drivers/acpi/acpica/dspkginit.c

   1 /******************************************************************************
   2  *
   3  * Module Name: dspkginit - Completion of deferred package initialization
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2018, 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 "acnamesp.h"
  47 #include "amlcode.h"
  48 #include "acdispat.h"
  49 #include "acinterp.h"
  50 #include "acparser.h"
  51
  52 #define _COMPONENT          ACPI_NAMESPACE
  53 ACPI_MODULE_NAME("dspkginit")
  54
  55 /* Local prototypes */
  56 static void
  57 acpi_ds_resolve_package_element(union acpi_operand_object **element);
  58
  59 /*******************************************************************************
  60  *
  61  * FUNCTION:    acpi_ds_build_internal_package_obj
  62  *
  63  * PARAMETERS:  walk_state      - Current walk state
  64  *              op              - Parser object to be translated
  65  *              element_count   - Number of elements in the package - this is
  66  *                                the num_elements argument to Package()
  67  *              obj_desc_ptr    - Where the ACPI internal object is returned
  68  *
  69  * RETURN:      Status
  70  *
  71  * DESCRIPTION: Translate a parser Op package object to the equivalent
  72  *              namespace object
  73  *
  74  * NOTE: The number of elements in the package will be always be the num_elements
  75  * count, regardless of the number of elements in the package list. If
  76  * num_elements is smaller, only that many package list elements are used.
  77  * if num_elements is larger, the Package object is padded out with
  78  * objects of type Uninitialized (as per ACPI spec.)
  79  *
  80  * Even though the ASL compilers do not allow num_elements to be smaller
  81  * than the Package list length (for the fixed length package opcode), some
  82  * BIOS code modifies the AML on the fly to adjust the num_elements, and
  83  * this code compensates for that. This also provides compatibility with
  84  * other AML interpreters.
  85  *
  86  ******************************************************************************/
  87
  88 acpi_status
  89 acpi_ds_build_internal_package_obj(struct acpi_walk_state *walk_state,
  90                                    union acpi_parse_object *op,
  91                                    u32 element_count,
  92                                    union acpi_operand_object **obj_desc_ptr)
  93 {
  94         union acpi_parse_object *arg;
  95         union acpi_parse_object *parent;
  96         union acpi_operand_object *obj_desc = NULL;
  97         acpi_status status = AE_OK;
  98         u8 module_level_code = FALSE;
  99         u16 reference_count;
 100         u32 index;
 101         u32 i;
 102
 103         ACPI_FUNCTION_TRACE(ds_build_internal_package_obj);
 104
 105         /* Check if we are executing module level code */
 106
 107         if (walk_state->parse_flags & ACPI_PARSE_MODULE_LEVEL) {
 108                 module_level_code = TRUE;
 109         }
 110
 111         /* Find the parent of a possibly nested package */
 112
 113         parent = op->common.parent;
 114         while ((parent->common.aml_opcode == AML_PACKAGE_OP) ||
 115                (parent->common.aml_opcode == AML_VARIABLE_PACKAGE_OP)) {
 116                 parent = parent->common.parent;
 117         }
 118
 119         /*
 120          * If we are evaluating a Named package object of the form:
 121          *      Name (xxxx, Package)
 122          * the package object already exists, otherwise it must be created.
 123          */
 124         obj_desc = *obj_desc_ptr;
 125         if (!obj_desc) {
 126                 obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_PACKAGE);
 127                 *obj_desc_ptr = obj_desc;
 128                 if (!obj_desc) {
 129                         return_ACPI_STATUS(AE_NO_MEMORY);
 130                 }
 131
 132                 obj_desc->package.node = parent->common.node;
 133         }
 134
 135         if (obj_desc->package.flags & AOPOBJ_DATA_VALID) {      /* Just in case */
 136                 return_ACPI_STATUS(AE_OK);
 137         }
 138
 139         /*
 140          * Allocate the element array (array of pointers to the individual
 141          * objects) if necessary. the count is based on the num_elements
 142          * parameter. Add an extra pointer slot so that the list is always
 143          * null terminated.
