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 dev->is_added = 1; 88 pci_proc_attach_device(dev); 89 pci_create_sysfs_dev_files(dev); 90 return 0; 91 } 92 93 /** 94 * pci_bus_add_devices - insert newly discovered PCI devices 95 * @bus: bus to check for new devices 96 * 97 * Add newly discovered PCI devices (which are on the bus->devices 98 * list) to the global PCI device list, add the sysfs and procfs 99 * entries. Where a bridge is found, add the discovered bus to 100 * the parents list of child buses, and recurse (breadth-first 101 * to be compatible with 2.4) 102 * 103 * Call hotplug for each new devices. 104 */ 105 void pci_bus_add_devices(struct pci_bus *bus) 106 { 107 struct pci_dev *dev; 108 struct pci_bus *child_bus; 109 int retval; 110 111 list_for_each_entry(dev, &bus->devices, bus_list) { 112 /* Skip already-added devices */ 113 if (dev->is_added) 114 continue; 115 retval = pci_bus_add_device(dev); 116 if (retval) 117 dev_err(&dev->dev, "Error adding device, continuing\n"); 118 } 119 120 list_for_each_entry(dev, &bus->devices, bus_list) { 121 BUG_ON(!dev->is_added); 122 123 /* 124 * If there is an unattached subordinate bus, attach 125 * it and then scan for unattached PCI devices. 126 */ 127 if (dev->subordinate) { 128 if (list_empty(&dev->subordinate->node)) { 129 down_write(&pci_bus_sem); 130 list_add_tail(&dev->subordinate->node, 131 &dev->bus->children); 132 up_write(&pci_bus_sem); 133 } 134 pci_bus_add_devices(dev->subordinate); 135 136 /* register the bus with sysfs as the parent is now 137 * properly registered. */ 138 child_bus = dev->subordinate; 139 if (child_bus->is_added) 140 continue; 141 child_bus->dev.parent = child_bus->bridge; 142 retval = device_register(&child_bus->dev); 143 if (retval) 144 dev_err(&dev->dev, "Error registering pci_bus," 145 " continuing...\n"); 146 else { 147 child_bus->is_added = 1; 148 retval = device_create_file(&child_bus->dev, 149 &dev_attr_cpuaffinity); 150 } 151 if (retval) 152 dev_err(&dev->dev, "Error creating cpuaffinity" 153 " file, continuing...\n"); 154 155 retval = device_create_file(&child_bus->dev, 156 &dev_attr_cpulistaffinity); 157 if (retval) 158 dev_err(&dev->dev, 159 "Error creating cpulistaffinity" 160 " file, continuing...\n"); 161 } 162 } 163 } 164 165 void pci_enable_bridges(struct pci_bus *bus) 166 { 167 struct pci_dev *dev; 168 int retval; 169 170 list_for_each_entry(dev, &bus->devices, bus_list) { 171 if (dev->subordinate) { 172 retval = pci_enable_device(dev); 173 pci_set_master(dev); 174 pci_enable_bridges(dev->subordinate); 175 } 176 } 177 } 178 179 /** pci_walk_bus - walk devices on/under bus, calling callback. 180 * @top bus whose devices should be walked 181 * @cb callback to be called for each device found 182 * @userdata arbitrary pointer to be passed to callback. 183 * 184 * Walk the given bus, including any bridged devices 185 * on buses under this bus. Call the provided callback 186 * on each device found. 187 */ 188 void pci_walk_bus(struct pci_bus *top, void (*cb)(struct pci_dev *, void *), 189 void *userdata) 190 { 191 struct pci_dev *dev; 192 struct pci_bus *bus; 193 struct list_head *next; 194 195 bus = top; 196 down_read(&pci_bus_sem); 197 next = top->devices.next; 198 for (;;) { 199 if (next == &bus->devices) { 200 /* end of this bus, go up or finish */ 201 if (bus == top) 202 break; 203 next = bus->self->bus_list.next; 204 bus = bus->self->bus; 205 continue; 206 } 207 dev = list_entry(next, struct pci_dev, bus_list); 208 if (dev->subordinate) { 209 /* this is a pci-pci bridge, do its devices next */ 210 next = dev->subordinate->devices.next; 211 bus = dev->subordinate; 212 } else 213 next = dev->bus_list.next; 214 215 /* Run device routines with the device locked */ 216 down(&dev->dev.sem); 217 cb(dev, userdata); 218 up(&dev->dev.sem); 219 } 220 up_read(&pci_bus_sem); 221 } 222 223 EXPORT_SYMBOL(pci_bus_alloc_resource); 224 EXPORT_SYMBOL_GPL(pci_bus_add_device); 225 EXPORT_SYMBOL(pci_bus_add_devices); 226 EXPORT_SYMBOL(pci_enable_bridges); 227