arch/i386/pci/common.c

   1 /*
   2  *      Low-Level PCI Support for PC
   3  *
   4  *      (c) 1999--2000 Martin Mares <mj@ucw.cz>
   5  */
   6
   7 #include <linux/sched.h>
   8 #include <linux/pci.h>
   9 #include <linux/ioport.h>
  10 #include <linux/init.h>
  11 #include <linux/dmi.h>
  12
  13 #include <asm/acpi.h>
  14 #include <asm/segment.h>
  15 #include <asm/io.h>
  16 #include <asm/smp.h>
  17
  18 #include "pci.h"
  19
  20 unsigned int pci_probe = PCI_PROBE_BIOS | PCI_PROBE_CONF1 | PCI_PROBE_CONF2 |
  21                                 PCI_PROBE_MMCONF;
  22
  23 int pci_routeirq;
  24 int pcibios_last_bus = -1;
  25 unsigned long pirq_table_addr;
  26 struct pci_bus *pci_root_bus;
  27 struct pci_raw_ops *raw_pci_ops;
  28
  29 static int pci_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *value)
  30 {
  31         return raw_pci_ops->read(0, bus->number, devfn, where, size, value);
  32 }
  33
  34 static int pci_write(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 value)
  35 {
  36         return raw_pci_ops->write(0, bus->number, devfn, where, size, value);
  37 }
  38
  39 struct pci_ops pci_root_ops = {
  40         .read = pci_read,
  41         .write = pci_write,
  42 };
  43
  44 /*
  45  * legacy, numa, and acpi all want to call pcibios_scan_root
  46  * from their initcalls. This flag prevents that.
  47  */
  48 int pcibios_scanned;
  49
  50 /*
  51  * This interrupt-safe spinlock protects all accesses to PCI
  52  * configuration space.
  53  */
  54 DEFINE_SPINLOCK(pci_config_lock);
  55
  56 /*
  57  * Several buggy motherboards address only 16 devices and mirror
  58  * them to next 16 IDs. We try to detect this `feature' on all
  59  * primary buses (those containing host bridges as they are
  60  * expected to be unique) and remove the ghost devices.
  61  */
  62
  63 static void __devinit pcibios_fixup_ghosts(struct pci_bus *b)
  64 {
  65         struct list_head *ln, *mn;
  66         struct pci_dev *d, *e;
  67         int mirror = PCI_DEVFN(16,0);
  68         int seen_host_bridge = 0;
  69         int i;
  70
  71         DBG("PCI: Scanning for ghost devices on bus %d\n", b->number);
  72         list_for_each(ln, &b->devices) {
  73                 d = pci_dev_b(ln);
  74                 if ((d->class >> 8) == PCI_CLASS_BRIDGE_HOST)
  75                         seen_host_bridge++;
  76                 for (mn=ln->next; mn != &b->devices; mn=mn->next) {
  77                         e = pci_dev_b(mn);
  78                         if (e->devfn != d->devfn + mirror ||
  79                             e->vendor != d->vendor ||
  80                             e->device != d->device ||
  81                             e->class != d->class)
  82                                 continue;
  83                         for(i=0; i<PCI_NUM_RESOURCES; i++)
  84                                 if (e->resource[i].start != d->resource[i].start ||
  85                                     e->resource[i].end != d->resource[i].end ||
  86                                     e->resource[i].flags != d->resource[i].flags)
  87                                         continue;
  88                         break;
  89                 }
  90                 if (mn == &b->devices)
  91                         return;
  92         }
  93         if (!seen_host_bridge)
  94                 return;
  95         printk(KERN_WARNING "PCI: Ignoring ghost devices on bus %02x\n", b->number);
  96
  97         ln = &b->devices;
  98         while (ln->next != &b->devices) {
  99                 d = pci_dev_b(ln->next);
 100                 if (d->devfn >= mirror) {
 101                         list_del(&d->global_list);
 102                         list_del(&d->bus_list);
 103                         kfree(d);
 104                 } else
 105                         ln = ln->next;
 106         }
 107 }
 108
 109 /*
 110  *  Called after each bus is probed, but before its children
 111  *  are examined.
 112  */
 113
 114 void __devinit  pcibios_fixup_bus(struct pci_bus *b)
 115 {
 116         pcibios_fixup_ghosts(b);
 117         pci_read_bridge_bases(b);
 118 }
 119
 120 /*
 121  * Enable renumbering of PCI bus# ranges to reach all PCI busses (Cardbus)
 122  */
 123 #ifdef __i386__
 124 static int __devinit assign_all_busses(struct dmi_system_id *d)
 125 {
 126         pci_probe |= PCI_ASSIGN_ALL_BUSSES;
 127         printk(KERN_INFO "%s detected: enabling PCI bus# renumbering"
 128                         " (pci=assign-busses)\n", d->ident);
 129         return 0;
 130 }
 131 #endif
 132
 133 /*
 134  * Laptops which need pci=assign-busses to see Cardbus cards
 135  */
 136 static struct dmi_system_id __devinitdata pciprobe_dmi_table[] = {
 137 #ifdef __i386__
 138         {
 139                 .callback = assign_all_busses,
 140                 .ident = "Samsung X20 Laptop",
 141                 .matches = {
 142                         DMI_MATCH(DMI_SYS_VENDOR, "Samsung Electronics"),
 143                         DMI_MATCH(DMI_PRODUCT_NAME, "SX20S"),
 144                 },
 145         },
 146 #endif          /* __i386__ */
 147         {}
 148 };
 149
 150 struct pci_bus * __devinit pcibios_scan_root(int busnum)
 151 {
 152         struct pci_bus *bus = NULL;
 153
 154         dmi_check_system(pciprobe_dmi_table);
 155
 156         while ((bus = pci_find_next_bus(bus)) != NULL) {
 157                 if (bus->number == busnum) {
 158                         /* Already scanned */
 159                         return bus;
 160                 }
 161         }
 162
 163         printk(KERN_DEBUG "PCI: Probing PCI hardware (bus %02x)\n", busnum);
 164
 165         return pci_scan_bus_parented(NULL, busnum, &pci_root_ops, NULL);
 166 }
 167
 168 extern u8 pci_cache_line_size;
 169
 170 static int __init pcibios_init(void)
 171 {
 172         struct cpuinfo_x86 *c = &boot_cpu_data;
 173
 174         if (!raw_pci_ops) {
 175                 printk(KERN_WARNING "PCI: System does not support PCI\n");
 176                 return 0;
 177         }
 178
 179         /*
 180          * Assume PCI cacheline size of 32 bytes for all x86s except K7/K8
 181          * and P4. It's also good for 386/486s (which actually have 16)
 182          * as quite a few PCI devices do not support smaller values.
