release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/acpi/acpica/exutils.c

   1
   2 /******************************************************************************
   3  *
   4  * Module Name: exutils - interpreter/scanner utilities
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2010, Intel Corp.
  10  * All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions, and the following disclaimer,
  17  *    without modification.
  18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  19  *    substantially similar to the "NO WARRANTY" disclaimer below
  20  *    ("Disclaimer") and any redistribution must be conditioned upon
  21  *    including a substantially similar Disclaimer requirement for further
  22  *    binary redistribution.
  23  * 3. Neither the names of the above-listed copyright holders nor the names
  24  *    of any contributors may be used to endorse or promote products derived
  25  *    from this software without specific prior written permission.
  26  *
  27  * Alternatively, this software may be distributed under the terms of the
  28  * GNU General Public License ("GPL") version 2 as published by the Free
  29  * Software Foundation.
  30  *
  31  * NO WARRANTY
  32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  42  * POSSIBILITY OF SUCH DAMAGES.
  43  */
  44
  45 /*
  46  * DEFINE_AML_GLOBALS is tested in amlcode.h
  47  * to determine whether certain global names should be "defined" or only
  48  * "declared" in the current compilation.  This enhances maintainability
  49  * by enabling a single header file to embody all knowledge of the names
  50  * in question.
  51  *
  52  * Exactly one module of any executable should #define DEFINE_GLOBALS
  53  * before #including the header files which use this convention.  The
  54  * names in question will be defined and initialized in that module,
  55  * and declared as extern in all other modules which #include those
  56  * header files.
  57  */
  58
  59 #define DEFINE_AML_GLOBALS
  60
  61 #include <acpi/acpi.h>
  62 #include "accommon.h"
  63 #include "acinterp.h"
  64 #include "amlcode.h"
  65
  66 #define _COMPONENT          ACPI_EXECUTER
  67 ACPI_MODULE_NAME("exutils")
  68
  69 /* Local prototypes */
  70 static u32 acpi_ex_digits_needed(u64 value, u32 base);
  71
  72 #ifndef ACPI_NO_METHOD_EXECUTION
  73 /*******************************************************************************
  74  *
  75  * FUNCTION:    acpi_ex_enter_interpreter
  76  *
  77  * PARAMETERS:  None
  78  *
  79  * RETURN:      None
  80  *
  81  * DESCRIPTION: Enter the interpreter execution region. Failure to enter
  82  *              the interpreter region is a fatal system error. Used in
  83  *              conjunction with exit_interpreter.
  84  *
  85  ******************************************************************************/
  86
  87 void acpi_ex_enter_interpreter(void)
  88 {
  89         acpi_status status;
  90
  91         ACPI_FUNCTION_TRACE(ex_enter_interpreter);
  92
  93         status = acpi_ut_acquire_mutex(ACPI_MTX_INTERPRETER);
  94         if (ACPI_FAILURE(status)) {
  95                 ACPI_ERROR((AE_INFO,
  96                             "Could not acquire AML Interpreter mutex"));
  97         }
  98
  99         return_VOID;
 100 }
 101
 102 /*******************************************************************************
 103  *
 104  * FUNCTION:    acpi_ex_reacquire_interpreter
 105  *
 106  * PARAMETERS:  None
 107  *
 108  * RETURN:      None
 109  *
 110  * DESCRIPTION: Reacquire the interpreter execution region from within the
 111  *              interpreter code. Failure to enter the interpreter region is a
 112  *              fatal system error. Used in  conjunction with
 113  *              relinquish_interpreter
 114  *
 115  ******************************************************************************/
 116
 117 void acpi_ex_reacquire_interpreter(void)
 118 {
 119         ACPI_FUNCTION_TRACE(ex_reacquire_interpreter);
 120
 121         /*
 122          * If the global serialized flag is set, do not release the interpreter,
 123          * since it was not actually released by acpi_ex_relinquish_interpreter.
 124          * This forces the interpreter to be single threaded.
 125          */
 126         if (!acpi_gbl_all_methods_serialized) {
 127                 acpi_ex_enter_interpreter();
 128         }
 129
 130         return_VOID;
 131 }
 132
 133 /*******************************************************************************
 134  *
 135  * FUNCTION:    acpi_ex_exit_interpreter
 136  *
 137  * PARAMETERS:  None
 138  *
 139  * RETURN:      None
 140  *
 141  * DESCRIPTION: Exit the interpreter execution region. This is the top level
 142  *              routine used to exit the interpreter when all processing has
 143  *              been completed.
 144  *
 145  ******************************************************************************/
 146
 147 void acpi_ex_exit_interpreter(void)
 148 {
 149         acpi_status status;
 150
 151         ACPI_FUNCTION_TRACE(ex_exit_interpreter);
 152
 153         status = acpi_ut_release_mutex(ACPI_MTX_INTERPRETER);
 154         if (ACPI_FAILURE(status)) {
 155                 ACPI_ERROR((AE_INFO,
 156                             "Could not release AML Interpreter mutex"));
 157         }
 158
 159         return_VOID;
 160 }
 161
 162 /*******************************************************************************
 163  *
 164  * FUNCTION:    acpi_ex_relinquish_interpreter
 165  *
 166  * PARAMETERS:  None
 167  *
 168  * RETURN:      None
 169  *
 170  * DESCRIPTION: Exit the interpreter execution region, from within the
 171  *              interpreter - before attempting an operation that will possibly
 172  *              block the running thread.
