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 18 #include "pci.h" 19 20 /** 21 * pci_bus_alloc_resource - allocate a resource from a parent bus 22 * @bus: PCI bus 23 * @res: resource to allocate 24 * @size: size of resource to allocate 25 * @align: alignment of resource to allocate 26 * @min: minimum /proc/iomem address to allocate 27 * @type_mask: IORESOURCE_* type flags 28 * @alignf: resource alignment function 29 * @alignf_data: data argument for resource alignment function 30 * 31 * Given the PCI bus a device resides on, the size, minimum address, 32 * alignment and type, try to find an acceptable resource allocation 33 * for a specific device resource. 34 */ 35 int 36 pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res, 37 resource_size_t size, resource_size_t align, 38 resource_size_t min, unsigned int type_mask, 39 resource_size_t (*alignf)(void *, 40 const struct resource *, 41 resource_size_t, 42 resource_size_t), 43 void *alignf_data) 44 { 45 int i, ret = -ENOMEM; 46 struct resource *r; 47 resource_size_t max = -1; 48 49 type_mask |= IORESOURCE_IO | IORESOURCE_MEM; 50 51 /* don't allocate too high if the pref mem doesn't support 64bit*/ 52 if (!(res->flags & IORESOURCE_MEM_64)) 53 max = PCIBIOS_MAX_MEM_32; 54 55 pci_bus_for_each_resource(bus, r, i) { 56 if (!r) 57 continue; 58 59 /* type_mask must match */ 60 if ((res->flags ^ r->flags) & type_mask) 61 continue; 62 63 /* We cannot allocate a non-prefetching resource 64 from a pre-fetching area */ 65 if ((r->flags & IORESOURCE_PREFETCH) && 66 !(res->flags & IORESOURCE_PREFETCH)) 67 continue; 68 69 /* Ok, try it out.. */ 70 ret = allocate_resource(r, res, size, 71 r->start ? : min, 72 max, align, 73 alignf, alignf_data); 74 if (ret == 0) 75 break; 76 } 77 return ret; 78 } 79 80 /** 81 * pci_bus_add_device - add a single device 82 * @dev: device to add 83 * 84 * This adds a single pci device to the global 85 * device list and adds sysfs and procfs entries 86 */ 87 int pci_bus_add_device(struct pci_dev *dev) 88 { 89 int retval; 90 retval = device_add(&dev->dev); 91 if (retval) 92 return retval; 93 94 dev->is_added = 1; 95 pci_proc_attach_device(dev); 96 pci_create_sysfs_dev_files(dev); 97 return 0; 98 } 99 100 /** 101 * pci_bus_add_child - add a child bus 102 * @bus: bus to add 103 * 104 * This adds sysfs entries for a single bus 105 */ 106 int pci_bus_add_child(struct pci_bus *bus) 107 { 108 int retval; 109 110 if (bus->bridge) 111 bus->dev.parent = bus->bridge; 112 113 retval = device_register(&bus->dev); 114 if (retval) 115 return retval; 116 117 bus->is_added = 1; 118 119 retval = device_create_file(&bus->dev, &dev_attr_cpuaffinity); 120 if (retval) 121 return retval; 122 123 retval = device_create_file(&bus->dev, &dev_attr_cpulistaffinity); 124 125 /* Create legacy_io and legacy_mem files for this bus */ 126 pci_create_legacy_files(bus); 127 128 return retval; 129 } 130 131 /** 132 * pci_bus_add_devices - insert newly discovered PCI devices 133 * @bus: bus to check for new devices 134 * 135 * Add newly discovered PCI devices (which are on the bus->devices 136 * list) to the global PCI device list, add the sysfs and procfs 137 * entries. Where a bridge is found, add the discovered bus to 138 * the parents list of child buses, and recurse (breadth-first 139 * to be compatible with 2.4) 140 * 141 * Call hotplug for each new devices. 142 */ 143 void pci_bus_add_devices(const struct pci_bus *bus) 144 { 145 struct pci_dev *dev; 146 struct pci_bus *child; 147 int retval; 148 149 list_for_each_entry(dev, &bus->devices, bus_list) { 150 /* Skip already-added devices */ 151 if (dev->is_added) 152 continue; 153 retval = pci_bus_add_device(dev); 154 if (retval) 155 dev_err(&dev->dev, "Error adding device, continuing\n"); 156 } 157 158 list_for_each_entry(dev, &bus->devices, bus_list) { 159 BUG_ON(!dev->is_added); 160 161 child = dev->subordinate; 162 /* 163 * If there is an unattached subordinate bus, attach 164 * it and then scan for unattached PCI devices. 165 */ 166 if (!child) 167 continue; 168 if (list_empty(&child->node)) { 169 down_write(&pci_bus_sem); 170 list_add_tail(&child->node, &dev->bus->children); 171 up_write(&pci_bus_sem); 172 } 173 pci_bus_add_devices(child); 174 175 /* 176 * register the bus with sysfs as the parent is now 177 * properly registered. 178 */ 179 if (child->is_added) 180 continue; 181 retval = pci_bus_add_child(child); 182 if (retval) 183 dev_err(&dev->dev, "Error adding bus, continuing\n"); 184 } 185 } 186 187 void pci_enable_bridges(struct pci_bus *bus) 188 { 189 struct pci_dev *dev; 190 int retval; 191 192 list_for_each_entry(dev, &bus->devices, bus_list) { 193 if (dev->subordinate) { 194 if (!pci_is_enabled(dev)) { 195 retval = pci_enable_device(dev); 196 pci_set_master(dev); 197 } 198 pci_enable_bridges(dev->subordinate); 199 } 200 } 201 } 202 203 /** pci_walk_bus - walk devices on/under bus, calling callback. 204 * @top bus whose devices should be walked 205 * @cb callback to be called for each device found 206 * @userdata arbitrary pointer to be passed to callback. 207 * 208 * Walk the given bus, including any bridged devices 209 * on buses under this bus. Call the provided callback 210 * on each device found. 211 * 212 * We check the return of @cb each time. If it returns anything 213 * other than 0, we break out. 214 * 215 */ 216 void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), 217 void *userdata) 218 { 219 struct pci_dev *dev; 220 struct pci_bus *bus; 221 struct list_head *next; 222 int retval; 223 224 bus = top; 225 down_read(&pci_bus_sem); 226 next = top->devices.next; 227 for (;;) { 228 if (next == &bus->devices) { 229 /* end of this bus, go up or finish */ 230 if (bus == top) 231 break; 232 next = bus->self->bus_list.next; 233 bus = bus->self->bus; 234 continue; 235 } 236 dev = list_entry(next, struct pci_dev, bus_list); 237 if (dev->subordinate) { 238 /* this is a pci-pci bridge, do its devices next */ 239 next = dev->subordinate->devices.next; 240 bus = dev->subordinate; 241 } else 242 next = dev->bus_list.next; 243 244 /* Run device routines with the device locked */ 245 down(&dev->dev.sem); 246 retval = cb(dev, userdata); 247 up(&dev->dev.sem); 248 if (retval) 249 break; 250 } 251 up_read(&pci_bus_sem); 252 } 253 254 EXPORT_SYMBOL(pci_bus_alloc_resource); 255 EXPORT_SYMBOL_GPL(pci_bus_add_device); 256 EXPORT_SYMBOL(pci_bus_add_devices); 257 EXPORT_SYMBOL(pci_enable_bridges); 258