drivers/acpi/pci_root.c

   1 /*
   2  *  pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
   3  *
   4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   6  *
   7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License as published by
  11  *  the Free Software Foundation; either version 2 of the License, or (at
  12  *  your option) any later version.
  13  *
  14  *  This program is distributed in the hope that it will be useful, but
  15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  *  General Public License for more details.
  18  *
  19  *  You should have received a copy of the GNU General Public License along
  20  *  with this program; if not, write to the Free Software Foundation, Inc.,
  21  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  22  *
  23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  24  */
  25
  26 #include <linux/kernel.h>
  27 #include <linux/module.h>
  28 #include <linux/init.h>
  29 #include <linux/types.h>
  30 #include <linux/proc_fs.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/pm.h>
  33 #include <linux/pci.h>
  34 #include <linux/acpi.h>
  35 #include <acpi/acpi_bus.h>
  36 #include <acpi/acpi_drivers.h>
  37
  38 #define _COMPONENT              ACPI_PCI_COMPONENT
  39 ACPI_MODULE_NAME("pci_root");
  40 #define ACPI_PCI_ROOT_CLASS             "pci_bridge"
  41 #define ACPI_PCI_ROOT_DEVICE_NAME       "PCI Root Bridge"
  42 static int acpi_pci_root_add(struct acpi_device *device);
  43 static int acpi_pci_root_remove(struct acpi_device *device, int type);
  44 static int acpi_pci_root_start(struct acpi_device *device);
  45
  46 static struct acpi_device_id root_device_ids[] = {
  47         {"PNP0A03", 0},
  48         {"", 0},
  49 };
  50 MODULE_DEVICE_TABLE(acpi, root_device_ids);
  51
  52 static struct acpi_driver acpi_pci_root_driver = {
  53         .name = "pci_root",
  54         .class = ACPI_PCI_ROOT_CLASS,
  55         .ids = root_device_ids,
  56         .ops = {
  57                 .add = acpi_pci_root_add,
  58                 .remove = acpi_pci_root_remove,
  59                 .start = acpi_pci_root_start,
  60                 },
  61 };
  62
  63 struct acpi_pci_root {
  64         struct list_head node;
  65         struct acpi_device * device;
  66         struct acpi_pci_id id;
  67         struct pci_bus *bus;
  68 };
  69
  70 static LIST_HEAD(acpi_pci_roots);
  71
  72 static struct acpi_pci_driver *sub_driver;
  73
  74 int acpi_pci_register_driver(struct acpi_pci_driver *driver)
  75 {
  76         int n = 0;
  77         struct list_head *entry;
  78
  79         struct acpi_pci_driver **pptr = &sub_driver;
  80         while (*pptr)
  81                 pptr = &(*pptr)->next;
  82         *pptr = driver;
  83
  84         if (!driver->add)
  85                 return 0;
  86
  87         list_for_each(entry, &acpi_pci_roots) {
  88                 struct acpi_pci_root *root;
  89                 root = list_entry(entry, struct acpi_pci_root, node);
  90                 driver->add(root->device->handle);
  91                 n++;
  92         }
  93
  94         return n;
  95 }
  96
  97 EXPORT_SYMBOL(acpi_pci_register_driver);
  98
  99 void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
 100 {
 101         struct list_head *entry;
 102
 103         struct acpi_pci_driver **pptr = &sub_driver;
 104         while (*pptr) {
 105                 if (*pptr == driver)
 106                         break;
 107                 pptr = &(*pptr)->next;
 108         }
 109         BUG_ON(!*pptr);
 110         *pptr = (*pptr)->next;
 111
 112         if (!driver->remove)
 113                 return;
 114
 115         list_for_each(entry, &acpi_pci_roots) {
 116                 struct acpi_pci_root *root;
 117                 root = list_entry(entry, struct acpi_pci_root, node);
 118                 driver->remove(root->device->handle);
 119         }
 120 }
 121
 122 EXPORT_SYMBOL(acpi_pci_unregister_driver);
 123
 124 acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
 125 {
 126         struct acpi_pci_root *tmp;
 127
 128         list_for_each_entry(tmp, &acpi_pci_roots, node) {
 129                 if ((tmp->id.segment == (u16) seg) && (tmp->id.bus == (u16) bus))
 130                         return tmp->device->handle;
 131         }
 132         return NULL;
 133 }
 134
 135 EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
 136
 137 static acpi_status
 138 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
 139 {
 140         int *busnr = data;
 141         struct acpi_resource_address64 address;
 142
 143         if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
 144             resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
 145             resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
 146                 return AE_OK;
 147
 148         acpi_resource_to_address64(resource, &address);
 149         if ((address.address_length > 0) &&
 150             (address.resource_type == ACPI_BUS_NUMBER_RANGE))
