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/pci-acpi.h>
  35 #include <linux/acpi.h>
  36 #include <acpi/acpi_bus.h>
  37 #include <acpi/acpi_drivers.h>
  38
  39 #define _COMPONENT              ACPI_PCI_COMPONENT
  40 ACPI_MODULE_NAME("pci_root");
  41 #define ACPI_PCI_ROOT_CLASS             "pci_bridge"
  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_device_id root_device_ids[] = {
  48         {"PNP0A03", 0},
  49         {"", 0},
  50 };
  51 MODULE_DEVICE_TABLE(acpi, root_device_ids);
  52
  53 static struct acpi_driver acpi_pci_root_driver = {
  54         .name = "pci_root",
  55         .class = ACPI_PCI_ROOT_CLASS,
  56         .ids = root_device_ids,
  57         .ops = {
  58                 .add = acpi_pci_root_add,
  59                 .remove = acpi_pci_root_remove,
  60                 .start = acpi_pci_root_start,
  61                 },
  62 };
  63
  64 struct acpi_pci_root {
  65         struct list_head node;
  66         struct acpi_device * device;
  67         struct acpi_pci_id id;
  68         struct pci_bus *bus;
  69 };
  70
  71 static LIST_HEAD(acpi_pci_roots);
  72
  73 static struct acpi_pci_driver *sub_driver;
  74
  75 int acpi_pci_register_driver(struct acpi_pci_driver *driver)
  76 {
  77         int n = 0;
  78         struct list_head *entry;
  79
  80         struct acpi_pci_driver **pptr = &sub_driver;
  81         while (*pptr)
  82                 pptr = &(*pptr)->next;
  83         *pptr = driver;
  84
  85         if (!driver->add)
  86                 return 0;
  87
  88         list_for_each(entry, &acpi_pci_roots) {
  89                 struct acpi_pci_root *root;
  90                 root = list_entry(entry, struct acpi_pci_root, node);
  91                 driver->add(root->device->handle);
  92                 n++;
  93         }
  94
  95         return n;
  96 }
  97
  98 EXPORT_SYMBOL(acpi_pci_register_driver);
  99
 100 void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
 101 {
 102         struct list_head *entry;
 103
 104         struct acpi_pci_driver **pptr = &sub_driver;
 105         while (*pptr) {
 106                 if (*pptr == driver)
 107                         break;
 108                 pptr = &(*pptr)->next;
 109         }
 110         BUG_ON(!*pptr);
 111         *pptr = (*pptr)->next;
 112
 113         if (!driver->remove)
 114                 return;
 115
 116         list_for_each(entry, &acpi_pci_roots) {
 117                 struct acpi_pci_root *root;
 118                 root = list_entry(entry, struct acpi_pci_root, node);
 119                 driver->remove(root->device->handle);
 120         }
 121 }
 122
 123 EXPORT_SYMBOL(acpi_pci_unregister_driver);
 124
 125 acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
 126 {
 127         struct acpi_pci_root *tmp;
 128
 129         list_for_each_entry(tmp, &acpi_pci_roots, node) {
 130                 if ((tmp->id.segment == (u16) seg) && (tmp->id.bus == (u16) bus))
 131                         return tmp->device->handle;
 132         }
 133         return NULL;
 134 }
 135
 136 EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
 137
 138 static acpi_status
 139 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
 140 {
 141         int *busnr = data;
 142         struct acpi_resource_address64 address;
 143
 144         if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
 145             resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
 146             resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
 147                 return AE_OK;
 148
 149         acpi_resource_to_address64(resource, &address);
 150         if ((address.address_length > 0) &&
 151             (address.resource_type == ACPI_BUS_NUMBER_RANGE))
 152                 *busnr = address.minimum;
 153
 154         return AE_OK;
 155 }
 156
 157 static acpi_status try_get_root_bridge_busnr(acpi_handle handle, int *busnum)
 158 {
 159         acpi_status status;
 160
 161         *busnum = -1;
 162         status =
 163             acpi_walk_resources(handle, METHOD_NAME__CRS,
 164                                 get_root_bridge_busnr_callback, busnum);
 165         if (ACPI_FAILURE(status))
 166                 return status;
 167         /* Check if we really get a bus number from _CRS */
 168         if (*busnum == -1)
 169                 return AE_ERROR;
 170         return AE_OK;
 171 }
 172
 173 static void acpi_pci_bridge_scan(struct acpi_device *device)
 174 {
 175         int status;
 176         struct acpi_device *child = NULL;
 177
 178         if (device->flags.bus_address)
