1 /****************************************************************************** 2 * 3 * Module Name: tbutils - ACPI Table utilities 4 * 5 *****************************************************************************/ 6 7 /****************************************************************************** 8 * 9 * 1. Copyright Notice 10 * 11 * Some or all of this work - Copyright (c) 1999 - 2022, 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 * Alternatively, you may choose to be licensed under the terms of the 117 * following license: 118 * 119 * Redistribution and use in source and binary forms, with or without 120 * modification, are permitted provided that the following conditions 121 * are met: 122 * 1. Redistributions of source code must retain the above copyright 123 * notice, this list of conditions, and the following disclaimer, 124 * without modification. 125 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 126 * substantially similar to the "NO WARRANTY" disclaimer below 127 * ("Disclaimer") and any redistribution must be conditioned upon 128 * including a substantially similar Disclaimer requirement for further 129 * binary redistribution. 130 * 3. Neither the names of the above-listed copyright holders nor the names 131 * of any contributors may be used to endorse or promote products derived 132 * from this software without specific prior written permission. 133 * 134 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 135 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 136 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 137 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 138 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 139 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 140 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 141 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 142 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 143 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 144 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 145 * 146 * Alternatively, you may choose to be licensed under the terms of the 147 * GNU General Public License ("GPL") version 2 as published by the Free 148 * Software Foundation. 149 * 150 *****************************************************************************/ 151 152 #include <contrib/dev/acpica/include/acpi.h> 153 #include <contrib/dev/acpica/include/accommon.h> 154 #include <contrib/dev/acpica/include/actables.h> 155 156 #define _COMPONENT ACPI_TABLES 157 ACPI_MODULE_NAME ("tbutils") 158 159 160 /* Local prototypes */ 161 162 static ACPI_PHYSICAL_ADDRESS 163 AcpiTbGetRootTableEntry ( 164 UINT8 *TableEntry, 165 UINT32 TableEntrySize); 166 167 168 #if (!ACPI_REDUCED_HARDWARE) 169 /******************************************************************************* 170 * 171 * FUNCTION: AcpiTbInitializeFacs 172 * 173 * PARAMETERS: None 174 * 175 * RETURN: Status 176 * 177 * DESCRIPTION: Create a permanent mapping for the FADT and save it in a global 178 * for accessing the Global Lock and Firmware Waking Vector 179 * 180 ******************************************************************************/ 181 182 ACPI_STATUS 183 AcpiTbInitializeFacs ( 184 void) 185 { 186 ACPI_TABLE_FACS *Facs; 187 188 189 /* If Hardware Reduced flag is set, there is no FACS */ 190 191 if (AcpiGbl_ReducedHardware) 192 { 193 AcpiGbl_FACS = NULL; 194 return (AE_OK); 195 } 196 else if (AcpiGbl_FADT.XFacs && 197 (!AcpiGbl_FADT.Facs || !AcpiGbl_Use32BitFacsAddresses)) 198 { 199 (void) AcpiGetTableByIndex (AcpiGbl_XFacsIndex, 200 ACPI_CAST_INDIRECT_PTR (ACPI_TABLE_HEADER, &Facs)); 201 AcpiGbl_FACS = Facs; 202 } 203 else if (AcpiGbl_FADT.Facs) 204 { 205 (void) AcpiGetTableByIndex (AcpiGbl_FacsIndex, 206 ACPI_CAST_INDIRECT_PTR (ACPI_TABLE_HEADER, &Facs)); 207 AcpiGbl_FACS = Facs; 208 } 209 210 /* If there is no FACS, just continue. There was already an error msg */ 211 212 return (AE_OK); 213 } 214 #endif /* !ACPI_REDUCED_HARDWARE */ 215 216 217 /******************************************************************************* 218 * 219 * FUNCTION: AcpiTbCheckDsdtHeader 220 * 221 * PARAMETERS: None 222 * 223 * RETURN: None 224 * 225 * DESCRIPTION: Quick compare to check validity of the DSDT. This will detect 226 * if the DSDT has been replaced from outside the OS and/or if 227 * the DSDT header has been corrupted. 