linux/drivers/pci/bus.c
<<
>>
Prefs
   1/*
   2 *      drivers/pci/bus.c
   3 *
   4 * From setup-res.c, by:
   5 *      Dave Rusling (david.rusling@reo.mts.dec.com)
   6 *      David Mosberger (davidm@cs.arizona.edu)
   7 *      David Miller (davem@redhat.com)
   8 *      Ivan Kokshaysky (ink@jurassic.park.msu.ru)
   9 */
  10#include <linux/module.h>
  11#include <linux/kernel.h>
  12#include <linux/pci.h>
  13#include <linux/errno.h>
  14#include <linux/ioport.h>
  15#include <linux/proc_fs.h>
  16#include <linux/init.h>
  17#include <linux/slab.h>
  18
  19#include "pci.h"
  20
  21void pci_add_resource_offset(struct list_head *resources, struct resource *res,
  22                             resource_size_t offset)
  23{
  24        struct pci_host_bridge_window *window;
  25
  26        window = kzalloc(sizeof(struct pci_host_bridge_window), GFP_KERNEL);
  27        if (!window) {
  28                printk(KERN_ERR "PCI: can't add host bridge window %pR\n", res);
  29                return;
  30        }
  31
  32        window->res = res;
  33        window->offset = offset;
  34        list_add_tail(&window->list, resources);
  35}
  36EXPORT_SYMBOL(pci_add_resource_offset);
  37
  38void pci_add_resource(struct list_head *resources, struct resource *res)
  39{
  40        pci_add_resource_offset(resources, res, 0);
  41}
  42EXPORT_SYMBOL(pci_add_resource);
  43
  44void pci_free_resource_list(struct list_head *resources)
  45{
  46        struct pci_host_bridge_window *window, *tmp;
  47
  48        list_for_each_entry_safe(window, tmp, resources, list) {
  49                list_del(&window->list);
  50                kfree(window);
  51        }
  52}
  53EXPORT_SYMBOL(pci_free_resource_list);
  54
  55void pci_bus_add_resource(struct pci_bus *bus, struct resource *res,
  56                          unsigned int flags)
  57{
  58        struct pci_bus_resource *bus_res;
  59
  60        bus_res = kzalloc(sizeof(struct pci_bus_resource), GFP_KERNEL);
  61        if (!bus_res) {
  62                dev_err(&bus->dev, "can't add %pR resource\n", res);
  63                return;
  64        }
  65
  66        bus_res->res = res;
  67        bus_res->flags = flags;
  68        list_add_tail(&bus_res->list, &bus->resources);
  69}
  70
  71struct resource *pci_bus_resource_n(const struct pci_bus *bus, int n)
  72{
  73        struct pci_bus_resource *bus_res;
  74
  75        if (n < PCI_BRIDGE_RESOURCE_NUM)
  76                return bus->resource[n];
  77
  78        n -= PCI_BRIDGE_RESOURCE_NUM;
  79        list_for_each_entry(bus_res, &bus->resources, list) {
  80                if (n-- == 0)
  81                        return bus_res->res;
  82        }
  83        return NULL;
  84}
  85EXPORT_SYMBOL_GPL(pci_bus_resource_n);
  86
  87void pci_bus_remove_resources(struct pci_bus *bus)
  88{
  89        int i;
  90        struct pci_bus_resource *bus_res, *tmp;
  91
  92        for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
  93                bus->resource[i] = NULL;
  94
  95        list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) {
  96                list_del(&bus_res->list);
  97                kfree(bus_res);
  98        }
  99}
 100
 101/**
 102 * pci_bus_alloc_resource - allocate a resource from a parent bus
 103 * @bus: PCI bus
 104 * @res: resource to allocate
 105 * @size: size of resource to allocate
 106 * @align: alignment of resource to allocate
 107 * @min: minimum /proc/iomem address to allocate
 108 * @type_mask: IORESOURCE_* type flags
 109 * @alignf: resource alignment function
 110 * @alignf_data: data argument for resource alignment function
 111 *
 112 * Given the PCI bus a device resides on, the size, minimum address,
 113 * alignment and type, try to find an acceptable resource allocation
 114 * for a specific device resource.
