drivers/acpi/tables/tbrsdt.c

   1 /******************************************************************************
   2  *
   3  * Module Name: tbrsdt - ACPI RSDT table utilities
   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/actables.h>
  46
  47 #define _COMPONENT          ACPI_TABLES
  48 ACPI_MODULE_NAME("tbrsdt")
  49
  50 /*******************************************************************************
  51  *
  52  * FUNCTION:    acpi_tb_verify_rsdp
  53  *
  54  * PARAMETERS:  Address         - RSDP (Pointer to RSDT)
  55  *
  56  * RETURN:      Status
  57  *
  58  * DESCRIPTION: Load and validate the RSDP (ptr) and RSDT (table)
  59  *
  60  ******************************************************************************/
  61 acpi_status acpi_tb_verify_rsdp(struct acpi_pointer *address)
  62 {
  63         struct acpi_table_desc table_info;
  64         acpi_status status;
  65         struct rsdp_descriptor *rsdp;
  66
  67         ACPI_FUNCTION_TRACE(tb_verify_rsdp);
  68
  69         switch (address->pointer_type) {
  70         case ACPI_LOGICAL_POINTER:
  71
  72                 rsdp = address->pointer.logical;
  73                 break;
  74
  75         case ACPI_PHYSICAL_POINTER:
  76                 /*
  77                  * Obtain access to the RSDP structure
  78                  */
  79                 status = acpi_os_map_memory(address->pointer.physical,
  80                                             sizeof(struct rsdp_descriptor),
  81                                             ACPI_CAST_PTR(void, &rsdp));
  82                 if (ACPI_FAILURE(status)) {
  83                         return_ACPI_STATUS(status);
  84                 }
  85                 break;
  86
  87         default:
  88                 return_ACPI_STATUS(AE_BAD_PARAMETER);
  89         }
  90
  91         /* Verify RSDP signature and checksum */
  92
  93         status = acpi_tb_validate_rsdp(rsdp);
  94         if (ACPI_FAILURE(status)) {
  95                 goto cleanup;
  96         }
  97
  98         /* RSDP is ok. Init the table info */
  99
 100         table_info.pointer = ACPI_CAST_PTR(struct acpi_table_header, rsdp);
 101         table_info.length = sizeof(struct rsdp_descriptor);
 102
 103         if (address->pointer_type == ACPI_PHYSICAL_POINTER) {
 104                 table_info.allocation = ACPI_MEM_MAPPED;
 105         } else {
 106                 table_info.allocation = ACPI_MEM_NOT_ALLOCATED;
 107         }
 108
 109         /* Save the table pointers and allocation info */
 110
 111         status = acpi_tb_init_table_descriptor(ACPI_TABLE_ID_RSDP, &table_info);
 112         if (ACPI_FAILURE(status)) {
 113                 goto cleanup;
 114         }
 115
 116         /* Save the RSDP in a global for easy access */
 117
 118         acpi_gbl_RSDP =
 119             ACPI_CAST_PTR(struct rsdp_descriptor, table_info.pointer);
 120         return_ACPI_STATUS(status);
 121
 122         /* Error exit */
 123       cleanup:
 124
 125         if (acpi_gbl_table_flags & ACPI_PHYSICAL_POINTER) {
 126                 acpi_os_unmap_memory(rsdp, sizeof(struct rsdp_descriptor));
 127         }
 128         return_ACPI_STATUS(status);
 129 }
 130
 131 /*******************************************************************************
 132  *
 133  * FUNCTION:    acpi_tb_get_rsdt_address
 134  *
 135  * PARAMETERS:  out_address         - Where the address is returned
 136  *
 137  * RETURN:      None, Address
 138  *
 139  * DESCRIPTION: Extract the address of either the RSDT or XSDT, depending on the
 140  *              version of the RSDP and whether the XSDT pointer is valid
 141  *
 142  ******************************************************************************/
 143
 144 void acpi_tb_get_rsdt_address(struct acpi_pointer *out_address)
 145 {
 146
 147         ACPI_FUNCTION_ENTRY();
 148
 149         out_address->pointer_type =
 150             acpi_gbl_table_flags | ACPI_LOGICAL_ADDRESSING;
 151
 152         /* Use XSDT if it is present */
 153
 154         if ((acpi_gbl_RSDP->revision >= 2) &&
 155             acpi_gbl_RSDP->xsdt_physical_address) {
 156                 out_address->pointer.value =
 157                     acpi_gbl_RSDP->xsdt_physical_address;
 158                 acpi_gbl_root_table_type = ACPI_TABLE_TYPE_XSDT;
 159         } else {
 160                 /* No XSDT, use the RSDT */
 161
 162                 out_address->pointer.value =
 163                     acpi_gbl_RSDP->rsdt_physical_address;
 164                 acpi_gbl_root_table_type = ACPI_TABLE_TYPE_RSDT;
 165         }
 166 }
 167
 168 /*******************************************************************************
 169  *
 170  * FUNCTION:    acpi_tb_validate_rsdt
 171  *
 172  * PARAMETERS:  table_ptr       - Addressable pointer to the RSDT.
