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_bus_add_resource(struct pci_bus *bus, struct resource *res, 22 unsigned int flags) 23 { 24 struct pci_bus_resource *bus_res; 25 26 bus_res = kzalloc(sizeof(struct pci_bus_resource), GFP_KERNEL); 27 if (!bus_res) { 28 dev_err(&bus->dev, "can't add %pR resource\n", res); 29 return; 30 } 31 32 bus_res->res = res; 33 bus_res->flags = flags; 34 list_add_tail(&bus_res->list, &bus->resources); 35 } 36 37 struct resource *pci_bus_resource_n(const struct pci_bus *bus, int n) 38 { 39 struct pci_bus_resource *bus_res; 40 41 if (n < PCI_BRIDGE_RESOURCE_NUM) 42 return bus->resource[n]; 43 44 n -= PCI_BRIDGE_RESOURCE_NUM; 45 list_for_each_entry(bus_res, &bus->resources, list) { 46 if (n-- == 0) 47 return bus_res->res; 48 } 49 return NULL; 50 } 51 EXPORT_SYMBOL_GPL(pci_bus_resource_n); 52 53 void pci_bus_remove_resources(struct pci_bus *bus) 54 { 55 struct pci_bus_resource *bus_res, *tmp; 56 int i; 57 58 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) 59 bus->resource[i] = NULL; 60 61 list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) { 62 list_del(&bus_res->list); 63 kfree(bus_res); 64 } 65 } 66 67 /** 68 * pci_bus_alloc_resource - allocate a resource from a parent bus 69 * @bus: PCI bus 70 * @res: resource to allocate 71 * @size: size of resource to allocate 72 * @align: alignment of resource to allocate 73 * @min: minimum /proc/iomem address to allocate 74 * @type_mask: IORESOURCE_* type flags 75 * @alignf: resource alignment function 76 * @alignf_data: data argument for resource alignment function 77 * 78 * Given the PCI bus a device resides on, the size, minimum address, 79 * alignment and type, try to find an acceptable resource allocation 80 * for a specific device resource. 81 */ 82 int 83 pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res, 84 resource_size_t size, resource_size_t align, 85 resource_size_t min, unsigned int type_mask, 86 resource_size_t (*alignf)(void *, 87 const struct resource *, 88 resource_size_t, 89 resource_size_t), 90 void *alignf_data) 91 { 92 int i, ret = -ENOMEM; 93 struct resource *r; 94 resource_size_t max = -1; 95 96 type_mask |= IORESOURCE_IO | IORESOURCE_MEM; 97 98 /* don't allocate too high if the pref mem doesn't support 64bit*/ 99 if (!(res->flags & IORESOURCE_MEM_64)) 100 max = PCIBIOS_MAX_MEM_32; 101 102 pci_bus_for_each_resource(bus, r, i) { 103 if (!r) 104 continue; 105 106 /* type_mask must match */ 107 if ((res->flags ^ r->flags) & type_mask) 108 continue; 109 110 /* We cannot allocate a non-prefetching resource 111 from a pre-fetching area */ 112 if ((r->flags & IORESOURCE_PREFETCH) && 113 !(res->flags & IORESOURCE_PREFETCH)) 114 continue; 115 116 /* Ok, try it out.. */ 117 ret = allocate_resource(r, res, size, 118 r->start ? : min, 119 max, align, 120 alignf, alignf_data); 121 if (ret == 0) 122 break; 123 } 124 return ret; 125 } 126 127 /** 128 * pci_bus_add_device - add a single device 129 * @dev: device to add 130 * 131 * This adds a single pci device to the global 132 * device list and adds sysfs and procfs entries 133 */ 134 int pci_bus_add_device(struct pci_dev *dev) 135 { 136 int retval; 137 retval = device_add(&dev->dev); 138 if (retval) 139 return retval; 140 141 dev->is_added = 1; 142 pci_proc_attach_device(dev); 143 pci_create_sysfs_dev_files(dev); 144 return 0; 145 } 146 147 /** 148 * pci_bus_add_child - add a child bus 149 * @bus: bus to add 150 * 151 * This adds sysfs entries for a single bus 152 */ 153 int pci_bus_add_child(struct pci_bus *bus) 154 { 155 int retval; 156 157 if (bus->bridge) 158 bus->dev.parent = bus->bridge; 159 160 retval = device_register(&bus->dev); 161 if (retval) 162 return retval; 163 164 bus->is_added = 1; 165 166 retval = device_create_file(&bus->dev, &dev_attr_cpuaffinity); 167 if (retval) 168 return retval; 169 