From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 83110C433E1 for ; Mon, 17 Aug 2020 17:48:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 65A2720716 for ; Mon, 17 Aug 2020 17:48:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597686509; bh=gOa0eYxDEsJl2GQzrDLlhSJ5bJ/ZSXUtDonvSlh0ISI=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=ZW5qArHT+zYCoU8Ojaf8bv+yIBwUTLmUrUJWcNORgCla8mY4ALLN+VHntOvGjm+5m 1mOBClOEsyJNKADVGZCrfWSmVowkXzQJjdNeUNdP7heN9TiSA1YH4Zmrd0nXFgl0A+ x/Pue2aAZIGfcjJOzAAOXRYF2hu2+2pb5UaiBZa8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390098AbgHQRs1 (ORCPT ); Mon, 17 Aug 2020 13:48:27 -0400 Received: from mail.kernel.org ([198.145.29.99]:46942 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388746AbgHQQNM (ORCPT ); Mon, 17 Aug 2020 12:13:12 -0400 Received: from mail-ot1-f43.google.com (mail-ot1-f43.google.com [209.85.210.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E72C820882; Mon, 17 Aug 2020 16:13:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597680791; bh=gOa0eYxDEsJl2GQzrDLlhSJ5bJ/ZSXUtDonvSlh0ISI=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=vLRATeCcDCX/WCszaMIH4H6QE5Q8qaxo+6lOPhJY3rU/qC3/KnPHOgpGDtINee7Gq VcWIayKF3Q5vcKl+04xcwMH7/dbSBKTxAP7wJHZxqdCIaZTaY9H7oqkp8AkQMziwc8 C466cFsSL7D9DSNpN4oisiuWqbgpp5MlAwUUJYj4= Received: by mail-ot1-f43.google.com with SMTP id h22so13818866otq.11; Mon, 17 Aug 2020 09:13:10 -0700 (PDT) X-Gm-Message-State: AOAM531NhY7Wt0pAoz/CGBobj3yGVukH2RMWCgIJe/MsLh2Zs4iCYRgU XEGus4Y64M0JWEZhp8O1r0TWjGYLEjztDfWyJw== X-Google-Smtp-Source: ABdhPJyXcxsLxb+WyZgDqUvX+ZXB5O5RvpOgmleI0+UY8O6F4IJdy3paAveojUJFPRMuv9DQhsNQTGig0iW3qRkFcQI= X-Received: by 2002:a9d:7f84:: with SMTP id t4mr11916864otp.192.1597680790121; Mon, 17 Aug 2020 09:13:10 -0700 (PDT) MIME-Version: 1.0 References: <20200815125112.462652-2-maz@kernel.org> <20200815232228.GA1325245@bjorn-Precision-5520> <87pn7qnabq.wl-maz@kernel.org> In-Reply-To: <87pn7qnabq.wl-maz@kernel.org> From: Rob Herring Date: Mon, 17 Aug 2020 10:12:58 -0600 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 1/2] PCI: rockchip: Work around missing device_type property in DT To: Marc Zyngier Cc: Bjorn Helgaas , PCI , "open list:ARM/Rockchip SoC..." , "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" , "linux-kernel@vger.kernel.org" , Lorenzo Pieralisi , Heiko Stuebner , Shawn Lin , Bjorn Helgaas , Android Kernel Team Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Aug 16, 2020 at 4:40 AM Marc Zyngier wrote: > > On Sun, 16 Aug 2020 00:22:28 +0100, > Bjorn Helgaas wrote: > > > > On Sat, Aug 15, 2020 at 01:51:11PM +0100, Marc Zyngier wrote: > > > Recent changes to the DT PCI bus parsing made it mandatory for > > > device tree nodes describing a PCI controller to have the > > > 'device_type = "pci"' property for the node to be matched. > > > > > > Although this follows the letter of the specification, it > > > breaks existing device-trees that have been working fine > > > for years. Rockchip rk3399-based systems are a prime example > > > of such collateral damage, and have stopped discovering their > > > PCI bus. > > > > > > In order to paper over the blunder, let's add a workaround > > > to the pcie-rockchip driver, adding the missing property when > > > none is found at boot time. A warning will hopefully nudge the > > > user into updating their DT to a fixed version if they can, but > > > the insentive is obviously pretty small. > > > > s/insentive/incentive/ (Lorenzo or I can fix this up) > > > > > Fixes: 2f96593ecc37 ("of_address: Add bus type match for pci ranges parser") > > > Suggested-by: Roh Herring > > > > s/Roh/Rob/ (similarly) > > Clearly not my day when it comes to proofreading commit messages. > Thanks for pointing this out, and in advance for fixing it up. > > > > > > Signed-off-by: Marc Zyngier > > > > This looks like a candidate for v5.9, since 2f96593ecc37 was merged > > during the v5.9 merge window, right? > > Absolutely. > > > I wonder how many other DTs are similarly broken? Maybe Rob's DT > > checker has already looked? > > I've just managed to run the checker, which comes up with all kinds of > goodies. Apart from the above, it also spots the following: > > - arch/arm64/boot/dts/mediatek/mt7622.dtsi: Has a device_type property > in its main PCIe node, but not in the child nodes. It isn't obvious > to me whether that's a violation or not (the spec doesn't say > whether the property should be set on a per-port basis). Rob? The rule is bridge nodes should have 'device_type = "pci"'. But what's needed to fix these cases is setting device_type where we are parsing ranges or dma-ranges which we're not doing on the child ndes. Otherwise, I don't think it matters in this case unless you have child (grandchild here) nodes for PCI devices. If you did have child nodes, the address translation was already broken before this change. > - arch/arm64/boot/dts/qcom/msm8996.dtsi: Only one out of the three > PCIe nodes has the device_type property, probably broken similarly > to rk3399. The only upstream board is DB820c, so probably not as wide an impact... There are also 92 (lots of duplicates due to multiple boards) more cases in arch/arm/. A log is here[1]. > I could move the workaround to drivers/pci/of.c, and have it called > from the individual drivers. I don't have the HW to test those though. > > Thoughts? I think we should go with my other suggestion of looking at the node name. Looks like just checking 'pcie' is enough. We can skip 'pci' as I don't see any cases. Rob [1] https://gitlab.com/robherring/linux-dt-bindings/-/jobs/688752562 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4986FC433E1 for ; Mon, 17 Aug 2020 16:13:26 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0D7D020657 for ; Mon, 17 Aug 2020 16:13:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="R476DeeD"; 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Mon, 17 Aug 2020 09:13:10 -0700 (PDT) X-Gm-Message-State: AOAM532Ut9eAVWvhtxrpbAQ6l894yofwrEB88AOjrUcO2GQFhwHNlhpu IE/g2NPvXHXnq4Zh0r8Avmt/t5eu17yacEVxPA== X-Google-Smtp-Source: ABdhPJyXcxsLxb+WyZgDqUvX+ZXB5O5RvpOgmleI0+UY8O6F4IJdy3paAveojUJFPRMuv9DQhsNQTGig0iW3qRkFcQI= X-Received: by 2002:a9d:7f84:: with SMTP id t4mr11916864otp.192.1597680790121; Mon, 17 Aug 2020 09:13:10 -0700 (PDT) MIME-Version: 1.0 References: <20200815125112.462652-2-maz@kernel.org> <20200815232228.GA1325245@bjorn-Precision-5520> <87pn7qnabq.wl-maz@kernel.org> In-Reply-To: <87pn7qnabq.wl-maz@kernel.org> From: Rob Herring Date: Mon, 17 Aug 2020 10:12:58 -0600 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 1/2] PCI: rockchip: Work around missing device_type property in DT To: Marc Zyngier X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200817_121312_886821_34E84CC5 X-CRM114-Status: GOOD ( 34.28 ) X-BeenThere: linux-rockchip@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Upstream kernel work for Rockchip platforms List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Lorenzo Pieralisi , Heiko Stuebner , PCI , Shawn Lin , "linux-kernel@vger.kernel.org" , "open list:ARM/Rockchip SoC..." , Bjorn Helgaas , Bjorn Helgaas , Android Kernel Team , "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+linux-rockchip=archiver.kernel.org@lists.infradead.org On Sun, Aug 16, 2020 at 4:40 AM Marc Zyngier wrote: > > On Sun, 16 Aug 2020 00:22:28 +0100, > Bjorn Helgaas wrote: > > > > On Sat, Aug 15, 2020 at 01:51:11PM +0100, Marc Zyngier wrote: > > > Recent changes to the DT PCI bus parsing made it mandatory for > > > device tree nodes describing a PCI controller to have the > > > 'device_type = "pci"' property for the node to be matched. > > > > > > Although this follows the letter of the specification, it > > > breaks existing device-trees that have been working fine > > > for