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 static int pci_bf_sort;
  24 int pci_routeirq;
  25 int pcibios_last_bus = -1;
  26 unsigned long pirq_table_addr;
  27 struct pci_bus *pci_root_bus;
  28 struct pci_raw_ops *raw_pci_ops;
  29
  30 static int pci_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *value)
  31 {
  32         return raw_pci_ops->read(0, bus->number, devfn, where, size, value);
  33 }
  34
  35 static int pci_write(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 value)
  36 {
  37         return raw_pci_ops->write(0, bus->number, devfn, where, size, value);
  38 }
  39
  40 struct pci_ops pci_root_ops = {
  41         .read = pci_read,
  42         .write = pci_write,
  43 };
  44
  45 /*
  46  * legacy, numa, and acpi all want to call pcibios_scan_root
  47  * from their initcalls. This flag prevents that.
  48  */
  49 int pcibios_scanned;
  50
  51 /*
  52  * This interrupt-safe spinlock protects all accesses to PCI
  53  * configuration space.
  54  */
  55 DEFINE_SPINLOCK(pci_config_lock);
  56
  57 /*
  58  * Several buggy motherboards address only 16 devices and mirror
  59  * them to next 16 IDs. We try to detect this `feature' on all
  60  * primary buses (those containing host bridges as they are
  61  * expected to be unique) and remove the ghost devices.
  62  */
  63
  64 static void __devinit pcibios_fixup_ghosts(struct pci_bus *b)
  65 {
  66         struct list_head *ln, *mn;
  67         struct pci_dev *d, *e;
  68         int mirror = PCI_DEVFN(16,0);
  69         int seen_host_bridge = 0;
  70         int i;
  71
  72         DBG("PCI: Scanning for ghost devices on bus %d\n", b->number);
  73         list_for_each(ln, &b->devices) {
  74                 d = pci_dev_b(ln);
  75                 if ((d->class >> 8) == PCI_CLASS_BRIDGE_HOST)
  76                         seen_host_bridge++;
  77                 for (mn=ln->next; mn != &b->devices; mn=mn->next) {
  78                         e = pci_dev_b(mn);
  79                         if (e->devfn != d->devfn + mirror ||
  80                             e->vendor != d->vendor ||
  81                             e->device != d->device ||
  82                             e->class != d->class)
  83                                 continue;
  84                         for(i=0; i<PCI_NUM_RESOURCES; i++)
  85                                 if (e->resource[i].start != d->resource[i].start ||
  86                                     e->resource[i].end != d->resource[i].end ||
  87                                     e->resource[i].flags != d->resource[i].flags)
  88                                         continue;
  89                         break;
  90                 }
  91                 if (mn == &b->devices)
  92                         return;
  93         }
  94         if (!seen_host_bridge)
  95                 return;
  96         printk(KERN_WARNING "PCI: Ignoring ghost devices on bus %02x\n", b->number);
  97
  98         ln = &b->devices;
  99         while (ln->next != &b->devices) {
 100                 d = pci_dev_b(ln->next);
 101                 if (d->devfn >= mirror) {
 102                         list_del(&d->global_list);
 103                         list_del(&d->bus_list);
 104                         kfree(d);
 105                 } else
 106                         ln = ln->next;
 107         }
 108 }
 109
 110 /*
 111  *  Called after each bus is probed, but before its children
 112  *  are examined.
 113  */
 114
 115 void __devinit  pcibios_fixup_bus(struct pci_bus *b)
 116 {
 117         pcibios_fixup_ghosts(b);
 118         pci_read_bridge_bases(b);
 119 }
 120
 121 /*
 122  * Only use DMI information to set this if nothing was passed
 123  * on the kernel command line (which was parsed earlier).
