From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from service87.mimecast.com (service87.mimecast.com [91.220.42.44]) by lists.ozlabs.org (Postfix) with ESMTP id 76C041A0668 for ; Fri, 21 Nov 2014 20:53:17 +1100 (AEDT) Date: Fri, 21 Nov 2014 09:53:12 +0000 From: Liviu Dudau To: Yijing Wang 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> Content-Type: text/plain; charset=UTF-8 Cc: Liviu Dudau , Tony Luck , Russell King , "linux-pci@vger.kernel.org" , "x86@kernel.org" , "linux-kernel@vger.kernel.org" , "huxinwei@huawei.com" , Thierry Reding , "suravee.suthikulpanit@amd.com" , Bjorn Helgaas , "linux-ia64@vger.kernel.org" , Thomas Gleixner , Wuyun , "linuxppc-dev@lists.ozlabs.org" , "linux-arm-kernel@lists.infradead.org" List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 a= ny other HB > >>> specific stuff, you use the HB ops. For config R/W acceses you use bu= s ops. > >>> > >> > >> I want to unexport pci_create_root_bus() if we have pci_create_host_br= idge(). > > > > That's fine, but the function signature doesn't change, right? And I th= ink we should keep > > pci_scan_root_bus() with the current signature as well (except change s= ysdata 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(). >=20 > Liviu, could you have some draft patches about replace sysdata with pci_h= ost_bridge, so we could > discuss the details base it. :) Sure, I'll try to send something soon. Best regards, Liviu >=20 > > > > Hope this makes sense. > > > >> > >> > >>>>>> -struct pci_bus *pci_create_root_bus(struct device *parent, u32 db= , > >>>>>> - struct pci_ops *ops, void *sysdata, struct list_he= ad *resources) > >>>>>> +struct pci_bus *__pci_create_root_bus(struct pci_host_bridge *bri= dge) > >>>>>> { > >>>>>> 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 =3D PCI_BUSNUM(db); > >>>>>> + struct device *parent =3D bridge->dev.parent; > >>>>>> > >>>>>> b =3D pci_alloc_bus(NULL); > >>>>>> if (!b) > >>>>>> return NULL; > >>>>>> > >>>>>> - b->sysdata =3D sysdata; > >>>>>> - b->ops =3D ops; > >>>>>> - b->number =3D b->busn_res.start =3D bus; > >>>>>> + b->sysdata =3D 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 bridg= e structure, as passed > >>> in pci_create_root_bus(). If you agree with my idea of wrapping the h= ost 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->sysdat= a to be the bridge. > >>> Then existing macros that convert sysdata to pci_controller can be re= used 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_brid= ge 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 becau= se 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 advan= tage ? > > > > Agree, the macro is not useful unless we have a common pci_controller s= tructure. 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 sy= sdata 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. >=20 > Fine. >=20 > > > > Best regards, > > Liviu > > > >> > >> > >> > >>> > >>> Best regards, > >>> Liviu > >>> > >>>> > >>>>> > >>>>>> + b->ops =3D bridge->ops; > >>>>> > >>>>> See comment above why I don't think this is necessary. > >>>>> > >>>>>> + b->number =3D b->busn_res.start =3D bridge->busnum; > >>>>>> pci_bus_assign_domain_nr(b, parent); > >>>>>> - b2 =3D pci_find_bus(pci_domain_nr(b), bus); > >>>>>> + bridge->domain =3D pci_domain_nr(b); > >>>>> > >>>>> Do you really want to overwrite the bridge's domain with the one fr= om 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 roo= t bus creation > >>>>> it is worth in my opinion to move the domain setup in pci_create_ho= st_bridge() > >>>>> and stop fiddling with it here. > >>>> > >>>> > >>>> Hi Liviu, these lines just temporary, I will remove it after all hos= t drivers > >>>> save its domain in pci_host_bridge. > >>>> > >>>> > >>>>> > >>>>> Otherwise it looks to me like you are heading in the right directio= n. > >>>> > >>>> Thanks! > >>>> Yijing. > >>>> > >>>>> > >>>>> Best regards, > >>>>> Liviu > >>>>> > >>>>>> + b2 =3D pci_find_bus(pci_domain_nr(b), bridge->busnum); > >>>>>> if (b2) { > >>>>>> /* If we already got to this bus through a differe= nt bridge, ignore it */ > >>>>>> dev_dbg(&b2->dev, "bus already known\n"); > >>>>>> goto err_out; > >>>>>> } > >>>>>> > >>>>>> - bridge =3D pci_alloc_host_bridge(b); > >>>>>> - if (!bridge) > >>>>>> - goto err_out; > >>>>>> - > >>>>>> - bridge->dev.parent =3D parent; > >>>>>> - bridge->dev.release =3D pci_release_host_bridge_dev; > >>>>>> - dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b= ), bus); > >>>>>> - error =3D pcibios_root_bridge_prepare(bridge); > >>>>>> - if (error) { > >>>>>> - kfree(bridge); > >>>>>> - goto err_out; > >>>>>> - } > >>>>>> - > >>>>>> - error =3D device_register(&bridge->dev); > >>>>>> - if (error) { > >>>>>> - put_device(&bridge->dev); > >>>>>> - goto err_out; > >>>>>> - } > >>>>>> b->bridge =3D 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 d= evice *parent, u32 db, > >>>>>> > >>>>>> b->dev.class =3D &pcibus_class; > >>>>>> b->dev.parent =3D 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->nu= mber); > >>>>>> error =3D 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", de= v_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 =3D window->res; > >>>>>> offset =3D 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 bu= s, > >>>>>> + struct pci_ops *ops, void *sysdata, struct list_he= ad *resources) > >>>>>> +{ > >>>>>> + struct pci_host_bridge *host; > >>>>>> + > >>>>>> + host =3D pci_create_host_bridge(parent, bus, ops, > >>>>>> + sysdata ,resources); > >>>>>> + if (!host) > >>>>>> + return NULL; > >>>>>> + > >>>>>> + host->bus =3D __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_m= ax) > >>>>>> { > >>>>>> struct resource *res =3D &b->busn_res; > >>>>>> @@ -2069,40 +2036,37 @@ struct pci_bus *pci_scan_root_bus(struct d= evice *parent, u32 db, > >>>>>> { > >>>>>> struct pci_host_bridge_window *window; > >>>>>> bool found =3D 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 =3D true; > >>>>>> - break; > >>>>>> - } > >>>>>> - } > >>>>>> + host =3D pci_create_host_bridge(parent, db, ops, sysdata, = resources); > >>>>>> + if (!host) > >>>>>> + return NULL; > >>>>>> > >>>>>> - b =3D 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 =3D true; > >>>>>> + break; > >>>>>> + } > >>>>>> + > >>>>>> + host->bus =3D __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 [b= us %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 =3D pci_scan_child_bus(b); > >>>>>> - > >>>>>> + max =3D 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_ho= st_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 tha= t correspond > >>>>>> * to P2P or CardBus bridge windows) go in a table. Additional o= nes (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 bu= s, > >>>>>> struct pci_ops *ops, void *sys= data, > >>>>>> struct list_head *resources); > >>>>>> +struct pci_bus *__pci_create_root_bus(struct pci_host_bridge *hos= t); > >>>>>> +void pci_free_host_bridge(struct pci_host_bridge *host); > >>>>>> int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int busma= x); > >>>>>> 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-pc= i" 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 > >> > >> > > >=20 >=20 > -- > Thanks! > Yijing >=20 > -- > 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 >=20 --=20 =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- =C2=AF\_(=E3=83=84)_/=C2=AF