reactos/drivers/bus/acpi/acpica/events/evglock.c

   1 /******************************************************************************
   2  *
   3  * Module Name: evglock - Global Lock support
   4  *
   5  *****************************************************************************/
   6
   7 /******************************************************************************
   8  *
   9  * 1. Copyright Notice
  10  *
  11  * Some or all of this work - Copyright (c) 1999 - 2014, Intel Corp.
  12  * All rights reserved.
  13  *
  14  * 2. License
  15  *
  16  * 2.1. This is your license from Intel Corp. under its intellectual property
  17  * rights. You may have additional license terms from the party that provided
  18  * you this software, covering your right to use that party's intellectual
  19  * property rights.
  20  *
  21  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
  22  * copy of the source code appearing in this file ("Covered Code") an
  23  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
  24  * base code distributed originally by Intel ("Original Intel Code") to copy,
  25  * make derivatives, distribute, use and display any portion of the Covered
  26  * Code in any form, with the right to sublicense such rights; and
  27  *
  28  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
  29  * license (with the right to sublicense), under only those claims of Intel
  30  * patents that are infringed by the Original Intel Code, to make, use, sell,
  31  * offer to sell, and import the Covered Code and derivative works thereof
  32  * solely to the minimum extent necessary to exercise the above copyright
  33  * license, and in no event shall the patent license extend to any additions
  34  * to or modifications of the Original Intel Code. No other license or right
  35  * is granted directly or by implication, estoppel or otherwise;
  36  *
  37  * The above copyright and patent license is granted only if the following
  38  * conditions are met:
  39  *
  40  * 3. Conditions
  41  *
  42  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
  43  * Redistribution of source code of any substantial portion of the Covered
  44  * Code or modification with rights to further distribute source must include
  45  * the above Copyright Notice, the above License, this list of Conditions,
  46  * and the following Disclaimer and Export Compliance provision. In addition,
  47  * Licensee must cause all Covered Code to which Licensee contributes to
  48  * contain a file documenting the changes Licensee made to create that Covered
  49  * Code and the date of any change. Licensee must include in that file the
  50  * documentation of any changes made by any predecessor Licensee. Licensee
  51  * must include a prominent statement that the modification is derived,
  52  * directly or indirectly, from Original Intel Code.
  53  *
  54  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
  55  * Redistribution of source code of any substantial portion of the Covered
  56  * Code or modification without rights to further distribute source must
  57  * include the following Disclaimer and Export Compliance provision in the
  58  * documentation and/or other materials provided with distribution. In
  59  * addition, Licensee may not authorize further sublicense of source of any
  60  * portion of the Covered Code, and must include terms to the effect that the
  61  * license from Licensee to its licensee is limited to the intellectual
  62  * property embodied in the software Licensee provides to its licensee, and
  63  * not to intellectual property embodied in modifications its licensee may
  64  * make.
  65  *
  66  * 3.3. Redistribution of Executable. Redistribution in executable form of any
  67  * substantial portion of the Covered Code or modification must reproduce the
  68  * above Copyright Notice, and the following Disclaimer and Export Compliance
  69  * provision in the documentation and/or other materials provided with the
  70  * distribution.
  71  *
  72  * 3.4. Intel retains all right, title, and interest in and to the Original
  73  * Intel Code.
  74  *
  75  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
  76  * Intel shall be used in advertising or otherwise to promote the sale, use or
  77  * other dealings in products derived from or relating to the Covered Code
  78  * without prior written authorization from Intel.
  79  *
  80  * 4. Disclaimer and Export Compliance
  81  *
  82  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
  83  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
  84  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
  85  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
  86  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
  87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
  88  * PARTICULAR PURPOSE.
  89  *
  90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
  91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
  92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
  93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
  94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
  95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
  96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
  97  * LIMITED REMEDY.
  98  *
  99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
 100  * software or system incorporating such software without first obtaining any
 101  * required license or other approval from the U. S. Department of Commerce or
 102  * any other agency or department of the United States Government. In the
 103  * event Licensee exports any such software from the United States or
 104  * re-exports any such software from a foreign destination, Licensee shall
 105  * ensure that the distribution and export/re-export of the software is in
 106  * compliance with all laws, regulations, orders, or other restrictions of the
 107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
 108  * any of its subsidiaries will export/re-export any technical data, process,
 109  * software, or service, directly or indirectly, to any country for which the
 110  * United States government or any agency thereof requires an export license,
 111  * other governmental approval, or letter of assurance, without first obtaining
 112  * such license, approval or letter.
