drivers/acpi/acpica/evhandler.c

   1 /******************************************************************************
   2  *
   3  * Module Name: evhandler - Support for Address Space handlers
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2016, Intel Corp.
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44 #include <acpi/acpi.h>
  45 #include "accommon.h"
  46 #include "acevents.h"
  47 #include "acnamesp.h"
  48 #include "acinterp.h"
  49
  50 #define _COMPONENT          ACPI_EVENTS
  51 ACPI_MODULE_NAME("evhandler")
  52
  53 /* Local prototypes */
  54 static acpi_status
  55 acpi_ev_install_handler(acpi_handle obj_handle,
  56                         u32 level, void *context, void **return_value);
  57
  58 /* These are the address spaces that will get default handlers */
  59
  60 u8 acpi_gbl_default_address_spaces[ACPI_NUM_DEFAULT_SPACES] = {
  61         ACPI_ADR_SPACE_SYSTEM_MEMORY,
  62         ACPI_ADR_SPACE_SYSTEM_IO,
  63         ACPI_ADR_SPACE_PCI_CONFIG,
  64         ACPI_ADR_SPACE_DATA_TABLE
  65 };
  66
  67 /*******************************************************************************
  68  *
  69  * FUNCTION:    acpi_ev_install_region_handlers
  70  *
  71  * PARAMETERS:  None
  72  *
  73  * RETURN:      Status
  74  *
  75  * DESCRIPTION: Installs the core subsystem default address space handlers.
  76  *
  77  ******************************************************************************/
  78
  79 acpi_status acpi_ev_install_region_handlers(void)
  80 {
  81         acpi_status status;
  82         u32 i;
  83
  84         ACPI_FUNCTION_TRACE(ev_install_region_handlers);
  85
  86         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
  87         if (ACPI_FAILURE(status)) {
  88                 return_ACPI_STATUS(status);
  89         }
  90
  91         /*
  92          * All address spaces (PCI Config, EC, SMBus) are scope dependent and
  93          * registration must occur for a specific device.
  94          *
  95          * In the case of the system memory and IO address spaces there is
  96          * currently no device associated with the address space. For these we
  97          * use the root.
  98          *
  99          * We install the default PCI config space handler at the root so that
 100          * this space is immediately available even though the we have not
 101          * enumerated all the PCI Root Buses yet. This is to conform to the ACPI
 102          * specification which states that the PCI config space must be always
 103          * available -- even though we are nowhere near ready to find the PCI root
 104          * buses at this point.
 105          *
 106          * NOTE: We ignore AE_ALREADY_EXISTS because this means that a handler
 107          * has already been installed (via acpi_install_address_space_handler).
 108          * Similar for AE_SAME_HANDLER.
 109          */
 110         for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++) {
 111                 status = acpi_ev_install_space_handler(acpi_gbl_root_node,
 112                                                        acpi_gbl_default_address_spaces
 113                                                        [i],
 114                                                        ACPI_DEFAULT_HANDLER,
 115                                                        NULL, NULL);
 116                 switch (status) {
 117                 case AE_OK:
 118                 case AE_SAME_HANDLER:
 119                 case AE_ALREADY_EXISTS:
 120
 121                         /* These exceptions are all OK */
 122
 123                         status = AE_OK;
 124                         break;
 125
 126                 default:
 127
 128                         goto unlock_and_exit;
 129                 }
 130         }
 131
 132 unlock_and_exit:
 133         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 134         return_ACPI_STATUS(status);
 135 }
 136
 137 /*******************************************************************************
 138  *
 139  * FUNCTION:    acpi_ev_has_default_handler
 140  *
 141  * PARAMETERS:  node                - Namespace node for the device
 142  *              space_id            - The address space ID
 143  *
 144  * RETURN:      TRUE if default handler is installed, FALSE otherwise
 145  *
 146  * DESCRIPTION: Check if the default handler is installed for the requested
 147  *              space ID.
