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