drivers/acpi/acpica/dspkginit.c

   1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
   2 /******************************************************************************
   3  *
   4  * Module Name: dspkginit - Completion of deferred package initialization
   5  *
   6  * Copyright (C) 2000 - 2018, Intel Corp.
   7  *
   8  *****************************************************************************/
   9
  10 #include <acpi/acpi.h>
  11 #include "accommon.h"
  12 #include "acnamesp.h"
  13 #include "amlcode.h"
  14 #include "acdispat.h"
  15 #include "acinterp.h"
  16 #include "acparser.h"
  17
  18 #define _COMPONENT          ACPI_NAMESPACE
  19 ACPI_MODULE_NAME("dspkginit")
  20
  21 /* Local prototypes */
  22 static void
  23 acpi_ds_resolve_package_element(union acpi_operand_object **element);
  24
  25 /*******************************************************************************
  26  *
  27  * FUNCTION:    acpi_ds_build_internal_package_obj
  28  *
  29  * PARAMETERS:  walk_state      - Current walk state
  30  *              op              - Parser object to be translated
  31  *              element_count   - Number of elements in the package - this is
  32  *                                the num_elements argument to Package()
  33  *              obj_desc_ptr    - Where the ACPI internal object is returned
  34  *
  35  * RETURN:      Status
  36  *
  37  * DESCRIPTION: Translate a parser Op package object to the equivalent
  38  *              namespace object
  39  *
  40  * NOTE: The number of elements in the package will be always be the num_elements
  41  * count, regardless of the number of elements in the package list. If
  42  * num_elements is smaller, only that many package list elements are used.
  43  * if num_elements is larger, the Package object is padded out with
  44  * objects of type Uninitialized (as per ACPI spec.)
  45  *
  46  * Even though the ASL compilers do not allow num_elements to be smaller
  47  * than the Package list length (for the fixed length package opcode), some
  48  * BIOS code modifies the AML on the fly to adjust the num_elements, and
  49  * this code compensates for that. This also provides compatibility with
  50  * other AML interpreters.
  51  *
  52  ******************************************************************************/
  53
  54 acpi_status
  55 acpi_ds_build_internal_package_obj(struct acpi_walk_state *walk_state,
  56                                    union acpi_parse_object *op,
  57                                    u32 element_count,
  58                                    union acpi_operand_object **obj_desc_ptr)
  59 {
  60         union acpi_parse_object *arg;
  61         union acpi_parse_object *parent;
  62         union acpi_operand_object *obj_desc = NULL;
  63         acpi_status status = AE_OK;
  64         u8 module_level_code = FALSE;
  65         u16 reference_count;
  66         u32 index;
  67         u32 i;
  68
  69         ACPI_FUNCTION_TRACE(ds_build_internal_package_obj);
  70
  71         /* Check if we are executing module level code */
  72
  73         if (walk_state->parse_flags & ACPI_PARSE_MODULE_LEVEL) {
  74                 module_level_code = TRUE;
  75         }
  76
  77         /* Find the parent of a possibly nested package */
  78
  79         parent = op->common.parent;
  80         while ((parent->common.aml_opcode == AML_PACKAGE_OP) ||
  81                (parent->common.aml_opcode == AML_VARIABLE_PACKAGE_OP)) {
  82                 parent = parent->common.parent;
  83         }
  84
  85         /*
  86          * If we are evaluating a Named package object of the form:
  87          *      Name (xxxx, Package)
  88          * the package object already exists, otherwise it must be created.
  89          */
  90         obj_desc = *obj_desc_ptr;
  91         if (!obj_desc) {
  92                 obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_PACKAGE);
  93                 *obj_desc_ptr = obj_desc;
  94                 if (!obj_desc) {
  95                         return_ACPI_STATUS(AE_NO_MEMORY);
  96                 }
  97
  98                 obj_desc->package.node = parent->common.node;
  99         }
 100
 101         if (obj_desc->package.flags & AOPOBJ_DATA_VALID) {      /* Just in case */
 102                 return_ACPI_STATUS(AE_OK);
 103         }
 104
 105         /*
 106          * Allocate the element array (array of pointers to the individual
 107          * objects) if necessary. the count is based on the num_elements
 108          * parameter. Add an extra pointer slot so that the list is always
 109          * null terminated.
 110          */
 111         if (!obj_desc->package.elements) {
 112                 obj_desc->package.elements = ACPI_ALLOCATE_ZEROED(((acpi_size)
 113                                                                    element_count
 114                                                                    +
 115                                                                    1) *
 116                                                                   sizeof(void
 117                                                                          *));
 118
 119                 if (!obj_desc->package.elements) {
 120                         acpi_ut_delete_object_desc(obj_desc);
 121                         return_ACPI_STATUS(AE_NO_MEMORY);
 122                 }
 123
 124                 obj_desc->package.count = element_count;
 125         }
 126
 127         /* First arg is element count. Second arg begins the initializer list */
 128
 129         arg = op->common.value.arg;
 130         arg = arg->common.next;
 131
 132         /*
 133          * If we are executing module-level code, we will defer the
 134          * full resolution of the package elements in order to support
 135          * forward references from the elements. This provides
 136          * compatibility with other ACPI implementations.