 148  *
 149  ******************************************************************************/
 150
 151 u8
 152 acpi_ev_has_default_handler(struct acpi_namespace_node *node,
 153                             acpi_adr_space_type space_id)
 154 {
 155         union acpi_operand_object *obj_desc;
 156         union acpi_operand_object *handler_obj;
 157
 158         /* Must have an existing internal object */
 159
 160         obj_desc = acpi_ns_get_attached_object(node);
 161         if (obj_desc) {
 162                 handler_obj = obj_desc->common_notify.handler;
 163
 164                 /* Walk the linked list of handlers for this object */
 165
 166                 while (handler_obj) {
 167                         if (handler_obj->address_space.space_id == space_id) {
 168                                 if (handler_obj->address_space.handler_flags &
 169                                     ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
 170                                         return (TRUE);
 171                                 }
 172                         }
 173
 174                         handler_obj = handler_obj->address_space.next;
 175                 }
 176         }
 177
 178         return (FALSE);
 179 }
 180
 181 /*******************************************************************************
 182  *
 183  * FUNCTION:    acpi_ev_install_handler
 184  *
 185  * PARAMETERS:  walk_namespace callback
 186  *
 187  * DESCRIPTION: This routine installs an address handler into objects that are
 188  *              of type Region or Device.
 189  *
 190  *              If the Object is a Device, and the device has a handler of
 191  *              the same type then the search is terminated in that branch.
 192  *
 193  *              This is because the existing handler is closer in proximity
 194  *              to any more regions than the one we are trying to install.
 195  *
 196  ******************************************************************************/
 197
 198 static acpi_status
 199 acpi_ev_install_handler(acpi_handle obj_handle,
 200                         u32 level, void *context, void **return_value)
 201 {
 202         union acpi_operand_object *handler_obj;
 203         union acpi_operand_object *next_handler_obj;
 204         union acpi_operand_object *obj_desc;
 205         struct acpi_namespace_node *node;
 206         acpi_status status;
 207
 208         ACPI_FUNCTION_NAME(ev_install_handler);
 209
 210         handler_obj = (union acpi_operand_object *)context;
 211
 212         /* Parameter validation */
 213
 214         if (!handler_obj) {
 215                 return (AE_OK);
 216         }
 217
 218         /* Convert and validate the device handle */
 219
 220         node = acpi_ns_validate_handle(obj_handle);
 221         if (!node) {
 222                 return (AE_BAD_PARAMETER);
 223         }
 224
 225         /*
 226          * We only care about regions and objects that are allowed to have
 227          * address space handlers
 228          */
 229         if ((node->type != ACPI_TYPE_DEVICE) &&
 230             (node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
 231                 return (AE_OK);
 232         }
 233
 234         /* Check for an existing internal object */
 235
 236         obj_desc = acpi_ns_get_attached_object(node);
 237         if (!obj_desc) {
 238
 239                 /* No object, just exit */
 240
 241                 return (AE_OK);
 242         }
 243
 244         /* Devices are handled different than regions */
 245
 246         if (obj_desc->common.type == ACPI_TYPE_DEVICE) {
 247
 248                 /* Check if this Device already has a handler for this address space */
 249
 250                 next_handler_obj =
 251                     acpi_ev_find_region_handler(handler_obj->address_space.
 252                                                 space_id,
 253                                                 obj_desc->common_notify.
 254                                                 handler);
 255                 if (next_handler_obj) {
 256
 257                         /* Found a handler, is it for the same address space? */
 258
 259                         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 260                                           "Found handler for region [%s] in device %p(%p) handler %p\n",
 261                                           acpi_ut_get_region_name(handler_obj->
 262                                                                   address_space.
 263                                                                   space_id),
 264                                           obj_desc, next_handler_obj,
 265                                           handler_obj));
 266
 267                         /*
 268                          * Since the object we found it on was a device, then it means
 269                          * that someone has already installed a handler for the branch
 270                          * of the namespace from this device on. Just bail out telling
 271                          * the walk routine to not traverse this branch. This preserves
 272                          * the scoping rule for handlers.
 273                          */
 274                         return (AE_CTRL_DEPTH);
 275                 }
 276
 277                 /*
 278                  * As long as the device didn't have a handler for this space we
 279                  * don't care about it. We just ignore it and proceed.
 280                  */
 281                 return (AE_OK);
 282         }
 283
 284         /* Object is a Region */
 285
 286         if (obj_desc->region.space_id != handler_obj->address_space.space_id) {
 287
 288                 /* This region is for a different address space, just ignore it */
 289
 290                 return (AE_OK);
 291         }
 292
 293         /*
 294          * Now we have a region and it is for the handler's address space type.