 115 */
 116int
 117pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
 118                resource_size_t size, resource_size_t align,
 119                resource_size_t min, unsigned int type_mask,
 120                resource_size_t (*alignf)(void *,
 121                                          const struct resource *,
 122                                          resource_size_t,
 123                                          resource_size_t),
 124                void *alignf_data)
 125{
 126        int i, ret = -ENOMEM;
 127        struct resource *r;
 128        resource_size_t max = -1;
 129
 130        type_mask |= IORESOURCE_IO | IORESOURCE_MEM;
 131
 132        /* don't allocate too high if the pref mem doesn't support 64bit*/
 133        if (!(res->flags & IORESOURCE_MEM_64))
 134                max = PCIBIOS_MAX_MEM_32;
 135
 136        pci_bus_for_each_resource(bus, r, i) {
 137                if (!r)
 138                        continue;
 139
 140                /* type_mask must match */
 141                if ((res->flags ^ r->flags) & type_mask)
 142                        continue;
 143
 144                /* We cannot allocate a non-prefetching resource
 145                   from a pre-fetching area */
 146                if ((r->flags & IORESOURCE_PREFETCH) &&
 147                    !(res->flags & IORESOURCE_PREFETCH))
 148                        continue;
 149
 150                /* Ok, try it out.. */
 151                ret = allocate_resource(r, res, size,
 152                                        r->start ? : min,
 153                                        max, align,
 154                                        alignf, alignf_data);
 155                if (ret == 0)
 156                        break;
 157        }
 158        return ret;
 159}
 160
 161/**
 162 * pci_bus_add_device - add a single device
 163 * @dev: device to add
 164 *
 165 * This adds a single pci device to the global
 166 * device list and adds sysfs and procfs entries
 167 */
 168int pci_bus_add_device(struct pci_dev *dev)
 169{
 170        int retval;
 171
 172        pci_fixup_device(pci_fixup_final, dev);
 173
 174        retval = pcibios_add_device(dev);
 175        if (retval)
 176                return retval;
 177
 178        retval = device_add(&dev->dev);
 179        if (retval)
 180                return retval;
 181
 182        dev->is_added = 1;
 183        pci_proc_attach_device(dev);
 184        pci_create_sysfs_dev_files(dev);
 185        return 0;
 186}
 187
 188/**
 189 * pci_bus_add_child - add a child bus
 190 * @bus: bus to add
 191 *
 192 * This adds sysfs entries for a single bus
 193 */
 194int pci_bus_add_child(struct pci_bus *bus)
 195{
 196        int retval;
 197
 198        if (bus->bridge)
 199                bus->dev.parent = bus->bridge;
 200
 201        retval = device_register(&bus->dev);
 202        if (retval)
 203                return retval;
 204
 205        bus->is_added = 1;
 206
 207        /* Create legacy_io and legacy_mem files for this bus */
 208        pci_create_legacy_files(bus);
 209
 210        return retval;
 211}
 212
 213/**
 214 * pci_bus_add_devices - insert newly discovered PCI devices
 215 * @bus: bus to check for new devices
 216 *
 217 * Add newly discovered PCI devices (which are on the bus->devices
 218 * list) to the global PCI device list, add the sysfs and procfs
 219 * entries.  Where a bridge is found, add the discovered bus to
 220 * the parents list of child buses, and recurse (breadth-first
 221 * to be compatible with 2.4)
 222 *
 223 * Call hotplug for each new devices.
