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 unsigned long size, unsigned long align, unsigned long min, 38 unsigned int type_mask, 39 void (*alignf)(void *, struct resource *, 40 unsigned long, unsigned long), 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 void __devinit pci_bus_add_device(struct pci_dev *dev) 81 { 82 device_add(&dev->dev); 83 84 spin_lock(&pci_bus_lock); 85 list_add_tail(&dev->global_list, &pci_devices); 86 spin_unlock(&pci_bus_lock); 87 88 pci_proc_attach_device(dev); 89 pci_create_sysfs_dev_files(dev); 90 } 91 92 /** 93 * pci_bus_add_devices - insert newly discovered PCI devices 94 * @bus: bus to check for new devices 95 * 96 * Add newly discovered PCI devices (which are on the bus->devices 97 * list) to the global PCI device list, add the sysfs and procfs 98 * entries. Where a bridge is found, add the discovered bus to 99 * the parents list of child buses, and recurse (breadth-first 100 * to be compatible with 2.4) 101 * 102 * Call hotplug for each new devices. 103 */ 104 void __devinit pci_bus_add_devices(struct pci_bus *bus) 105 { 106 struct pci_dev *dev; 107 108 list_for_each_entry(dev, &bus->devices, bus_list) { 109 /* 110 * Skip already-present devices (which are on the 111 * global device list.) 112 */ 113 if (!list_empty(&dev->global_list)) 114 continue; 115 pci_bus_add_device(dev); 116 } 117 118 list_for_each_entry(dev, &bus->devices, bus_list) { 119 120 BUG_ON(list_empty(&dev->global_list)); 121 122 /* 123 * If there is an unattached subordinate bus, attach 124 * it and then scan for unattached PCI devices. 125 */ 126 if (dev->subordinate) { 127 if (list_empty(&dev->subordinate->node)) { 128 spin_lock(&pci_bus_lock); 129 list_add_tail(&dev->subordinate->node, 130 &dev->bus->children); 131 spin_unlock(&pci_bus_lock); 132 } 133 pci_bus_add_devices(dev->subordinate); 134 135 sysfs_create_link(&dev->subordinate->class_dev.kobj, &dev->dev.kobj, "bridge"); 136 } 137 } 138 } 139 140 void pci_enable_bridges(struct pci_bus *bus) 141 { 142 struct pci_dev *dev; 143 int retval; 144 145 list_for_each_entry(dev, &bus->devices, bus_list) { 146 if (dev->subordinate) { 147 retval = pci_enable_device(dev); 148 pci_set_master(dev); 149 pci_enable_bridges(dev->subordinate); 150 } 151 } 152 } 153 154 /** pci_walk_bus - walk devices on/under bus, calling callback. 155 * @top bus whose devices should be walked 156 * @cb callback to be called for each device found 157 * @userdata arbitrary pointer to be passed to callback. 158 * 159 * Walk the given bus, including any bridged devices 160 * on buses under this bus. Call the provided callback 161 * on each device found. 162 */ 163 void pci_walk_bus(struct pci_bus *top, void (*cb)(struct pci_dev *, void *), 164 void *userdata) 165 { 166 struct pci_dev *dev; 167 struct pci_bus *bus; 168 struct list_head *next; 169 170 bus = top; 171 spin_lock(&pci_bus_lock); 172 next = top->devices.next; 173 for (;;) { 174 if (next == &bus->devices) { 175 /* end of this bus, go up or finish */ 176 if (bus == top) 177 break; 178 next = bus->self->bus_list.next; 179 bus = bus->self->bus; 180 continue; 181 } 182 dev = list_entry(next, struct pci_dev, bus_list); 183 pci_dev_get(dev); 184 if (dev->subordinate) { 185 /* this is a pci-pci bridge, do its devices next */ 186 next = dev->subordinate->devices.next; 187 bus = dev->subordinate; 188 } else 189 next = dev->bus_list.next; 190 spin_unlock(&pci_bus_lock); 191 192 /* Run device routines with the bus unlocked */ 193 cb(dev, userdata); 194 195 spin_lock(&pci_bus_lock); 196 pci_dev_put(dev); 197 } 198 spin_unlock(&pci_bus_lock); 199 } 200 EXPORT_SYMBOL_GPL(pci_walk_bus); 201 202 EXPORT_SYMBOL(pci_bus_alloc_resource); 203 EXPORT_SYMBOL_GPL(pci_bus_add_device); 204 EXPORT_SYMBOL(pci_bus_add_devices); 205 EXPORT_SYMBOL(pci_enable_bridges); 206