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