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
  39 #define _COMPONENT              ACPI_PCI_COMPONENT
  40 ACPI_MODULE_NAME                ("pci_root")
  41
  42 #define ACPI_PCI_ROOT_CLASS             "pci_bridge"
  43 #define ACPI_PCI_ROOT_HID               "PNP0A03"
  44 #define ACPI_PCI_ROOT_DRIVER_NAME       "ACPI PCI Root Bridge Driver"
  45 #define ACPI_PCI_ROOT_DEVICE_NAME       "PCI Root Bridge"
  46
  47 static int acpi_pci_root_add (struct acpi_device *device);
  48 static int acpi_pci_root_remove (struct acpi_device *device, int type);
  49 static int acpi_pci_root_start (struct acpi_device *device);
  50
  51 static struct acpi_driver acpi_pci_root_driver = {
  52         .name =         ACPI_PCI_ROOT_DRIVER_NAME,
  53         .class =        ACPI_PCI_ROOT_CLASS,
  54         .ids =          ACPI_PCI_ROOT_HID,
  55         .ops =          {
  56                                 .add =    acpi_pci_root_add,
  57                                 .remove = acpi_pci_root_remove,
  58                                 .start =  acpi_pci_root_start,
  59                         },
  60 };
  61
  62 struct acpi_pci_root {
  63         struct list_head        node;
  64         acpi_handle             handle;
  65         struct acpi_pci_id      id;
  66         struct pci_bus          *bus;
  67 };
  68
  69 static LIST_HEAD(acpi_pci_roots);
  70
  71 static struct acpi_pci_driver *sub_driver;
  72
  73 int acpi_pci_register_driver(struct acpi_pci_driver *driver)
  74 {
  75         int n = 0;
  76         struct list_head *entry;
  77
  78         struct acpi_pci_driver **pptr = &sub_driver;
  79         while (*pptr)
  80                 pptr = &(*pptr)->next;
  81         *pptr = driver;
  82
  83         if (!driver->add)
  84                 return 0;
  85
  86         list_for_each(entry, &acpi_pci_roots) {
  87                 struct acpi_pci_root *root;
  88                 root = list_entry(entry, struct acpi_pci_root, node);
  89                 driver->add(root->handle);
  90                 n++;
  91         }
  92
  93         return n;
  94 }
  95 EXPORT_SYMBOL(acpi_pci_register_driver);
  96
  97 void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
  98 {
  99         struct list_head *entry;
 100
 101         struct acpi_pci_driver **pptr = &sub_driver;
 102         while (*pptr) {
 103                 if (*pptr != driver)
 104                         continue;
 105                 *pptr = (*pptr)->next;
 106                 break;
 107         }
 108
 109         if (!driver->remove)
 110                 return;
 111
 112         list_for_each(entry, &acpi_pci_roots) {
 113                 struct acpi_pci_root *root;
 114                 root = list_entry(entry, struct acpi_pci_root, node);
 115                 driver->remove(root->handle);
 116         }
 117 }
 118 EXPORT_SYMBOL(acpi_pci_unregister_driver);
 119
 120 static acpi_status
 121 get_root_bridge_busnr_callback (struct acpi_resource *resource, void *data)
 122 {
 123         int *busnr = (int *)data;
 124         struct acpi_resource_address64 address;
 125
 126         if (resource->id != ACPI_RSTYPE_ADDRESS16 &&
 127             resource->id != ACPI_RSTYPE_ADDRESS32 &&
 128             resource->id != ACPI_RSTYPE_ADDRESS64)
 129                 return AE_OK;
 130
 131         acpi_resource_to_address64(resource, &address);
 132         if ((address.address_length > 0) &&
 133            (address.resource_type == ACPI_BUS_NUMBER_RANGE))
 134                 *busnr = address.min_address_range;
 135
 136         return AE_OK;
 137 }
 138
 139 static acpi_status
 140 try_get_root_bridge_busnr(acpi_handle handle, int *busnum)
 141 {
 142         acpi_status status;
 143
 144         *busnum = -1;
 145         status = acpi_walk_resources(handle, METHOD_NAME__CRS, get_root_bridge_busnr_callback, busnum);
 146         if (ACPI_FAILURE(status))
 147                 return status;
 148         /* Check if we really get a bus number from _CRS */
 149         if (*busnum == -1)
 150                 return AE_ERROR;
 151         return AE_OK;
 152 }
 153
 154 static int
 155 acpi_pci_root_add (
 156         struct acpi_device      *device)
 157 {
 158         int                     result = 0;
 159         struct acpi_pci_root    *root = NULL;
 160         struct acpi_pci_root    *tmp;
 161         acpi_status             status = AE_OK;
 162         unsigned long           value = 0;
 163         acpi_handle             handle = NULL;
 164
 165         ACPI_FUNCTION_TRACE("acpi_pci_root_add");
 166
 167         if (!device)
 168                 return_VALUE(-EINVAL);
 169
 170         root = kmalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 171         if (!root)
 172                 return_VALUE(-ENOMEM);
 173         memset(root, 0, sizeof(struct acpi_pci_root));
 174         INIT_LIST_HEAD(&root->node);
 175
 176         root->handle = device->handle;
 177         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 178         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 179         acpi_driver_data(device) = root;
 180
 181         /*
 182          * TBD: Doesn't the bus driver automatically set this?
 183          */
 184         device->ops.bind = acpi_pci_bind;
 185
 186         /*
 187          * Segment
 188          * -------
 189          * Obtained via _SEG, if exists, otherwise assumed to be zero (0).