 179                 if (device->parent && device->parent->ops.bind) {
 180                         status = device->parent->ops.bind(device);
 181                         if (!status) {
 182                                 list_for_each_entry(child, &device->children, node)
 183                                         acpi_pci_bridge_scan(child);
 184                         }
 185                 }
 186 }
 187
 188 static int __devinit acpi_pci_root_add(struct acpi_device *device)
 189 {
 190         int result = 0;
 191         struct acpi_pci_root *root = NULL;
 192         struct acpi_pci_root *tmp;
 193         acpi_status status = AE_OK;
 194         unsigned long long value = 0;
 195         acpi_handle handle = NULL;
 196         struct acpi_device *child;
 197         u32 flags, base_flags;
 198
 199
 200         if (!device)
 201                 return -EINVAL;
 202
 203         root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 204         if (!root)
 205                 return -ENOMEM;
 206         INIT_LIST_HEAD(&root->node);
 207
 208         root->device = device;
 209         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 210         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 211         device->driver_data = root;
 212
 213         device->ops.bind = acpi_pci_bind;
 214
 215         /*
 216          * All supported architectures that use ACPI have support for
 217          * PCI domains, so we indicate this in _OSC support capabilities.
 218          */
 219         flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
 220         pci_acpi_osc_support(device->handle, flags);
 221
 222         /*
 223          * Segment
 224          * -------
 225          * Obtained via _SEG, if exists, otherwise assumed to be zero (0).
 226          */
 227         status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
 228                                        &value);
 229         switch (status) {
 230         case AE_OK:
 231                 root->id.segment = (u16) value;
 232                 break;
 233         case AE_NOT_FOUND:
 234                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 235                                   "Assuming segment 0 (no _SEG)\n"));
 236                 root->id.segment = 0;
 237                 break;
 238         default:
 239                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SEG"));
 240                 result = -ENODEV;
 241                 goto end;
 242         }
 243
 244         /*
 245          * Bus
 246          * ---
 247          * Obtained via _BBN, if exists, otherwise assumed to be zero (0).
 248          */
 249         status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN, NULL,
 250                                        &value);
 251         switch (status) {
 252         case AE_OK:
 253                 root->id.bus = (u16) value;
 254                 break;
 255         case AE_NOT_FOUND:
 256                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Assuming bus 0 (no _BBN)\n"));
 257                 root->id.bus = 0;
 258                 break;
 259         default:
 260                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BBN"));
 261                 result = -ENODEV;
 262                 goto end;
 263         }
 264
 265         /* Some systems have wrong _BBN */
 266         list_for_each_entry(tmp, &acpi_pci_roots, node) {
 267                 if ((tmp->id.segment == root->id.segment)
 268                     && (tmp->id.bus == root->id.bus)) {
 269                         int bus = 0;
 270                         acpi_status status;
 271
 272                         printk(KERN_ERR PREFIX
 273                                     "Wrong _BBN value, reboot"
 274                                     " and use option 'pci=noacpi'\n");
 275
 276                         status = try_get_root_bridge_busnr(device->handle, &bus);
 277                         if (ACPI_FAILURE(status))
 278                                 break;
 279                         if (bus != root->id.bus) {
 280                                 printk(KERN_INFO PREFIX
 281                                        "PCI _CRS %d overrides _BBN 0\n", bus);
 282                                 root->id.bus = bus;
 283                         }
 284                         break;
 285                 }
 286         }
 287         /*
 288          * Device & Function
 289          * -----------------
 290          * Obtained from _ADR (which has already been evaluated for us).
