drivers/pci/bus.c

   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
  21 void 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 }
  36 EXPORT_SYMBOL(pci_add_resource_offset);
  37
  38 void pci_add_resource(struct list_head *resources, struct resource *res)
  39 {
  40         pci_add_resource_offset(resources, res, 0);
  41 }
  42 EXPORT_SYMBOL(pci_add_resource);
  43
  44 void 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 }
  53 EXPORT_SYMBOL(pci_free_resource_list);
  54
  55 void 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
  71 struct 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 }
  85 EXPORT_SYMBOL_GPL(pci_bus_resource_n);
  86
  87 void 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  */
 116 int
 117 pci_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  */
 168 int 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  */
 194 int 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  */
 225 void 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
 269 void 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  */
 300 void 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 }
 334 EXPORT_SYMBOL_GPL(pci_walk_bus);
 335
 336 EXPORT_SYMBOL(pci_bus_alloc_resource);
 337 EXPORT_SYMBOL_GPL(pci_bus_add_device);
 338 EXPORT_SYMBOL(pci_bus_add_devices);
 339 EXPORT_SYMBOL(pci_enable_bridges);