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