arch/x86_64/pci/common.c

   1 /*
   2  *      Low-Level PCI Support for PC
   3  *
   4  *      (c) 1999--2000 Martin Mares <mj@ucw.cz>
   5
   6  Note: on x86-64 there is no PCI BIOS so there is no way to sort in the
   7  same order as 32bit Linux. This could cause grief for dualbooting because
   8  devices may wander.  May want to use ACPI for sorting eventually.
   9
  10  */
  11
  12 #include <linux/sched.h>
  13 #include <linux/pci.h>
  14 #include <linux/init.h>
  15 #include <linux/ioport.h>
  16
  17 #include <asm/segment.h>
  18 #include <asm/io.h>
  19 #include <asm/smp.h>
  20 #include <asm/cache.h>
  21
  22 #include "pci.h"
  23
  24 unsigned int pci_probe = PCI_PROBE_CONF1 | PCI_PROBE_CONF2;
  25
  26 int pcibios_last_bus = 0xff; /* XXX */
  27 struct pci_bus *pci_root_bus = NULL;
  28 struct pci_ops *pci_root_ops = NULL;
  29
  30 int (*pci_config_read)(int seg, int bus, int dev, int fn, int reg, int len, u32 *value) = NULL;
  31 int (*pci_config_write)(int seg, int bus, int dev, int fn, int reg, int len, u32 value) = NULL;
  32
  33 /*
  34  * legacy, numa, and acpi all want to call pcibios_scan_root
  35  * from their initcalls. This flag prevents that.
  36  */
  37 int pcibios_scanned;
  38
  39 /*
  40  * This interrupt-safe spinlock protects all accesses to PCI
  41  * configuration space.
  42  */
  43 spinlock_t pci_config_lock = SPIN_LOCK_UNLOCKED;
  44
  45 /*
  46  * Several buggy motherboards address only 16 devices and mirror
  47  * them to next 16 IDs. We try to detect this `feature' on all
  48  * primary buses (those containing host bridges as they are
  49  * expected to be unique) and remove the ghost devices.
  50  */
  51
  52 static void __devinit pcibios_fixup_ghosts(struct pci_bus *b)
  53 {
  54         struct list_head *ln, *mn;
  55         struct pci_dev *d, *e;
  56         int mirror = PCI_DEVFN(16,0);
  57         int seen_host_bridge = 0;
  58         int i;
  59
  60         DBG("PCI: Scanning for ghost devices on bus %d\n", b->number);
  61         for (ln=b->devices.next; ln != &b->devices; ln=ln->next) {
  62                 d = pci_dev_b(ln);
  63                 if ((d->class >> 8) == PCI_CLASS_BRIDGE_HOST)
  64                         seen_host_bridge++;
  65                 for (mn=ln->next; mn != &b->devices; mn=mn->next) {
  66                         e = pci_dev_b(mn);
  67                         if (e->devfn != d->devfn + mirror ||
  68                             e->vendor != d->vendor ||
  69                             e->device != d->device ||
  70                             e->class != d->class)
  71                                 continue;
  72                         for(i=0; i<PCI_NUM_RESOURCES; i++)
  73                                 if (e->resource[i].start != d->resource[i].start ||
  74                                     e->resource[i].end != d->resource[i].end ||
  75                                     e->resource[i].flags != d->resource[i].flags)
  76                                         continue;
  77                         break;
  78                 }
  79                 if (mn == &b->devices)
  80                         return;
  81         }
  82         if (!seen_host_bridge)
  83                 return;
  84         printk(KERN_WARNING "PCI: Ignoring ghost devices on bus %02x\n", b->number);
  85
  86         ln = &b->devices;
  87         while (ln->next != &b->devices) {
  88                 d = pci_dev_b(ln->next);
  89                 if (d->devfn >= mirror) {
  90                         list_del(&d->global_list);
  91                         list_del(&d->bus_list);
  92                         kfree(d);
  93                 } else
  94                         ln = ln->next;
  95         }
  96 }
  97
  98 struct pbus_set_ranges_data;
  99
 100 void __devinit
 101 pcibios_fixup_pbus_ranges (struct pci_bus *bus, struct pbus_set_ranges_data *ranges)
 102 {
 103 }
 104
 105 /*
 106  *  Called after each bus is probed, but before its children
 107  *  are examined.
