to have size defined on 64bits but is that needed?\n> How to justify this value here?\n\nMost systems are 64-bit today. And *all* ACPI based systems are. Not\nthat the DT has to match 32 vs 64 bit CPU, most of the time it does.\n\nIt also doesn't actually change anything for you because you're going\nto have \"pci\" nodes and the \"ranges\" there takes #size-cells from the\npci node, not the parent.\n\nRob","headers":{"Return-Path":"\n ","X-Original-To":["incoming@patchwork.ozlabs.org","linux-pci@vger.kernel.org"],"Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256\n header.s=k20201202 header.b=NvNERBPH;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=2604:1380:4601:e00::3; helo=am.mirrors.kernel.org;\n envelope-from=linux-pci+bounces-16349-incoming=patchwork.ozlabs.org@vger.kernel.org;\n receiver=patchwork.ozlabs.org)","smtp.subspace.kernel.org;\n\tdkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org\n header.b=\"NvNERBPH\"","smtp.subspace.kernel.org;\n arc=none smtp.client-ip=10.30.226.201"],"Received":["from am.mirrors.kernel.org (am.mirrors.kernel.org\n [IPv6:2604:1380:4601:e00::3])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange X25519 server-signature ECDSA (secp384r1))\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4XlQmx3CHRz1xyS\n\tfor ; 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Wysocki\" ,\n\tSaravana Kannan , Bjorn Helgaas ,\n\tLizhi Hou , linux-kernel@vger.kernel.org,\n\tdevicetree@vger.kernel.org, linux-pci@vger.kernel.org,\n\tAllan Nielsen ,\n Horatiu Vultur ,\n\tSteen Hegelund ,\n\tThomas Petazzoni ","Content-Type":"text/plain; charset=\"UTF-8\"","Content-Transfer-Encoding":"quoted-printable"}},{"id":3411361,"web_url":"http://patchwork.ozlabs.org/comment/3411361/","msgid":"<20241108183958.0f136e01@bootlin.com>","list_archive_url":null,"date":"2024-11-08T17:39:58","subject":"Re: [PATCH v2 5/6] of: Add #address-cells/#size-cells in the\n device-tree root empty node","submitter":{"id":81983,"url":"http://patchwork.ozlabs.org/api/people/81983/","name":"Herve Codina","email":"herve.codina@bootlin.com"},"content":"On Fri, 8 Nov 2024 11:24:36 -0600\nRob Herring wrote:\n\n> On Fri, Nov 8, 2024 at 10:29 AM Herve Codina wrote:\n> >\n> > Hi Rob,\n> >\n> > On Fri, 8 Nov 2024 10:03:31 -0600\n> > Rob Herring wrote:\n> > \n> > > On Fri, Nov 8, 2024 at 8:36 AM Herve Codina wrote: \n> > > >\n> > > > On systems where ACPI is enabled or when a device-tree is not passed to\n> > > > the kernel by the bootloader, a device-tree root empty node is created.\n> > > > This device-tree root empty node doesn't have the #address-cells and the \n> \n> > > > + /*\n> > > > + * #address-cells/#size-cells are required properties at root node\n> > > > + * according to the devicetree specification. Use same values as default\n> > > > + * values mentioned for #address-cells/#size-cells properties. \n> > >\n> > > Which default? We have multiple... \n> >\n> > I will reword:\n> > Use values mentioned in the devicetree specification as default values\n> > for #address-cells and #size-cells properties \n> \n> My point was that \"default\" is meaningless because there are multiple\n> sources of what's default.