years. Rockchip rk3399-based systems are a prime example > > > of such collateral damage, and have stopped discovering their > > > PCI bus. > > > > > > In order to paper over the blunder, let's add a workaround > > > to the pcie-rockchip driver, adding the missing property when > > > none is found at boot time. A warning will hopefully nudge the > > > user into updating their DT to a fixed version if they can, but > > > the insentive is obviously pretty small. > > > > s/insentive/incentive/ (Lorenzo or I can fix this up) > > > > > Fixes: 2f96593ecc37 ("of_address: Add bus type match for pci ranges parser") > > > Suggested-by: Roh Herring > > > > s/Roh/Rob/ (similarly) > > Clearly not my day when it comes to proofreading commit messages. > Thanks for pointing this out, and in advance for fixing it up. > > > > > > Signed-off-by: Marc Zyngier > > > > This looks like a candidate for v5.9, since 2f96593ecc37 was merged > > during the v5.9 merge window, right? > > Absolutely. > > > I wonder how many other DTs are similarly broken? Maybe Rob's DT > > checker has already looked? > > I've just managed to run the checker, which comes up with all kinds of > goodies. Apart from the above, it also spots the following: > > - arch/arm64/boot/dts/mediatek/mt7622.dtsi: Has a device_type property > in its main PCIe node, but not in the child nodes. It isn't obvious > to me whether that's a violation or not (the spec doesn't say > whether the property should be set on a per-port basis). Rob? The rule is bridge nodes should have 'device_type = "pci"'. But what's needed to fix these cases is setting device_type where we are parsing ranges or dma-ranges which we're not doing on the child ndes. Otherwise, I don't think it matters in this case unless you have child (grandchild here) nodes for PCI devices. If you did have child nodes, the address translation was already broken before this change. > - arch/arm64/boot/dts/qcom/msm8996.dtsi: Only one out of the three > PCIe nodes has the device_type property, probably broken similarly > to rk3399. The only upstream board is DB820c, so probably not as wide an impact... There are also 92 (lots of duplicates due to multiple boards) more cases in arch/arm/. A log is here[1]. > I could move the workaround to drivers/pci/of.c, and have it called > from the individual drivers. I don't have the HW to test those though. > > Thoughts? I think we should go with my other suggestion of looking at the node name. Looks like just checking 'pcie' is enough. We can skip 'pci' as I don't see any cases. Rob [1] https://gitlab.com/robherring/linux-dt-bindings/-/jobs/688752562 _______________________________________________ Linux-rockchip mailing list Linux-rockchip@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-rockchip From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5F2DEC433E1 for ; Mon, 17 Aug 2020 16:14:51 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1EE8820760 for ; 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a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597680791; bh=gOa0eYxDEsJl2GQzrDLlhSJ5bJ/ZSXUtDonvSlh0ISI=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=vLRATeCcDCX/WCszaMIH4H6QE5Q8qaxo+6lOPhJY3rU/qC3/KnPHOgpGDtINee7Gq VcWIayKF3Q5vcKl+04xcwMH7/dbSBKTxAP7wJHZxqdCIaZTaY9H7oqkp8AkQMziwc8 C466cFsSL7D9DSNpN4oisiuWqbgpp5MlAwUUJYj4= Received: by mail-ot1-f53.google.com with SMTP id v6so13800908ota.13; Mon, 17 Aug 2020 09:13:10 -0700 (PDT) X-Gm-Message-State: AOAM532Ut9eAVWvhtxrpbAQ6l894yofwrEB88AOjrUcO2GQFhwHNlhpu IE/g2NPvXHXnq4Zh0r8Avmt/t5eu17yacEVxPA== X-Google-Smtp-Source: ABdhPJyXcxsLxb+WyZgDqUvX+ZXB5O5RvpOgmleI0+UY8O6F4IJdy3paAveojUJFPRMuv9DQhsNQTGig0iW3qRkFcQI= X-Received: by 2002:a9d:7f84:: with SMTP id t4mr11916864otp.192.1597680790121; Mon, 17 Aug 2020 09:13:10 -0700 (PDT) MIME-Version: 1.0 References: <20200815125112.462652-2-maz@kernel.org> <20200815232228.GA1325245@bjorn-Precision-5520> <87pn7qnabq.wl-maz@kernel.org> In-Reply-To: <87pn7qnabq.wl-maz@kernel.org> From: Rob Herring Date: Mon, 17 Aug 2020 10:12:58 -0600 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 1/2] PCI: rockchip: Work around missing device_type property in DT To: Marc Zyngier X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200817_121312_886821_34E84CC5 X-CRM114-Status: GOOD ( 34.28 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Lorenzo Pieralisi , Heiko Stuebner , PCI , Shawn Lin , "linux-kernel@vger.kernel.org" , "open list:ARM/Rockchip SoC..." , Bjorn Helgaas , Bjorn Helgaas , Android Kernel Team , "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sun, Aug 16, 2020 at 4:40 AM Marc Zyngier wrote: > > On Sun, 16 Aug 2020 00:22:28 +0100, > Bjorn Helgaas wrote: > > > > On Sat, Aug 15, 2020 at 01:51:11PM +0100, Marc Zyngier wrote: > > > Recent changes to the DT PCI bus parsing made it mandatory for > > > device tree nodes describing a PCI controller to have the > > > 'device_type = "pci"' property for the node to be matched. > > > > > > Although this follows the letter of the specification, it > > > breaks existing device-trees that have been working fine > > > for years. Rockchip rk3399-based systems are a prime example > > > of such collateral damage, and have stopped discovering their > > > PCI bus. > > > > > > In order to paper over the blunder, let's add a workaround > > > to the pcie-rockchip driver, adding the missing property when > > > none is found at boot time. A warning will hopefully nudge the > > > user into updating their DT to a fixed version if they can, but > > > the insentive is obviously pretty small. > > > > s/insentive/incentive/ (Lorenzo or I can fix this up) > > > > > Fixes: 2f96593ecc37 ("of_address: Add bus type match for pci ranges parser") > > > Suggested-by: Roh Herring > > > > s/Roh/Rob/ (similarly) > > Clearly not my day when it comes to proofreading commit messages. > Thanks for pointing this out, and in advance for fixing it up. > > > > > > Signed-off-by: Marc Zyngier > > > > This looks like a candidate for v5.9, since 2f96593ecc37 was merged > > during the v5.9 merge window, right? > > Absolutely. > > > I wonder how many other DTs are similarly broken? Maybe Rob's DT > > checker has already looked? > > I've just managed to run the checker, which comes up with all kinds of > goodies. Apart from the above, it also spots the following: > > - arch/arm64/boot/dts/mediatek/mt7622.dtsi: Has a device_type property > in its main PCIe node, but not in the child nodes. It isn't obvious > to me whether that's a violation or not (the spec doesn't say > whether the property should be set on a per-port basis). Rob? The rule is bridge nodes should have 'device_type = "pci"'. But what's needed to fix these cases is setting device_type where we are parsing ranges or dma-ranges which we're not doing on the child ndes. Otherwise, I don't think it matters in this case unless you have child (grandchild here) nodes for PCI devices. If you did have child nodes, the address translation was already broken before this change. > - arch/arm64/boot/dts/qcom/msm8996.dtsi: Only one out of the three > PCIe nodes has the device_type property, probably broken similarly > to rk3399. The only upstream board is DB820c, so probably not as wide an impact... There are also 92 (lots of duplicates due to multiple boards) more cases in arch/arm/. A log is here[1]. > I could move the workaround to drivers/pci/of.c, and have it called > from the individual drivers. I don't have the HW to test those though. > > Thoughts? I think we should go with my other suggestion of looking at the node name. Looks like just checking 'pcie' is enough. We can skip 'pci' as I don't see any cases. Rob [1] https://gitlab.com/robherring/linux-dt-bindings/-/jobs/688752562 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel