drivers/acpi/executer/exutils.c

   1
   2 /******************************************************************************
   3  *
   4  * Module Name: exutils - interpreter/scanner utilities
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2006, R. Byron Moore
  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 <acpi/acinterp.h>
  63 #include <acpi/amlcode.h>
  64 #include <acpi/acevents.h>
  65
  66 #define _COMPONENT          ACPI_EXECUTER
  67 ACPI_MODULE_NAME("exutils")
  68
  69 /* Local prototypes */
  70 static u32 acpi_ex_digits_needed(acpi_integer 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:      Status
  80  *
  81  * DESCRIPTION: Enter the interpreter execution region.  Failure to enter
  82  *              the interpreter region is a fatal system error
  83  *
  84  ******************************************************************************/
  85
  86 acpi_status acpi_ex_enter_interpreter(void)
  87 {
  88         acpi_status status;
  89
  90         ACPI_FUNCTION_TRACE("ex_enter_interpreter");
  91
  92         status = acpi_ut_acquire_mutex(ACPI_MTX_EXECUTE);
  93         if (ACPI_FAILURE(status)) {
  94                 ACPI_ERROR((AE_INFO, "Could not acquire interpreter mutex"));
  95         }
  96
  97         return_ACPI_STATUS(status);
  98 }
  99
 100 /*******************************************************************************
 101  *
 102  * FUNCTION:    acpi_ex_exit_interpreter
 103  *
 104  * PARAMETERS:  None
 105  *
 106  * RETURN:      None
 107  *
 108  * DESCRIPTION: Exit the interpreter execution region
 109  *
 110  * Cases where the interpreter is unlocked:
 111  *      1) Completion of the execution of a control method
 112  *      2) Method blocked on a Sleep() AML opcode
 113  *      3) Method blocked on an Acquire() AML opcode
 114  *      4) Method blocked on a Wait() AML opcode
 115  *      5) Method blocked to acquire the global lock
 116  *      6) Method blocked to execute a serialized control method that is
 117  *          already executing
 118  *      7) About to invoke a user-installed opregion handler
 119  *
 120  ******************************************************************************/
 121
 122 void acpi_ex_exit_interpreter(void)
 123 {
 124         acpi_status status;
 125
 126         ACPI_FUNCTION_TRACE("ex_exit_interpreter");
 127
 128         status = acpi_ut_release_mutex(ACPI_MTX_EXECUTE);
 129         if (ACPI_FAILURE(status)) {
 130                 ACPI_ERROR((AE_INFO, "Could not release interpreter mutex"));
 131         }
 132
 133         return_VOID;
 134 }
 135
 136 /*******************************************************************************
 137  *
 138  * FUNCTION:    acpi_ex_truncate_for32bit_table
 139  *
 140  * PARAMETERS:  obj_desc        - Object to be truncated
 141  *
 142  * RETURN:      none
 143  *
 144  * DESCRIPTION: Truncate a number to 32-bits if the currently executing method
 145  *              belongs to a 32-bit ACPI table.
 146  *
 147  ******************************************************************************/
 148
 149 void acpi_ex_truncate_for32bit_table(union acpi_operand_object *obj_desc)
 150 {
 151
 152         ACPI_FUNCTION_ENTRY();
 153
 154         /*
 155          * Object must be a valid number and we must be executing
 156          * a control method
 157          */
 158         if ((!obj_desc) ||
 159             (ACPI_GET_OBJECT_TYPE(obj_desc) != ACPI_TYPE_INTEGER)) {
 160                 return;
 161         }
 162
 163         if (acpi_gbl_integer_byte_width == 4) {
 164                 /*
 165                  * We are running a method that exists in a 32-bit ACPI table.
 166                  * Truncate the value to 32 bits by zeroing out the upper 32-bit field
 167                  */
 168                 obj_desc->integer.value &= (acpi_integer) ACPI_UINT32_MAX;
 169         }
 170 }
 171
 172 /*******************************************************************************
 173  *
 174  * FUNCTION:    acpi_ex_acquire_global_lock
 175  *
 176  * PARAMETERS:  field_flags           - Flags with Lock rule:
 177  *                                      always_lock or never_lock
 178  *
 179  * RETURN:      TRUE/FALSE indicating whether the lock was actually acquired
 180  *
 181  * DESCRIPTION: Obtain the global lock and keep track of this fact via two
 182  *              methods.  A global variable keeps the state of the lock, and
 183  *              the state is returned to the caller.
 184  *
 185  ******************************************************************************/
 186
 187 u8 acpi_ex_acquire_global_lock(u32 field_flags)
 188 {
 189         u8 locked = FALSE;
 190         acpi_status status;
 191
 192         ACPI_FUNCTION_TRACE("ex_acquire_global_lock");
 193
 194         /* Only attempt lock if the always_lock bit is set */
 195
 196         if (field_flags & AML_FIELD_LOCK_RULE_MASK) {
 197                 /* We should attempt to get the lock, wait forever */
 198
 199                 status = acpi_ev_acquire_global_lock(ACPI_WAIT_FOREVER);
 200                 if (ACPI_SUCCESS(status)) {
 201                         locked = TRUE;
 202                 } else {
 203                         ACPI_EXCEPTION((AE_INFO, status,
 204                                         "Could not acquire Global Lock"));
 205                 }
 206         }
 207
 208         return_UINT8(locked);
 209 }
 210
 211 /*******************************************************************************
 212  *
 213  * FUNCTION:    acpi_ex_release_global_lock
 214  *
 215  * PARAMETERS:  locked_by_me    - Return value from corresponding call to
 216  *                                acquire_global_lock.