 137          */
 138         if (module_level_code) {
 139                 obj_desc->package.aml_start = walk_state->aml;
 140                 obj_desc->package.aml_length = 0;
 141
 142                 ACPI_DEBUG_PRINT_RAW((ACPI_DB_PARSE,
 143                                       "%s: Deferring resolution of Package elements\n",
 144                                       ACPI_GET_FUNCTION_NAME));
 145         }
 146
 147         /*
 148          * Initialize the elements of the package, up to the num_elements count.
 149          * Package is automatically padded with uninitialized (NULL) elements
 150          * if num_elements is greater than the package list length. Likewise,
 151          * Package is truncated if num_elements is less than the list length.
 152          */
 153         for (i = 0; arg && (i < element_count); i++) {
 154                 if (arg->common.aml_opcode == AML_INT_RETURN_VALUE_OP) {
 155                         if (arg->common.node->type == ACPI_TYPE_METHOD) {
 156                                 /*
 157                                  * A method reference "looks" to the parser to be a method
 158                                  * invocation, so we special case it here
 159                                  */
 160                                 arg->common.aml_opcode = AML_INT_NAMEPATH_OP;
 161                                 status =
 162                                     acpi_ds_build_internal_object(walk_state,
 163                                                                   arg,
 164                                                                   &obj_desc->
 165                                                                   package.
 166                                                                   elements[i]);
 167                         } else {
 168                                 /* This package element is already built, just get it */
 169
 170                                 obj_desc->package.elements[i] =
 171                                     ACPI_CAST_PTR(union acpi_operand_object,
 172                                                   arg->common.node);
 173                         }
 174                 } else {
 175                         status =
 176                             acpi_ds_build_internal_object(walk_state, arg,
 177                                                           &obj_desc->package.
 178                                                           elements[i]);
 179                         if (status == AE_NOT_FOUND) {
 180                                 ACPI_ERROR((AE_INFO, "%-48s",
 181                                             "****DS namepath not found"));
 182                         }
 183
 184                         if (!module_level_code) {
 185                                 /*
 186                                  * Initialize this package element. This function handles the
 187                                  * resolution of named references within the package.
 188                                  * Forward references from module-level code are deferred
 189                                  * until all ACPI tables are loaded.
 190                                  */
 191                                 acpi_ds_init_package_element(0,
 192                                                              obj_desc->package.
 193                                                              elements[i], NULL,
 194                                                              &obj_desc->package.
 195                                                              elements[i]);
 196                         }
 197                 }
 198
 199                 if (*obj_desc_ptr) {
 200
 201                         /* Existing package, get existing reference count */
 202
 203                         reference_count =
 204                             (*obj_desc_ptr)->common.reference_count;
 205                         if (reference_count > 1) {
 206
 207                                 /* Make new element ref count match original ref count */
 208                                 /* TBD: Probably need an acpi_ut_add_references function */
 209
 210                                 for (index = 0;
 211                                      index < ((u32)reference_count - 1);
 212                                      index++) {
 213                                         acpi_ut_add_reference((obj_desc->
 214                                                                package.
 215                                                                elements[i]));
 216                                 }
 217                         }
 218                 }
 219
 220                 arg = arg->common.next;
 221         }
 222
 223         /* Check for match between num_elements and actual length of package_list */
 224
 225         if (arg) {
 226                 /*
 227                  * num_elements was exhausted, but there are remaining elements in
 228                  * the package_list. Truncate the package to num_elements.
 229                  *
 230                  * Note: technically, this is an error, from ACPI spec: "It is an
 231                  * error for NumElements to be less than the number of elements in
 232                  * the PackageList". However, we just print a message and no
 233                  * exception is returned. This provides compatibility with other
 234                  * ACPI implementations. Some firmware implementations will alter
 235                  * the num_elements on the fly, possibly creating this type of
 236                  * ill-formed package object.
 237                  */
 238                 while (arg) {
 239                         /*
 240                          * We must delete any package elements that were created earlier
 241                          * and are not going to be used because of the package truncation.
