From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757203AbaKUCz4 (ORCPT ); Thu, 20 Nov 2014 21:55:56 -0500 Received: from szxga02-in.huawei.com ([119.145.14.65]:55222 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756132AbaKUCzx (ORCPT ); Thu, 20 Nov 2014 21:55:53 -0500 Message-ID: <546EA90D.3040304@huawei.com> Date: Fri, 21 Nov 2014 10:53:01 +0800 From: Yijing Wang User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20100101 Thunderbird/24.0.1 MIME-Version: 1.0 To: Liviu Dudau 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() 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> In-Reply-To: <20141120094741.GA17214@e106497-lin.cambridge.arm.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.27.212] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>> 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. :) > > 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