Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758146AbaKUJxU (ORCPT ); Fri, 21 Nov 2014 04:53:20 -0500 Received: from service87.mimecast.com ([91.220.42.44]:52724 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755233AbaKUJxR convert rfc822-to-8bit (ORCPT ); Fri, 21 Nov 2014 04:53:17 -0500 Date: Fri, 21 Nov 2014 09:53:12 +0000 From: Liviu Dudau To: Yijing Wang Cc: Bjorn Helgaas , "linux-pci@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "huxinwei@huawei.com" , Wuyun , "linux-arm-kernel@lists.infradead.org" , Russell King , "x86@kernel.org" , Thomas Gleixner , Benjamin Herrenschmidt , "linuxppc-dev@lists.ozlabs.org" , Tony Luck , "linux-ia64@vger.kernel.org" , Thierry Reding , Liviu Dudau , "suravee.suthikulpanit@amd.com" Subject: Re: [RFC PATCH 07/16] PCI: Separate pci_host_bridge creation out of pci_create_root_bus() Message-ID: <20141121095311.GG17214@e106497-lin.cambridge.arm.com> References: <1416219710-26088-1-git-send-email-wangyijing@huawei.com> <1416219710-26088-8-git-send-email-wangyijing@huawei.com> <20141118153020.GL12037@e106497-lin.cambridge.arm.com> <546BF59C.8060203@huawei.com> <20141119163726.GW12037@e106497-lin.cambridge.arm.com> <546D5647.8030401@huawei.com> <20141120094741.GA17214@e106497-lin.cambridge.arm.com> <546EA90D.3040304@huawei.com> MIME-Version: 1.0 In-Reply-To: <546EA90D.3040304@huawei.com> User-Agent: Mutt/1.5.22 (2013-10-16) X-OriginalArrivalTime: 21 Nov 2014 09:53:13.0181 (UTC) FILETIME=[F6FA28D0:01D00570] X-MC-Unique: 114112109531304001 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 Fri, Nov 21, 2014 at 02:53:01AM +0000, Yijing Wang wrote: > >>> pci_create_host_bridge() can get pci_host_bridge ops while pci_create_root_bus() gets > >>> the bus ops. For find out the MSI controller, the domain number and any other HB > >>> specific stuff, you use the HB ops. For config R/W acceses you use bus ops. > >>> > >> > >> I want to unexport pci_create_root_bus() if we have pci_create_host_bridge(). > > > > That's fine, but the function signature doesn't change, right? And I think we should keep > > pci_scan_root_bus() with the current signature as well (except change sysdata into a > > struct pci_host_bridge *). We create the host bridge in one step, stuff it with all the > > data that we need for scanning the root and associated busses, and then call pci_scan_root_bus(). > > pci_host_bridge has the ops from pci_create_host_bridge() and the root bus from pci_scan_root_bus(). > > Liviu, could you have some draft patches about replace sysdata with pci_host_bridge, so we could > discuss the details base it. :) Sure, I'll try to send something soon. Best regards, Liviu > > > > > Hope this makes sense. > > > >> > >> > >>>>>> -struct pci_bus *pci_create_root_bus(struct device *parent, u32 db, > >>>>>> - struct pci_ops *ops, void *sysdata, struct list_head *resources) > >>>>>> +struct pci_bus *__pci_create_root_bus(struct pci_host_bridge *bridge) > >>>>>> { > >>>>>> int error; > >>>>>> - struct pci_host_bridge *bridge; > >>>>>> struct pci_bus *b, *b2; > >>>>>> - struct pci_host_bridge_window *window, *n; > >>>>>> + struct pci_host_bridge_window *window; > >>>>>> struct resource *res; > >>>>>> resource_size_t offset; > >>>>>> char bus_addr[64]; > >>>>>> char *fmt; > >>>>>> - u8 bus = PCI_BUSNUM(db); > >>>>>> + struct device *parent = bridge->dev.parent; > >>>>>> > >>>>>> b = pci_alloc_bus(NULL); > >>>>>> if (!b) > >>>>>> return