170 retval = device_create_file(&bus->dev, &dev_attr_cpulistaffinity); 171 172 /* Create legacy_io and legacy_mem files for this bus */ 173 pci_create_legacy_files(bus); 174 175 return retval; 176 } 177 178 /** 179 * pci_bus_add_devices - insert newly discovered PCI devices 180 * @bus: bus to check for new devices 181 * 182 * Add newly discovered PCI devices (which are on the bus->devices 183 * list) to the global PCI device list, add the sysfs and procfs 184 * entries. Where a bridge is found, add the discovered bus to 185 * the parents list of child buses, and recurse (breadth-first 186 * to be compatible with 2.4) 187 * 188 * Call hotplug for each new devices. 189 */ 190 void pci_bus_add_devices(const struct pci_bus *bus) 191 { 192 struct pci_dev *dev; 193 struct pci_bus *child; 194 int retval; 195 196 list_for_each_entry(dev, &bus->devices, bus_list) { 197 /* Skip already-added devices */ 198 if (dev->is_added) 199 continue; 200 retval = pci_bus_add_device(dev); 201 if (retval) 202 dev_err(&dev->dev, "Error adding device, continuing\n"); 203 } 204 205 list_for_each_entry(dev, &bus->devices, bus_list) { 206 BUG_ON(!dev->is_added); 207 208 child = dev->subordinate; 209 /* 210 * If there is an unattached subordinate bus, attach 211 * it and then scan for unattached PCI devices. 212 */ 213 if (!child) 214 continue; 215 if (list_empty(&child->node)) { 216 down_write(&pci_bus_sem); 217 list_add_tail(&child->node, &dev->bus->children); 218 up_write(&pci_bus_sem); 219 } 220 pci_bus_add_devices(child); 221 222 /* 223 * register the bus with sysfs as the parent is now 224 * properly registered. 225 */ 226 if (child->is_added) 227 continue; 228 retval = pci_bus_add_child(child); 229 if (retval) 230 dev_err(&dev->dev, "Error adding bus, continuing\n"); 231 } 232 } 233 234 void pci_enable_bridges(struct pci_bus *bus) 235 { 236 struct pci_dev *dev; 237 int retval; 238 239 list_for_each_entry(dev, &bus->devices, bus_list) { 240 if (dev->subordinate) { 241 if (!pci_is_enabled(dev)) { 242 retval = pci_enable_device(dev); 243 if (retval) 244 dev_err(&dev->dev, "Error enabling bridge (%d), continuing\n", retval); 245 pci_set_master(dev); 246 } 247 pci_enable_bridges(dev->subordinate); 248 } 249 } 250 } 251 252 /** pci_walk_bus - walk devices on/under bus, calling callback. 253 * @top bus whose devices should be walked 254 * @cb callback to be called for each device found 255 * @userdata arbitrary pointer to be passed to callback. 256 * 257 * Walk the given bus, including any bridged devices 258 * on buses under this bus. Call the provided callback 259 * on each device found. 260 * 261 * We check the return of @cb each time. If it returns anything 262 * other than 0, we break out. 263 * 264 */ 265 void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), 266 void *userdata) 267 { 268 struct pci_dev *dev; 269 struct pci_bus *bus; 270 struct list_head *next; 271 int retval; 272 273 bus = top; 274 down_read(&pci_bus_sem); 275 next = top->devices.next; 276 for (;;) { 277 if (next == &bus->devices) { 278 /* end of this bus, go up or finish */ 279 if (bus == top) 280 break; 281 next = bus->self->bus_list.next; 282 bus = bus->self->bus; 283 continue; 284 } 285 dev = list_entry(next, struct pci_dev, bus_list); 286 if (dev->subordinate) { 287 /* this is a pci-pci bridge, do its devices next */ 288 next = dev->subordinate->devices.next; 289 bus = dev->subordinate; 290 } else 291 next = dev->bus_list.next; 292 293 /* Run device routines with the device locked */ 294 device_lock(&dev->dev); 295 retval = cb(dev, userdata); 296 device_unlock(&dev->dev); 297 if (retval) 298 break; 299 } 300 up_read(&pci_bus_sem); 301 } 302 303 EXPORT_SYMBOL(pci_bus_alloc_resource); 304 EXPORT_SYMBOL_GPL(pci_bus_add_device); 305 EXPORT_SYMBOL(pci_bus_add_devices); 306 EXPORT_SYMBOL(pci_enable_bridges); 307