 124  */
 125
 126 static int __devinit set_bf_sort(struct dmi_system_id *d)
 127 {
 128         if (pci_bf_sort == pci_bf_sort_default) {
 129                 pci_bf_sort = pci_dmi_bf;
 130                 printk(KERN_INFO "PCI: %s detected, enabling pci=bfsort.\n", d->ident);
 131         }
 132         return 0;
 133 }
 134
 135 /*
 136  * Enable renumbering of PCI bus# ranges to reach all PCI busses (Cardbus)
 137  */
 138 #ifdef __i386__
 139 static int __devinit assign_all_busses(struct dmi_system_id *d)
 140 {
 141         pci_probe |= PCI_ASSIGN_ALL_BUSSES;
 142         printk(KERN_INFO "%s detected: enabling PCI bus# renumbering"
 143                         " (pci=assign-busses)\n", d->ident);
 144         return 0;
 145 }
 146 #endif
 147
 148 static struct dmi_system_id __devinitdata pciprobe_dmi_table[] = {
 149 #ifdef __i386__
 150 /*
 151  * Laptops which need pci=assign-busses to see Cardbus cards
 152  */
 153         {
 154                 .callback = assign_all_busses,
 155                 .ident = "Samsung X20 Laptop",
 156                 .matches = {
 157                         DMI_MATCH(DMI_SYS_VENDOR, "Samsung Electronics"),
 158                         DMI_MATCH(DMI_PRODUCT_NAME, "SX20S"),
 159                 },
 160         },
 161 #endif          /* __i386__ */
 162         {
 163                 .callback = set_bf_sort,
 164                 .ident = "Dell PowerEdge 1950",
 165                 .matches = {
 166                         DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
 167                         DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1950"),
 168                 },
 169         },
 170         {
 171                 .callback = set_bf_sort,
 172                 .ident = "Dell PowerEdge 1955",
 173                 .matches = {
 174                         DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
 175                         DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1955"),
 176                 },
 177         },
 178         {
 179                 .callback = set_bf_sort,
 180                 .ident = "Dell PowerEdge 2900",
 181                 .matches = {
 182                         DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
 183                         DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2900"),
 184                 },
 185         },
 186         {
 187                 .callback = set_bf_sort,
 188                 .ident = "Dell PowerEdge 2950",
 189                 .matches = {
 190                         DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
 191                         DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2950"),
 192                 },
 193         },
 194         {}
 195 };
 196
 197 struct pci_bus * __devinit pcibios_scan_root(int busnum)
 198 {
 199         struct pci_bus *bus = NULL;
 200
 201         dmi_check_system(pciprobe_dmi_table);
 202
 203         while ((bus = pci_find_next_bus(bus)) != NULL) {
 204                 if (bus->number == busnum) {
 205                         /* Already scanned */
 206                         return bus;
 207                 }
 208         }
 209
 210         printk(KERN_DEBUG "PCI: Probing PCI hardware (bus %02x)\n", busnum);
 211
 212         return pci_scan_bus_parented(NULL, busnum, &pci_root_ops, NULL);
 213 }
 214
 215 extern u8 pci_cache_line_size;
 216
 217 static int __init pcibios_init(void)
 218 {
 219         struct cpuinfo_x86 *c = &boot_cpu_data;
 220
 221         if (!raw_pci_ops) {
 222                 printk(KERN_WARNING "PCI: System does not support PCI\n");
 223                 return 0;
 224         }
 225
 226         /*
 227          * Assume PCI cacheline size of 32 bytes for all x86s except K7/K8
 228          * and P4. It's also good for 386/486s (which actually have 16)
 229          * as quite a few PCI devices do not support smaller values.
