tbutils.c revision 102550 
1/******************************************************************************
2 *
3 * Module Name: tbutils - Table manipulation utilities
4 *              $Revision: 56 $
5 *
6 *****************************************************************************/
7
8/******************************************************************************
9 *
10 * 1. Copyright Notice
11 *
12 * Some or all of this work - Copyright (c) 1999 - 2002, Intel Corp.
13 * All rights reserved.
14 *
15 * 2. License
16 *
17 * 2.1. This is your license from Intel Corp. under its intellectual property
18 * rights.  You may have additional license terms from the party that provided
19 * you this software, covering your right to use that party's intellectual
20 * property rights.
21 *
22 * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
23 * copy of the source code appearing in this file ("Covered Code") an
24 * irrevocable, perpetual, worldwide license under Intel's copyrights in the
25 * base code distributed originally by Intel ("Original Intel Code") to copy,
26 * make derivatives, distribute, use and display any portion of the Covered
27 * Code in any form, with the right to sublicense such rights; and
28 *
29 * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
30 * license (with the right to sublicense), under only those claims of Intel
31 * patents that are infringed by the Original Intel Code, to make, use, sell,
32 * offer to sell, and import the Covered Code and derivative works thereof
33 * solely to the minimum extent necessary to exercise the above copyright
34 * license, and in no event shall the patent license extend to any additions
35 * to or modifications of the Original Intel Code.  No other license or right
36 * is granted directly or by implication, estoppel or otherwise;
37 *
38 * The above copyright and patent license is granted only if the following
39 * conditions are met:
40 *
41 * 3. Conditions
42 *
43 * 3.1. Redistribution of Source with Rights to Further Distribute Source.
44 * Redistribution of source code of any substantial portion of the Covered
45 * Code or modification with rights to further distribute source must include
46 * the above Copyright Notice, the above License, this list of Conditions,
47 * and the following Disclaimer and Export Compliance provision.  In addition,
48 * Licensee must cause all Covered Code to which Licensee contributes to
49 * contain a file documenting the changes Licensee made to create that Covered
50 * Code and the date of any change.  Licensee must include in that file the
51 * documentation of any changes made by any predecessor Licensee.  Licensee
52 * must include a prominent statement that the modification is derived,
53 * directly or indirectly, from Original Intel Code.
54 *
55 * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
56 * Redistribution of source code of any substantial portion of the Covered
57 * Code or modification without rights to further distribute source must
58 * include the following Disclaimer and Export Compliance provision in the
59 * documentation and/or other materials provided with distribution.  In
60 * addition, Licensee may not authorize further sublicense of source of any
61 * portion of the Covered Code, and must include terms to the effect that the
62 * license from Licensee to its licensee is limited to the intellectual
63 * property embodied in the software Licensee provides to its licensee, and
64 * not to intellectual property embodied in modifications its licensee may
65 * make.
66 *
67 * 3.3. Redistribution of Executable. Redistribution in executable form of any
68 * substantial portion of the Covered Code or modification must reproduce the
69 * above Copyright Notice, and the following Disclaimer and Export Compliance
70 * provision in the documentation and/or other materials provided with the
71 * distribution.
72 *
73 * 3.4. Intel retains all right, title, and interest in and to the Original
74 * Intel Code.
75 *
76 * 3.5. Neither the name Intel nor any other trademark owned or controlled by
77 * Intel shall be used in advertising or otherwise to promote the sale, use or
78 * other dealings in products derived from or relating to the Covered Code
79 * without prior written authorization from Intel.
80 *
81 * 4. Disclaimer and Export Compliance
82 *
83 * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
84 * HERE.  ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
85 * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT,  ASSISTANCE,
86 * INSTALLATION, TRAINING OR OTHER SERVICES.  INTEL WILL NOT PROVIDE ANY
87 * UPDATES, ENHANCEMENTS OR EXTENSIONS.  INTEL SPECIFICALLY DISCLAIMS ANY
88 * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
89 * PARTICULAR PURPOSE.
90 *
91 * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
92 * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
93 * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
94 * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
95 * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
96 * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.  THESE LIMITATIONS
97 * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
98 * LIMITED REMEDY.
99 *
100 * 4.3. Licensee shall not export, either directly or indirectly, any of this
101 * software or system incorporating such software without first obtaining any
102 * required license or other approval from the U. S. Department of Commerce or
103 * any other agency or department of the United States Government.  In the
104 * event Licensee exports any such software from the United States or
105 * re-exports any such software from a foreign destination, Licensee shall
106 * ensure that the distribution and export/re-export of the software is in
107 * compliance with all laws, regulations, orders, or other restrictions of the
108 * U.S. Export Administration Regulations. Licensee agrees that neither it nor
109 * any of its subsidiaries will export/re-export any technical data, process,
110 * software, or service, directly or indirectly, to any country for which the
111 * United States government or any agency thereof requires an export license,
112 * other governmental approval, or letter of assurance, without first obtaining
113 * such license, approval or letter.
114 *
115 *****************************************************************************/
116
117#define __TBUTILS_C__
118
119#include "acpi.h"
120#include "actables.h"
121
122
123#define _COMPONENT          ACPI_TABLES
124        ACPI_MODULE_NAME    ("tbutils")
125
126
127/*******************************************************************************
128 *
129 * FUNCTION:    AcpiTbHandleToObject
130 *
131 * PARAMETERS:  TableId             - Id for which the function is searching
132 *              TableDesc           - Pointer to return the matching table
133 *                                      descriptor.
134 *
135 * RETURN:      Search the tables to find one with a matching TableId and
136 *              return a pointer to that table descriptor.