 144          */
 145         if (!obj_desc->package.elements) {
 146                 obj_desc->package.elements = ACPI_ALLOCATE_ZEROED(((acpi_size)
 147                                                                    element_count
 148                                                                    +
 149                                                                    1) *
 150                                                                   sizeof(void
 151                                                                          *));
 152
 153                 if (!obj_desc->package.elements) {
 154                         acpi_ut_delete_object_desc(obj_desc);
 155                         return_ACPI_STATUS(AE_NO_MEMORY);
 156                 }
 157
 158                 obj_desc->package.count = element_count;
 159         }
 160
 161         /* First arg is element count. Second arg begins the initializer list */
 162
 163         arg = op->common.value.arg;
 164         arg = arg->common.next;
 165
 166         /*
 167          * If we are executing module-level code, we will defer the
 168          * full resolution of the package elements in order to support
 169          * forward references from the elements. This provides
 170          * compatibility with other ACPI implementations.
 171          */
 172         if (module_level_code) {
 173                 obj_desc->package.aml_start = walk_state->aml;
 174                 obj_desc->package.aml_length = 0;
 175
 176                 ACPI_DEBUG_PRINT_RAW((ACPI_DB_PARSE,
 177                                       "%s: Deferring resolution of Package elements\n",
 178                                       ACPI_GET_FUNCTION_NAME));
 179         }
 180
 181         /*
 182          * Initialize the elements of the package, up to the num_elements count.
 183          * Package is automatically padded with uninitialized (NULL) elements
 184          * if num_elements is greater than the package list length. Likewise,
 185          * Package is truncated if num_elements is less than the list length.
 186          */
 187         for (i = 0; arg && (i < element_count); i++) {
 188                 if (arg->common.aml_opcode == AML_INT_RETURN_VALUE_OP) {
 189                         if (arg->common.node->type == ACPI_TYPE_METHOD) {
 190                                 /*
 191                                  * A method reference "looks" to the parser to be a method
 192                                  * invocation, so we special case it here
 193                                  */
 194                                 arg->common.aml_opcode = AML_INT_NAMEPATH_OP;
 195                                 status =
 196                                     acpi_ds_build_internal_object(walk_state,
 197                                                                   arg,
 198                                                                   &obj_desc->
 199                                                                   package.
 200                                                                   elements[i]);
 201                         } else {
 202                                 /* This package element is already built, just get it */
 203
 204                                 obj_desc->package.elements[i] =
 205                                     ACPI_CAST_PTR(union acpi_operand_object,
 206                                                   arg->common.node);
 207                         }
 208                 } else {
 209                         status =
 210                             acpi_ds_build_internal_object(walk_state, arg,
 211                                                           &obj_desc->package.
 212                                                           elements[i]);
 213                         if (status == AE_NOT_FOUND) {
 214                                 ACPI_ERROR((AE_INFO, "%-48s",
 215                                             "****DS namepath not found"));
 216                         }
 217
 218                         if (!module_level_code) {
 219                                 /*
 220                                  * Initialize this package element. This function handles the
 221                                  * resolution of named references within the package.
 222                                  * Forward references from module-level code are deferred
 223                                  * until all ACPI tables are loaded.
 224                                  */
 225                                 acpi_ds_init_package_element(0,
 226                                                              obj_desc->package.
 227                                                              elements[i], NULL,
 228                                                              &obj_desc->package.
 229                                                              elements[i]);
 230                         }
 231                 }
 232
 233                 if (*obj_desc_ptr) {
 234
 235                         /* Existing package, get existing reference count */
 236
 237                         reference_count =
 238                             (*obj_desc_ptr)->common.reference_count;
 239                         if (reference_count > 1) {
 240
 241                                 /* Make new element ref count match original ref count */
 242                                 /* TBD: Probably need an acpi_ut_add_references function */
 243
 244                                 for (index = 0;
 245                                      index < ((u32)reference_count - 1);
 246                                      index++) {
 247                                         acpi_ut_add_reference((obj_desc->
 248                                                                package.
 249                                                                elements[i]));
 250                                 }
 251                         }
 252                 }
 253
 254                 arg = arg->common.next;
 255         }
 256
 257         /* Check for match between num_elements and actual length of package_list */
 258
 259         if (arg) {
 260                 /*
 261                  * num_elements was exhausted, but there are remaining elements in
 262                  * the package_list. Truncate the package to num_elements.
 263                  *
 264                  * Note: technically, this is an error, from ACPI spec: "It is an
 265                  * error for NumElements to be less than the number of elements in
 266                  * the PackageList". However, we just print a message and no
 267                  * exception is returned. This provides compatibility with other
 268                  * ACPI implementations. Some firmware implementations will alter
 269                  * the num_elements on the fly, possibly creating this type of
 270                  * ill-formed package object.