 295          *
 296          * First disconnect region for any previous handler (if any)
 297          */
 298         acpi_ev_detach_region(obj_desc, FALSE);
 299
 300         /* Connect the region to the new handler */
 301
 302         status = acpi_ev_attach_region(handler_obj, obj_desc, FALSE);
 303         return (status);
 304 }
 305
 306 /*******************************************************************************
 307  *
 308  * FUNCTION:    acpi_ev_find_region_handler
 309  *
 310  * PARAMETERS:  space_id        - The address space ID
 311  *              handler_obj     - Head of the handler object list
 312  *
 313  * RETURN:      Matching handler object. NULL if space ID not matched
 314  *
 315  * DESCRIPTION: Search a handler object list for a match on the address
 316  *              space ID.
 317  *
 318  ******************************************************************************/
 319
 320 union acpi_operand_object *acpi_ev_find_region_handler(acpi_adr_space_type
 321                                                        space_id,
 322                                                        union acpi_operand_object
 323                                                        *handler_obj)
 324 {
 325
 326         /* Walk the handler list for this device */
 327
 328         while (handler_obj) {
 329
 330                 /* Same space_id indicates a handler is installed */
 331
 332                 if (handler_obj->address_space.space_id == space_id) {
 333                         return (handler_obj);
 334                 }
 335
 336                 /* Next handler object */
 337
 338                 handler_obj = handler_obj->address_space.next;
 339         }
 340
 341         return (NULL);
 342 }
 343
 344 /*******************************************************************************
 345  *
 346  * FUNCTION:    acpi_ev_install_space_handler
 347  *
 348  * PARAMETERS:  node            - Namespace node for the device
 349  *              space_id        - The address space ID
 350  *              handler         - Address of the handler
 351  *              setup           - Address of the setup function
 352  *              context         - Value passed to the handler on each access
 353  *
 354  * RETURN:      Status
 355  *
 356  * DESCRIPTION: Install a handler for all op_regions of a given space_id.
 357  *              Assumes namespace is locked
 358  *
 359  ******************************************************************************/
 360
 361 acpi_status
 362 acpi_ev_install_space_handler(struct acpi_namespace_node *node,
 363                               acpi_adr_space_type space_id,
 364                               acpi_adr_space_handler handler,
 365                               acpi_adr_space_setup setup, void *context)
 366 {
 367         union acpi_operand_object *obj_desc;
 368         union acpi_operand_object *handler_obj;
 369         acpi_status status = AE_OK;
 370         acpi_object_type type;
 371         u8 flags = 0;
 372
 373         ACPI_FUNCTION_TRACE(ev_install_space_handler);
 374
 375         /*
 376          * This registration is valid for only the types below and the root.
 377          * The root node is where the default handlers get installed.
 378          */
 379         if ((node->type != ACPI_TYPE_DEVICE) &&
 380             (node->type != ACPI_TYPE_PROCESSOR) &&
 381             (node->type != ACPI_TYPE_THERMAL) && (node != acpi_gbl_root_node)) {
 382                 status = AE_BAD_PARAMETER;
 383                 goto unlock_and_exit;
 384         }
 385
 386         if (handler == ACPI_DEFAULT_HANDLER) {
 387                 flags = ACPI_ADDR_HANDLER_DEFAULT_INSTALLED;
 388
 389                 switch (space_id) {
 390                 case ACPI_ADR_SPACE_SYSTEM_MEMORY:
 391
 392                         handler = acpi_ex_system_memory_space_handler;
 393                         setup = acpi_ev_system_memory_region_setup;
 394                         break;
 395
 396                 case ACPI_ADR_SPACE_SYSTEM_IO:
 397
 398                         handler = acpi_ex_system_io_space_handler;
 399                         setup = acpi_ev_io_space_region_setup;
 400                         break;
 401
 402                 case ACPI_ADR_SPACE_PCI_CONFIG:
 403
 404                         handler = acpi_ex_pci_config_space_handler;
 405                         setup = acpi_ev_pci_config_region_setup;
 406                         break;
 407
 408                 case ACPI_ADR_SPACE_CMOS:
 409
 410                         handler = acpi_ex_cmos_space_handler;
 411                         setup = acpi_ev_cmos_region_setup;
 412                         break;
 413
 414                 case ACPI_ADR_SPACE_PCI_BAR_TARGET:
 415
 416                         handler = acpi_ex_pci_bar_space_handler;
 417                         setup = acpi_ev_pci_bar_region_setup;
 418                         break;
 419
 420                 case ACPI_ADR_SPACE_DATA_TABLE:
 421
 422                         handler = acpi_ex_data_table_space_handler;
 423                         setup = NULL;
 424                         break;
 425
 426                 default:
 427
 428                         status = AE_BAD_PARAMETER;
 429                         goto unlock_and_exit;
 430                 }
 431         }
 432
 433         /* If the caller hasn't specified a setup routine, use the default */
 434
 435         if (!setup) {
 436                 setup = acpi_ev_default_region_setup;
 437         }
 438
 439         /* Check for an existing internal object */
 440
 441         obj_desc = acpi_ns_get_attached_object(node);
 442         if (obj_desc) {
 443                 /*
 444                  * The attached device object already exists. Now make sure
 445                  * the handler is not already installed.
