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