 217  *
 218  * RETURN:      None
 219  *
 220  * DESCRIPTION: Release the global lock if it is locked.
 221  *
 222  ******************************************************************************/
 223
 224 void acpi_ex_release_global_lock(u8 locked_by_me)
 225 {
 226         acpi_status status;
 227
 228         ACPI_FUNCTION_TRACE("ex_release_global_lock");
 229
 230         /* Only attempt unlock if the caller locked it */
 231
 232         if (locked_by_me) {
 233                 /* OK, now release the lock */
 234
 235                 status = acpi_ev_release_global_lock();
 236                 if (ACPI_FAILURE(status)) {
 237                         /* Report the error, but there isn't much else we can do */
 238
 239                         ACPI_EXCEPTION((AE_INFO, status,
 240                                         "Could not release ACPI Global Lock"));
 241                 }
 242         }
 243
 244         return_VOID;
 245 }
 246
 247 /*******************************************************************************
 248  *
 249  * FUNCTION:    acpi_ex_digits_needed
 250  *
 251  * PARAMETERS:  Value           - Value to be represented
 252  *              Base            - Base of representation
 253  *
 254  * RETURN:      The number of digits.
 255  *
 256  * DESCRIPTION: Calculate the number of digits needed to represent the Value
 257  *              in the given Base (Radix)
 258  *
 259  ******************************************************************************/
 260
 261 static u32 acpi_ex_digits_needed(acpi_integer value, u32 base)
 262 {
 263         u32 num_digits;
 264         acpi_integer current_value;
 265
 266         ACPI_FUNCTION_TRACE("ex_digits_needed");
 267
 268         /* acpi_integer is unsigned, so we don't worry about a '-' prefix */
 269
 270         if (value == 0) {
 271                 return_UINT32(1);
 272         }
 273
 274         current_value = value;
 275         num_digits = 0;
 276
 277         /* Count the digits in the requested base */
 278
 279         while (current_value) {
 280                 (void)acpi_ut_short_divide(current_value, base, &current_value,
 281                                            NULL);
 282                 num_digits++;
 283         }
 284
 285         return_UINT32(num_digits);
 286 }
 287
 288 /*******************************************************************************
 289  *
 290  * FUNCTION:    acpi_ex_eisa_id_to_string
 291  *
 292  * PARAMETERS:  numeric_id      - EISA ID to be converted
 293  *              out_string      - Where to put the converted string (8 bytes)
 294  *
 295  * RETURN:      None
 296  *
 297  * DESCRIPTION: Convert a numeric EISA ID to string representation
 298  *
 299  ******************************************************************************/
 300
 301 void acpi_ex_eisa_id_to_string(u32 numeric_id, char *out_string)
 302 {
 303         u32 eisa_id;
 304
 305         ACPI_FUNCTION_ENTRY();
 306
 307         /* Swap ID to big-endian to get contiguous bits */
 308
 309         eisa_id = acpi_ut_dword_byte_swap(numeric_id);
 310
 311         out_string[0] = (char)('@' + (((unsigned long)eisa_id >> 26) & 0x1f));
 312         out_string[1] = (char)('@' + ((eisa_id >> 21) & 0x1f));
 313         out_string[2] = (char)('@' + ((eisa_id >> 16) & 0x1f));
 314         out_string[3] = acpi_ut_hex_to_ascii_char((acpi_integer) eisa_id, 12);
 315         out_string[4] = acpi_ut_hex_to_ascii_char((acpi_integer) eisa_id, 8);
 316         out_string[5] = acpi_ut_hex_to_ascii_char((acpi_integer) eisa_id, 4);
 317         out_string[6] = acpi_ut_hex_to_ascii_char((acpi_integer) eisa_id, 0);
 318         out_string[7] = 0;
 319 }
 320
 321 /*******************************************************************************
 322  *
 323  * FUNCTION:    acpi_ex_unsigned_integer_to_string
 324  *
 325  * PARAMETERS:  Value           - Value to be converted
 326  *              out_string      - Where to put the converted string (8 bytes)
 327  *
 328  * RETURN:      None, string
 329  *
 330  * DESCRIPTION: Convert a number to string representation. Assumes string
 331  *              buffer is large enough to hold the string.
 332  *
 333  ******************************************************************************/
 334
 335 void acpi_ex_unsigned_integer_to_string(acpi_integer value, char *out_string)
 336 {
 337         u32 count;
 338         u32 digits_needed;
 339         u32 remainder;
 340
 341         ACPI_FUNCTION_ENTRY();
 342
 343         digits_needed = acpi_ex_digits_needed(value, 10);
 344         out_string[digits_needed] = 0;
 345
 346         for (count = digits_needed; count > 0; count--) {
 347                 (void)acpi_ut_short_divide(value, 10, &value, &remainder);
 348                 out_string[count - 1] = (char)('0' + remainder);
 349         }
 350 }
 351
 352 #endif