 271                  */
 272                 while (arg) {
 273                         /*
 274                          * We must delete any package elements that were created earlier
 275                          * and are not going to be used because of the package truncation.
 276                          */
 277                         if (arg->common.node) {
 278                                 acpi_ut_remove_reference(ACPI_CAST_PTR
 279                                                          (union
 280                                                           acpi_operand_object,
 281                                                           arg->common.node));
 282                                 arg->common.node = NULL;
 283                         }
 284
 285                         /* Find out how many elements there really are */
 286
 287                         i++;
 288                         arg = arg->common.next;
 289                 }
 290
 291                 ACPI_INFO(("Actual Package length (%u) is larger than "
 292                            "NumElements field (%u), truncated",
 293                            i, element_count));
 294         } else if (i < element_count) {
 295                 /*
 296                  * Arg list (elements) was exhausted, but we did not reach
 297                  * num_elements count.
 298                  *
 299                  * Note: this is not an error, the package is padded out
 300                  * with NULLs as per the ACPI specification.
 301                  */
 302                 ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO,
 303                                       "%s: Package List length (%u) smaller than NumElements "
 304                                       "count (%u), padded with null elements\n",
 305                                       ACPI_GET_FUNCTION_NAME, i,
 306                                       element_count));
 307         }
 308
 309         /* Module-level packages will be resolved later */
 310
 311         if (!module_level_code) {
 312                 obj_desc->package.flags |= AOPOBJ_DATA_VALID;
 313         }
 314
 315         op->common.node = ACPI_CAST_PTR(struct acpi_namespace_node, obj_desc);
 316         return_ACPI_STATUS(status);
 317 }
 318
 319 /*******************************************************************************
 320  *
 321  * FUNCTION:    acpi_ds_init_package_element
 322  *
 323  * PARAMETERS:  acpi_pkg_callback
 324  *
 325  * RETURN:      Status
 326  *
 327  * DESCRIPTION: Resolve a named reference element within a package object
 328  *
 329  ******************************************************************************/
 330
 331 acpi_status
 332 acpi_ds_init_package_element(u8 object_type,
 333                              union acpi_operand_object *source_object,
 334                              union acpi_generic_state *state, void *context)
 335 {
 336         union acpi_operand_object **element_ptr;
 337
 338         ACPI_FUNCTION_TRACE(ds_init_package_element);
 339
 340         if (!source_object) {
 341                 return_ACPI_STATUS(AE_OK);
 342         }
 343
 344         /*
 345          * The following code is a bit of a hack to workaround a (current)
 346          * limitation of the acpi_pkg_callback interface. We need a pointer
 347          * to the location within the element array because a new object
 348          * may be created and stored there.
 349          */
 350         if (context) {
 351
 352                 /* A direct call was made to this function */
 353
 354                 element_ptr = (union acpi_operand_object **)context;
 355         } else {
 356                 /* Call came from acpi_ut_walk_package_tree */
 357
 358                 element_ptr = state->pkg.this_target_obj;
 359         }
 360
 361         /* We are only interested in reference objects/elements */
 362
 363         if (source_object->common.type == ACPI_TYPE_LOCAL_REFERENCE) {
 364
 365                 /* Attempt to resolve the (named) reference to a namespace node */
 366
 367                 acpi_ds_resolve_package_element(element_ptr);
 368         } else if (source_object->common.type == ACPI_TYPE_PACKAGE) {
 369                 source_object->package.flags |= AOPOBJ_DATA_VALID;
 370         }
 371
 372         return_ACPI_STATUS(AE_OK);
 373 }
 374
 375 /*******************************************************************************
 376  *
 377  * FUNCTION:    acpi_ds_resolve_package_element
 378  *
 379  * PARAMETERS:  element_ptr         - Pointer to a reference object
 380  *
 381  * RETURN:      Possible new element is stored to the indirect element_ptr
 382  *
 383  * DESCRIPTION: Resolve a package element that is a reference to a named
 384  *              object.