 190          */
 191         status = acpi_evaluate_integer(root->handle, METHOD_NAME__SEG, NULL,
 192                 &value);
 193         switch (status) {
 194         case AE_OK:
 195                 root->id.segment = (u16) value;
 196                 break;
 197         case AE_NOT_FOUND:
 198                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 199                         "Assuming segment 0 (no _SEG)\n"));
 200                 root->id.segment = 0;
 201                 break;
 202         default:
 203                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _SEG\n"));
 204                 result = -ENODEV;
 205                 goto end;
 206         }
 207
 208         /*
 209          * Bus
 210          * ---
 211          * Obtained via _BBN, if exists, otherwise assumed to be zero (0).
 212          */
 213         status = acpi_evaluate_integer(root->handle, METHOD_NAME__BBN, NULL,
 214                 &value);
 215         switch (status) {
 216         case AE_OK:
 217                 root->id.bus = (u16) value;
 218                 break;
 219         case AE_NOT_FOUND:
 220                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Assuming bus 0 (no _BBN)\n"));
 221                 root->id.bus = 0;
 222                 break;
 223         default:
 224                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _BBN\n"));
 225                 result = -ENODEV;
 226                 goto end;
 227         }
 228
 229         /* Some systems have wrong _BBN */
 230         list_for_each_entry(tmp, &acpi_pci_roots, node) {
 231                 if ((tmp->id.segment == root->id.segment)
 232                                 && (tmp->id.bus == root->id.bus)) {
 233                         int bus = 0;
 234                         acpi_status status;
 235
 236                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 237                                 "Wrong _BBN value, please reboot and using option 'pci=noacpi'\n"));
 238
 239                         status = try_get_root_bridge_busnr(root->handle, &bus);
 240                         if (ACPI_FAILURE(status))
 241                                 break;
 242                         if (bus != root->id.bus) {
 243                                 printk(KERN_INFO PREFIX "PCI _CRS %d overrides _BBN 0\n", bus);
 244                                 root->id.bus = bus;
 245                         }
 246                         break;
 247                 }
 248         }
 249         /*
 250          * Device & Function
 251          * -----------------
 252          * Obtained from _ADR (which has already been evaluated for us).
 253          */
 254         root->id.device = device->pnp.bus_address >> 16;
 255         root->id.function = device->pnp.bus_address & 0xFFFF;
 256
 257         /*
 258          * TBD: Need PCI interface for enumeration/configuration of roots.
 259          */
 260
 261         /* TBD: Locking */
 262         list_add_tail(&root->node, &acpi_pci_roots);
 263
 264         printk(KERN_INFO PREFIX "%s [%s] (%04x:%02x)\n",
 265                 acpi_device_name(device), acpi_device_bid(device),
 266                 root->id.segment, root->id.bus);
 267
 268         /*
 269          * Scan the Root Bridge
 270          * --------------------
 271          * Must do this prior to any attempt to bind the root device, as the
 272          * PCI namespace does not get created until this call is made (and
 273          * thus the root bridge's pci_dev does not exist).
 274          */
 275         root->bus = pci_acpi_scan_root(device, root->id.segment, root->id.bus);
 276         if (!root->bus) {
 277                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 278                         "Bus %04x:%02x not present in PCI namespace\n",
 279                         root->id.segment, root->id.bus));
 280                 result = -ENODEV;
 281                 goto end;
 282         }
 283
 284         /*
 285          * Attach ACPI-PCI Context
 286          * -----------------------
 287          * Thus binding the ACPI and PCI devices.
 288          */
 289         result = acpi_pci_bind_root(device, &root->id, root->bus);
 290         if (result)
 291                 goto end;
 292
 293         /*
 294          * PCI Routing Table
 295          * -----------------
 296          * Evaluate and parse _PRT, if exists.
 297          */
 298         status = acpi_get_handle(root->handle, METHOD_NAME__PRT, &handle);
 299         if (ACPI_SUCCESS(status))
 300                 result = acpi_pci_irq_add_prt(root->handle, root->id.segment,
 301                         root->id.bus);
 302
 303 end:
 304         if (result) {
 305                 if (!list_empty(&root->node))
 306                         list_del(&root->node);
 307                 kfree(root);
 308         }
 309
 310         return_VALUE(result);
 311 }
 312
 313 static int
 314 acpi_pci_root_start (
 315         struct acpi_device      *device)
 316 {
 317         struct acpi_pci_root    *root;
 318
 319         ACPI_FUNCTION_TRACE("acpi_pci_root_start");
 320
 321         list_for_each_entry(root, &acpi_pci_roots, node) {
 322                 if (root->handle == device->handle) {
 323                         pci_bus_add_devices(root->bus);
 324                         return_VALUE(0);
 325                 }
 326         }
 327         return_VALUE(-ENODEV);
 328 }
 329
 330 static int
 331 acpi_pci_root_remove (
 332         struct acpi_device      *device,
 333         int                     type)
 334 {
 335         struct acpi_pci_root    *root = NULL;
 336
 337         ACPI_FUNCTION_TRACE("acpi_pci_root_remove");
 338
 339         if (!device || !acpi_driver_data(device))
 340                 return_VALUE(-EINVAL);
 341
 342         root = (struct acpi_pci_root *) acpi_driver_data(device);
 343
 344         kfree(root);
 345
 346         return_VALUE(0);
 347 }
 348
 349
 350 static int __init acpi_pci_root_init (void)
 351 {
 352         ACPI_FUNCTION_TRACE("acpi_pci_root_init");
 353
 354         if (acpi_pci_disabled)
 355                 return_VALUE(0);
 356
 357         /* DEBUG:
 358         acpi_dbg_layer = ACPI_PCI_COMPONENT;
 359         acpi_dbg_level = 0xFFFFFFFF;
 360          */
 361
 362         if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
 363                 return_VALUE(-ENODEV);
 364
 365         return_VALUE(0);
 366 }
 367
 368 subsys_initcall(acpi_pci_root_init);
 369