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