 385  *
 386  ******************************************************************************/
 387
 388 static void
 389 acpi_ds_resolve_package_element(union acpi_operand_object **element_ptr)
 390 {
 391         acpi_status status;
 392         union acpi_generic_state scope_info;
 393         union acpi_operand_object *element = *element_ptr;
 394         struct acpi_namespace_node *resolved_node;
 395         struct acpi_namespace_node *original_node;
 396         char *external_path = NULL;
 397         acpi_object_type type;
 398
 399         ACPI_FUNCTION_TRACE(ds_resolve_package_element);
 400
 401         /* Check if reference element is already resolved */
 402
 403         if (element->reference.resolved) {
 404                 ACPI_DEBUG_PRINT_RAW((ACPI_DB_PARSE,
 405                                       "%s: Package element is already resolved\n",
 406                                       ACPI_GET_FUNCTION_NAME));
 407
 408                 return_VOID;
 409         }
 410
 411         /* Element must be a reference object of correct type */
 412
 413         scope_info.scope.node = element->reference.node;        /* Prefix node */
 414
 415         status = acpi_ns_lookup(&scope_info, (char *)element->reference.aml,    /* Pointer to AML path */
 416                                 ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
 417                                 ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE,
 418                                 NULL, &resolved_node);
 419         if (ACPI_FAILURE(status)) {
 420                 status = acpi_ns_externalize_name(ACPI_UINT32_MAX,
 421                                                   (char *)element->reference.
 422                                                   aml, NULL, &external_path);
 423
 424                 ACPI_EXCEPTION((AE_INFO, status,
 425                                 "Could not find/resolve named package element: %s",
 426                                 external_path));
 427
 428                 /* Not found, set the element to NULL */
 429
 430                 ACPI_FREE(external_path);
 431                 acpi_ut_remove_reference(*element_ptr);
 432                 *element_ptr = NULL;
 433                 return_VOID;
 434         } else if (resolved_node->type == ACPI_TYPE_ANY) {
 435
 436                 /* Named reference not resolved, return a NULL package element */
 437
 438                 ACPI_ERROR((AE_INFO,
 439                             "Could not resolve named package element [%4.4s] in [%4.4s]",
 440                             resolved_node->name.ascii,
 441                             scope_info.scope.node->name.ascii));
 442                 *element_ptr = NULL;
 443                 return_VOID;
 444         }
 445
 446         /*
 447          * Special handling for Alias objects. We need resolved_node to point
 448          * to the Alias target. This effectively "resolves" the alias.
 449          */
 450         if (resolved_node->type == ACPI_TYPE_LOCAL_ALIAS) {
 451                 resolved_node = ACPI_CAST_PTR(struct acpi_namespace_node,
 452                                               resolved_node->object);
 453         }
 454
 455         /* Update the reference object */
 456
 457         element->reference.resolved = TRUE;
 458         element->reference.node = resolved_node;
 459         type = element->reference.node->type;
 460
 461         /*
 462          * Attempt to resolve the node to a value before we insert it into
 463          * the package. If this is a reference to a common data type,
 464          * resolve it immediately. According to the ACPI spec, package
 465          * elements can only be "data objects" or method references.
 466          * Attempt to resolve to an Integer, Buffer, String or Package.
 467          * If cannot, return the named reference (for things like Devices,
 468          * Methods, etc.) Buffer Fields and Fields will resolve to simple
 469          * objects (int/buf/str/pkg).
 470          *
 471          * NOTE: References to things like Devices, Methods, Mutexes, etc.
 472          * will remain as named references. This behavior is not described
 473          * in the ACPI spec, but it appears to be an oversight.
 474          */
 475         original_node = resolved_node;
 476         status = acpi_ex_resolve_node_to_value(&resolved_node, NULL);
 477         if (ACPI_FAILURE(status)) {
 478                 return_VOID;
 479         }
 480
 481         switch (type) {
 482                 /*
 483                  * These object types are a result of named references, so we will
 484                  * leave them as reference objects. In other words, these types
 485                  * have no intrinsic "value".
 486                  */
 487         case ACPI_TYPE_DEVICE:
 488         case ACPI_TYPE_THERMAL:
 489         case ACPI_TYPE_METHOD:
 490                 break;
 491
 492         case ACPI_TYPE_MUTEX:
 493         case ACPI_TYPE_POWER:
 494         case ACPI_TYPE_PROCESSOR:
 495         case ACPI_TYPE_EVENT:
 496         case ACPI_TYPE_REGION:
 497
 498                 /* acpi_ex_resolve_node_to_value gave these an extra reference */
 499
 500                 acpi_ut_remove_reference(original_node->object);
 501                 break;
 502
 503         default:
 504                 /*
 505                  * For all other types - the node was resolved to an actual
 506                  * operand object with a value, return the object. Remove
 507                  * a reference on the existing object.
 508                  */
 509                 acpi_ut_remove_reference(element);
 510                 *element_ptr = (union acpi_operand_object *)resolved_node;
 511                 break;
 512         }
 513
 514         return_VOID;
 515 }