 173  *
 174  * RETURN:      Status
 175  *
 176  * DESCRIPTION: Validate signature for the RSDT or XSDT
 177  *
 178  ******************************************************************************/
 179
 180 acpi_status acpi_tb_validate_rsdt(struct acpi_table_header *table_ptr)
 181 {
 182         char *signature;
 183
 184         ACPI_FUNCTION_ENTRY();
 185
 186         /* Validate minimum length */
 187
 188         if (table_ptr->length < sizeof(struct acpi_table_header)) {
 189                 ACPI_ERROR((AE_INFO,
 190                             "RSDT/XSDT length (%X) is smaller than minimum (%X)",
 191                             table_ptr->length,
 192                             sizeof(struct acpi_table_header)));
 193
 194                 return (AE_INVALID_TABLE_LENGTH);
 195         }
 196
 197         /* Search for appropriate signature, RSDT or XSDT */
 198
 199         if (acpi_gbl_root_table_type == ACPI_TABLE_TYPE_RSDT) {
 200                 signature = RSDT_SIG;
 201         } else {
 202                 signature = XSDT_SIG;
 203         }
 204
 205         if (!ACPI_COMPARE_NAME(table_ptr->signature, signature)) {
 206
 207                 /* Invalid RSDT or XSDT signature */
 208
 209                 ACPI_ERROR((AE_INFO,
 210                             "Invalid signature where RSDP indicates RSDT/XSDT should be located. RSDP:"));
 211
 212                 ACPI_DUMP_BUFFER(acpi_gbl_RSDP, 20);
 213
 214                 ACPI_ERROR((AE_INFO,
 215                             "RSDT/XSDT signature at %X is invalid",
 216                             acpi_gbl_RSDP->rsdt_physical_address));
 217
 218                 if (acpi_gbl_root_table_type == ACPI_TABLE_TYPE_RSDT) {
 219                         ACPI_ERROR((AE_INFO, "Looking for RSDT"));
 220                 } else {
 221                         ACPI_ERROR((AE_INFO, "Looking for XSDT"));
 222                 }
 223
 224                 ACPI_DUMP_BUFFER(ACPI_CAST_PTR(char, table_ptr), 48);
 225                 return (AE_BAD_SIGNATURE);
 226         }
 227
 228         return (AE_OK);
 229 }
 230
 231 /*******************************************************************************
 232  *
 233  * FUNCTION:    acpi_tb_get_table_rsdt
 234  *
 235  * PARAMETERS:  None
 236  *
 237  * RETURN:      Status
 238  *
 239  * DESCRIPTION: Load and validate the RSDP (ptr) and RSDT (table)
 240  *
 241  ******************************************************************************/
 242
 243 acpi_status acpi_tb_get_table_rsdt(void)
 244 {
 245         struct acpi_table_desc table_info;
 246         acpi_status status;
 247         struct acpi_pointer address;
 248
 249         ACPI_FUNCTION_TRACE(tb_get_table_rsdt);
 250
 251         /* Get the RSDT/XSDT via the RSDP */
 252
 253         acpi_tb_get_rsdt_address(&address);
 254
 255         table_info.type = ACPI_TABLE_ID_XSDT;
 256         status = acpi_tb_get_table(&address, &table_info);
 257         if (ACPI_FAILURE(status)) {
 258                 ACPI_EXCEPTION((AE_INFO, status,
 259                                 "Could not get the RSDT/XSDT"));
 260                 return_ACPI_STATUS(status);
 261         }
 262
 263         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 264                           "RSDP located at %p, points to RSDT physical=%8.8X%8.8X\n",
 265                           acpi_gbl_RSDP,
 266                           ACPI_FORMAT_UINT64(address.pointer.value)));
 267
 268         /* Check the RSDT or XSDT signature */
 269
 270         status = acpi_tb_validate_rsdt(table_info.pointer);
 271         if (ACPI_FAILURE(status)) {
 272                 goto error_cleanup;
 273         }
 274
 275         /* Get the number of tables defined in the RSDT or XSDT */
 276
 277         acpi_gbl_rsdt_table_count = acpi_tb_get_table_count(acpi_gbl_RSDP,
 278                                                             table_info.pointer);
 279
 280         /* Convert and/or copy to an XSDT structure */
 281
 282         status = acpi_tb_convert_to_xsdt(&table_info);
 283         if (ACPI_FAILURE(status)) {
 284                 goto error_cleanup;
 285         }
 286
 287         /* Save the table pointers and allocation info */
 288
 289         status = acpi_tb_init_table_descriptor(ACPI_TABLE_ID_XSDT, &table_info);
 290         if (ACPI_FAILURE(status)) {
 291                 goto error_cleanup;
 292         }
 293
 294         acpi_gbl_XSDT =
 295             ACPI_CAST_PTR(struct xsdt_descriptor, table_info.pointer);
 296
 297         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "XSDT located at %p\n", acpi_gbl_XSDT));
 298         return_ACPI_STATUS(status);
 299
 300       error_cleanup:
 301
 302         /* Free table allocated by acpi_tb_get_table */
 303
 304         acpi_tb_delete_single_table(&table_info);
 305
 306         return_ACPI_STATUS(status);
 307 }