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         acpi_handle handle;
  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->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                         continue;
 103                 *pptr = (*pptr)->next;
 104                 break;
 105         }
 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->handle);
 114         }
 115 }
 116
 117 EXPORT_SYMBOL(acpi_pci_unregister_driver);
 118
 119 static acpi_status
 120 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
 121 {
 122         int *busnr = (int *)data;
 123         struct acpi_resource_address64 address;
 124
 125         if (resource->id != ACPI_RSTYPE_ADDRESS16 &&
 126             resource->id != ACPI_RSTYPE_ADDRESS32 &&
 127             resource->id != ACPI_RSTYPE_ADDRESS64)
 128                 return AE_OK;
 129
 130         acpi_resource_to_address64(resource, &address);
 131         if ((address.address_length > 0) &&
 132             (address.resource_type == ACPI_BUS_NUMBER_RANGE))
 133                 *busnr = address.min_address_range;
 134
 135         return AE_OK;
 136 }
 137
 138 static acpi_status try_get_root_bridge_busnr(acpi_handle handle, int *busnum)
 139 {
 140         acpi_status status;
 141
 142         *busnum = -1;
 143         status =
 144             acpi_walk_resources(handle, METHOD_NAME__CRS,
 145                                 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 acpi_pci_root_add(struct acpi_device *device)
 155 {
 156         int result = 0;
 157         struct acpi_pci_root *root = NULL;
 158         struct acpi_pci_root *tmp;
 159         acpi_status status = AE_OK;
 160         unsigned long value = 0;
 161         acpi_handle handle = NULL;
 162
 163         ACPI_FUNCTION_TRACE("acpi_pci_root_add");
 164
 165         if (!device)
 166                 return_VALUE(-EINVAL);
 167
 168         root = kmalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 169         if (!root)
 170                 return_VALUE(-ENOMEM);
 171         memset(root, 0, sizeof(struct acpi_pci_root));
 172         INIT_LIST_HEAD(&root->node);
 173
 174         root->handle = device->handle;
 175         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 176         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 177         acpi_driver_data(device) = root;
 178
 179         /*
 180          * TBD: Doesn't the bus driver automatically set this?
 181          */
 182         device->ops.bind = acpi_pci_bind;
 183
 184         /*
 185          * Segment
 186          * -------
 187          * Obtained via _SEG, if exists, otherwise assumed to be zero (0).
 188          */
 189         status = acpi_evaluate_integer(root->handle, METHOD_NAME__SEG, NULL,
 190                                        &value);
 191         switch (status) {
 192         case AE_OK:
 193                 root->id.segment = (u16) value;
 194                 break;
 195         case AE_NOT_FOUND:
 196                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 197                                   "Assuming segment 0 (no _SEG)\n"));
 198                 root->id.segment = 0;
 199                 break;
 200         default:
 201                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _SEG\n"));
 202                 result = -ENODEV;
 203                 goto end;
 204         }
 205
 206         /*
 207          * Bus
 208          * ---
 209          * Obtained via _BBN, if exists, otherwise assumed to be zero (0).
 210          */
 211         status = acpi_evaluate_integer(root->handle, METHOD_NAME__BBN, NULL,
 212                                        &value);
 213         switch (status) {
 214         case AE_OK:
 215                 root->id.bus = (u16) value;
 216                 break;
 217         case AE_NOT_FOUND:
 218                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Assuming bus 0 (no _BBN)\n"));
 219                 root->id.bus = 0;
 220                 break;
 221         default:
 222                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _BBN\n"));
 223                 result = -ENODEV;
 224                 goto end;
 225         }
 226
 227         /* Some systems have wrong _BBN */
 228         list_for_each_entry(tmp, &acpi_pci_roots, node) {
 229                 if ((tmp->id.segment == root->id.segment)
 230                     && (tmp->id.bus == root->id.bus)) {
 231                         int bus = 0;
 232                         acpi_status status;
 233
 234                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 235                                           "Wrong _BBN value, please reboot and using option 'pci=noacpi'\n"));
 236
 237                         status = try_get_root_bridge_busnr(root->handle, &bus);
 238                         if (ACPI_FAILURE(status))
 239                                 break;
 240                         if (bus != root->id.bus) {
 241                                 printk(KERN_INFO PREFIX
 242                                        "PCI _CRS %d overrides _BBN 0\n", bus);
 243                                 root->id.bus = bus;
 244                         }
 245                         break;
 246                 }
 247         }
 248         /*
 249          * Device & Function
 250          * -----------------
 251          * Obtained from _ADR (which has already been evaluated for us).