137 *
138 ******************************************************************************/
139
140ACPI_STATUS
141AcpiTbHandleToObject (
142    UINT16                  TableId,
143    ACPI_TABLE_DESC         **TableDesc)
144{
145    UINT32                  i;
146    ACPI_TABLE_DESC         *ListHead;
147
148
149    ACPI_FUNCTION_NAME ("TbHandleToObject");
150
151
152    for (i = 0; i < ACPI_TABLE_MAX; i++)
153    {
154        ListHead = &AcpiGbl_AcpiTables[i];
155        do
156        {
157            if (ListHead->TableId == TableId)
158            {
159                *TableDesc = ListHead;
160                return (AE_OK);
161            }
162
163            ListHead = ListHead->Next;
164
165        } while (ListHead != &AcpiGbl_AcpiTables[i]);
166    }
167
168    ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "TableId=%X does not exist\n", TableId));
169    return (AE_BAD_PARAMETER);
170}
171
172
173/*******************************************************************************
174 *
175 * FUNCTION:    AcpiTbValidateTableHeader
176 *
177 * PARAMETERS:  TableHeader         - Logical pointer to the table
178 *
179 * RETURN:      Status
180 *
181 * DESCRIPTION: Check an ACPI table header for validity
182 *
183 * NOTE:  Table pointers are validated as follows:
184 *          1) Table pointer must point to valid physical memory
185 *          2) Signature must be 4 ASCII chars, even if we don't recognize the
186 *             name
187 *          3) Table must be readable for length specified in the header
188 *          4) Table checksum must be valid (with the exception of the FACS
189 *              which has no checksum because it contains variable fields)
190 *
191 ******************************************************************************/
192
193ACPI_STATUS
194AcpiTbValidateTableHeader (
195    ACPI_TABLE_HEADER       *TableHeader)
196{
197    ACPI_NAME               Signature;
198
199
200    ACPI_FUNCTION_NAME ("TbValidateTableHeader");
201
202
203    /* Verify that this is a valid address */
204
205    if (!AcpiOsReadable (TableHeader, sizeof (ACPI_TABLE_HEADER)))
206    {
207        ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
208            "Cannot read table header at %p\n", TableHeader));
209        return (AE_BAD_ADDRESS);
210    }
211
212    /* Ensure that the signature is 4 ASCII characters */
213
214    ACPI_MOVE_UNALIGNED32_TO_32 (&Signature, TableHeader->Signature);
215    if (!AcpiUtValidAcpiName (Signature))
216    {
217        ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
218            "Table signature at %p [%p] has invalid characters\n",
219            TableHeader, &Signature));
220
221        ACPI_REPORT_WARNING (("Invalid table signature found: [%4.4s]\n",
222            (char *) &Signature));
223        ACPI_DUMP_BUFFER (TableHeader, sizeof (ACPI_TABLE_HEADER));
224        return (AE_BAD_SIGNATURE);
225    }
226
227    /* Validate the table length */
228
229    if (TableHeader->Length < sizeof (ACPI_TABLE_HEADER))
230    {
231        ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
232            "Invalid length in table header %p name %4.4s\n",
233            TableHeader, (char *) &Signature));
234
235        ACPI_REPORT_WARNING (("Invalid table header length (0x%X) found\n",
236            (UINT32) TableHeader->Length));
237        ACPI_DUMP_BUFFER (TableHeader, sizeof (ACPI_TABLE_HEADER));
238        return (AE_BAD_HEADER);
239    }
240
241    return (AE_OK);
242}
243
244
245/*******************************************************************************
246 *
247 * FUNCTION:    AcpiTbVerifyTableChecksum
248 *
249 * PARAMETERS:  *TableHeader            - ACPI table to verify
250 *
251 * RETURN:      8 bit checksum of table
252 *
253 * DESCRIPTION: Does an 8 bit checksum of table and returns status.  A correct
254 *              table should have a checksum of 0.
255 *
256 ******************************************************************************/
257
258ACPI_STATUS
259AcpiTbVerifyTableChecksum (
260    ACPI_TABLE_HEADER       *TableHeader)
261{
262    UINT8                   Checksum;
263    ACPI_STATUS             Status = AE_OK;
264
265
266    ACPI_FUNCTION_TRACE ("TbVerifyTableChecksum");
267
268
269    /* Compute the checksum on the table */
270
271    Checksum = AcpiTbChecksum (TableHeader, TableHeader->Length);
272
273    /* Return the appropriate exception */
274
275    if (Checksum)
276    {
277        ACPI_REPORT_WARNING (("Invalid checksum (%X) in table %4.4s\n",
278            (UINT32) Checksum, TableHeader->Signature));
279
280        Status = AE_BAD_CHECKSUM;
281    }
282    return_ACPI_STATUS (Status);
283}
284
285
286/*******************************************************************************
287 *
288 * FUNCTION:    AcpiTbChecksum
289 *
290 * PARAMETERS:  Buffer              - Buffer to checksum
291 *              Length              - Size of the buffer
292 *
293 * RETURNS      8 bit checksum of buffer
294 *
295 * DESCRIPTION: Computes an 8 bit checksum of the buffer(length) and returns it.
296 *
297 ******************************************************************************/
298
299UINT8
300AcpiTbChecksum (
301    void                    *Buffer,
302    UINT32                  Length)
303{
304    const UINT8             *limit;
305    const UINT8             *rover;
306    UINT8                   sum = 0;
307
308
309    if (Buffer && Length)
310    {
311        /*  Buffer and Length are valid   */
312
313        limit = (UINT8 *) Buffer + Length;
314
315        for (rover = Buffer; rover < limit; rover++)
316        {
317            sum = (UINT8) (sum + *rover);
318        }
319    }
320    return (sum);
321}
322
323
324