drivers/pci/bus.c

   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, min, -1, align,
  64                                         alignf, alignf_data);
  65                 if (ret == 0)
  66                         break;
  67         }
  68         return ret;
  69 }
  70
  71 /**
  72  * add a single device
  73  * @dev: device to add
  74  *
  75  * This adds a single pci device to the global
  76  * device list and adds sysfs and procfs entries
  77  */
  78 void __devinit pci_bus_add_device(struct pci_dev *dev)
  79 {
  80         device_add(&dev->dev);
  81
  82         spin_lock(&pci_bus_lock);
  83         list_add_tail(&dev->global_list, &pci_devices);
  84         spin_unlock(&pci_bus_lock);
  85
  86         pci_proc_attach_device(dev);
  87         pci_create_sysfs_dev_files(dev);
  88 }
  89
  90 /**
  91  * pci_bus_add_devices - insert newly discovered PCI devices
  92  * @bus: bus to check for new devices
  93  *
  94  * Add newly discovered PCI devices (which are on the bus->devices
  95  * list) to the global PCI device list, add the sysfs and procfs
  96  * entries.  Where a bridge is found, add the discovered bus to
  97  * the parents list of child buses, and recurse (breadth-first
  98  * to be compatible with 2.4)
  99  *
 100  * Call hotplug for each new devices.
 101  */
 102 void __devinit pci_bus_add_devices(struct pci_bus *bus)
 103 {
 104         struct pci_dev *dev;
 105
 106         list_for_each_entry(dev, &bus->devices, bus_list) {
 107                 /*
 108                  * Skip already-present devices (which are on the
 109                  * global device list.)
 110                  */
 111                 if (!list_empty(&dev->global_list))
 112                         continue;
 113                 pci_bus_add_device(dev);
 114         }
 115
 116         list_for_each_entry(dev, &bus->devices, bus_list) {
 117
 118                 BUG_ON(list_empty(&dev->global_list));
 119
 120                 /*
 121                  * If there is an unattached subordinate bus, attach
 122                  * it and then scan for unattached PCI devices.
 123                  */
 124                 if (dev->subordinate) {
 125                        if (list_empty(&dev->subordinate->node)) {
 126                                spin_lock(&pci_bus_lock);
 127                                list_add_tail(&dev->subordinate->node,
 128                                                &dev->bus->children);
 129                                spin_unlock(&pci_bus_lock);
 130                        }
 131                         pci_bus_add_devices(dev->subordinate);
 132
 133                         sysfs_create_link(&dev->subordinate->class_dev.kobj, &dev->dev.kobj, "bridge");
 134                 }
 135         }
 136 }
 137
 138 void pci_enable_bridges(struct pci_bus *bus)
 139 {
 140         struct pci_dev *dev;
 141
 142         list_for_each_entry(dev, &bus->devices, bus_list) {
 143                 if (dev->subordinate) {
 144                         pci_enable_device(dev);
 145                         pci_set_master(dev);
 146                         pci_enable_bridges(dev->subordinate);
 147                 }
 148         }
 149 }
 150
 151 EXPORT_SYMBOL(pci_bus_alloc_resource);
 152 EXPORT_SYMBOL_GPL(pci_bus_add_device);
 153 EXPORT_SYMBOL(pci_bus_add_devices);
 154 EXPORT_SYMBOL(pci_enable_bridges);