Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752161AbaGHVdP (ORCPT ); Tue, 8 Jul 2014 17:33:15 -0400 Received: from mail-pd0-f170.google.com ([209.85.192.170]:58151 "EHLO mail-pd0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751834AbaGHVdM (ORCPT ); Tue, 8 Jul 2014 17:33:12 -0400 Date: Tue, 8 Jul 2014 15:33:05 -0600 From: Bjorn Helgaas To: Liviu Dudau Cc: linux-pci , Catalin Marinas , Will Deacon , Benjamin Herrenschmidt , Arnd Bergmann , linaro-kernel , Tanmay Inamdar , Grant Likely , Sinan Kaya , Jingoo Han , Kukjin Kim , Suravee Suthikulanit , LKML , Device Tree ML , LAKML Subject: Re: [PATCH v8 8/9] pci: Add support for creating a generic host_bridge from device tree Message-ID: <20140708213305.GB4555@google.com> References: <1404240214-9804-1-git-send-email-Liviu.Dudau@arm.com> <1404240214-9804-9-git-send-email-Liviu.Dudau@arm.com> <20140708010103.GD22939@google.com> <20140708102940.GZ6501@e106497-lin.cambridge.arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140708102940.GZ6501@e106497-lin.cambridge.arm.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 08, 2014 at 11:29:40AM +0100, Liviu Dudau wrote: > On Tue, Jul 08, 2014 at 02:01:04AM +0100, Bjorn Helgaas wrote: > > On Tue, Jul 01, 2014 at 07:43:33PM +0100, Liviu Dudau wrote: > > > ... > > > + for_each_of_pci_range(&parser, &range) { > > > + /* Read next ranges element */ > > > + pr_debug("pci_space: 0x%08x pci_addr:0x%016llx cpu_addr:0x%016llx size:0x%016llx\n", > > > + range.pci_space, range.pci_addr, range.cpu_addr, range.size); > > > > If you're not trying to match other printk formats, you could try to match > > the %pR format used elsewhere, e.g., "%#010llx-%#010llx" with > > range.cpu_addr, range.cpu_addr + range.size - 1. > > Yes, not a big fan of the ugly output it generates, but the output matches closely the ranges > definition in the device tree file so it is easy to validate that you are parsing the right > entry. I am happy to change it to shorten the cpu range message. If it already matches other device tree stuff, that's perfect. I'm not familiar with that. > > > +int __weak pcibios_fixup_bridge_ranges(struct list_head *resources) > > > +{ > > > + return 0; > > > +} > > > > I'd wait to add this until there's a platform that needs to implement it. > > Splitting it out will make this patch that much smaller and easier to > > understand. > > I need this as this is the default implementation (i.e. do nothing). Otherwise the > link phase will give errors. I meant that you could remove the default implementation *and* the call of it, since it currently does nothing. > > > diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h > > > index dde3a4a..71e36d0 100644 > > > --- a/include/linux/of_pci.h > > > +++ b/include/linux/of_pci.h > > > @@ -15,6 +15,9 @@ struct device_node *of_pci_find_child_device(struct device_node *parent, > > > int of_pci_get_devfn(struct device_node *np); > > > int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin); > > > int of_pci_parse_bus_range(struct device_node *node, struct resource *res); > > > +struct pci_host_bridge *of_create_pci_host_bridge(struct device *parent, > > > + struct pci_ops *ops, void *host_data); > > > + > > > #else > > > static inline int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq) > > > { > > > @@ -43,6 +46,13 @@ of_pci_parse_bus_range(struct device_node *node, struct resource *res) > > > { > > > return -EINVAL; > > > } > > > + > > > +static inline struct pci_host_bridge * > > > +of_create_pci_host_bridge(struct device *parent, struct pci_ops *ops, > > > + void *host_data) > > > +{ > > > + return NULL; > > > +} > > > #endif > > > > > > #if defined(CONFIG_OF) && defined(CONFIG_PCI_MSI) > > > diff --git a/include/linux/pci.h b/include/linux/pci.h > > > index 7e7b939..556dc5f 100644 > > > --- a/include/linux/pci.h > > > +++ b/include/linux/pci.h > > > @@ -402,6 +402,7 @@ struct pci_host_bridge { > > > struct device dev; > > > struct pci_bus *bus; /* root bus */ > > > int domain_nr; > > > + resource_size_t io_base; /* physical address for the start of I/O area */ > > > > I don't see where this is used yet. > > It's used in pci_host_bridge_of_get_ranges() (earlier in this patch). of_create_pci_host_bridge() fills in bridge->io_base, but I don't see anything that ever *reads* bridge->io_base. > > As far as I know, there's nothing that prevents a host bridge from having > > several I/O port apertures (or several memory-mapped I/O port spaces). > > The pci_register_io_range() will give different offsets for each apperture. > I just need to make sure I don't overwrite io_base when parsing multiple IO > ranges. Let's continue this in the other thread where I'm trying to understand the I/O apertures. Obviously I'm still missing something if you can indeed have multiple I/O apertures per bridge (because then only one of them can start at I/O address 0 on PCI). Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/