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