 224 */
 225void pci_bus_add_devices(const struct pci_bus *bus)
 226{
 227        struct pci_dev *dev;
 228        struct pci_bus *child;
 229        int retval;
 230
 231        list_for_each_entry(dev, &bus->devices, bus_list) {
 232                /* Skip already-added devices */
 233                if (dev->is_added)
 234                        continue;
 235                retval = pci_bus_add_device(dev);
 236                if (retval)
 237                        dev_err(&dev->dev, "Error adding device, continuing\n");
 238        }
 239
 240        list_for_each_entry(dev, &bus->devices, bus_list) {
 241                BUG_ON(!dev->is_added);
 242
 243                child = dev->subordinate;
 244                /*
 245                 * If there is an unattached subordinate bus, attach
 246                 * it and then scan for unattached PCI devices.
 247                 */
 248                if (!child)
 249                        continue;
 250                if (list_empty(&child->node)) {
 251                        down_write(&pci_bus_sem);
 252                        list_add_tail(&child->node, &dev->bus->children);
 253                        up_write(&pci_bus_sem);
 254                }
 255                pci_bus_add_devices(child);
 256
 257                /*
 258                 * register the bus with sysfs as the parent is now
 259                 * properly registered.
 260                 */
 261                if (child->is_added)
 262                        continue;
 263                retval = pci_bus_add_child(child);
 264                if (retval)
 265                        dev_err(&dev->dev, "Error adding bus, continuing\n");
 266        }
 267}
 268
 269void pci_enable_bridges(struct pci_bus *bus)
 270{
 271        struct pci_dev *dev;
 272        int retval;
 273
 274        list_for_each_entry(dev, &bus->devices, bus_list) {
 275                if (dev->subordinate) {
 276                        if (!pci_is_enabled(dev)) {
 277                                retval = pci_enable_device(dev);
 278                                if (retval)
 279                                        dev_err(&dev->dev, "Error enabling bridge (%d), continuing\n", retval);
 280                                pci_set_master(dev);
 281                        }
 282                        pci_enable_bridges(dev->subordinate);
 283                }
 284        }
 285}
 286
 287/** pci_walk_bus - walk devices on/under bus, calling callback.
 288 *  @top      bus whose devices should be walked
 289 *  @cb       callback to be called for each device found
 290 *  @userdata arbitrary pointer to be passed to callback.
 291 *
 292 *  Walk the given bus, including any bridged devices
 293 *  on buses under this bus.  Call the provided callback
 294 *  on each device found.
 295 *
 296 *  We check the return of @cb each time. If it returns anything
 297 *  other than 0, we break out.
 298 *
 299 */
 300void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
 301                  void *userdata)
 302{
 303        struct pci_dev *dev;
 304        struct pci_bus *bus;
 305        struct list_head *next;
 306        int retval;
 307
 308        bus = top;
 309        down_read(&pci_bus_sem);
 310        next = top->devices.next;
 311        for (;;) {
 312                if (next == &bus->devices) {
 313                        /* end of this bus, go up or finish */
 314                        if (bus == top)
 315                                break;
 316                        next = bus->self->bus_list.next;
 317                        bus = bus->self->bus;
 318                        continue;
 319                }
 320                dev = list_entry(next, struct pci_dev, bus_list);
 321                if (dev->subordinate) {
 322                        /* this is a pci-pci bridge, do its devices next */
 323                        next = dev->subordinate->devices.next;
 324                        bus = dev->subordinate;
 325                } else
 326                        next = dev->bus_list.next;
 327
 328                retval = cb(dev, userdata);
 329                if (retval)
 330                        break;
 331        }
 332        up_read(&pci_bus_sem);
 333}
 334EXPORT_SYMBOL_GPL(pci_walk_bus);
 335
 336EXPORT_SYMBOL(pci_bus_alloc_resource);
 337EXPORT_SYMBOL_GPL(pci_bus_add_device);
 338EXPORT_SYMBOL(pci_bus_add_devices);
 339EXPORT_SYMBOL(pci_enable_bridges);
 340
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.