 242                          */
 243                         if (arg->common.node) {
 244                                 acpi_ut_remove_reference(ACPI_CAST_PTR
 245                                                          (union
 246                                                           acpi_operand_object,
 247                                                           arg->common.node));
 248                                 arg->common.node = NULL;
 249                         }
 250
 251                         /* Find out how many elements there really are */
 252
 253                         i++;
 254                         arg = arg->common.next;
 255                 }
 256
 257                 ACPI_INFO(("Actual Package length (%u) is larger than "
 258                            "NumElements field (%u), truncated",
 259                            i, element_count));
 260         } else if (i < element_count) {
 261                 /*
 262                  * Arg list (elements) was exhausted, but we did not reach
 263                  * num_elements count.
 264                  *
 265                  * Note: this is not an error, the package is padded out
 266                  * with NULLs as per the ACPI specification.
 267                  */
 268                 ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO,
 269                                       "%s: Package List length (%u) smaller than NumElements "
 270                                       "count (%u), padded with null elements\n",
 271                                       ACPI_GET_FUNCTION_NAME, i,
 272                                       element_count));
 273         }
 274
 275         /* Module-level packages will be resolved later */
 276
 277         if (!module_level_code) {
 278                 obj_desc->package.flags |= AOPOBJ_DATA_VALID;
 279         }
 280
 281         op->common.node = ACPI_CAST_PTR(struct acpi_namespace_node, obj_desc);
 282         return_ACPI_STATUS(status);
 283 }
 284
 285 /*******************************************************************************
 286  *
 287  * FUNCTION:    acpi_ds_init_package_element
 288  *
 289  * PARAMETERS:  acpi_pkg_callback
 290  *
 291  * RETURN:      Status
 292  *
 293  * DESCRIPTION: Resolve a named reference element within a package object
 294  *
 295  ******************************************************************************/
 296
 297 acpi_status
 298 acpi_ds_init_package_element(u8 object_type,
 299                              union acpi_operand_object *source_object,
 300                              union acpi_generic_state *state, void *context)
 301 {
 302         union acpi_operand_object **element_ptr;
 303
 304         ACPI_FUNCTION_TRACE(ds_init_package_element);
 305
 306         if (!source_object) {
 307                 return_ACPI_STATUS(AE_OK);
 308         }
 309
 310         /*
 311          * The following code is a bit of a hack to workaround a (current)
 312          * limitation of the acpi_pkg_callback interface. We need a pointer
 313          * to the location within the element array because a new object
 314          * may be created and stored there.
 315          */
 316         if (context) {
 317
 318                 /* A direct call was made to this function */
 319
 320                 element_ptr = (union acpi_operand_object **)context;
 321         } else {
 322                 /* Call came from acpi_ut_walk_package_tree */
 323
 324                 element_ptr = state->pkg.this_target_obj;
 325         }
 326
 327         /* We are only interested in reference objects/elements */
 328
 329         if (source_object->common.type == ACPI_TYPE_LOCAL_REFERENCE) {
 330
 331                 /* Attempt to resolve the (named) reference to a namespace node */
 332
 333                 acpi_ds_resolve_package_element(element_ptr);
 334         } else if (source_object->common.type == ACPI_TYPE_PACKAGE) {
 335                 source_object->package.flags |= AOPOBJ_DATA_VALID;
 336         }
 337
 338         return_ACPI_STATUS(AE_OK);
 339 }
 340
 341 /*******************************************************************************
 342  *
 343  * FUNCTION:    acpi_ds_resolve_package_element
 344  *
 345  * PARAMETERS:  element_ptr         - Pointer to a reference object
 346  *
 347  * RETURN:      Possible new element is stored to the indirect element_ptr
 348  *
 349  * DESCRIPTION: Resolve a package element that is a reference to a named
 350  *              object.
 351  *
 352  ******************************************************************************/
 353
 354 static void
 355 acpi_ds_resolve_package_element(union acpi_operand_object **element_ptr)
 356 {
 357         acpi_status status;
 358         acpi_status status2;
 359         union acpi_generic_state scope_info;
 360         union acpi_operand_object *element = *element_ptr;
 361         struct acpi_namespace_node *resolved_node;
 362         struct acpi_namespace_node *original_node;
 363         char *external_path = "";
 364         acpi_object_type type;
 365
 366         ACPI_FUNCTION_TRACE(ds_resolve_package_element);
 367
 368         /* Check if reference element is already resolved */
 369
 370         if (element->reference.resolved) {
 371                 ACPI_DEBUG_PRINT_RAW((ACPI_DB_PARSE,
 372                                       "%s: Package element is already resolved\n",
 373                                       ACPI_GET_FUNCTION_NAME));
 374
 375                 return_VOID;
 376         }
 377
 378         /* Element must be a reference object of correct type */
 379
 380         scope_info.scope.node = element->reference.node;        /* Prefix node */
 381
 382         status = acpi_ns_lookup(&scope_info, (char *)element->reference.aml,
 383                                 ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
 384                                 ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE,
 385                                 NULL, &resolved_node);
 386         if (ACPI_FAILURE(status)) {
 387                 if ((status == AE_NOT_FOUND)
 388                     && acpi_gbl_ignore_package_resolution_errors) {
 389                         /*
 390                          * Optionally be silent about the NOT_FOUND case for the referenced
 391                          * name. Although this is potentially a serious problem,
 392                          * it can generate a lot of noise/errors on platforms whose
 393                          * firmware carries around a bunch of unused Package objects.