 113  *
 114  *****************************************************************************/
 115
 116 #include "acpi.h"
 117 #include "accommon.h"
 118 #include "acevents.h"
 119 #include "acinterp.h"
 120
 121 #define _COMPONENT          ACPI_EVENTS
 122         ACPI_MODULE_NAME    ("evglock")
 123 #if ACPI_REDUCED_HARDWARE
 124 #error
 125 #endif
 126 #if (!ACPI_REDUCED_HARDWARE) /* Entire module */
 127
 128 /* Local prototypes */
 129
 130 static UINT32
 131 AcpiEvGlobalLockHandler (
 132     void                    *Context);
 133
 134
 135 /*******************************************************************************
 136  *
 137  * FUNCTION:    AcpiEvInitGlobalLockHandler
 138  *
 139  * PARAMETERS:  None
 140  *
 141  * RETURN:      Status
 142  *
 143  * DESCRIPTION: Install a handler for the global lock release event
 144  *
 145  ******************************************************************************/
 146
 147 ACPI_STATUS
 148 AcpiEvInitGlobalLockHandler (
 149     void)
 150 {
 151     ACPI_STATUS             Status;
 152
 153
 154     ACPI_FUNCTION_TRACE (EvInitGlobalLockHandler);
 155
 156
 157     /* If Hardware Reduced flag is set, there is no global lock */
 158
 159     if (AcpiGbl_ReducedHardware)
 160     {
 161         return_ACPI_STATUS (AE_OK);
 162     }
 163
 164     /* Attempt installation of the global lock handler */
 165
 166     Status = AcpiInstallFixedEventHandler (ACPI_EVENT_GLOBAL,
 167                 AcpiEvGlobalLockHandler, NULL);
 168
 169     /*
 170      * If the global lock does not exist on this platform, the attempt to
 171      * enable GBL_STATUS will fail (the GBL_ENABLE bit will not stick).
 172      * Map to AE_OK, but mark global lock as not present. Any attempt to
 173      * actually use the global lock will be flagged with an error.
 174      */
 175     AcpiGbl_GlobalLockPresent = FALSE;
 176     if (Status == AE_NO_HARDWARE_RESPONSE)
 177     {
 178         ACPI_ERROR ((AE_INFO,
 179             "No response from Global Lock hardware, disabling lock"));
 180
 181         return_ACPI_STATUS (AE_OK);
 182     }
 183
 184     Status = AcpiOsCreateLock (&AcpiGbl_GlobalLockPendingLock);
 185     if (ACPI_FAILURE (Status))
 186     {
 187         return_ACPI_STATUS (Status);
 188     }
 189
 190     AcpiGbl_GlobalLockPending = FALSE;
 191     AcpiGbl_GlobalLockPresent = TRUE;
 192     return_ACPI_STATUS (Status);
 193 }
 194
 195
 196 /*******************************************************************************
 197  *
 198  * FUNCTION:    AcpiEvRemoveGlobalLockHandler
 199  *
 200  * PARAMETERS:  None
 201  *
 202  * RETURN:      Status
 203  *
 204  * DESCRIPTION: Remove the handler for the Global Lock
 205  *
 206  ******************************************************************************/
 207
 208 ACPI_STATUS
 209 AcpiEvRemoveGlobalLockHandler (
 210     void)
 211 {
 212     ACPI_STATUS             Status;
 213
 214
 215     ACPI_FUNCTION_TRACE (EvRemoveGlobalLockHandler);
 216
 217     AcpiGbl_GlobalLockPresent = FALSE;
 218     Status = AcpiRemoveFixedEventHandler (ACPI_EVENT_GLOBAL,
 219                 AcpiEvGlobalLockHandler);
 220
 221     AcpiOsDeleteLock (AcpiGbl_GlobalLockPendingLock);
 222     return_ACPI_STATUS (Status);
 223 }
 224
 225
 226 /*******************************************************************************
 227  *
 228  * FUNCTION:    AcpiEvGlobalLockHandler
 229  *
 230  * PARAMETERS:  Context         - From thread interface, not used
 231  *
 232  * RETURN:      ACPI_INTERRUPT_HANDLED
 233  *
 234  * DESCRIPTION: Invoked directly from the SCI handler when a global lock
 235  *              release interrupt occurs. If there is actually a pending
 236  *              request for the lock, signal the waiting thread.