 183          */
 184         pci_cache_line_size = 32 >> 2;
 185         if (c->x86 >= 6 && c->x86_vendor == X86_VENDOR_AMD)
 186                 pci_cache_line_size = 64 >> 2;  /* K7 & K8 */
 187         else if (c->x86 > 6 && c->x86_vendor == X86_VENDOR_INTEL)
 188                 pci_cache_line_size = 128 >> 2; /* P4 */
 189
 190         pcibios_resource_survey();
 191
 192 #ifdef CONFIG_PCI_BIOS
 193         if ((pci_probe & PCI_BIOS_SORT) && !(pci_probe & PCI_NO_SORT))
 194                 pcibios_sort();
 195 #endif
 196         return 0;
 197 }
 198
 199 subsys_initcall(pcibios_init);
 200
 201 char * __devinit  pcibios_setup(char *str)
 202 {
 203         if (!strcmp(str, "off")) {
 204                 pci_probe = 0;
 205                 return NULL;
 206         }
 207 #ifdef CONFIG_PCI_BIOS
 208         else if (!strcmp(str, "bios")) {
 209                 pci_probe = PCI_PROBE_BIOS;
 210                 return NULL;
 211         } else if (!strcmp(str, "nobios")) {
 212                 pci_probe &= ~PCI_PROBE_BIOS;
 213                 return NULL;
 214         } else if (!strcmp(str, "nosort")) {
 215                 pci_probe |= PCI_NO_SORT;
 216                 return NULL;
 217         } else if (!strcmp(str, "biosirq")) {
 218                 pci_probe |= PCI_BIOS_IRQ_SCAN;
 219                 return NULL;
 220         } else if (!strncmp(str, "pirqaddr=", 9)) {
 221                 pirq_table_addr = simple_strtoul(str+9, NULL, 0);
 222                 return NULL;
 223         }
 224 #endif
 225 #ifdef CONFIG_PCI_DIRECT
 226         else if (!strcmp(str, "conf1")) {
 227                 pci_probe = PCI_PROBE_CONF1 | PCI_NO_CHECKS;
 228                 return NULL;
 229         }
 230         else if (!strcmp(str, "conf2")) {
 231                 pci_probe = PCI_PROBE_CONF2 | PCI_NO_CHECKS;
 232                 return NULL;
 233         }
 234 #endif
 235 #ifdef CONFIG_PCI_MMCONFIG
 236         else if (!strcmp(str, "nommconf")) {
 237                 pci_probe &= ~PCI_PROBE_MMCONF;
 238                 return NULL;
 239         }
 240 #endif
 241         else if (!strcmp(str, "noacpi")) {
 242                 acpi_noirq_set();
 243                 return NULL;
 244         }
 245         else if (!strcmp(str, "noearly")) {
 246                 pci_probe |= PCI_PROBE_NOEARLY;
 247                 return NULL;
 248         }
 249 #ifndef CONFIG_X86_VISWS
 250         else if (!strcmp(str, "usepirqmask")) {
 251                 pci_probe |= PCI_USE_PIRQ_MASK;
 252                 return NULL;
 253         } else if (!strncmp(str, "irqmask=", 8)) {
 254                 pcibios_irq_mask = simple_strtol(str+8, NULL, 0);
 255                 return NULL;
 256         } else if (!strncmp(str, "lastbus=", 8)) {
 257                 pcibios_last_bus = simple_strtol(str+8, NULL, 0);
 258                 return NULL;
 259         }
 260 #endif
 261         else if (!strcmp(str, "rom")) {
 262                 pci_probe |= PCI_ASSIGN_ROMS;
 263                 return NULL;
 264         } else if (!strcmp(str, "assign-busses")) {
 265                 pci_probe |= PCI_ASSIGN_ALL_BUSSES;
 266                 return NULL;
 267         } else if (!strcmp(str, "routeirq")) {
 268                 pci_routeirq = 1;
 269                 return NULL;
 270         }
 271         return str;
 272 }
 273
 274 unsigned int pcibios_assign_all_busses(void)
 275 {
 276         return (pci_probe & PCI_ASSIGN_ALL_BUSSES) ? 1 : 0;
 277 }
 278
 279 int pcibios_enable_device(struct pci_dev *dev, int mask)
 280 {
 281         int err;
 282
 283         if ((err = pcibios_enable_resources(dev, mask)) < 0)
 284                 return err;
 285
 286         return pcibios_enable_irq(dev);
 287 }
 288
 289 void pcibios_disable_device (struct pci_dev *dev)
 290 {
 291         pcibios_disable_resources(dev);
 292         if (pcibios_disable_irq)
 293                 pcibios_disable_irq(dev);
 294 }