 230          */
 231         pci_cache_line_size = 32 >> 2;
 232         if (c->x86 >= 6 && c->x86_vendor == X86_VENDOR_AMD)
 233                 pci_cache_line_size = 64 >> 2;  /* K7 & K8 */
 234         else if (c->x86 > 6 && c->x86_vendor == X86_VENDOR_INTEL)
 235                 pci_cache_line_size = 128 >> 2; /* P4 */
 236
 237         pcibios_resource_survey();
 238
 239         if (pci_bf_sort >= pci_force_bf)
 240                 pci_sort_breadthfirst();
 241 #ifdef CONFIG_PCI_BIOS
 242         if ((pci_probe & PCI_BIOS_SORT) && !(pci_probe & PCI_NO_SORT))
 243                 pcibios_sort();
 244 #endif
 245         return 0;
 246 }
 247
 248 subsys_initcall(pcibios_init);
 249
 250 char * __devinit  pcibios_setup(char *str)
 251 {
 252         if (!strcmp(str, "off")) {
 253                 pci_probe = 0;
 254                 return NULL;
 255         } else if (!strcmp(str, "bfsort")) {
 256                 pci_bf_sort = pci_force_bf;
 257                 return NULL;
 258         } else if (!strcmp(str, "nobfsort")) {
 259                 pci_bf_sort = pci_force_nobf;
 260                 return NULL;
 261         }
 262 #ifdef CONFIG_PCI_BIOS
 263         else if (!strcmp(str, "bios")) {
 264                 pci_probe = PCI_PROBE_BIOS;
 265                 return NULL;
 266         } else if (!strcmp(str, "nobios")) {
 267                 pci_probe &= ~PCI_PROBE_BIOS;
 268                 return NULL;
 269         } else if (!strcmp(str, "nosort")) {
 270                 pci_probe |= PCI_NO_SORT;
 271                 return NULL;
 272         } else if (!strcmp(str, "biosirq")) {
 273                 pci_probe |= PCI_BIOS_IRQ_SCAN;
 274                 return NULL;
 275         } else if (!strncmp(str, "pirqaddr=", 9)) {
 276                 pirq_table_addr = simple_strtoul(str+9, NULL, 0);
 277                 return NULL;
 278         }
 279 #endif
 280 #ifdef CONFIG_PCI_DIRECT
 281         else if (!strcmp(str, "conf1")) {
 282                 pci_probe = PCI_PROBE_CONF1 | PCI_NO_CHECKS;
 283                 return NULL;
 284         }
 285         else if (!strcmp(str, "conf2")) {
 286                 pci_probe = PCI_PROBE_CONF2 | PCI_NO_CHECKS;
 287                 return NULL;
 288         }
 289 #endif
 290 #ifdef CONFIG_PCI_MMCONFIG
 291         else if (!strcmp(str, "nommconf")) {
 292                 pci_probe &= ~PCI_PROBE_MMCONF;
 293                 return NULL;
 294         }
 295 #endif
 296         else if (!strcmp(str, "noacpi")) {
 297                 acpi_noirq_set();
 298                 return NULL;
 299         }
 300         else if (!strcmp(str, "noearly")) {
 301                 pci_probe |= PCI_PROBE_NOEARLY;
 302                 return NULL;
 303         }
 304 #ifndef CONFIG_X86_VISWS
 305         else if (!strcmp(str, "usepirqmask")) {
 306                 pci_probe |= PCI_USE_PIRQ_MASK;
 307                 return NULL;
 308         } else if (!strncmp(str, "irqmask=", 8)) {
 309                 pcibios_irq_mask = simple_strtol(str+8, NULL, 0);
 310                 return NULL;
 311         } else if (!strncmp(str, "lastbus=", 8)) {
 312                 pcibios_last_bus = simple_strtol(str+8, NULL, 0);
 313                 return NULL;
 314         }
 315 #endif
 316         else if (!strcmp(str, "rom")) {
 317                 pci_probe |= PCI_ASSIGN_ROMS;
 318                 return NULL;
 319         } else if (!strcmp(str, "assign-busses")) {
 320                 pci_probe |= PCI_ASSIGN_ALL_BUSSES;
 321                 return NULL;
 322         } else if (!strcmp(str, "routeirq")) {
 323                 pci_routeirq = 1;
 324                 return NULL;
 325         }
 326         return str;
 327 }
 328
 329 unsigned int pcibios_assign_all_busses(void)
 330 {
 331         return (pci_probe & PCI_ASSIGN_ALL_BUSSES) ? 1 : 0;
 332 }
 333
 334 int pcibios_enable_device(struct pci_dev *dev, int mask)
 335 {
 336         int err;
 337
 338         if ((err = pcibios_enable_resources(dev, mask)) < 0)
 339                 return err;
 340
 341         return pcibios_enable_irq(dev);
 342 }
 343
 344 void pcibios_disable_device (struct pci_dev *dev)
 345 {
 346         if (pcibios_disable_irq)
 347                 pcibios_disable_irq(dev);
 348 }