Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754160AbaGHKrE (ORCPT ); Tue, 8 Jul 2014 06:47:04 -0400 Received: from service87.mimecast.com ([91.220.42.44]:58714 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752753AbaGHKrB convert rfc822-to-8bit (ORCPT ); Tue, 8 Jul 2014 06:47:01 -0400 Date: Tue, 8 Jul 2014 11:46:56 +0100 From: Liviu Dudau To: Bjorn Helgaas 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 6/9] pci: Introduce a domain number for pci_host_bridge. Message-ID: <20140708104655.GC6501@e106497-lin.cambridge.arm.com> References: <1404240214-9804-1-git-send-email-Liviu.Dudau@arm.com> <1404240214-9804-7-git-send-email-Liviu.Dudau@arm.com> <20140708005954.GC22939@google.com> MIME-Version: 1.0 In-Reply-To: <20140708005954.GC22939@google.com> User-Agent: Mutt/1.5.22 (2013-10-16) X-OriginalArrivalTime: 08 Jul 2014 10:46:56.0844 (UTC) FILETIME=[F04018C0:01CF9A99] X-MC-Unique: 114070811465909401 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 08, 2014 at 01:59:54AM +0100, Bjorn Helgaas wrote: > On Tue, Jul 01, 2014 at 07:43:31PM +0100, Liviu Dudau wrote: > > Make it easier to discover the domain number of a bus by storing > > the number in pci_host_bridge for the root bus. Several architectures > > have their own way of storing this information, so it makes sense > > to try to unify the code. While at this, add a new function that > > creates a root bus in a given domain and make pci_create_root_bus() > > a wrapper around this function. > > "While at this" is always a good clue that maybe something should be > split into a separate patch :) This is a very good example, since it > adds a new interface that deserves its own changelog. Yes, I'm coming to the same conclusion. :) > > > Signed-off-by: Liviu Dudau > > Tested-by: Tanmay Inamdar > > --- > > drivers/pci/probe.c | 41 +++++++++++++++++++++++++++++++++-------- > > include/linux/pci.h | 4 ++++ > > 2 files changed, 37 insertions(+), 8 deletions(-) > > > > diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c > > index 2c92662..abf5e82 100644 > > --- a/drivers/pci/probe.c > > +++ b/drivers/pci/probe.c > > @@ -1748,8 +1748,9 @@ void __weak pcibios_remove_bus(struct pci_bus *bus) > > { > > } > > > > -struct pci_bus *pci_create_root_bus(struct device *parent, int bus, > > - struct pci_ops *ops, void *sysdata, struct list_head *resources) > > +struct pci_bus *pci_create_root_bus_in_domain(struct device *parent, > > + int domain, int bus, struct pci_ops *ops, void *sysdata, > > + struct list_head *resources) > > I don't think we should do it this way; this makes it possible to have a > host bridge where "bridge->domain_nr != pci_domain_nr(bridge->bus)". > > I wonder if it would help to make a weak pci_domain_nr() function that > returns "bridge->domain_nr". Then each arch could individually drop its > pci_domain_nr() definition as it was converted, e.g., something like this: > > - Convert every arch pci_domain_nr() from a #define to a non-inline > function > - Add bridge.domain_nr, initialized from pci_domain_nr() > - Add a weak generic pci_domain_nr() that returns bridge.domain_nr > - Add a way to create a host bridge in a specified domain, so we can > initialize bridge.domain_nr without using pci_domain_nr() > - Convert each arch to use the new creation mechanism and drop its > pci_domain_nr() implementation I will try to propose a patch implementing this. Best regards, Liviu > > > { > > int error; > > struct pci_host_bridge *bridge; > > @@ -1762,27 +1763,31 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, > > > > bridge = pci_alloc_host_bridge(); > > if (!bridge) > > - return NULL; > > + return ERR_PTR(-ENOMEM); > > > > bridge->dev.parent = parent; > > bridge->dev.release = pci_release_host_bridge_dev; > > + bridge->domain_nr = domain; > > > > b = pci_alloc_bus(); > > - if (!b) > > + if (!b) { > > + error = -ENOMEM; > > goto err_out; > > + } > > > > b->sysdata = sysdata; > > b->ops = ops; > > b->number = b->busn_res.start = bus; > > - b2 = pci_find_bus(pci_domain_nr(b), bus); > > + b2 = pci_find_bus(bridge->domain_nr, bus); > > if (b2) { > > /* If we already got to this bus through a different bridge, ignore it */ > > dev_dbg(&b2->dev, "bus already known\n"); > > + error = -EEXIST; > > goto err_bus_out; > > } > > > > bridge->bus = b; > > - dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus); > > + dev_set_name(&bridge->dev, "pci%04x:%02x", bridge->domain_nr, bus); > > error = pcibios_root_bridge_prepare(bridge); > > if (error) > > goto err_out; > > @@ -1801,7 +1806,7 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, > > > > b->dev.class = &pcibus_class; > > b->dev.parent = b->bridge; > > - dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus); > > + dev_set_name(&b->dev, "%04x:%02x", bridge->domain_nr, bus); > > error = device_register(&b->dev); > > if (error) > > goto class_dev_reg_err; > > @@ -1851,7 +1856,27 @@ err_bus_out: > > kfree(b); > > err_out: > > kfree(bridge); > > - return NULL; > > + return ERR_PTR(error); > > +} > > + > > +struct pci_bus *pci_create_root_bus(struct device *parent, int bus, > > + struct pci_ops *ops, void *sysdata, struct list_head *resources) > > +{ > > + int domain_nr; > > + struct pci_bus *b = pci_alloc_bus(); > > + if (!b) > > + return NULL; > > + > > + b->sysdata = sysdata; > > + domain_nr = pci_domain_nr(b); > > + kfree(b); > > + > > + b = pci_create_root_bus_in_domain(parent, domain_nr, bus, > > + ops, sysdata, resources); > > + if (IS_ERR(b)) > > + return NULL; > > + > > + return b; > > } > > > > int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max) > > diff --git a/include/linux/pci.h b/include/linux/pci.h > > index 466bcd1..7e7b939 100644 > > --- a/include/linux/pci.h > > +++ b/include/linux/pci.h > > @@ -401,6 +401,7 @@ struct pci_host_bridge_window { > > struct pci_host_bridge { > > struct device dev; > > struct pci_bus *bus; /* root bus */ > > + int domain_nr; > > struct list_head windows; /* pci_host_bridge_windows */ > > void (*release_fn)(struct pci_host_bridge *); > > void *release_data; > > @@ -769,6 +770,9 @@ struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops, void *sysdata); > > struct pci_bus *pci_create_root_bus(struct device *parent, int bus, > > struct pci_ops *ops, void *sysdata, > > struct list_head *resources); > > +struct pci_bus *pci_create_root_bus_in_domain(struct device *parent, > > + int domain, int bus, struct pci_ops *ops, > > + void *sysdata, struct list_head *resources); > > int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int busmax); > > int pci_bus_update_busn_res_end(struct pci_bus *b, int busmax); > > void pci_bus_release_busn_res(struct pci_bus *b); > > -- > > 2.0.0 > > > -- ==================== | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- ¯\_(ツ)_/¯ -- 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/