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1 /******************************************************************************
3 * Module Name: tbutils - Table manipulation utilities
5 *****************************************************************************/
8 * Copyright (C) 2000 - 2006, R. Byron Moore
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
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.
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.
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.
44 #include <acpi/acpi.h>
45 #include <acpi/actables.h>
47 #define _COMPONENT ACPI_TABLES
48 ACPI_MODULE_NAME ( "tbutils" )
50 /* Local prototypes */
51 #ifdef ACPI_OBSOLETE_FUNCTIONS
53 acpi_tb_handle_to_object ( u16 table_id
, struct acpi_table_desc
** table_desc
);
56 /*******************************************************************************
58 * FUNCTION: acpi_tb_is_table_installed
60 * PARAMETERS: new_table_desc - Descriptor for new table being installed
62 * RETURN: Status - AE_ALREADY_EXISTS if the table is already installed
64 * DESCRIPTION: Determine if an ACPI table is already installed
66 * MUTEX: Table data structures should be locked
68 ******************************************************************************/
70 acpi_status
acpi_tb_is_table_installed ( struct acpi_table_desc
* new_table_desc
)
72 struct acpi_table_desc
* table_desc
;
74 ACPI_FUNCTION_TRACE ( "tb_is_table_installed" );
76 /* Get the list descriptor and first table descriptor */
78 table_desc
= acpi_gbl_table_lists
[ new_table_desc
-> type
]. next
;
80 /* Examine all installed tables of this type */
84 * If the table lengths match, perform a full bytewise compare. This
85 * means that we will allow tables with duplicate oem_table_id(s), as
86 * long as the tables are different in some way.
88 * Checking if the table has been loaded into the namespace means that
89 * we don't check for duplicate tables during the initial installation
90 * of tables within the RSDT/XSDT.
92 if (( table_desc
-> loaded_into_namespace
) &&
93 ( table_desc
-> pointer
-> length
==
94 new_table_desc
-> pointer
-> length
)
97 ( table_desc
-> pointer
, new_table_desc
-> pointer
,
98 new_table_desc
-> pointer
-> length
))) {
99 /* Match: this table is already installed */
101 ACPI_DEBUG_PRINT (( ACPI_DB_TABLES
,
102 "Table [%4.4s] already installed: Rev %X oem_table_id [%8.8s] \n " ,
103 new_table_desc
-> pointer
-> signature
,
104 new_table_desc
-> pointer
-> revision
,
105 new_table_desc
-> pointer
->
108 new_table_desc
-> owner_id
= table_desc
-> owner_id
;
109 new_table_desc
-> installed_desc
= table_desc
;
111 return_ACPI_STATUS ( AE_ALREADY_EXISTS
);
114 /* Get next table on the list */
116 table_desc
= table_desc
-> next
;
119 return_ACPI_STATUS ( AE_OK
);
122 /*******************************************************************************
124 * FUNCTION: acpi_tb_validate_table_header
126 * PARAMETERS: table_header - Logical pointer to the table
130 * DESCRIPTION: Check an ACPI table header for validity
132 * NOTE: Table pointers are validated as follows:
133 * 1) Table pointer must point to valid physical memory
134 * 2) Signature must be 4 ASCII chars, even if we don't recognize the
136 * 3) Table must be readable for length specified in the header
137 * 4) Table checksum must be valid (with the exception of the FACS
138 * which has no checksum because it contains variable fields)
140 ******************************************************************************/
143 acpi_tb_validate_table_header ( struct acpi_table_header
* table_header
)
147 ACPI_FUNCTION_ENTRY ();
149 /* Verify that this is a valid address */
151 if (! acpi_os_readable ( table_header
, sizeof ( struct acpi_table_header
))) {
152 ACPI_REPORT_ERROR (( "Cannot read table header at %p \n " ,
155 return ( AE_BAD_ADDRESS
);
158 /* Ensure that the signature is 4 ASCII characters */
160 ACPI_MOVE_32_TO_32 (& signature
, table_header
-> signature
);
161 if (! acpi_ut_valid_acpi_name ( signature
)) {
162 ACPI_REPORT_ERROR (( "Table signature at %p [%p] has invalid characters \n " , table_header
, & signature
));
164 ACPI_REPORT_WARNING (( "Invalid table signature found: [%4.4s] \n " ,
165 ACPI_CAST_PTR ( char , & signature
)));
167 ACPI_DUMP_BUFFER ( table_header
,
168 sizeof ( struct acpi_table_header
));
169 return ( AE_BAD_SIGNATURE
);
172 /* Validate the table length */
174 if ( table_header
-> length
< sizeof ( struct acpi_table_header
)) {
175 ACPI_REPORT_ERROR (( "Invalid length in table header %p name %4.4s \n " , table_header
, ( char *)& signature
));
177 ACPI_REPORT_WARNING (( "Invalid table header length (0x%X) found \n " , ( u32
) table_header
-> length
));
179 ACPI_DUMP_BUFFER ( table_header
,
180 sizeof ( struct acpi_table_header
));
181 return ( AE_BAD_HEADER
);
187 /*******************************************************************************
189 * FUNCTION: acpi_tb_verify_table_checksum
191 * PARAMETERS: *table_header - ACPI table to verify
193 * RETURN: 8 bit checksum of table
195 * DESCRIPTION: Does an 8 bit checksum of table and returns status. A correct
196 * table should have a checksum of 0.
198 ******************************************************************************/
201 acpi_tb_verify_table_checksum ( struct acpi_table_header
* table_header
)
204 acpi_status status
= AE_OK
;
206 ACPI_FUNCTION_TRACE ( "tb_verify_table_checksum" );
208 /* Compute the checksum on the table */
211 acpi_tb_generate_checksum ( table_header
, table_header
-> length
);
213 /* Return the appropriate exception */
216 ACPI_REPORT_WARNING (( "Invalid checksum in table [%4.4s] (%02X, sum %02X is not zero) \n " , table_header
-> signature
, ( u32
) table_header
-> checksum
, ( u32
) checksum
));
218 status
= AE_BAD_CHECKSUM
;
220 return_ACPI_STATUS ( status
);
223 /*******************************************************************************
225 * FUNCTION: acpi_tb_generate_checksum
227 * PARAMETERS: Buffer - Buffer to checksum
228 * Length - Size of the buffer
230 * RETURN: 8 bit checksum of buffer
232 * DESCRIPTION: Computes an 8 bit checksum of the buffer(length) and returns it.
234 ******************************************************************************/
236 u8
acpi_tb_generate_checksum ( void * buffer
, u32 length
)
242 if ( buffer
&& length
) {
243 /* Buffer and Length are valid */
245 end_buffer
= ACPI_ADD_PTR ( u8
, buffer
, length
);
247 for ( rover
= buffer
; rover
< end_buffer
; rover
++) {
248 sum
= ( u8
) ( sum
+ * rover
);
254 #ifdef ACPI_OBSOLETE_FUNCTIONS
255 /*******************************************************************************
257 * FUNCTION: acpi_tb_handle_to_object
259 * PARAMETERS: table_id - Id for which the function is searching
260 * table_desc - Pointer to return the matching table
263 * RETURN: Search the tables to find one with a matching table_id and
264 * return a pointer to that table descriptor.
266 ******************************************************************************/
269 acpi_tb_handle_to_object ( u16 table_id
,
270 struct acpi_table_desc
** return_table_desc
)
273 struct acpi_table_desc
* table_desc
;
275 ACPI_FUNCTION_NAME ( "tb_handle_to_object" );
277 for ( i
= 0 ; i
< ACPI_TABLE_MAX
; i
++) {
278 table_desc
= acpi_gbl_table_lists
[ i
]. next
;
280 if ( table_desc
-> table_id
== table_id
) {
281 * return_table_desc
= table_desc
;
285 table_desc
= table_desc
-> next
;
289 ACPI_REPORT_ERROR (( "table_id=%X does not exist \n " , table_id
));
290 return ( AE_BAD_PARAMETER
);