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
  51 #define _COMPONENT          ACPI_NAMESPACE
  52 ACPI_MODULE_NAME("dspkginit")
  53
  54 /* Local prototypes */
  55 static void
  56 acpi_ds_resolve_package_element(union acpi_operand_object **element);
  57
  58 /*******************************************************************************
  59  *
  60  * FUNCTION:    acpi_ds_build_internal_package_obj
  61  *
  62  * PARAMETERS:  walk_state      - Current walk state
  63  *              op              - Parser object to be translated
  64  *              element_count   - Number of elements in the package - this is
  65  *                                the num_elements argument to Package()
  66  *              obj_desc_ptr    - Where the ACPI internal object is returned
  67  *
  68  * RETURN:      Status
  69  *
  70  * DESCRIPTION: Translate a parser Op package object to the equivalent
  71  *              namespace object
  72  *
  73  * NOTE: The number of elements in the package will be always be the num_elements
  74  * count, regardless of the number of elements in the package list. If
  75  * num_elements is smaller, only that many package list elements are used.
  76  * if num_elements is larger, the Package object is padded out with
  77  * objects of type Uninitialized (as per ACPI spec.)
  78  *
  79  * Even though the ASL compilers do not allow num_elements to be smaller
  80  * than the Package list length (for the fixed length package opcode), some
  81  * BIOS code modifies the AML on the fly to adjust the num_elements, and
  82  * this code compensates for that. This also provides compatibility with
  83  * other AML interpreters.
  84  *
  85  ******************************************************************************/
  86
  87 acpi_status
  88 acpi_ds_build_internal_package_obj(struct acpi_walk_state *walk_state,
  89                                    union acpi_parse_object *op,
  90                                    u32 element_count,
  91                                    union acpi_operand_object **obj_desc_ptr)
  92 {
  93         union acpi_parse_object *arg;
  94         union acpi_parse_object *parent;
  95         union acpi_operand_object *obj_desc = NULL;
  96         acpi_status status = AE_OK;
  97         u16 reference_count;
  98         u32 index;
  99         u32 i;
 100
 101         ACPI_FUNCTION_TRACE(ds_build_internal_package_obj);
 102
 103         /* Find the parent of a possibly nested package */
 104
 105         parent = op->common.parent;
 106         while ((parent->common.aml_opcode == AML_PACKAGE_OP) ||
 107                (parent->common.aml_opcode == AML_VARIABLE_PACKAGE_OP)) {
 108                 parent = parent->common.parent;
 109         }
 110
 111         /*
 112          * If we are evaluating a Named package object of the form:
 113          *      Name (xxxx, Package)
 114          * the package object already exists, otherwise it must be created.
 115          */
 116         obj_desc = *obj_desc_ptr;
 117         if (!obj_desc) {
 118                 obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_PACKAGE);
 119                 *obj_desc_ptr = obj_desc;
 120                 if (!obj_desc) {
 121                         return_ACPI_STATUS(AE_NO_MEMORY);
 122                 }
 123
 124                 obj_desc->package.node = parent->common.node;
 125         }
 126
 127         if (obj_desc->package.flags & AOPOBJ_DATA_VALID) {      /* Just in case */
 128                 return_ACPI_STATUS(AE_OK);
 129         }
 130
 131         /*
 132          * Allocate the element array (array of pointers to the individual
 133          * objects) based on the num_elements parameter. Add an extra pointer slot
 134          * so that the list is always null terminated.
 135          */
 136         obj_desc->package.elements = ACPI_ALLOCATE_ZEROED(((acpi_size)
 137                                                            element_count +
 138                                                            1) * sizeof(void *));
 139
 140         if (!obj_desc->package.elements) {
 141                 acpi_ut_delete_object_desc(obj_desc);
 142                 return_ACPI_STATUS(AE_NO_MEMORY);
 143         }
 144
 145         obj_desc->package.count = element_count;
 146         arg = op->common.value.arg;
 147         arg = arg->common.next;
 148
 149         if (arg) {
 150                 obj_desc->package.flags |= AOPOBJ_DATA_VALID;
 151         }
 152
 153         /*
 154          * Initialize the elements of the package, up to the num_elements count.
 155          * Package is automatically padded with uninitialized (NULL) elements
 156          * if num_elements is greater than the package list length. Likewise,
 157          * Package is truncated if num_elements is less than the list length.
