From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F050D23F263; Thu, 16 Jan 2025 23:14:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737069241; cv=none; b=NUT+DN00JrM1HcmBnw70ydYIFDLEP/FaJU4d+zBd7S9OAmY9immTvfhUs6hnoq/y4kOhz1/0bsIT0ZNIuW8Ew07wspH2bDZNNQsQ6ZHM2Q31Ocaa/55JupwdDZyTH8DHcD83VhJmJx4P3KbpTIKp0uehlKFw3n1V0t3bWhZMUXU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737069241; c=relaxed/simple; bh=M8EIC7pg0Wzyi0pL5SQg5Thdf/ff+JRgC1JyfSUFHds=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=tTS/2Psjgh2LOlJ/mvRNhoNrGksiN3PaU0g3Z00ztTxp4gbI7oIO24pCNhEn3Ffg6eHPVXjWvQz3SKCcDDDBBJIl/YG2YUmhEAiQJUEo8JhXeLCbxuB3LePKMOMpry5850Bxan655AByt0SiRvacg9p0/Sr2hpZHWksUUVt3VAA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nlBbMT1I; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="nlBbMT1I" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 36126C4CED6; Thu, 16 Jan 2025 23:14:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1737069240; bh=M8EIC7pg0Wzyi0pL5SQg5Thdf/ff+JRgC1JyfSUFHds=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=nlBbMT1Ijt2VrpfQTtch051uILthsjl//w99RARSxLK3YBLv5BvNBb2BYRXTH1TBI ttnTjtts6lruViF6D4uMZRH3ba6GNopequdvdcWqn+zygPVTCOOmAlSG248KrGiQrF w4EJcEVl1RePa9HP6TLcgwey3zjOIo6b+o4dzycz7dNTk8QDAqxmqxqR5So3XldrS6 pyIwzVNl5QN2HN9sviZmUfobLrsUD0PMB/SkNu6VcpJRP+BxRowy/sfuxGJxw6w6pK Q9UmlxFxuR+JqS2Sjn+Qab6IWO+WGGCFI01bfthuPDz4G/6gqjb4N9uMNrAf5Qplae foqxXHSkyCzKQ== Date: Thu, 16 Jan 2025 17:13:58 -0600 From: Bjorn Helgaas To: Frank Li Cc: Rob Herring , Saravana Kannan , Jingoo Han , Manivannan Sadhasivam , Lorenzo Pieralisi , Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= , Bjorn Helgaas , Richard Zhu , Lucas Stach , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, imx@lists.linux.dev Subject: Re: [PATCH v8 2/7] PCI: dwc: Use devicetree 'ranges' property to get rid of cpu_addr_fixup() callback Message-ID: <20250116231358.GA616783@bhelgaas> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20241119-pci_fixup_addr-v8-2-c4bfa5193288@nxp.com> On Tue, Nov 19, 2024 at 02:44:20PM -0500, Frank Li wrote: > parent_bus_addr in struct of_range can indicate address information just > ahead of PCIe controller. Most system's bus fabric use 1:1 map between > input and output address. but some hardware like i.MX8QXP doesn't use 1:1 > map. See below diagram: > > ┌─────────┐ ┌────────────┐ > ┌─────┐ │ │ IA: 0x8ff8_0000 │ │ > │ CPU ├───►│ ┌────►├─────────────────┐ │ PCI │ > └─────┘ │ │ │ IA: 0x8ff0_0000 │ │ │ > CPU Addr │ │ ┌─►├─────────────┐ │ │ Controller │ > 0x7ff8_0000─┼───┘ │ │ │ │ │ │ > │ │ │ │ │ │ │ PCI Addr > 0x7ff0_0000─┼──────┘ │ │ └──► IOSpace ─┼────────────► > │ │ │ │ │ 0 > 0x7000_0000─┼────────►├─────────┐ │ │ │ > └─────────┘ │ └──────► CfgSpace ─┼────────────► > BUS Fabric │ │ │ 0 > │ │ │ > └──────────► MemSpace ─┼────────────► > IA: 0x8000_0000 │ │ 0x8000_0000 > └────────────┘ > > bus@5f000000 { > compatible = "simple-bus"; > #address-cells = <1>; > #size-cells = <1>; > ranges = <0x80000000 0x0 0x70000000 0x10000000>; > > pcie@5f010000 { > compatible = "fsl,imx8q-pcie"; > reg = <0x5f010000 0x10000>, <0x8ff00000 0x80000>; > reg-names = "dbi", "config"; > #address-cells = <3>; > #size-cells = <2>; > device_type = "pci"; > bus-range = <0x00 0xff>; > ranges = <0x81000000 0 0x00000000 0x8ff80000 0 0x00010000>, > <0x82000000 0 0x80000000 0x80000000 0 0x0ff00000>; > ... > }; > }; > > Term internal address (IA) here means the address just before PCIe > controller. After ATU use this IA instead CPU address, cpu_addr_fixup() can > be removed. > @@ -730,9 +779,15 @@ static int dw_pcie_iatu_setup(struct dw_pcie_rp *pp) > > atu.index = i; > atu.type = PCIE_ATU_TYPE_MEM; > - atu.cpu_addr = entry->res->start; > + parent_bus_addr = entry->res->start; > atu.pci_addr = entry->res->start - entry->offset; > > + ret = dw_pcie_get_parent_addr(pci, entry->res->start, &parent_bus_addr); > + if (ret) > + return ret; > + > + atu.cpu_addr = parent_bus_addr; Here you set atu.cpu_addr to the intermediate bus address instead of the CPU physical address before calling dw_pcie_prog_outbound_atu(). But what about other callers of dw_pcie_prog_outbound_atu()? Don't all of them need to use the intermediate bus address? Maybe struct dw_pcie_ob_atu_cfg.cpu_addr should be renamed since it is not necessarily a CPU physical address? > + if (pci->ops && pci->ops->cpu_addr_fixup) { > + /* > + * If the parent 'ranges' property in DT correctly describes > + * the address translation, cpu_addr_fixup() callback is not > + * needed. > + */ > + dev_warn_once(pci->dev, "cpu_addr_fixup() usage detected. Please fix DT!\n"); > + } I kinda wish this warning were in a separate patch because it will be a little cleaner if we ever want to revert or remove the warning.