 237  *
 238  ******************************************************************************/
 239
 240 static UINT32
 241 AcpiEvGlobalLockHandler (
 242     void                    *Context)
 243 {
 244     ACPI_STATUS             Status;
 245     ACPI_CPU_FLAGS          Flags;
 246
 247
 248     Flags = AcpiOsAcquireLock (AcpiGbl_GlobalLockPendingLock);
 249
 250     /*
 251      * If a request for the global lock is not actually pending,
 252      * we are done. This handles "spurious" global lock interrupts
 253      * which are possible (and have been seen) with bad BIOSs.
 254      */
 255     if (!AcpiGbl_GlobalLockPending)
 256     {
 257         goto CleanupAndExit;
 258     }
 259
 260     /*
 261      * Send a unit to the global lock semaphore. The actual acquisition
 262      * of the global lock will be performed by the waiting thread.
 263      */
 264     Status = AcpiOsSignalSemaphore (AcpiGbl_GlobalLockSemaphore, 1);
 265     if (ACPI_FAILURE (Status))
 266     {
 267         ACPI_ERROR ((AE_INFO, "Could not signal Global Lock semaphore"));
 268     }
 269
 270     AcpiGbl_GlobalLockPending = FALSE;
 271
 272
 273 CleanupAndExit:
 274
 275     AcpiOsReleaseLock (AcpiGbl_GlobalLockPendingLock, Flags);
 276     return (ACPI_INTERRUPT_HANDLED);
 277 }
 278
 279
 280 /******************************************************************************
 281  *
 282  * FUNCTION:    AcpiEvAcquireGlobalLock
 283  *
 284  * PARAMETERS:  Timeout         - Max time to wait for the lock, in millisec.
 285  *
 286  * RETURN:      Status
 287  *
 288  * DESCRIPTION: Attempt to gain ownership of the Global Lock.
 289  *
 290  * MUTEX:       Interpreter must be locked
 291  *
 292  * Note: The original implementation allowed multiple threads to "acquire" the
 293  * Global Lock, and the OS would hold the lock until the last thread had
 294  * released it. However, this could potentially starve the BIOS out of the
 295  * lock, especially in the case where there is a tight handshake between the
 296  * Embedded Controller driver and the BIOS. Therefore, this implementation
 297  * allows only one thread to acquire the HW Global Lock at a time, and makes
 298  * the global lock appear as a standard mutex on the OS side.
 299  *
 300  *****************************************************************************/
 301
 302 ACPI_STATUS
 303 AcpiEvAcquireGlobalLock (
 304     UINT16                  Timeout)
 305 {
 306     ACPI_CPU_FLAGS          Flags;
 307     ACPI_STATUS             Status;
 308     BOOLEAN                 Acquired = FALSE;
 309
 310
 311     ACPI_FUNCTION_TRACE (EvAcquireGlobalLock);
 312
 313
 314     /*
 315      * Only one thread can acquire the GL at a time, the GlobalLockMutex
 316      * enforces this. This interface releases the interpreter if we must wait.
 317      */
 318     Status = AcpiExSystemWaitMutex (AcpiGbl_GlobalLockMutex->Mutex.OsMutex,
 319                 Timeout);
 320     if (ACPI_FAILURE (Status))
 321     {
 322         return_ACPI_STATUS (Status);
 323     }
 324
 325     /*
 326      * Update the global lock handle and check for wraparound. The handle is
 327      * only used for the external global lock interfaces, but it is updated
 328      * here to properly handle the case where a single thread may acquire the
 329      * lock via both the AML and the AcpiAcquireGlobalLock interfaces. The
 330      * handle is therefore updated on the first acquire from a given thread
 331      * regardless of where the acquisition request originated.
