drivers/bus/acpi/acpica/parser/pswalk.c

   1 /******************************************************************************
   2  *
   3  * Module Name: pswalk - Parser routines to walk parsed op tree(s)
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2021, 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 MERCHANTABILITY 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.h"
  45 #include "accommon.h"
  46 #include "acparser.h"
  47
  48 #define _COMPONENT          ACPI_PARSER
  49         ACPI_MODULE_NAME    ("pswalk")
  50
  51
  52 /*******************************************************************************
  53  *
  54  * FUNCTION:    AcpiPsDeleteParseTree
  55  *
  56  * PARAMETERS:  SubtreeRoot         - Root of tree (or subtree) to delete
  57  *
  58  * RETURN:      None
  59  *
  60  * DESCRIPTION: Delete a portion of or an entire parse tree.
  61  *
  62  ******************************************************************************/
  63
  64 #include "amlcode.h"
  65
  66 void
  67 AcpiPsDeleteParseTree (
  68     ACPI_PARSE_OBJECT       *SubtreeRoot)
  69 {
  70     ACPI_PARSE_OBJECT       *Op = SubtreeRoot;
  71     ACPI_PARSE_OBJECT       *Next = NULL;
  72     ACPI_PARSE_OBJECT       *Parent = NULL;
  73     UINT32                  Level = 0;
  74
  75
  76     ACPI_FUNCTION_TRACE_PTR (PsDeleteParseTree, SubtreeRoot);
  77
  78     ACPI_DEBUG_PRINT ((ACPI_DB_PARSE_TREES,
  79         " root %p\n", SubtreeRoot));
  80
  81     /* Visit all nodes in the subtree */
  82
  83     while (Op)
  84     {
  85         if (Op != Parent)
  86         {
  87             /* This is the descending case */
  88
  89             if (ACPI_IS_DEBUG_ENABLED (ACPI_LV_PARSE_TREES, _COMPONENT))
  90             {
  91                 /* This debug option will print the entire parse tree */
  92
  93                 AcpiOsPrintf ("        %*.s%s %p", (Level * 4), " ",
  94                     AcpiPsGetOpcodeName (Op->Common.AmlOpcode), Op);
  95
  96                 if (Op->Named.AmlOpcode == AML_INT_NAMEPATH_OP)
  97                 {
  98                     AcpiOsPrintf ("    %4.4s", Op->Common.Value.String);
  99                 }
 100                 if (Op->Named.AmlOpcode == AML_STRING_OP)
 101                 {
 102                     AcpiOsPrintf ("    %s", Op->Common.Value.String);
 103                 }
 104                 AcpiOsPrintf ("\n");
 105             }
 106
 107             /* Look for an argument or child of the current op */
 108
 109             Next = AcpiPsGetArg (Op, 0);
 110             if (Next)
 111             {
 112                 /* Still going downward in tree (Op is not completed yet) */
 113
 114                 Op = Next;
 115                 Level++;
 116                 continue;
 117             }
 118         }
 119
 120         /* No more children, this Op is complete. */
 121
 122         Next = Op->Common.Next;
 123         Parent = Op->Common.Parent;
 124
 125         AcpiPsFreeOp (Op);
 126
 127         /* If we are back to the starting point, the walk is complete. */
 128
 129         if (Op == SubtreeRoot)
 130         {
 131             return_VOID;
 132         }
 133
 134         if (Next)
 135         {
 136             Op = Next;
 137         }
 138         else
 139         {
 140             Level--;
 141             Op = Parent;
 142         }
 143     }
 144
 145     return_VOID;
 146 }