 158          */
 159         for (i = 0; arg && (i < element_count); i++) {
 160                 if (arg->common.aml_opcode == AML_INT_RETURN_VALUE_OP) {
 161                         if (arg->common.node->type == ACPI_TYPE_METHOD) {
 162                                 /*
 163                                  * A method reference "looks" to the parser to be a method
 164                                  * invocation, so we special case it here
 165                                  */
 166                                 arg->common.aml_opcode = AML_INT_NAMEPATH_OP;
 167                                 status =
 168                                     acpi_ds_build_internal_object(walk_state,
 169                                                                   arg,
 170                                                                   &obj_desc->
 171                                                                   package.
 172                                                                   elements[i]);
 173                         } else {
 174                                 /* This package element is already built, just get it */
 175
 176                                 obj_desc->package.elements[i] =
 177                                     ACPI_CAST_PTR(union acpi_operand_object,
 178                                                   arg->common.node);
 179                         }
 180                 } else {
 181                         status =
 182                             acpi_ds_build_internal_object(walk_state, arg,
 183                                                           &obj_desc->package.
 184                                                           elements[i]);
 185                         if (status == AE_NOT_FOUND) {
 186                                 ACPI_ERROR((AE_INFO, "%-48s",
 187                                             "****DS namepath not found"));
 188                         }
 189
 190                         /*
 191                          * Initialize this package element. This function handles the
 192                          * resolution of named references within the package.
 193                          */
 194                         acpi_ds_init_package_element(0,
 195                                                      obj_desc->package.
 196                                                      elements[i], NULL,
 197                                                      &obj_desc->package.
 198                                                      elements[i]);
 199                 }
 200
 201                 if (*obj_desc_ptr) {
 202
 203                         /* Existing package, get existing reference count */
 204
 205                         reference_count =
 206                             (*obj_desc_ptr)->common.reference_count;
 207                         if (reference_count > 1) {
 208
 209                                 /* Make new element ref count match original ref count */
 210                                 /* TBD: Probably need an acpi_ut_add_references function */
 211
 212                                 for (index = 0;
 213                                      index < ((u32)reference_count - 1);
 214                                      index++) {
 215                                         acpi_ut_add_reference((obj_desc->
 216                                                                package.
 217                                                                elements[i]));
 218                                 }
 219                         }
 220                 }
 221
 222                 arg = arg->common.next;
 223         }
 224
 225         /* Check for match between num_elements and actual length of package_list */
 226
 227         if (arg) {
 228                 /*
 229                  * num_elements was exhausted, but there are remaining elements in
 230                  * the package_list. Truncate the package to num_elements.
 231                  *
 232                  * Note: technically, this is an error, from ACPI spec: "It is an
 233                  * error for NumElements to be less than the number of elements in
 234                  * the PackageList". However, we just print a message and no
 235                  * exception is returned. This provides compatibility with other
 236                  * ACPI implementations. Some firmware implementations will alter
 237                  * the num_elements on the fly, possibly creating this type of
 238                  * ill-formed package object.
 239                  */
 240                 while (arg) {
 241                         /*
 242                          * We must delete any package elements that were created earlier
 243                          * and are not going to be used because of the package truncation.
 244                          */
 245                         if (arg->common.node) {
 246                                 acpi_ut_remove_reference(ACPI_CAST_PTR
 247                                                          (union
 248                                                           acpi_operand_object,
 249                                                           arg->common.node));
 250                                 arg->common.node = NULL;
 251                         }
 252
 253                         /* Find out how many elements there really are */
 254
 255                         i++;
 256                         arg = arg->common.next;
 257                 }
 258
 259                 ACPI_INFO(("Actual Package length (%u) is larger than "
 260                            "NumElements field (%u), truncated",
 261                            i, element_count));
 262         } else if (i < element_count) {
 263                 /*
 264                  * Arg list (elements) was exhausted, but we did not reach
 265                  * num_elements count.
 266                  *
 267                  * Note: this is not an error, the package is padded out
 268                  * with NULLs.