\n\nI see thanks.\nI will update the code comment.\n\n> \n> > >\n> > > There's also dtc's idea of default which IIRC is 2 and 1 like OpenFirmware. \n> >\n> > I can re-add this part in the commit log:\n> > The device tree compiler already uses 2 as default value for address cells\n> > and 1 for size cells. The powerpc PROM code also use 2 as default value\n> > for #address-cells and 1 for #size-cells. Modern implementation should\n> > have the #address-cells and the #size-cells properties set and should\n> > not rely on default values.\n> >\n> > In your opinion, does it make sense?\n> > \n> > > \n> > > > + */\n> > > > + #address-cells = <0x02>;\n> > > > + #size-cells = <0x01>; \n> > >\n> > > I think we should just do 2 cells for size. \n> >\n> > Why using 2 for #size-cells?\n> >\n> > I understand that allows to have size defined on 64bits but is that needed?\n> > How to justify this value here? \n> \n> Most systems are 64-bit today. And *all* ACPI based systems are. Not\n> that the DT has to match 32 vs 64 bit CPU, most of the time it does.\n> \n> It also doesn't actually change anything for you because you're going\n> to have \"pci\" nodes and the \"ranges\" there takes #size-cells from the\n> pci node, not the parent.\n> \n\nRight.\nI will set:\n #address-cells = <0x02>;\n #size-cells = <0x02>;\n\nBest regards,\nHervé","headers":{"Return-Path":"\n ","X-Original-To":["incoming@patchwork.ozlabs.org","linux-pci@vger.kernel.org"],"Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=bootlin.com header.i=@bootlin.com header.a=rsa-sha256\n header.s=gm1 header.b=NwXAzx19;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=2604:1380:45e3:2400::1; helo=sv.mirrors.kernel.org;\n envelope-from=linux-pci+bounces-16350-incoming=patchwork.ozlabs.org@vger.kernel.org;\n receiver=patchwork.ozlabs.org)","smtp.subspace.kernel.org;\n\tdkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com\n header.b=\"NwXAzx19\"","smtp.subspace.kernel.org;\n arc=none smtp.client-ip=217.70.183.199","smtp.subspace.kernel.org;\n dmarc=pass (p=reject dis=none) header.from=bootlin.com","smtp.subspace.kernel.org;\n spf=pass smtp.mailfrom=bootlin.com"],"Received":["from sv.mirrors.kernel.org (sv.mirrors.kernel.org\n [IPv6:2604:1380:45e3:2400::1])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange X25519 server-signature ECDSA (secp384r1))\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4XlRNr0xwsz1xyM\n\tfor ; Sat, 9 Nov 2024 04:52:44 +1100 (AEDT)","from smtp.subspace.kernel.org (wormhole.subspace.kernel.org\n [52.25.139.140])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))\n\t(No client certificate requested)\n\tby sv.mirrors.kernel.org (Postfix) with ESMTPS id D2B6B2829FE\n\tfor ; Fri, 8 Nov 2024 17:52:42 +0000 (UTC)","from localhost.localdomain (localhost.localdomain [127.0.0.1])\n\tby smtp.subspace.kernel.org (Postfix) with ESMTP id 7BD7620DD7B;\n\tFri, 8 Nov 2024 17:40:10 +0000 (UTC)","from relay9-d.mail.gandi.net (relay9-d.mail.gandi.net\n [217.70.183.199])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))\n\t(No client certificate requested)\n\tby smtp.subspace.kernel.org (Postfix) with ESMTPS id E484E233D6D;\n\tFri, 8 Nov 2024 17:40:06 +0000 (UTC)","by mail.gandi.net (Postfix) with ESMTPSA id E556FFF806;\n\tFri, 8 Nov 2024 17:39:58 +0000 (UTC)"],"ARC-Seal":"i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116;\n\tt=1731087610; cv=none;\n b=Xr5lMqgqbr3Ujd04C2MXQm9BoscjdYKsvoxJZhmx+hwL39pyY6O4z6avXLTRUIEaOC6JJQHHnfHjbmtCVz/1bdDdMm9PGbVwspk+mYqRAj7ue8kg++r8sEzezY3glxTz2IR3FLxCLyset3vMmJ3q0qLnr8Y7dYNGbilgoQEeQXU=","ARC-Message-Signature":"i=1; a=rsa-sha256; d=subspace.kernel.org;\n\ts=arc-20240116; t=1731087610; c=relaxed/simple;\n\tbh=iiARu0Nk8CVwQ3QQGwPP6meCN98PtNxkPO57n5KBjcg=;\n\th=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References:\n\t MIME-Version:Content-Type;\n b=O8XfrDEQkC1IgGk5QIutUQwP2qcnqp1iXcYxH/vCYWK6uKv3gTSpavyRo2vYBPqV6OdctSlaTHw5kvoZF1vKLqcXw+2wJVrkbyfxsgaFXy3tcpoyOFwLF/S7vjTA2Wt/8hXUywQcybio1LsZFV1KOZrxFRwSIbtUBwiXo8s44VI=","ARC-Authentication-Results":"i=1; smtp.subspace.kernel.org;\n dmarc=pass (p=reject dis=none) header.from=bootlin.com;\n spf=pass smtp.mailfrom=bootlin.com;\n dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com\n header.b=NwXAzx19; arc=none smtp.client-ip=217.70.183.199","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1;\n\tt=1731087599;\n\th=from:from:reply-to:subject:subject:date:date:message-id:message-id:\n\t to:to:cc:cc:mime-version:mime-version:content-type:content-type:\n\t content-transfer-encoding:content-transfer-encoding:\n\t in-reply-to:in-reply-to:references:references;\n\tbh=BKjz3h86srqcmGB/4sy6wbmzDtox3/nU1f7+fBVoTIw=;\n\tb=NwXAzx19offAOxoDGjSswAn7NfEKz//W0s4o79RGt3hwiTkahsETewN16ig6ShFREDru8S\n\tC1nLnyJJQsdEWHSAcSwYZ/vG9JdFtIMZzvYHP6H2vw+I8JQoEkYeKO38trMzHuvxo/urni\n\tYKJCffIOyETc+3i2SNGyxveinhfCwkP5f65yqJ20P8p+Dayhfn8gCqGPl0gxfD7nKOYsvq\n\tYVQo2PbUf8hvNZYA4StEpzUdPbzqpg6QwjSq5qKxj4JYCwGl2oeiYWO13htsEyYGv9GtFV\n\tcLIW3F1BL/kLGSaxdF1XVwMB+LnFwqTpJW2SgfvquhmCrhWiYGpEY3TNtP8Glg==","Date":"Fri, 8 Nov 2024 18:39:58 +0100","From":"Herve Codina ","To":"Rob Herring ","Cc":"Greg Kroah-Hartman , \"Rafael J. Wysocki\"\n , Saravana Kannan , Bjorn Helgaas\n , Lizhi Hou ,\n linux-kernel@vger.kernel.org, devicetree@vger.kernel.org,\n linux-pci@vger.kernel.org, Allan Nielsen ,\n Horatiu Vultur , Steen Hegelund\n , Thomas Petazzoni\n ","Subject":"Re: [PATCH v2 5/6] of: Add #address-cells/#size-cells in the\n device-tree root empty node","Message-ID":"<20241108183958.0f136e01@bootlin.com>","In-Reply-To":"\n ","References":"<20241108143600.756224-1-herve.codina@bootlin.com>\n\t<20241108143600.756224-6-herve.codina@bootlin.com>\n\t\n\t<20241108172946.7233825e@bootlin.com>\n\t","Organization":"Bootlin","X-Mailer":"Claws Mail 4.3.0 (GTK 3.24.43; x86_64-redhat-linux-gnu)","Precedence":"bulk","X-Mailing-List":"linux-pci@vger.kernel.org","List-Id":"","List-Subscribe":"","List-Unsubscribe":"","MIME-Version":"1.0","Content-Type":"text/plain; charset=UTF-8","Content-Transfer-Encoding":"8bit","X-GND-Sasl":"herve.codina@bootlin.com"}}]