 108  */
 109
 110 void __devinit  pcibios_fixup_bus(struct pci_bus *b)
 111 {
 112         pcibios_fixup_ghosts(b);
 113         pci_read_bridge_bases(b);
 114 }
 115
 116
 117 struct pci_bus * __devinit pcibios_scan_root(int busnum)
 118 {
 119         struct list_head *list;
 120         struct pci_bus *bus;
 121
 122         list_for_each(list, &pci_root_buses) {
 123                 bus = pci_bus_b(list);
 124                 if (bus->number == busnum) {
 125                         /* Already scanned */
 126                         return bus;
 127                 }
 128         }
 129
 130         printk("PCI: Probing PCI hardware (bus %02x)\n", busnum);
 131
 132         return pci_scan_bus(busnum, pci_root_ops, NULL);
 133 }
 134
 135 extern u8 pci_cache_line_size;
 136
 137 static int __init pcibios_init(void)
 138 {
 139         if (!pci_root_ops) {
 140                 printk("PCI: System does not support PCI\n");
 141                 return 0;
 142         }
 143
 144         pci_cache_line_size = boot_cpu_data.x86_clflush_size >> 2;
 145
 146         pcibios_resource_survey();
 147
 148 #ifdef CONFIG_GART_IOMMU
 149         pci_iommu_init();
 150 #endif
 151
 152         /* may eventually need to do ACPI sort here. */
 153         return 0;
 154 }
 155
 156 subsys_initcall(pcibios_init);
 157
 158 char * __devinit  pcibios_setup(char *str)
 159 {
 160         if (!strcmp(str, "off")) {
 161                 pci_probe = 0;
 162                 return NULL;
 163         }
 164 #ifdef CONFIG_PCI_DIRECT
 165         else if (!strcmp(str, "conf1")) {
 166                 pci_probe = PCI_PROBE_CONF1 | PCI_NO_CHECKS;
 167                 return NULL;
 168         }
 169         else if (!strcmp(str, "conf2")) {
 170                 pci_probe = PCI_PROBE_CONF2 | PCI_NO_CHECKS;
 171                 return NULL;
 172         }
 173 #endif
 174 #ifdef CONFIG_ACPI_PCI
 175         else if (!strcmp(str, "noacpi")) {
 176                 pci_probe |= PCI_NO_ACPI_ROUTING;
 177                 return NULL;
 178         }
 179 #endif
 180         else if (!strcmp(str, "rom")) {
 181                 pci_probe |= PCI_ASSIGN_ROMS;
 182                 return NULL;
 183         } else if (!strcmp(str, "assign-busses")) {
 184                 pci_probe |= PCI_ASSIGN_ALL_BUSSES;
 185                 return NULL;
 186         } else if (!strcmp(str, "usepirqmask")) {
 187                 pci_probe |= PCI_USE_PIRQ_MASK;
 188                 return NULL;
 189         } else if (!strncmp(str, "irqmask=", 8)) {
 190                 pcibios_irq_mask = simple_strtol(str+8, NULL, 0);
 191                 return NULL;
 192         } else if (!strncmp(str, "lastbus=", 8)) {
 193                 pcibios_last_bus = simple_strtol(str+8, NULL, 0);
 194                 return NULL;
 195         }
 196         return str;
 197 }
 198
 199 unsigned int pcibios_assign_all_busses(void)
 200 {
 201         return (pci_probe & PCI_ASSIGN_ALL_BUSSES) ? 1 : 0;
 202 }
 203
 204 int pcibios_enable_device(struct pci_dev *dev, int mask)
 205 {
 206         int err;
 207
 208         if ((err = pcibios_enable_resources(dev, mask)) < 0)
 209                 return err;
 210
 211         return pcibios_enable_irq(dev);
 212 }