 173  *
 174  * Cases where the interpreter is unlocked internally
 175  *      1) Method to be blocked on a Sleep() AML opcode
 176  *      2) Method to be blocked on an Acquire() AML opcode
 177  *      3) Method to be blocked on a Wait() AML opcode
 178  *      4) Method to be blocked to acquire the global lock
 179  *      5) Method to be blocked waiting to execute a serialized control method
 180  *          that is currently executing
 181  *      6) About to invoke a user-installed opregion handler
 182  *
 183  ******************************************************************************/
 184
 185 void acpi_ex_relinquish_interpreter(void)
 186 {
 187         ACPI_FUNCTION_TRACE(ex_relinquish_interpreter);
 188
 189         /*
 190          * If the global serialized flag is set, do not release the interpreter.
 191          * This forces the interpreter to be single threaded.
 192          */
 193         if (!acpi_gbl_all_methods_serialized) {
 194                 acpi_ex_exit_interpreter();
 195         }
 196
 197         return_VOID;
 198 }
 199
 200 /*******************************************************************************
 201  *
 202  * FUNCTION:    acpi_ex_truncate_for32bit_table
 203  *
 204  * PARAMETERS:  obj_desc        - Object to be truncated
 205  *
 206  * RETURN:      none
 207  *
 208  * DESCRIPTION: Truncate an ACPI Integer to 32 bits if the execution mode is
 209  *              32-bit, as determined by the revision of the DSDT.
 210  *
 211  ******************************************************************************/
 212
 213 void acpi_ex_truncate_for32bit_table(union acpi_operand_object *obj_desc)
 214 {
 215
 216         ACPI_FUNCTION_ENTRY();
 217
 218         /*
 219          * Object must be a valid number and we must be executing
 220          * a control method. NS node could be there for AML_INT_NAMEPATH_OP.
 221          */
 222         if ((!obj_desc) ||
 223             (ACPI_GET_DESCRIPTOR_TYPE(obj_desc) != ACPI_DESC_TYPE_OPERAND) ||
 224             (obj_desc->common.type != ACPI_TYPE_INTEGER)) {
 225                 return;
 226         }
 227
 228         if (acpi_gbl_integer_byte_width == 4) {
 229                 /*
 230                  * We are running a method that exists in a 32-bit ACPI table.
 231                  * Truncate the value to 32 bits by zeroing out the upper 32-bit field
 232                  */
 233                 obj_desc->integer.value &= (u64) ACPI_UINT32_MAX;
 234         }
 235 }
 236
 237 /*******************************************************************************
 238  *
 239  * FUNCTION:    acpi_ex_acquire_global_lock
 240  *
 241  * PARAMETERS:  field_flags           - Flags with Lock rule:
 242  *                                      always_lock or never_lock
 243  *
 244  * RETURN:      None
 245  *
 246  * DESCRIPTION: Obtain the ACPI hardware Global Lock, only if the field
 247  *              flags specifiy that it is to be obtained before field access.
 248  *
 249  ******************************************************************************/
 250
 251 void acpi_ex_acquire_global_lock(u32 field_flags)
 252 {
 253         acpi_status status;
 254
 255         ACPI_FUNCTION_TRACE(ex_acquire_global_lock);
 256
 257         /* Only use the lock if the always_lock bit is set */
 258
 259         if (!(field_flags & AML_FIELD_LOCK_RULE_MASK)) {
 260                 return_VOID;
 261         }
 262
 263         /* Attempt to get the global lock, wait forever */
 264
 265         status = acpi_ex_acquire_mutex_object(ACPI_WAIT_FOREVER,
 266                                               acpi_gbl_global_lock_mutex,
 267                                               acpi_os_get_thread_id());
 268
 269         if (ACPI_FAILURE(status)) {
 270                 ACPI_EXCEPTION((AE_INFO, status,
 271                                 "Could not acquire Global Lock"));
 272         }
 273
 274         return_VOID;
 275 }
 276
 277 /*******************************************************************************
 278  *
 279  * FUNCTION:    acpi_ex_release_global_lock
 280  *
 281  * PARAMETERS:  field_flags           - Flags with Lock rule:
 282  *                                      always_lock or never_lock
 283  *
 284  * RETURN:      None
 285  *
 286  * DESCRIPTION: Release the ACPI hardware Global Lock
 287  *
 288  ******************************************************************************/
 289
 290 void acpi_ex_release_global_lock(u32 field_flags)
 291 {
 292         acpi_status status;
 293
 294         ACPI_FUNCTION_TRACE(ex_release_global_lock);
 295
 296         /* Only use the lock if the always_lock bit is set */
 297
 298         if (!(field_flags & AML_FIELD_LOCK_RULE_MASK)) {
 299                 return_VOID;
 300         }
 301
 302         /* Release the global lock */
 303
 304         status = acpi_ex_release_mutex_object(acpi_gbl_global_lock_mutex);
 305         if (ACPI_FAILURE(status)) {
 306
 307                 /* Report the error, but there isn't much else we can do */
 308
 309                 ACPI_EXCEPTION((AE_INFO, status,
 310                                 "Could not release Global Lock"));
 311         }
 312
 313         return_VOID;
 314 }
 315
 316 /*******************************************************************************
 317  *
 318  * FUNCTION:    acpi_ex_digits_needed
 319  *
 320  * PARAMETERS:  Value           - Value to be represented
 321  *              Base            - Base of representation
 322  *
 323  * RETURN:      The number of digits.