 269                  */
 270                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 271                                   "Package List length (%u) smaller than NumElements "
 272                                   "count (%u), padded with null elements\n",
 273                                   i, element_count));
 274         }
 275
 276         obj_desc->package.flags |= AOPOBJ_DATA_VALID;
 277         op->common.node = ACPI_CAST_PTR(struct acpi_namespace_node, obj_desc);
 278         return_ACPI_STATUS(status);
 279 }
 280
 281 /*******************************************************************************
 282  *
 283  * FUNCTION:    acpi_ds_init_package_element
 284  *
 285  * PARAMETERS:  acpi_pkg_callback
 286  *
 287  * RETURN:      Status
 288  *
 289  * DESCRIPTION: Resolve a named reference element within a package object
 290  *
 291  ******************************************************************************/
 292
 293 acpi_status
 294 acpi_ds_init_package_element(u8 object_type,
 295                              union acpi_operand_object *source_object,
 296                              union acpi_generic_state *state, void *context)
 297 {
 298         union acpi_operand_object **element_ptr;
 299
 300         ACPI_FUNCTION_TRACE(ds_init_package_element);
 301
 302         if (!source_object) {
 303                 return_ACPI_STATUS(AE_OK);
 304         }
 305
 306         /*
 307          * The following code is a bit of a hack to workaround a (current)
 308          * limitation of the acpi_pkg_callback interface. We need a pointer
 309          * to the location within the element array because a new object
 310          * may be created and stored there.
 311          */
 312         if (context) {
 313
 314                 /* A direct call was made to this function */
 315
 316                 element_ptr = (union acpi_operand_object **)context;
 317         } else {
 318                 /* Call came from acpi_ut_walk_package_tree */
 319
 320                 element_ptr = state->pkg.this_target_obj;
 321         }
 322
 323         /* We are only interested in reference objects/elements */
 324
 325         if (source_object->common.type == ACPI_TYPE_LOCAL_REFERENCE) {
 326
 327                 /* Attempt to resolve the (named) reference to a namespace node */
 328
 329                 acpi_ds_resolve_package_element(element_ptr);
 330         } else if (source_object->common.type == ACPI_TYPE_PACKAGE) {
 331                 source_object->package.flags |= AOPOBJ_DATA_VALID;
 332         }
 333
 334         return_ACPI_STATUS(AE_OK);
 335 }
 336
 337 /*******************************************************************************
 338  *
 339  * FUNCTION:    acpi_ds_resolve_package_element
 340  *
 341  * PARAMETERS:  element_ptr         - Pointer to a reference object
 342  *
 343  * RETURN:      Possible new element is stored to the indirect element_ptr
 344  *
 345  * DESCRIPTION: Resolve a package element that is a reference to a named
 346  *              object.
 347  *
 348  ******************************************************************************/
 349
 350 static void
 351 acpi_ds_resolve_package_element(union acpi_operand_object **element_ptr)
 352 {
 353         acpi_status status;
 354         union acpi_generic_state scope_info;
 355         union acpi_operand_object *element = *element_ptr;
 356         struct acpi_namespace_node *resolved_node;
 357         struct acpi_namespace_node *original_node;
 358         char *external_path = NULL;
 359         acpi_object_type type;
 360
 361         ACPI_FUNCTION_TRACE(ds_resolve_package_element);
 362
 363         /* Check if reference element is already resolved */
 364
 365         if (element->reference.resolved) {
 366                 return_VOID;
 367         }
 368
 369         /* Element must be a reference object of correct type */
 370
 371         scope_info.scope.node = element->reference.node;        /* Prefix node */
 372
 373         status = acpi_ns_lookup(&scope_info, (char *)element->reference.aml,    /* Pointer to AML path */
 374                                 ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
 375                                 ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE,
 376                                 NULL, &resolved_node);
 377         if (ACPI_FAILURE(status)) {
 378                 status = acpi_ns_externalize_name(ACPI_UINT32_MAX,
 379                                                   (char *)element->reference.
