drivers/acpi/namespace/nsparse.c

   1 /******************************************************************************
   2  *
   3  * Module Name: nsparse - namespace interface to AML parser
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2004, 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
  45 #include <acpi/acpi.h>
  46 #include <acpi/acnamesp.h>
  47 #include <acpi/acparser.h>
  48 #include <acpi/acdispat.h>
  49
  50
  51 #define _COMPONENT          ACPI_NAMESPACE
  52          ACPI_MODULE_NAME    ("nsparse")
  53
  54
  55 /*******************************************************************************
  56  *
  57  * FUNCTION:    ns_one_complete_parse
  58  *
  59  * PARAMETERS:  pass_number             - 1 or 2
  60  *              table_desc              - The table to be parsed.
  61  *
  62  * RETURN:      Status
  63  *
  64  * DESCRIPTION: Perform one complete parse of an ACPI/AML table.
  65  *
  66  ******************************************************************************/
  67
  68 acpi_status
  69 acpi_ns_one_complete_parse (
  70         u32                             pass_number,
  71         struct acpi_table_desc          *table_desc)
  72 {
  73         union acpi_parse_object         *parse_root;
  74         acpi_status                     status;
  75         struct acpi_walk_state          *walk_state;
  76
  77
  78         ACPI_FUNCTION_TRACE ("ns_one_complete_parse");
  79
  80
  81         /* Create and init a Root Node */
  82
  83         parse_root = acpi_ps_create_scope_op ();
  84         if (!parse_root) {
  85                 return_ACPI_STATUS (AE_NO_MEMORY);
  86         }
  87
  88         /* Create and initialize a new walk state */
  89
  90         walk_state = acpi_ds_create_walk_state (table_desc->table_id,
  91                            NULL, NULL, NULL);
  92         if (!walk_state) {
  93                 acpi_ps_free_op (parse_root);
  94                 return_ACPI_STATUS (AE_NO_MEMORY);
  95         }
  96
  97         status = acpi_ds_init_aml_walk (walk_state, parse_root, NULL,
  98                           table_desc->aml_start, table_desc->aml_length,
  99                           NULL, pass_number);
 100         if (ACPI_FAILURE (status)) {
 101                 acpi_ds_delete_walk_state (walk_state);
 102                 return_ACPI_STATUS (status);
 103         }
 104
 105         /* Parse the AML */
 106
 107         ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "*PARSE* pass %d parse\n", pass_number));
 108         status = acpi_ps_parse_aml (walk_state);
 109
 110         acpi_ps_delete_parse_tree (parse_root);
 111         return_ACPI_STATUS (status);
 112 }
 113
 114
 115 /*******************************************************************************
 116  *
 117  * FUNCTION:    acpi_ns_parse_table
 118  *
 119  * PARAMETERS:  table_desc      - An ACPI table descriptor for table to parse
 120  *              start_node      - Where to enter the table into the namespace
 121  *
 122  * RETURN:      Status
 123  *
 124  * DESCRIPTION: Parse AML within an ACPI table and return a tree of ops
 125  *
 126  ******************************************************************************/
 127
 128 acpi_status
 129 acpi_ns_parse_table (
 130         struct acpi_table_desc          *table_desc,
 131         struct acpi_namespace_node      *start_node)
 132 {
 133         acpi_status                     status;
 134
 135
 136         ACPI_FUNCTION_TRACE ("ns_parse_table");
 137
 138
 139         /*
 140          * AML Parse, pass 1
 141          *
 142          * In this pass, we load most of the namespace.  Control methods
 143          * are not parsed until later.  A parse tree is not created.  Instead,
 144          * each Parser Op subtree is deleted when it is finished.  This saves
 145          * a great deal of memory, and allows a small cache of parse objects
 146          * to service the entire parse.  The second pass of the parse then
 147          * performs another complete parse of the AML..
 148          */
 149         status = acpi_ns_one_complete_parse (1, table_desc);
 150         if (ACPI_FAILURE (status)) {
 151                 return_ACPI_STATUS (status);
 152         }
 153
 154         /*
 155          * AML Parse, pass 2
 156          *
 157          * In this pass, we resolve forward references and other things
 158          * that could not be completed during the first pass.
 159          * Another complete parse of the AML is performed, but the
 160          * overhead of this is compensated for by the fact that the
 161          * parse objects are all cached.
 162          */
 163         status = acpi_ns_one_complete_parse (2, table_desc);
 164         if (ACPI_FAILURE (status)) {
 165                 return_ACPI_STATUS (status);
 166         }
 167
 168         return_ACPI_STATUS (status);
 169 }
 170
 171