 394                          * To disable these errors, set this global to TRUE:
 395                          *     acpi_gbl_ignore_package_resolution_errors
 396                          *
 397                          * If the AML actually tries to use such a package, the unresolved
 398                          * element(s) will be replaced with NULL elements.
 399                          */
 400
 401                         /* Referenced name not found, set the element to NULL */
 402
 403                         acpi_ut_remove_reference(*element_ptr);
 404                         *element_ptr = NULL;
 405                         return_VOID;
 406                 }
 407
 408                 status2 = acpi_ns_externalize_name(ACPI_UINT32_MAX,
 409                                                    (char *)element->reference.
 410                                                    aml, NULL, &external_path);
 411
 412                 ACPI_EXCEPTION((AE_INFO, status,
 413                                 "While resolving a named reference package element - %s",
 414                                 external_path));
 415                 if (ACPI_SUCCESS(status2)) {
 416                         ACPI_FREE(external_path);
 417                 }
 418
 419                 /* Could not resolve name, set the element to NULL */
 420
 421                 acpi_ut_remove_reference(*element_ptr);
 422                 *element_ptr = NULL;
 423                 return_VOID;
 424         } else if (resolved_node->type == ACPI_TYPE_ANY) {
 425
 426                 /* Named reference not resolved, return a NULL package element */
 427
 428                 ACPI_ERROR((AE_INFO,
 429                             "Could not resolve named package element [%4.4s] in [%4.4s]",
 430                             resolved_node->name.ascii,
 431                             scope_info.scope.node->name.ascii));
 432                 *element_ptr = NULL;
 433                 return_VOID;
 434         }
 435
 436         /*
 437          * Special handling for Alias objects. We need resolved_node to point
 438          * to the Alias target. This effectively "resolves" the alias.
 439          */
 440         if (resolved_node->type == ACPI_TYPE_LOCAL_ALIAS) {
 441                 resolved_node = ACPI_CAST_PTR(struct acpi_namespace_node,
 442                                               resolved_node->object);
 443         }
 444
 445         /* Update the reference object */
 446
 447         element->reference.resolved = TRUE;
 448         element->reference.node = resolved_node;
 449         type = element->reference.node->type;
 450
 451         /*
 452          * Attempt to resolve the node to a value before we insert it into
 453          * the package. If this is a reference to a common data type,
 454          * resolve it immediately. According to the ACPI spec, package
 455          * elements can only be "data objects" or method references.
 456          * Attempt to resolve to an Integer, Buffer, String or Package.
 457          * If cannot, return the named reference (for things like Devices,
 458          * Methods, etc.) Buffer Fields and Fields will resolve to simple
 459          * objects (int/buf/str/pkg).
 460          *
 461          * NOTE: References to things like Devices, Methods, Mutexes, etc.
 462          * will remain as named references. This behavior is not described
 463          * in the ACPI spec, but it appears to be an oversight.
 464          */
 465         original_node = resolved_node;
 466         status = acpi_ex_resolve_node_to_value(&resolved_node, NULL);
 467         if (ACPI_FAILURE(status)) {
 468                 return_VOID;
 469         }
 470
 471         switch (type) {
 472                 /*
 473                  * These object types are a result of named references, so we will
 474                  * leave them as reference objects. In other words, these types
 475                  * have no intrinsic "value".
 476                  */
 477         case ACPI_TYPE_DEVICE:
 478         case ACPI_TYPE_THERMAL:
 479         case ACPI_TYPE_METHOD:
 480                 break;
 481
 482         case ACPI_TYPE_MUTEX:
 483         case ACPI_TYPE_POWER:
 484         case ACPI_TYPE_PROCESSOR:
 485         case ACPI_TYPE_EVENT:
 486         case ACPI_TYPE_REGION:
 487
 488                 /* acpi_ex_resolve_node_to_value gave these an extra reference */
 489
 490                 acpi_ut_remove_reference(original_node->object);
 491                 break;
 492
 493         default:
 494                 /*
 495                  * For all other types - the node was resolved to an actual
 496                  * operand object with a value, return the object. Remove
 497                  * a reference on the existing object.
 498                  */
 499                 acpi_ut_remove_reference(element);
 500                 *element_ptr = (union acpi_operand_object *)resolved_node;
 501                 break;
 502         }
 503
 504         return_VOID;
 505 }