 151                 *busnr = address.minimum;
 152
 153         return AE_OK;
 154 }
 155
 156 static acpi_status try_get_root_bridge_busnr(acpi_handle handle, int *busnum)
 157 {
 158         acpi_status status;
 159
 160         *busnum = -1;
 161         status =
 162             acpi_walk_resources(handle, METHOD_NAME__CRS,
 163                                 get_root_bridge_busnr_callback, busnum);
 164         if (ACPI_FAILURE(status))
 165                 return status;
 166         /* Check if we really get a bus number from _CRS */
 167         if (*busnum == -1)
 168                 return AE_ERROR;
 169         return AE_OK;
 170 }
 171
 172 static void acpi_pci_bridge_scan(struct acpi_device *device)
 173 {
 174         int status;
 175         struct acpi_device *child = NULL;
 176
 177         if (device->flags.bus_address)
 178                 if (device->parent && device->parent->ops.bind) {
 179                         status = device->parent->ops.bind(device);
 180                         if (!status) {
 181                                 list_for_each_entry(child, &device->children, node)
 182                                         acpi_pci_bridge_scan(child);
 183                         }
 184                 }
 185 }
 186
 187 static int acpi_pci_root_add(struct acpi_device *device)
 188 {
 189         int result = 0;
 190         struct acpi_pci_root *root = NULL;
 191         struct acpi_pci_root *tmp;
 192         acpi_status status = AE_OK;
 193         unsigned long value = 0;
 194         acpi_handle handle = NULL;
 195         struct acpi_device *child;
 196
 197
 198         if (!device)
 199                 return -EINVAL;
 200
 201         root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 202         if (!root)
 203                 return -ENOMEM;
 204         INIT_LIST_HEAD(&root->node);
 205
 206         root->device = device;
 207         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 208         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 209         acpi_driver_data(device) = root;
 210
 211         device->ops.bind = acpi_pci_bind;
 212
 213         /*
 214          * Segment
 215          * -------
 216          * Obtained via _SEG, if exists, otherwise assumed to be zero (0).
 217          */
 218         status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
 219                                        &value);
 220         switch (status) {
 221         case AE_OK:
 222                 root->id.segment = (u16) value;
 223                 break;
 224         case AE_NOT_FOUND:
 225                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 226                                   "Assuming segment 0 (no _SEG)\n"));
 227                 root->id.segment = 0;
 228                 break;
 229         default:
 230                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SEG"));
 231                 result = -ENODEV;
 232                 goto end;
 233         }
 234
 235         /*
 236          * Bus
 237          * ---
 238          * Obtained via _BBN, if exists, otherwise assumed to be zero (0).
 239          */
 240         status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN, NULL,
 241                                        &value);
 242         switch (status) {
 243         case AE_OK:
 244                 root->id.bus = (u16) value;
 245                 break;
 246         case AE_NOT_FOUND:
 247                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Assuming bus 0 (no _BBN)\n"));
 248                 root->id.bus = 0;
 249                 break;
 250         default:
 251                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BBN"));
 252                 result = -ENODEV;
 253                 goto end;
 254         }
 255
 256         /* Some systems have wrong _BBN */
 257         list_for_each_entry(tmp, &acpi_pci_roots, node) {
 258                 if ((tmp->id.segment == root->id.segment)
 259                     && (tmp->id.bus == root->id.bus)) {
 260                         int bus = 0;
 261                         acpi_status status;
 262
 263                         printk(KERN_ERR PREFIX
 264                                     "Wrong _BBN value, reboot"
 265                                     " and use option 'pci=noacpi'\n");
 266
 267                         status = try_get_root_bridge_busnr(device->handle, &bus);
 268                         if (ACPI_FAILURE(status))
 269                                 break;
 270                         if (bus != root->id.bus) {
 271                                 printk(KERN_INFO PREFIX
 272                                        "PCI _CRS %d overrides _BBN 0\n", bus);
 273                                 root->id.bus = bus;
 274                         }
 275                         break;
 276                 }
 277         }
 278         /*
 279          * Device & Function
 280          * -----------------
 281          * Obtained from _ADR (which has already been evaluated for us).