 446                  */
 447                 handler_obj = acpi_ev_find_region_handler(space_id,
 448                                                           obj_desc->
 449                                                           common_notify.
 450                                                           handler);
 451
 452                 if (handler_obj) {
 453                         if (handler_obj->address_space.handler == handler) {
 454                                 /*
 455                                  * It is (relatively) OK to attempt to install the SAME
 456                                  * handler twice. This can easily happen with the
 457                                  * PCI_Config space.
 458                                  */
 459                                 status = AE_SAME_HANDLER;
 460                                 goto unlock_and_exit;
 461                         } else {
 462                                 /* A handler is already installed */
 463
 464                                 status = AE_ALREADY_EXISTS;
 465                         }
 466
 467                         goto unlock_and_exit;
 468                 }
 469         } else {
 470                 ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 471                                   "Creating object on Device %p while installing handler\n",
 472                                   node));
 473
 474                 /* obj_desc does not exist, create one */
 475
 476                 if (node->type == ACPI_TYPE_ANY) {
 477                         type = ACPI_TYPE_DEVICE;
 478                 } else {
 479                         type = node->type;
 480                 }
 481
 482                 obj_desc = acpi_ut_create_internal_object(type);
 483                 if (!obj_desc) {
 484                         status = AE_NO_MEMORY;
 485                         goto unlock_and_exit;
 486                 }
 487
 488                 /* Init new descriptor */
 489
 490                 obj_desc->common.type = (u8)type;
 491
 492                 /* Attach the new object to the Node */
 493
 494                 status = acpi_ns_attach_object(node, obj_desc, type);
 495
 496                 /* Remove local reference to the object */
 497
 498                 acpi_ut_remove_reference(obj_desc);
 499
 500                 if (ACPI_FAILURE(status)) {
 501                         goto unlock_and_exit;
 502                 }
 503         }
 504
 505         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 506                           "Installing address handler for region %s(%X) "
 507                           "on Device %4.4s %p(%p)\n",
 508                           acpi_ut_get_region_name(space_id), space_id,
 509                           acpi_ut_get_node_name(node), node, obj_desc));
 510
 511         /*
 512          * Install the handler
 513          *
 514          * At this point there is no existing handler. Just allocate the object
 515          * for the handler and link it into the list.
 516          */
 517         handler_obj =
 518             acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_ADDRESS_HANDLER);
 519         if (!handler_obj) {
 520                 status = AE_NO_MEMORY;
 521                 goto unlock_and_exit;
 522         }
 523
 524         /* Init handler obj */
 525
 526         handler_obj->address_space.space_id = (u8)space_id;
 527         handler_obj->address_space.handler_flags = flags;
 528         handler_obj->address_space.region_list = NULL;
 529         handler_obj->address_space.node = node;
 530         handler_obj->address_space.handler = handler;
 531         handler_obj->address_space.context = context;
 532         handler_obj->address_space.setup = setup;
 533
 534         /* Install at head of Device.address_space list */
 535
 536         handler_obj->address_space.next = obj_desc->common_notify.handler;
 537
 538         /*
 539          * The Device object is the first reference on the handler_obj.
 540          * Each region that uses the handler adds a reference.
 541          */
 542         obj_desc->common_notify.handler = handler_obj;
 543
 544         /*
 545          * Walk the namespace finding all of the regions this handler will
 546          * manage.
 547          *
 548          * Start at the device and search the branch toward the leaf nodes
 549          * until either the leaf is encountered or a device is detected that
 550          * has an address handler of the same type.
 551          *
 552          * In either case, back up and search down the remainder of the branch
 553          */
 554         status = acpi_ns_walk_namespace(ACPI_TYPE_ANY, node,
 555                                         ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
 556                                         acpi_ev_install_handler, NULL,
 557                                         handler_obj, NULL);
 558
 559 unlock_and_exit:
 560         return_ACPI_STATUS(status);
 561 }