drivers/acpi/namespace/nsparse.c

   1 /******************************************************************************
   2  *
   3  * Module Name: nsparse - namespace interface to AML parser
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2006, R. Byron Moore
   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 <acpi/acnamesp.h>
  46 #include <acpi/acparser.h>
  47 #include <acpi/acdispat.h>
  48
  49 #define _COMPONENT          ACPI_NAMESPACE
  50 ACPI_MODULE_NAME("nsparse")
  51
  52 /*******************************************************************************
  53  *
  54  * FUNCTION:    ns_one_complete_parse
  55  *
  56  * PARAMETERS:  pass_number             - 1 or 2
  57  *              table_desc              - The table to be parsed.
  58  *
  59  * RETURN:      Status
  60  *
  61  * DESCRIPTION: Perform one complete parse of an ACPI/AML table.
  62  *
  63  ******************************************************************************/
  64 acpi_status
  65 acpi_ns_one_complete_parse(u8 pass_number, struct acpi_table_desc *table_desc)
  66 {
  67         union acpi_parse_object *parse_root;
  68         acpi_status status;
  69         struct acpi_walk_state *walk_state;
  70
  71         ACPI_FUNCTION_TRACE(ns_one_complete_parse);
  72
  73         /* Create and init a Root Node */
  74
  75         parse_root = acpi_ps_create_scope_op();
  76         if (!parse_root) {
  77                 return_ACPI_STATUS(AE_NO_MEMORY);
  78         }
  79
  80         /* Create and initialize a new walk state */
  81
  82         walk_state = acpi_ds_create_walk_state(table_desc->owner_id,
  83                                                NULL, NULL, NULL);
  84         if (!walk_state) {
  85                 acpi_ps_free_op(parse_root);
  86                 return_ACPI_STATUS(AE_NO_MEMORY);
  87         }
  88
  89         status = acpi_ds_init_aml_walk(walk_state, parse_root, NULL,
  90                                        table_desc->aml_start,
  91                                        table_desc->aml_length, NULL,
  92                                        pass_number);
  93         if (ACPI_FAILURE(status)) {
  94                 acpi_ds_delete_walk_state(walk_state);
  95                 return_ACPI_STATUS(status);
  96         }
  97
  98         /* Parse the AML */
  99
 100         ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "*PARSE* pass %d parse\n",
 101                           pass_number));
 102         status = acpi_ps_parse_aml(walk_state);
 103
 104         acpi_ps_delete_parse_tree(parse_root);
 105         return_ACPI_STATUS(status);
 106 }
 107
 108 /*******************************************************************************
 109  *
 110  * FUNCTION:    acpi_ns_parse_table
 111  *
 112  * PARAMETERS:  table_desc      - An ACPI table descriptor for table to parse
 113  *              start_node      - Where to enter the table into the namespace
 114  *
 115  * RETURN:      Status
 116  *
 117  * DESCRIPTION: Parse AML within an ACPI table and return a tree of ops
 118  *
 119  ******************************************************************************/
 120
 121 acpi_status
 122 acpi_ns_parse_table(struct acpi_table_desc *table_desc,
 123                     struct acpi_namespace_node *start_node)
 124 {
 125         acpi_status status;
 126
 127         ACPI_FUNCTION_TRACE(ns_parse_table);
 128
 129         /*
 130          * AML Parse, pass 1
 131          *
 132          * In this pass, we load most of the namespace.  Control methods
 133          * are not parsed until later.  A parse tree is not created.  Instead,
 134          * each Parser Op subtree is deleted when it is finished.  This saves
 135          * a great deal of memory, and allows a small cache of parse objects
 136          * to service the entire parse.  The second pass of the parse then
 137          * performs another complete parse of the AML..
 138          */
 139         ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "**** Start pass 1\n"));
 140         status = acpi_ns_one_complete_parse(1, table_desc);
 141         if (ACPI_FAILURE(status)) {
 142                 return_ACPI_STATUS(status);
 143         }
 144
 145         /*
 146          * AML Parse, pass 2
 147          *
 148          * In this pass, we resolve forward references and other things
 149          * that could not be completed during the first pass.
 150          * Another complete parse of the AML is performed, but the
 151          * overhead of this is compensated for by the fact that the
 152          * parse objects are all cached.
 153          */
 154         ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "**** Start pass 2\n"));
 155         status = acpi_ns_one_complete_parse(2, table_desc);
 156         if (ACPI_FAILURE(status)) {
 157                 return_ACPI_STATUS(status);
 158         }
 159
 160         return_ACPI_STATUS(status);
 161 }