NULL; > >>>>>> > >>>>>> - b->sysdata = sysdata; > >>>>>> - b->ops = ops; > >>>>>> - b->number = b->busn_res.start = bus; > >>>>>> + b->sysdata = bridge->sysdata; > >>>>> > >>>>> I think bridge should be the b->sysdata here. > >>>> > >>>> ? what's the meaning? > >>> > >>> Currently, bus->sysdata holds a pointer to the arch/driver host bridge structure, as passed > >>> in pci_create_root_bus(). If you agree with my idea of wrapping the host bridge driver > >>> structure around the pci_host_bridge, then we will always have a way of retrieving that > >>> information; but for backwards compatibility we could set bus->sysdata to be the bridge. > >>> Then existing macros that convert sysdata to pci_controller can be reused after being > >>> updated. > >> > >> I think wrapping the host bridge driver structure around the pci_host_bridge could help > >> us to find the private pci_controller, but in this case, pci_host_bridge is not a pointer > >> so we put all pci_host_bridge init stuff in host drivers ? > > > > Of course we put pci_host_bridge init *calls* in the host drivers because we need to do host > > driver specific initialisation there anyway. > > > >> And if we still use arch spec > >> macros convert ssydata to pci_controller, so what's the greatest advantage ? > > > > Agree, the macro is not useful unless we have a common pci_controller structure. Sorry about > > the noise. > > > >> > >> If we move domain and msi_chip out of sysdata, what's other things in sysdata still need us > >> to convert in PCI core ? > > > > I've never said we need to keep sysdata. From my discussion with Bjorn a year ago the idea was > > to put the sysdata members into pci_host_bridge structure and remove sysdata member from pci_bus. > > pci_scan_root_bus() can still get a parameter called sysdata if we want, but it will be a > > struct pci_host_bridge * type. > > Fine. > > > > > Best regards, > > Liviu > > > >> > >> > >> > >>> > >>> Best regards, > >>> Liviu > >>> > >>>> > >>>>> > >>>>>> + b->ops = bridge->ops; > >>>>> > >>>>> See comment above why I don't think this is necessary. > >>>>> > >>>>>> + b->number = b->busn_res.start = bridge->busnum; > >>>>>> pci_bus_assign_domain_nr(b, parent); > >>>>>> - b2 = pci_find_bus(pci_domain_nr(b), bus); > >>>>>> + bridge->domain = pci_domain_nr(b); > >>>>> > >>>>> Do you really want to overwrite the bridge's domain with the one from a bus that > >>>>> could possibly be rejected a couple of lines further down? > >>>>> > >>>>> As an asside: if we are doing the split of pci_host_bridge from root bus creation > >>>>> it is worth in my opinion to move the domain setup in pci_create_host_bridge() > >>>>> and stop fiddling with it here. > >>>> > >>>> > >>>> Hi Liviu, these lines just temporary, I will remove it after all host drivers > >>>> save its domain in pci_host_bridge. > >>>> > >>>> > >>>>> > >>>>> Otherwise it looks to me like you are heading in the right direction. > >>>> > >>>> Thanks! > >>>> Yijing. > >>>> > >>>>> > >>>>> Best regards, > >>>>> Liviu > >>>>> > >>>>>> + b2 = pci_find_bus(pci_domain_nr(b), bridge->busnum); > >>>>>> if (b2) { > >>>>>> /* If we already got to this bus through a different bridge, ignore it */ > >>>>>> dev_dbg(&b2->dev, "bus already known\n"); > >>>>>> goto err_out; > >>>>>> } > >>>>>> > >>>>>> - bridge = pci_alloc_host_bridge(b); > >>>>>> - if (!bridge) > >>>>>> - goto err_out; > >>>>>> - > >>>>>> - bridge->dev.parent = parent; > >>>>>> - bridge->dev.release = pci_release_host_bridge_dev; > >>>>>> - dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus); > >>>>>> - error = pcibios_root_bridge_prepare(bridge); > >>>>>> - if (error) { > >>>>>> - kfree(bridge); > >>>>>> - goto err_out; > >>>>>> - } > >>>>>> - > >>>>>> - error = device_register(&bridge->dev); > >>>>>> - if (error) { > >>>>>> - put_device(&bridge->dev); > >>>>>> - goto err_out; > >>>>>> - } > >>>>>> b->bridge = get_device(&bridge->dev); > >>>>>> device_enable_async_suspend(b->bridge); > >>>>>> pci_set_bus_of_node(b); > >>>>>> @@ -1950,7 +1899,7 @@ struct pci_bus *pci_create_root_bus(struct device *parent, u32 db, > >>>>>> > >>>>>> 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", pci_domain_nr(b), b->number); > >>>>>> error = device_register(&b->dev); > >>>>>> if (error) > >>>>>> goto class_dev_reg_err; > >>>>>> @@ -1966,12 +1915,11 @@ struct pci_bus *pci_create_root_bus(struct device *parent, u32 db, > >>>>>> printk(KERN_INFO "PCI host bridge to bus %s\n", dev_name(&b->dev)); > >>>>>> > >>>>>> /* Add initial resources to the bus */ > >>>>>> - list_for_each_entry_safe(window, n, resources, list) { > >>>>>> - list_move_tail(&window->list, &bridge->windows); > >>>>>> + list_for_each_entry(window, &bridge->windows, list) { > >>>>>> res = window->res; > >>>>>> offset = window->offset; > >>>>>> if (res->flags & IORESOURCE_BUS) > >>>>>> - pci_bus_insert_busn_res(b, bus, res->end); > >>>>>> + pci_bus_insert_busn_res(b, b->number, res->end); > >>>>>> else > >>>>>> pci_bus_add_resource(b, res, 0); > >>>>>> if (offset) { > >>>>>> @@ -2001,6 +1949,25 @@ err_out: > >>>>>> return NULL; > >>>>>> } > >>>>>> > >>>>>> +struct pci_bus *pci_create_root_bus(struct device *parent, u32 bus, > >>>>>> + struct pci_ops *ops, void *sysdata, struct list_head *resources) > >>>>>> +{ > >>>>>> + struct pci_host_bridge *host; > >>>>>> + > >>>>>> + host = pci_create_host_bridge(parent, bus, ops, > >>>>>> + sysdata ,resources); > >>>>>> + if (!host) > >>>>>> + return NULL; > >>>>>> + > >>>>>> + host->bus = __pci_create_root_bus(host); > >>>>>> + if (!host->bus) { > >>>>>> + pci_free_host_bridge(host); > >>>>>> + return NULL; > >>>>>> + } > >>>>>> + > >>>>>> + return host->bus; > >>>>>> +} > >>>>>> + > >>>>>> int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max) > >>>>>> { > >>>>>> struct resource *res = &b->busn_res; > >>>>>> @@ -2069,40 +2036,37 @@ struct pci_bus *pci_scan_root_bus(struct device *parent, u32 db, > >>>>>> { > >>>>>> struct pci_host_bridge_window *window; > >>>>>> bool found = false; > >>>>>> - struct pci_bus *b; > >>>>>> - LIST_HEAD(default_res); > >>>>>> + struct pci_host_bridge *host; > >>>>>> int max; > >>>>>> > >>>>>> - if (!resources) { > >>>>>> - pci_add_resource(&default_res, &ioport_resource); > >>>>>> - pci_add_resource(&default_res, &iomem_resource); > >>>>>> - pci_add_resource(&default_res, &busn_resource); > >>>>>> - } else { > >>>>>> - list_for_each_entry(window, resources, list) > >>>>>> - if (window->res->flags & IORESOURCE_BUS) { > >>>>>> - found = true; > >>>>>> - break; > >>>>>> - } > >>>>>> - } > >>>>>> + host = pci_create_host_bridge(parent, db, ops, sysdata, resources); > >>>>>> + if (!host) > >>>>>> + return NULL; > >>>>>> > >>>>>> - b = pci_create_root_bus(parent, db, ops, sysdata, > >>>>>> - resources ? resources : &default_res); > >>>>>> - if (!b) > >>>>>> + list_for_each_entry(window, &host->windows, list) > >>>>>> + if (window->res->flags & IORESOURCE_BUS) { > >>>>>> + found = true; > >>>>>> + break; > >>>>>> + } > >>>>>> + > >>>>>> + host->bus = __pci_create_root_bus(host); > >>>>>> + if (!host->bus) { > >>>>>> + pci_free_host_bridge(host); > >>>>>> return NULL; > >>>>>> + } > >>>>>> > >>>>>> if (!found) { > >>>>>> - dev_info(&b->dev, > >>>>>> + dev_info(&host->bus->dev, > >>>>>> "No busn resource found for root bus, will use [bus %02x-ff]\n", > >>>>>> PCI_BUSNUM(db)); > >>>>>> - pci_bus_insert_busn_res(b, PCI_BUSNUM(db), 255); > >>>>>> + pci_bus_insert_busn_res(host->bus, PCI_BUSNUM(db), 255); > >>>>>> } > >>>>>> > >>>>>> - max = pci_scan_child_bus(b); > >>>>>> - > >>>>>> + max = pci_scan_child_bus(host->bus); > >>>>>> if (!found) > >>>>>> - pci_bus_update_busn_res_end(b, max); > >>>>>> + pci_bus_update_busn_res_end(host->bus, max); > >>>>>> > >>>>>> - return b; > >>>>>> + return host->bus; > >>>>>> } > >>>>>> EXPORT_SYMBOL(pci_scan_root_bus); > >>>>>> > >>>>>> diff --git a/include/linux/pci.h b/include/linux/pci.h > >>>>>> index 8b11b38..daa7f40 100644 > >>>>>> --- a/include/linux/pci.h > >>>>>> +++ b/include/linux/pci.h > >>>>>> @@ -402,7 +402,12 @@ struct pci_host_bridge_window { > >>>>>> struct pci_host_bridge { > >>>>>> struct device dev; > >>>>>> struct pci_bus *bus; /* root bus */ > >>>>>> + struct list_head list; > >>>>>> struct list_head windows; /* pci_host_bridge_windows */ > >>>>>> + int busnum; > >>>>>> + int domain; > >>>>>> + void *sysdata; > >>>>>> + struct pci_ops *ops; > >>>>>> void (*release_fn)(struct pci_host_bridge *); > >>>>>> void *release_data; > >>>>>> }; > >>>>>> @@ -413,7 +418,9 @@ void pci_set_host_bridge_release(struct pci_host_bridge *bridge, > >>>>>> void *release_data); > >>>>>> > >>>>>> int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge); > >>>>>> - > >>>>>> +struct pci_host_bridge *pci_create_host_bridge( > >>>>>> + struct device *parent, u32 db, struct pci_ops *ops, > >>>>>> + void *sys, struct list_head *resources); > >>>>>> /* > >>>>>> * The first PCI_BRIDGE_RESOURCE_NUM PCI bus resources (those that correspond > >>>>>> * to P2P or CardBus bridge windows) go in a table. Additional ones (for > >>>>>> @@ -770,6 +777,8 @@ void pci_bus_add_devices(const struct pci_bus *bus); > >>>>>> struct pci_bus *pci_create_root_bus(struct device *parent, u32 bus, > >>>>>> struct pci_ops *ops, void *sysdata, > >>>>>> struct list_head *resources); > >>>>>> +struct pci_bus *__pci_create_root_bus(struct pci_host_bridge *host); > >>>>>> +void pci_free_host_bridge(struct pci_host_bridge *host); > >>>>>> 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); > >>>>>> -- > >>>>>> 1.7.1 > >>>>>> > >>>>>> -- > >>>>>> To unsubscribe from this list: send the line "unsubscribe linux-pci" in > >>>>>> the body of a message to majordomo@vger.kernel.org > >>>>>> More majordomo info at http://vger.kernel.org/majordomo-info.html > >>>>>> > >>>>> > >>>> > >>>> > >>>> -- > >>>> Thanks! > >>>> Yijing > >>>> > >>>> -- > >>>> To unsubscribe from this list: send the line "unsubscribe linux-pci" in > >>>> the body of a message to majordomo@vger.kernel.org > >>>> More majordomo info at http://vger.kernel.org/majordomo-info.html > >>>> > >>> > >> > >> > >> -- > >> Thanks! > >> Yijing > >> > >> > > > > > -- > Thanks! > Yijing > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- ==================== | 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/