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 3EE39C02187 for ; Thu, 16 Jan 2025 23:39:50 +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-Transfer-Encoding:Content-Type:MIME-Version:Message-ID:Subject:Cc:To: From:Date:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:References:List-Owner; bh=SiEhUVQJ/TDO2qegrbz7y3eNVFA+s4RZ4K93w4IWgTQ=; b=M9b2UbuFCdaiVSxSXX59soM6Zk +z6BCc3HYPclm2Cg+Sp6J50bQecyv+qHD9q5E3MHp01/6oaZbV8G2uNIuX5Ls+bnTlcTZ6kZgJ1JH IvT64Q9dfTYK97PJeYGZYpoJoB91EkSD0TCLFEBFp3uhqAdvP+69MR0IuObkWebsn6itoZqcP6qly 3CdfmAoka9F8mC03T8VRbXYrhfIok55Lf6jgwr2ymtNz69q5AaGWtx/YOjBOCJLJguQ+Lpg4aoAon aExjXWxT+F36gre8jG/5VZE5LGgh7FUt0lyTIerLQMPcB5p8SYIc4MdJbMwb/pPrallPcn0LLjl7h h8qEnhtg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tYZSZ-0000000GYUl-2eiZ; Thu, 16 Jan 2025 23:39:35 +0000 Received: from nyc.source.kernel.org ([2604:1380:45d1:ec00::3]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tYZIc-0000000GSUs-3KiQ for linux-arm-kernel@lists.infradead.org; Thu, 16 Jan 2025 23:29:20 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id E4BCCA42953; Thu, 16 Jan 2025 23:27:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 66D40C4CED6; Thu, 16 Jan 2025 23:29:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1737070157; bh=dMwwqya1n7mouM0thH4tLEBVCAjWJzbR4JIYV6x+c8k=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=cp95TFTojT43ishZ8WQ4Mwsx3PoDWTZzdjzqZ2MTjofA4fLE8O8H2NZi0DrJToqfR EN9p7UiHkjHhzTnEX/Nnfw+Cdxgdj/equtDNoIPcUVHou6MH8M6OCgjFKCjv+HGZwp IC37Tez0mu7Tp2y+CJAlmCj4QkXPrCmdP4CEtIKKc0En35zUsz+1iuISun5r2YKuNS xmEpPjEcmg9u+Y25j6aMDWqbPqIC5nVLoe7a2/zMsu6AmzR2eZeTWLJ18iDQAeUt8s Qop6AaZZcCjRAJADxFbga5cNKEgIFrVBd0C5IEt1BxzWQFNGeeW+QfYjM6iTVNvmM0 QoTEoKHRcE27A== Date: Thu, 16 Jan 2025 17:29:16 -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: <20250116232916.GA617353@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20250116231358.GA616783@bhelgaas> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250116_152918_963042_D9AC97E1 X-CRM114-Status: GOOD ( 17.71 ) 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 Thu, Jan 16, 2025 at 05:14:00PM -0600, Bjorn Helgaas wrote: > 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? Somehow I expected the patch to skip calling ->cpu_addr_fixup() if the driver had set 'use_parent_dt_ranges'. In fact, I think that's a requirement. Since dw_pcie_prog_outbound_atu() is the only dwc caller, maybe the parent_bus_addr change should go *there* instead of in the callers? Bjorn