 332      */
 333     AcpiGbl_GlobalLockHandle++;
 334     if (AcpiGbl_GlobalLockHandle == 0)
 335     {
 336         AcpiGbl_GlobalLockHandle = 1;
 337     }
 338
 339     /*
 340      * Make sure that a global lock actually exists. If not, just
 341      * treat the lock as a standard mutex.
 342      */
 343     if (!AcpiGbl_GlobalLockPresent)
 344     {
 345         AcpiGbl_GlobalLockAcquired = TRUE;
 346         return_ACPI_STATUS (AE_OK);
 347     }
 348
 349     Flags = AcpiOsAcquireLock (AcpiGbl_GlobalLockPendingLock);
 350
 351     do
 352     {
 353         /* Attempt to acquire the actual hardware lock */
 354
 355         ACPI_ACQUIRE_GLOBAL_LOCK (AcpiGbl_FACS, Acquired);
 356         if (Acquired)
 357         {
 358             AcpiGbl_GlobalLockAcquired = TRUE;
 359             ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
 360                 "Acquired hardware Global Lock\n"));
 361             break;
 362         }
 363
 364         /*
 365          * Did not get the lock. The pending bit was set above, and
 366          * we must now wait until we receive the global lock
 367          * released interrupt.
 368          */
 369         AcpiGbl_GlobalLockPending = TRUE;
 370         AcpiOsReleaseLock (AcpiGbl_GlobalLockPendingLock, Flags);
 371
 372         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
 373             "Waiting for hardware Global Lock\n"));
 374
 375         /*
 376          * Wait for handshake with the global lock interrupt handler.
 377          * This interface releases the interpreter if we must wait.
 378          */
 379         Status = AcpiExSystemWaitSemaphore (AcpiGbl_GlobalLockSemaphore,
 380                     ACPI_WAIT_FOREVER);
 381
 382         Flags = AcpiOsAcquireLock (AcpiGbl_GlobalLockPendingLock);
 383
 384     } while (ACPI_SUCCESS (Status));
 385
 386     AcpiGbl_GlobalLockPending = FALSE;
 387     AcpiOsReleaseLock (AcpiGbl_GlobalLockPendingLock, Flags);
 388
 389     return_ACPI_STATUS (Status);
 390 }
 391
 392
 393 /*******************************************************************************
 394  *
 395  * FUNCTION:    AcpiEvReleaseGlobalLock
 396  *
 397  * PARAMETERS:  None
 398  *
 399  * RETURN:      Status
 400  *
 401  * DESCRIPTION: Releases ownership of the Global Lock.
 402  *
 403  ******************************************************************************/
 404
 405 ACPI_STATUS
 406 AcpiEvReleaseGlobalLock (
 407     void)
 408 {
 409     BOOLEAN                 Pending = FALSE;
 410     ACPI_STATUS             Status = AE_OK;
 411
 412
 413     ACPI_FUNCTION_TRACE (EvReleaseGlobalLock);
 414
 415
 416     /* Lock must be already acquired */
 417
 418     if (!AcpiGbl_GlobalLockAcquired)
 419     {
 420         ACPI_WARNING ((AE_INFO,
 421             "Cannot release the ACPI Global Lock, it has not been acquired"));
 422         return_ACPI_STATUS (AE_NOT_ACQUIRED);
 423     }
 424
 425     if (AcpiGbl_GlobalLockPresent)
 426     {
 427         /* Allow any thread to release the lock */
 428
 429         ACPI_RELEASE_GLOBAL_LOCK (AcpiGbl_FACS, Pending);
 430
 431         /*
 432          * If the pending bit was set, we must write GBL_RLS to the control
 433          * register
 434          */
 435         if (Pending)
 436         {
 437             Status = AcpiWriteBitRegister (
 438                         ACPI_BITREG_GLOBAL_LOCK_RELEASE, ACPI_ENABLE_EVENT);
 439         }
 440
 441         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Released hardware Global Lock\n"));
 442     }
 443
 444     AcpiGbl_GlobalLockAcquired = FALSE;
 445
 446     /* Release the local GL mutex */
 447
 448     AcpiOsReleaseMutex (AcpiGbl_GlobalLockMutex->Mutex.OsMutex);
 449     return_ACPI_STATUS (Status);
 450 }
 451
 452 #endif /* !ACPI_REDUCED_HARDWARE */