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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B15ABCEDDA3 for ; Wed, 9 Oct 2024 15:02:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=59YIXIY3yb4p7hqW0ceQbps7VWLwxtiq56+GNU34H6Q=; b=KbvF4Hl5WoEi1lKQJz5haMcdOa QPb7zN/FsCo36rtZ23KjCSKhvpIu3XbE8Zm4GiEdIv8jLnduEaMUst46LYiHgLAHtJiUl5uQC8zN9 MnZbplKjklV/RqB01VZZVDDBoD4R+M2sPry4J+XB+6Xusetn+qyG64rs4+cQufl04CD84fvSVpv/L QL6JtpVgFGiVh4Iro00hBzhagN2DiC52XsOfUDjz/oNGSwWxl2cQnedE4EPuFNvsZL28ZRDPzVmme /F4KhoNOLG0KcNsfj9xWh6eVYUQgqrN4SqNbeJR0w9r5R/2q+eqpyRpV9EGGDlfiN5WcxNlusDGp/ SHUgH/3w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1syYCE-00000009hfT-0NCV; Wed, 09 Oct 2024 15:01:50 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1syYAr-00000009hIX-2UCv for linux-arm-kernel@lists.infradead.org; Wed, 09 Oct 2024 15:00:26 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 0FB065C561B; Wed, 9 Oct 2024 15:00:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4EBD4C4CEC3; Wed, 9 Oct 2024 15:00:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1728486024; bh=D0XqC48xeaaF/Gw7gpqXxx4RqDkm+MnppecvEnCEpig=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=qW6eSMY6s7/qAll04dwOz/7yMIlizS8cRC64xwYK/Sza+B2Y00qXklitkmq0kG2+X 9PR6K2OzUIIY+RbX1D081p3egbuR4lGlmviKUQ8r8Mew2t5FZx1vH+SNdq5kAvy1Wl hcv1Ehk49H2IdeF4kp3bzm3J/pHClJeN7qgv8Vxue900lhJ1ZvXolRgyAm+d/f1XWn IY0mXmkaj/4nL+SwkcyEDFo+QxF+h6U7tHpf6nJtV6hdUa2sI76OkGZImanWKzw+8F spwEkdsZFy0AQz8lj2/UYJ3SGOEWjheJm/6qH6BlxImUtp89uMh07CKC6XoX+HHMxX kyGHUlblJn6Vg== Date: Wed, 9 Oct 2024 17:00:18 +0200 From: Niklas Cassel To: Richard Zhu Cc: robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, shawnguo@kernel.org, l.stach@pengutronix.de, devicetree@vger.kernel.org, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kernel@pengutronix.de, imx@lists.linux.dev Subject: Re: [PATCH v5 1/4] dt-bindings: imx6q-pcie: Add reg-name "dbi2" and "atu" for i.MX8M PCIe Endpoint Message-ID: References: <1723534943-28499-1-git-send-email-hongxing.zhu@nxp.com> <1723534943-28499-2-git-send-email-hongxing.zhu@nxp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1723534943-28499-2-git-send-email-hongxing.zhu@nxp.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241009_080025_746296_73B9857E X-CRM114-Status: GOOD ( 23.01 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list 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=archiver.kernel.org@lists.infradead.org On Tue, Aug 13, 2024 at 03:42:20PM +0800, Richard Zhu wrote: > Add reg-name: "dbi2", "atu" for i.MX8M PCIe Endpoint. > > For i.MX8M PCIe EP, the dbi2 and atu addresses are pre-defined in the > driver. This method is not good. > > In commit b7d67c6130ee ("PCI: imx6: Add iMX95 Endpoint (EP) support"), > Frank suggests to fetch the dbi2 and atu from DT directly. This commit is > preparation to do that for i.MX8M PCIe EP. > > These changes wouldn't break driver function. When "dbi2" and "atu" > properties are present, i.MX PCIe driver would fetch the according base > addresses from DT directly. If only two reg properties are provided, i.MX > PCIe driver would fall back to the old method. > > Signed-off-by: Richard Zhu > Reviewed-by: Frank Li > --- > .../devicetree/bindings/pci/fsl,imx6q-pcie-ep.yaml | 13 +++++++++---- > 1 file changed, 9 insertions(+), 4 deletions(-) > > diff --git a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie-ep.yaml b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie-ep.yaml > index a06f75df8458..84ca12e8b25b 100644 > --- a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie-ep.yaml > +++ b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie-ep.yaml > @@ -65,12 +65,14 @@ allOf: > then: > properties: > reg: > - minItems: 2 > - maxItems: 2 > + minItems: 4 > + maxItems: 4 Now it seems like this patch has already been picked up, but how is this not breaking DT backwards compatibility? You are here increasing minItems, which means that an older DT should now fail to validate using the new schema? I thought that it was only acceptable to add new optional properties after the DT binding has been accepted. What am I missing? If the specific compatible isn't used by any DTS in a released kernel, then I think that the commit log should have clearly stated so, and explained that that is the reason why it is okay to break DT backwards compatibility. Kind regards, Niklas > reg-names: > items: > - const: dbi > - const: addr_space > + - const: dbi2 > + - const: atu > > - if: > properties: > @@ -129,8 +131,11 @@ examples: > > pcie_ep: pcie-ep@33800000 { > compatible = "fsl,imx8mp-pcie-ep"; > - reg = <0x33800000 0x000400000>, <0x18000000 0x08000000>; > - reg-names = "dbi", "addr_space"; > + reg = <0x33800000 0x100000>, > + <0x18000000 0x8000000>, > + <0x33900000 0x100000>, > + <0x33b00000 0x100000>; > + reg-names = "dbi", "addr_space", "dbi2", "atu"; > clocks = <&clk IMX8MP_CLK_HSIO_ROOT>, > <&clk IMX8MP_CLK_HSIO_AXI>, > <&clk IMX8MP_CLK_PCIE_ROOT>; > -- > 2.37.1 >