 324  *
 325  * DESCRIPTION: Calculate the number of digits needed to represent the Value
 326  *              in the given Base (Radix)
 327  *
 328  ******************************************************************************/
 329
 330 static u32 acpi_ex_digits_needed(u64 value, u32 base)
 331 {
 332         u32 num_digits;
 333         u64 current_value;
 334
 335         ACPI_FUNCTION_TRACE(ex_digits_needed);
 336
 337         /* u64 is unsigned, so we don't worry about a '-' prefix */
 338
 339         if (value == 0) {
 340                 return_UINT32(1);
 341         }
 342
 343         current_value = value;
 344         num_digits = 0;
 345
 346         /* Count the digits in the requested base */
 347
 348         while (current_value) {
 349                 (void)acpi_ut_short_divide(current_value, base, &current_value,
 350                                            NULL);
 351                 num_digits++;
 352         }
 353
 354         return_UINT32(num_digits);
 355 }
 356
 357 /*******************************************************************************
 358  *
 359  * FUNCTION:    acpi_ex_eisa_id_to_string
 360  *
 361  * PARAMETERS:  compressed_id   - EISAID to be converted
 362  *              out_string      - Where to put the converted string (8 bytes)
 363  *
 364  * RETURN:      None
 365  *
 366  * DESCRIPTION: Convert a numeric EISAID to string representation. Return
 367  *              buffer must be large enough to hold the string. The string
 368  *              returned is always exactly of length ACPI_EISAID_STRING_SIZE
 369  *              (includes null terminator). The EISAID is always 32 bits.
 370  *
 371  ******************************************************************************/
 372
 373 void acpi_ex_eisa_id_to_string(char *out_string, u64 compressed_id)
 374 {
 375         u32 swapped_id;
 376
 377         ACPI_FUNCTION_ENTRY();
 378
 379         /* The EISAID should be a 32-bit integer */
 380
 381         if (compressed_id > ACPI_UINT32_MAX) {
 382                 ACPI_WARNING((AE_INFO,
 383                               "Expected EISAID is larger than 32 bits: 0x%8.8X%8.8X, truncating",
 384                               ACPI_FORMAT_UINT64(compressed_id)));
 385         }
 386
 387         /* Swap ID to big-endian to get contiguous bits */
 388
 389         swapped_id = acpi_ut_dword_byte_swap((u32)compressed_id);
 390
 391         /* First 3 bytes are uppercase letters. Next 4 bytes are hexadecimal */
 392
 393         out_string[0] =
 394             (char)(0x40 + (((unsigned long)swapped_id >> 26) & 0x1F));
 395         out_string[1] = (char)(0x40 + ((swapped_id >> 21) & 0x1F));
 396         out_string[2] = (char)(0x40 + ((swapped_id >> 16) & 0x1F));
 397         out_string[3] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 12);
 398         out_string[4] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 8);
 399         out_string[5] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 4);
 400         out_string[6] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 0);
 401         out_string[7] = 0;
 402 }
 403
 404 /*******************************************************************************
 405  *
 406  * FUNCTION:    acpi_ex_integer_to_string
 407  *
 408  * PARAMETERS:  out_string      - Where to put the converted string. At least
 409  *                                21 bytes are needed to hold the largest
 410  *                                possible 64-bit integer.
 411  *              Value           - Value to be converted
 412  *
 413  * RETURN:      None, string
 414  *
 415  * DESCRIPTION: Convert a 64-bit integer to decimal string representation.
 416  *              Assumes string buffer is large enough to hold the string. The
 417  *              largest string is (ACPI_MAX64_DECIMAL_DIGITS + 1).
 418  *
 419  ******************************************************************************/
 420
 421 void acpi_ex_integer_to_string(char *out_string, u64 value)
 422 {
 423         u32 count;
 424         u32 digits_needed;
 425         u32 remainder;
 426
 427         ACPI_FUNCTION_ENTRY();
 428
 429         digits_needed = acpi_ex_digits_needed(value, 10);
 430         out_string[digits_needed] = 0;
 431
 432         for (count = digits_needed; count > 0; count--) {
 433                 (void)acpi_ut_short_divide(value, 10, &value, &remainder);
 434                 out_string[count - 1] = (char)('0' + remainder);
 435         }
 436 }
 437
 438 #endif