 252          */
 253         root->id.device = device->pnp.bus_address >> 16;
 254         root->id.function = device->pnp.bus_address & 0xFFFF;
 255
 256         /*
 257          * TBD: Need PCI interface for enumeration/configuration of roots.
 258          */
 259
 260         /* TBD: Locking */
 261         list_add_tail(&root->node, &acpi_pci_roots);
 262
 263         printk(KERN_INFO PREFIX "%s [%s] (%04x:%02x)\n",
 264                acpi_device_name(device), acpi_device_bid(device),
 265                root->id.segment, root->id.bus);
 266
 267         /*
 268          * Scan the Root Bridge
 269          * --------------------
 270          * Must do this prior to any attempt to bind the root device, as the
 271          * PCI namespace does not get created until this call is made (and
 272          * thus the root bridge's pci_dev does not exist).
 273          */
 274         root->bus = pci_acpi_scan_root(device, root->id.segment, root->id.bus);
 275         if (!root->bus) {
 276                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 277                                   "Bus %04x:%02x not present in PCI namespace\n",
 278                                   root->id.segment, root->id.bus));
 279                 result = -ENODEV;
 280                 goto end;
 281         }
 282
 283         /*
 284          * Attach ACPI-PCI Context
 285          * -----------------------
 286          * Thus binding the ACPI and PCI devices.
 287          */
 288         result = acpi_pci_bind_root(device, &root->id, root->bus);
 289         if (result)
 290                 goto end;
 291
 292         /*
 293          * PCI Routing Table
 294          * -----------------
 295          * Evaluate and parse _PRT, if exists.
 296          */
 297         status = acpi_get_handle(root->handle, METHOD_NAME__PRT, &handle);
 298         if (ACPI_SUCCESS(status))
 299                 result = acpi_pci_irq_add_prt(root->handle, root->id.segment,
 300                                               root->id.bus);
 301
 302       end:
 303         if (result) {
 304                 if (!list_empty(&root->node))
 305                         list_del(&root->node);
 306                 kfree(root);
 307         }
 308
 309         return_VALUE(result);
 310 }
 311
 312 static int acpi_pci_root_start(struct acpi_device *device)
 313 {
 314         struct acpi_pci_root *root;
 315
 316         ACPI_FUNCTION_TRACE("acpi_pci_root_start");
 317
 318         list_for_each_entry(root, &acpi_pci_roots, node) {
 319                 if (root->handle == device->handle) {
 320                         pci_bus_add_devices(root->bus);
 321                         return_VALUE(0);
 322                 }
 323         }
 324         return_VALUE(-ENODEV);
 325 }
 326
 327 static int acpi_pci_root_remove(struct acpi_device *device, int type)
 328 {
 329         struct acpi_pci_root *root = NULL;
 330
 331         ACPI_FUNCTION_TRACE("acpi_pci_root_remove");
 332
 333         if (!device || !acpi_driver_data(device))
 334                 return_VALUE(-EINVAL);
 335
 336         root = (struct acpi_pci_root *)acpi_driver_data(device);
 337
 338         kfree(root);
 339
 340         return_VALUE(0);
 341 }
 342
 343 static int __init acpi_pci_root_init(void)
 344 {
 345         ACPI_FUNCTION_TRACE("acpi_pci_root_init");
 346
 347         if (acpi_pci_disabled)
 348                 return_VALUE(0);
 349
 350         /* DEBUG:
 351            acpi_dbg_layer = ACPI_PCI_COMPONENT;
 352            acpi_dbg_level = 0xFFFFFFFF;
 353          */
 354
 355         if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
 356                 return_VALUE(-ENODEV);
 357
 358         return_VALUE(0);
 359 }
 360
 361 subsys_initcall(acpi_pci_root_init);