 282          */
 283         root->id.device = device->pnp.bus_address >> 16;
 284         root->id.function = device->pnp.bus_address & 0xFFFF;
 285
 286         /*
 287          * TBD: Need PCI interface for enumeration/configuration of roots.
 288          */
 289
 290         /* TBD: Locking */
 291         list_add_tail(&root->node, &acpi_pci_roots);
 292
 293         printk(KERN_INFO PREFIX "%s [%s] (%04x:%02x)\n",
 294                acpi_device_name(device), acpi_device_bid(device),
 295                root->id.segment, root->id.bus);
 296
 297         /*
 298          * Scan the Root Bridge
 299          * --------------------
 300          * Must do this prior to any attempt to bind the root device, as the
 301          * PCI namespace does not get created until this call is made (and
 302          * thus the root bridge's pci_dev does not exist).
 303          */
 304         root->bus = pci_acpi_scan_root(device, root->id.segment, root->id.bus);
 305         if (!root->bus) {
 306                 printk(KERN_ERR PREFIX
 307                             "Bus %04x:%02x not present in PCI namespace\n",
 308                             root->id.segment, root->id.bus);
 309                 result = -ENODEV;
 310                 goto end;
 311         }
 312
 313         /*
 314          * Attach ACPI-PCI Context
 315          * -----------------------
 316          * Thus binding the ACPI and PCI devices.
 317          */
 318         result = acpi_pci_bind_root(device, &root->id, root->bus);
 319         if (result)
 320                 goto end;
 321
 322         /*
 323          * PCI Routing Table
 324          * -----------------
 325          * Evaluate and parse _PRT, if exists.
 326          */
 327         status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
 328         if (ACPI_SUCCESS(status))
 329                 result = acpi_pci_irq_add_prt(device->handle, root->id.segment,
 330                                               root->id.bus);
 331
 332         /*
 333          * Scan and bind all _ADR-Based Devices
 334          */
 335         list_for_each_entry(child, &device->children, node)
 336                 acpi_pci_bridge_scan(child);
 337
 338       end:
 339         if (result) {
 340                 if (!list_empty(&root->node))
 341                         list_del(&root->node);
 342                 kfree(root);
 343         }
 344
 345         return result;
 346 }
 347
 348 static int acpi_pci_root_start(struct acpi_device *device)
 349 {
 350         struct acpi_pci_root *root;
 351
 352
 353         list_for_each_entry(root, &acpi_pci_roots, node) {
 354                 if (root->device == device) {
 355                         pci_bus_add_devices(root->bus);
 356                         return 0;
 357                 }
 358         }
 359         return -ENODEV;
 360 }
 361
 362 static int acpi_pci_root_remove(struct acpi_device *device, int type)
 363 {
 364         struct acpi_pci_root *root = NULL;
 365
 366
 367         if (!device || !acpi_driver_data(device))
 368                 return -EINVAL;
 369
 370         root = acpi_driver_data(device);
 371
 372         kfree(root);
 373
 374         return 0;
 375 }
 376
 377 static int __init acpi_pci_root_init(void)
 378 {
 379
 380         if (acpi_pci_disabled)
 381                 return 0;
 382
 383         /* DEBUG:
 384            acpi_dbg_layer = ACPI_PCI_COMPONENT;
 385            acpi_dbg_level = 0xFFFFFFFF;
 386          */
 387
 388         if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
 389                 return -ENODEV;
 390
 391         return 0;
 392 }
 393
 394 subsys_initcall(acpi_pci_root_init);