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