 380                                                   aml, NULL, &external_path);
 381
 382                 ACPI_EXCEPTION((AE_INFO, status,
 383                                 "Could not find/resolve named package element: %s",
 384                                 external_path));
 385
 386                 ACPI_FREE(external_path);
 387                 *element_ptr = NULL;
 388                 return_VOID;
 389         } else if (resolved_node->type == ACPI_TYPE_ANY) {
 390
 391                 /* Named reference not resolved, return a NULL package element */
 392
 393                 ACPI_ERROR((AE_INFO,
 394                             "Could not resolve named package element [%4.4s] in [%4.4s]",
 395                             resolved_node->name.ascii,
 396                             scope_info.scope.node->name.ascii));
 397                 *element_ptr = NULL;
 398                 return_VOID;
 399         }
 400 #if 0
 401         else if (resolved_node->flags & ANOBJ_TEMPORARY) {
 402                 /*
 403                  * A temporary node found here indicates that the reference is
 404                  * to a node that was created within this method. We are not
 405                  * going to allow it (especially if the package is returned
 406                  * from the method) -- the temporary node will be deleted out
 407                  * from under the method. (05/2017).
 408                  */
 409                 ACPI_ERROR((AE_INFO,
 410                             "Package element refers to a temporary name [%4.4s], "
 411                             "inserting a NULL element",
 412                             resolved_node->name.ascii));
 413                 *element_ptr = NULL;
 414                 return_VOID;
 415         }
 416 #endif
 417
 418         /*
 419          * Special handling for Alias objects. We need resolved_node to point
 420          * to the Alias target. This effectively "resolves" the alias.
 421          */
 422         if (resolved_node->type == ACPI_TYPE_LOCAL_ALIAS) {
 423                 resolved_node = ACPI_CAST_PTR(struct acpi_namespace_node,
 424                                               resolved_node->object);
 425         }
 426
 427         /* Update the reference object */
 428
 429         element->reference.resolved = TRUE;
 430         element->reference.node = resolved_node;
 431         type = element->reference.node->type;
 432
 433         /*
 434          * Attempt to resolve the node to a value before we insert it into
 435          * the package. If this is a reference to a common data type,
 436          * resolve it immediately. According to the ACPI spec, package
 437          * elements can only be "data objects" or method references.
 438          * Attempt to resolve to an Integer, Buffer, String or Package.
 439          * If cannot, return the named reference (for things like Devices,
 440          * Methods, etc.) Buffer Fields and Fields will resolve to simple
 441          * objects (int/buf/str/pkg).
 442          *
 443          * NOTE: References to things like Devices, Methods, Mutexes, etc.
 444          * will remain as named references. This behavior is not described
 445          * in the ACPI spec, but it appears to be an oversight.
 446          */
 447         original_node = resolved_node;
 448         status = acpi_ex_resolve_node_to_value(&resolved_node, NULL);
 449         if (ACPI_FAILURE(status)) {
 450                 return_VOID;
 451         }
 452 #if 0
 453 /* TBD - alias support */
 454         /*
 455          * Special handling for Alias objects. We need to setup the type
 456          * and the Op->Common.Node to point to the Alias target. Note,
 457          * Alias has at most one level of indirection internally.
 458          */
 459         type = op->common.node->type;
 460         if (type == ACPI_TYPE_LOCAL_ALIAS) {
 461                 type = obj_desc->common.type;
 462                 op->common.node = ACPI_CAST_PTR(struct acpi_namespace_node,
 463                                                 op->common.node->object);
 464         }
 465 #endif
 466
 467         switch (type) {
 468                 /*
 469                  * These object types are a result of named references, so we will
 470                  * leave them as reference objects. In other words, these types
 471                  * have no intrinsic "value".
 472                  */
 473         case ACPI_TYPE_DEVICE:
 474         case ACPI_TYPE_THERMAL:
 475         case ACPI_TYPE_METHOD:
 476                 break;
 477
 478         case ACPI_TYPE_MUTEX:
 479         case ACPI_TYPE_POWER:
 480         case ACPI_TYPE_PROCESSOR:
 481         case ACPI_TYPE_EVENT:
 482         case ACPI_TYPE_REGION:
 483
 484                 /* acpi_ex_resolve_node_to_value gave these an extra reference */
 485
 486                 acpi_ut_remove_reference(original_node->object);
 487                 break;
 488
 489         default:
 490                 /*
 491                  * For all other types - the node was resolved to an actual
 492                  * operand object with a value, return the object. Remove
 493                  * a reference on the existing object.
 494                  */
 495                 acpi_ut_remove_reference(element);
 496                 *element_ptr = (union acpi_operand_object *)resolved_node;
 497                 break;
 498         }
 499
 500         return_VOID;
 501 }