Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756365AbaKRPmt (ORCPT ); Tue, 18 Nov 2014 10:42:49 -0500 Received: from service87.mimecast.com ([91.220.42.44]:34526 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755398AbaKRPmr convert rfc822-to-8bit (ORCPT ); Tue, 18 Nov 2014 10:42:47 -0500 Date: Tue, 18 Nov 2014 15:42:43 +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" , Yijing Wang Subject: Re: [RFC PATCH 08/16] PCI: Introduce pci_scan_host_bridge() and pci_host_info Message-ID: <20141118154243.GM12037@e106497-lin.cambridge.arm.com> References: <1416219710-26088-1-git-send-email-wangyijing@huawei.com> <1416219710-26088-9-git-send-email-wangyijing@huawei.com> MIME-Version: 1.0 In-Reply-To: <1416219710-26088-9-git-send-email-wangyijing@huawei.com> User-Agent: Mutt/1.5.22 (2013-10-16) X-OriginalArrivalTime: 18 Nov 2014 15:42:44.0489 (UTC) FILETIME=[4B9C8F90:01D00346] X-MC-Unique: 114111815424505701 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 Mon, Nov 17, 2014 at 10:21:42AM +0000, Yijing Wang wrote: > From: Yijing Wang > > Now pci_host_bridge has been ripped out from pci root > bus creation. Currently pci_scan_root_bus() lacks > scalability, so platform host drivers have no proper > way to configure pci_host_bridge. E.g we should assign > msi_controller to pci_host_bridge, add argument for > pci_scan_root_bus() is not a good idea, it has already > five, so introudce struct pci_host_info to make > pci scan interfaces more scalable. Because almost > all host drivers need to configure host resources, > so we put .init_res() in it first, and add other > hooks when need. > > Signed-off-by: Yijing Wang > --- > drivers/pci/host-bridge.c | 27 +++++++++------- > drivers/pci/probe.c | 73 ++++++++++++++++++++++++++++++++++++++++++-- > include/linux/pci.h | 20 ++++++++++++- > 3 files changed, 103 insertions(+), 17 deletions(-) > > diff --git a/drivers/pci/host-bridge.c b/drivers/pci/host-bridge.c > index e31604f..49b6c21 100644 > --- a/drivers/pci/host-bridge.c > +++ b/drivers/pci/host-bridge.c > @@ -8,9 +8,6 @@ > > #include "pci.h" > > -LIST_HEAD(pci_host_bridge_list); > -DECLARE_RWSEM(pci_host_bridge_sem); > - > static struct resource busn_resource = { > .name = "PCI busn", > .start = 0, > @@ -18,6 +15,9 @@ static struct resource busn_resource = { > .flags = IORESOURCE_BUS, > }; > > +LIST_HEAD(pci_host_bridge_list); > +DECLARE_RWSEM(pci_host_bridge_sem); > + > static void pci_release_host_bridge_dev(struct device *dev) > { > struct pci_host_bridge *bridge = to_pci_host_bridge(dev); > @@ -29,14 +29,12 @@ static void pci_release_host_bridge_dev(struct device *dev) > } > > struct pci_host_bridge *pci_create_host_bridge( > - struct device *parent, u32 db, > - struct pci_ops *ops, void *sysdata, > - struct list_head *resources) > + struct device *parent, u32 db, struct pci_ops *ops, > + struct pci_host_info *info) > { > int error; > struct pci_bus *b; > struct pci_host_bridge *host, *h; > - struct pci_host_bridge_window *window, *n; > > down_read(&pci_host_bridge_sem); > list_for_each_entry(h, &pci_host_bridge_list, list) { > @@ -53,7 +51,7 @@ struct pci_host_bridge *pci_create_host_bridge( > if (!host) > return NULL; > > - host->sysdata = sysdata; > + host->sysdata = info->arg; > host->busnum = PCI_BUSNUM(db); > host->domain = PCI_DOMAIN(db); > host->ops = ops; > @@ -63,18 +61,23 @@ struct pci_host_bridge *pci_create_host_bridge( > > /* this is hack, just for build, will be removed later*/ Why do you need this hack? Just for calling pci_domain_nr() ? > b = kzalloc(sizeof(*b), GFP_KERNEL); > - b->sysdata = sysdata; > + b->sysdata = host->sysdata; > pci_bus_assign_domain_nr(b, parent); > host->domain = pci_domain_nr(b); > + kfree(b); > > - if (!resources) { > + if (info->res_type == PCI_HOST_RES_DEFAULT) { > /* Use default IO/MEM/BUS resources*/ > pci_add_resource(&host->windows, &ioport_resource); > pci_add_resource(&host->windows, &iomem_resource); > pci_add_resource(&host->windows, &busn_resource); > } else { > - list_for_each_entry_safe(window, n, resources, list) > - list_move_tail(&window->list, &host->windows); > + if (!info->init_res || info->init_res(host, info)) { > + pr_err("pci host %04x:%02x init resources fail\n", > + host->domain, host->busnum); > + kfree(host); > + return NULL; > + } > } > > dev_set_name(&host->dev, "pci%04x:%02x", host->domain, > diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c > index d472da4..42158fd 100644 > --- a/drivers/pci/probe.c > +++ b/drivers/pci/probe.c > @@ -1863,6 +1863,21 @@ void __weak pcibios_remove_bus(struct pci_bus *bus) > { > } > > +static int pci_default_init_res(struct pci_host_bridge *host, > + struct pci_host_info *info) > +{ > + struct pci_host_bridge_window *window, *n; > + > + if (info->res_type != PCI_HOST_RES_DEFAULT) > + list_for_each_entry_safe(window, n, info->resources, > + list) > + list_move_tail(&window->list, &host->windows); > + else > + info->res_type = PCI_HOST_RES_DEFAULT; I'm confused about this assignment. Isn't this a nop as the else part means info->res_type *is* PCI_HOST_RES_DEFAULT? > + > + return 0; > +} > + > struct pci_bus *__pci_create_root_bus(struct pci_host_bridge *bridge) > { > int error; > @@ -1949,13 +1964,17 @@ err_out: > return NULL; > } > > -struct pci_bus *pci_create_root_bus(struct device *parent, u32 bus, > +struct pci_bus *pci_create_root_bus(struct device *parent, u32 db, > struct pci_ops *ops, void *sysdata, struct list_head *resources) > { > struct pci_host_bridge *host; > + struct pci_host_info info; > + > + info.arg= sysdata; > + info.resources = resources; > + info.init_res = pci_default_init_res; > > - host = pci_create_host_bridge(parent, bus, ops, > - sysdata ,resources); > + host = pci_create_host_bridge(parent, db, ops, &info); > if (!host) > return NULL; > > @@ -2038,8 +2057,13 @@ struct pci_bus *pci_scan_root_bus(struct device *parent, u32 db, > bool found = false; > struct pci_host_bridge *host; > int max; > + struct pci_host_info info; > + > + info.arg = sysdata; > + info.resources = resources; > + info.init_res = pci_default_init_res; I have mixed feelings about this patch. While it is heading in the right direction of moving pci_host_bridge relevant information towards the right user, I don't think you picked up the right set to move. The resource list is going to be copied into internal pci_host_bridge list anyway, keeping another copy is not helpful *and* you have increased the code size. I think for now we should aim to get the *missing* data into pci_host_bridge: MSI controllers and PCI domain/segment. Then we can do more cleanup. > > - host = pci_create_host_bridge(parent, db, ops, sysdata, resources); > + host = pci_create_host_bridge(parent, db, ops, &info); > if (!host) > return NULL; > > @@ -2070,6 +2094,47 @@ struct pci_bus *pci_scan_root_bus(struct device *parent, u32 db, > } > EXPORT_SYMBOL(pci_scan_root_bus); > > +struct pci_host_bridge *pci_scan_host_bridge( > + struct device *parent, u32 db, struct pci_ops *ops, > + struct pci_host_info *info) > +{ > + struct pci_host_bridge_window *window; > + bool found = false; > + struct pci_host_bridge *host; > + int max; > + > + host = pci_create_host_bridge(parent, db, ops, info); > + if (!host) > + return NULL; > + > + 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(&host->bus->dev, > + "No busn resource found for root bus, will use [bus %02x-ff]\n", > + host->busnum); > + pci_bus_insert_busn_res(host->bus, host->busnum, 255); > + } > + > + max = pci_scan_child_bus(host->bus); > + if (!found) > + pci_bus_update_busn_res_end(host->bus, max); > + > + return host; > + > +} > +EXPORT_SYMBOL(pci_scan_host_bridge); > + > /** > * pci_rescan_bus_bridge_resize - scan a PCI bus for devices. > * @bridge: PCI bridge for the bus to scan > diff --git a/include/linux/pci.h b/include/linux/pci.h > index daa7f40..a51f5f5 100644 > --- a/include/linux/pci.h > +++ b/include/linux/pci.h > @@ -412,6 +412,21 @@ struct pci_host_bridge { > void *release_data; > }; > > +struct pci_host_info { > + u8 res_type; > + void *arg; > + struct list_head *resources; /*just for build, will clean up later */ > + int (*init_res)(struct pci_host_bridge *host, > + struct pci_host_info *info); > +}; > + > +static inline void init_pci_host_info(struct pci_host_info *info) > +{ > + memset(info, 0 , sizeof(*info)); > +} Where is this used? > + > +#define PCI_HOST_RES_DEFAULT 0x2 > + Magic number? Best regards, Liviu > #define to_pci_host_bridge(n) container_of(n, struct pci_host_bridge, dev) > void pci_set_host_bridge_release(struct pci_host_bridge *bridge, > void (*release_fn)(struct pci_host_bridge *), > @@ -420,7 +435,7 @@ void pci_set_host_bridge_release(struct pci_host_bridge *bridge, > 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); > + struct pci_host_info *info); > /* > * 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 > @@ -785,6 +800,9 @@ void pci_bus_release_busn_res(struct pci_bus *b); > struct pci_bus *pci_scan_root_bus(struct device *parent, u32 bus, > struct pci_ops *ops, void *sysdata, > struct list_head *resources); > +struct pci_host_bridge *pci_scan_host_bridge(struct device *parent, > + u32 db, struct pci_ops *ops, > + struct pci_host_info *info); > struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, > int busnr); > void pcie_update_link_speed(struct pci_bus *bus, u16 link_status); > -- > 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 > -- ==================== | 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/