From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Simek Subject: Re: pci and pcie device-tree binding - range No cells Date: Mon, 10 Dec 2012 16:05:34 +0100 Message-ID: <50C5FA3E.9030303@monstr.eu> References: <50C5D387.90908@monstr.eu> <50C5F11D.9060006@gmail.com> Reply-To: monstr@monstr.eu Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <50C5F11D.9060006@gmail.com> Sender: linux-pci-owner@vger.kernel.org To: Rob Herring Cc: devicetree-discuss@lists.ozlabs.org, Grant Likely , linux-pci@vger.kernel.org, Rob Herring , linuxppc-dev , Benjamin Herrenschmidt List-Id: devicetree@vger.kernel.org On 12/10/2012 03:26 PM, Rob Herring wrote: > On 12/10/2012 06:20 AM, Michal Simek wrote: >> Hi Grant and others, >> >> I have a question regarding number of cells in ranges property >> for pci and pcie nodes. >> >> Linux pci/pcie powerpc DTSes contain 7 cells (xpedite5370.dts, >> sequoia.dts, etc) >> but also 6 cells format too (mpc832x_mds.dts) >> >> Here is shown 6 cells ranges format and describe >> http://devicetree.org/Device_Tree_Usage#PCI_Host_Bridge >> >> And also in documentation in the linux >> Documentation/devicetree/bindings/pci/83xx-512x-pci.txt >> >> Both format uses: >> #size-cells = <2>; >> #address-cells = <3>; >> >> What is valid format? > > Both. 7 cells are valid when the host (parent) bus is 64-bit and 6 cells > are valid when the host bus is 32-bit. The ranges property is < address> >. The parent address #address-cells is > taken from the parent node. Ok. Got it. Here is what we use on zynq and microblaze - both 32bit which should be fine. ps7_axi_interconnect_0: axi@0 { #address-cells = <1>; #size-cells = <1>; axi_pcie_0: axi-pcie@50000000 { #address-cells = <3>; #size-cells = <2>; compatible = "xlnx,axi-pcie-1.05.a"; ranges = < 0x02000000 0 0x60000000 0x60000000 0 0x10000000 >; ... } } What I am wondering is pci_process_bridge_OF_ranges() at arch/powerpc/kernel/pci-common.c where there are used some hardcoded values which should be probably loaded from device-tree. For example: 683 int np = pna + 5; ... 702 pci_addr = of_read_number(ranges + 1, 2); 703 cpu_addr = of_translate_address(dev, ranges + 3); 704 size = of_read_number(ranges + pna + 3, 2); Unfortunately we have copied it to microblaze. Thanks, Michal -- Michal Simek, Ing. (M.Eng) w: www.monstr.eu p: +42-0-721842854 Maintainer of Linux kernel 2.6 Microblaze Linux - http://www.monstr.eu/fdt/ Microblaze U-BOOT custodian