 291          */
 292         root->id.device = device->pnp.bus_address >> 16;
 293         root->id.function = device->pnp.bus_address & 0xFFFF;
 294
 295         /*
 296          * TBD: Need PCI interface for enumeration/configuration of roots.
 297          */
 298
 299         /* TBD: Locking */
 300         list_add_tail(&root->node, &acpi_pci_roots);
 301
 302         printk(KERN_INFO PREFIX "%s [%s] (%04x:%02x)\n",
 303                acpi_device_name(device), acpi_device_bid(device),
 304                root->id.segment, root->id.bus);
 305
 306         /*
 307          * Scan the Root Bridge
 308          * --------------------
 309          * Must do this prior to any attempt to bind the root device, as the
 310          * PCI namespace does not get created until this call is made (and
 311          * thus the root bridge's pci_dev does not exist).
 312          */
 313         root->bus = pci_acpi_scan_root(device, root->id.segment, root->id.bus);
 314         if (!root->bus) {
 315                 printk(KERN_ERR PREFIX
 316                             "Bus %04x:%02x not present in PCI namespace\n",
 317                             root->id.segment, root->id.bus);
 318                 result = -ENODEV;
 319                 goto end;
 320         }
 321
 322         /*
 323          * Attach ACPI-PCI Context
 324          * -----------------------
 325          * Thus binding the ACPI and PCI devices.
 326          */
 327         result = acpi_pci_bind_root(device, &root->id, root->bus);
 328         if (result)
 329                 goto end;
 330
 331         /*
 332          * PCI Routing Table
 333          * -----------------
 334          * Evaluate and parse _PRT, if exists.
 335          */
 336         status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
 337         if (ACPI_SUCCESS(status))
 338                 result = acpi_pci_irq_add_prt(device->handle, root->id.segment,
 339                                               root->id.bus);
 340
 341         /*
 342          * Scan and bind all _ADR-Based Devices
 343          */
 344         list_for_each_entry(child, &device->children, node)
 345                 acpi_pci_bridge_scan(child);
 346
 347         /* Indicate support for various _OSC capabilities. */
 348         if (pci_ext_cfg_avail(root->bus->self))
 349                 flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
 350         if (pcie_aspm_enabled())
 351                 flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
 352                         OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
 353         if (flags != base_flags)
 354                 pci_acpi_osc_support(device->handle, flags);
 355
 356       end:
 357         if (result) {
 358                 if (!list_empty(&root->node))
 359                         list_del(&root->node);
 360                 kfree(root);
 361         }
 362
 363         return result;
 364 }
 365
 366 static int acpi_pci_root_start(struct acpi_device *device)
 367 {
 368         struct acpi_pci_root *root;
 369
 370
 371         list_for_each_entry(root, &acpi_pci_roots, node) {
 372                 if (root->device == device) {
 373                         pci_bus_add_devices(root->bus);
 374                         return 0;
 375                 }
 376         }
 377         return -ENODEV;
 378 }
 379
 380 static int acpi_pci_root_remove(struct acpi_device *device, int type)
 381 {
 382         struct acpi_pci_root *root = NULL;
 383
 384
 385         if (!device || !acpi_driver_data(device))
 386                 return -EINVAL;
 387
 388         root = acpi_driver_data(device);
 389
 390         kfree(root);
 391
 392         return 0;
 393 }
 394
 395 static int __init acpi_pci_root_init(void)
 396 {
 397         if (acpi_pci_disabled)
 398                 return 0;
 399
 400         if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
 401                 return -ENODEV;
 402
 403         return 0;
 404 }
 405
 406 subsys_initcall(acpi_pci_root_init);