228 * 229 ******************************************************************************/ 230 231 void 232 AcpiTbCheckDsdtHeader ( 233 void) 234 { 235 236 /* Compare original length and checksum to current values */ 237 238 if (AcpiGbl_OriginalDsdtHeader.Length != AcpiGbl_DSDT->Length || 239 AcpiGbl_OriginalDsdtHeader.Checksum != AcpiGbl_DSDT->Checksum) 240 { 241 ACPI_BIOS_ERROR ((AE_INFO, 242 "The DSDT has been corrupted or replaced - " 243 "old, new headers below")); 244 245 AcpiTbPrintTableHeader (0, &AcpiGbl_OriginalDsdtHeader); 246 AcpiTbPrintTableHeader (0, AcpiGbl_DSDT); 247 248 /* Disable further error messages */ 249 250 AcpiGbl_OriginalDsdtHeader.Length = AcpiGbl_DSDT->Length; 251 AcpiGbl_OriginalDsdtHeader.Checksum = AcpiGbl_DSDT->Checksum; 252 } 253 } 254 255 256 /******************************************************************************* 257 * 258 * FUNCTION: AcpiTbCopyDsdt 259 * 260 * PARAMETERS: TableIndex - Index of installed table to copy 261 * 262 * RETURN: The copied DSDT 263 * 264 * DESCRIPTION: Implements a subsystem option to copy the DSDT to local memory. 265 * Some very bad BIOSs are known to either corrupt the DSDT or 266 * install a new, bad DSDT. This copy works around the problem. 267 * 268 ******************************************************************************/ 269 270 ACPI_TABLE_HEADER * 271 AcpiTbCopyDsdt ( 272 UINT32 TableIndex) 273 { 274 ACPI_TABLE_HEADER *NewTable; 275 ACPI_TABLE_DESC *TableDesc; 276 277 278 TableDesc = &AcpiGbl_RootTableList.Tables[TableIndex]; 279 280 NewTable = ACPI_ALLOCATE (TableDesc->Length); 281 if (!NewTable) 282 { 283 ACPI_ERROR ((AE_INFO, "Could not copy DSDT of length 0x%X", 284 TableDesc->Length)); 285 return (NULL); 286 } 287 288 memcpy (NewTable, TableDesc->Pointer, TableDesc->Length); 289 AcpiTbUninstallTable (TableDesc); 290 291 AcpiTbInitTableDescriptor ( 292 &AcpiGbl_RootTableList.Tables[AcpiGbl_DsdtIndex], 293 ACPI_PTR_TO_PHYSADDR (NewTable), 294 ACPI_TABLE_ORIGIN_INTERNAL_VIRTUAL, NewTable); 295 296 ACPI_INFO (( 297 "Forced DSDT copy: length 0x%05X copied locally, original unmapped", 298 NewTable->Length)); 299 300 return (NewTable); 301 } 302 303 304 /******************************************************************************* 305 * 306 * FUNCTION: AcpiTbGetRootTableEntry 307 * 308 * PARAMETERS: TableEntry - Pointer to the RSDT/XSDT table entry 309 * TableEntrySize - sizeof 32 or 64 (RSDT or XSDT) 310 * 311 * RETURN: Physical address extracted from the root table 312 * 313 * DESCRIPTION: Get one root table entry. Handles 32-bit and 64-bit cases on 314 * both 32-bit and 64-bit platforms 315 * 316 * NOTE: ACPI_PHYSICAL_ADDRESS is 32-bit on 32-bit platforms, 64-bit on 317 * 64-bit platforms. 318 * 319 ******************************************************************************/ 320 321 static ACPI_PHYSICAL_ADDRESS 322 AcpiTbGetRootTableEntry ( 323 UINT8 *TableEntry, 324 UINT32 TableEntrySize) 325 { 326 UINT64 Address64; 327 328 329 /* 330 * Get the table physical address (32-bit for RSDT, 64-bit for XSDT): 331 * Note: Addresses are 32-bit aligned (not 64) in both RSDT and XSDT 332 */ 333 if (TableEntrySize == ACPI_RSDT_ENTRY_SIZE) 334 { 335 /* 336 * 32-bit platform, RSDT: Return 32-bit table entry 337 * 64-bit platform, RSDT: Expand 32-bit to 64-bit and return 338 */ 339 return ((ACPI_PHYSICAL_ADDRESS) (*ACPI_CAST_PTR ( 340 UINT32, TableEntry))); 341 } 342 else 343 { 344 /* 345 * 32-bit platform, XSDT: Truncate 64-bit to 32-bit and return 346 * 64-bit platform, XSDT: Move (unaligned) 64-bit to local, 347 * return 64-bit 348 */ 349 ACPI_MOVE_64_TO_64 (&Address64, TableEntry); 350 351 #if ACPI_MACHINE_WIDTH == 32 352 if (Address64 > ACPI_UINT32_MAX) 353 { 354 /* Will truncate 64-bit address to 32 bits, issue warning */ 355 356 ACPI_BIOS_WARNING ((AE_INFO, 357 "64-bit Physical Address in XSDT is too large (0x%8.8X%8.8X)," 358 " truncating", 359 ACPI_FORMAT_UINT64 (Address64))); 360 } 361 #endif 362 return ((ACPI_PHYSICAL_ADDRESS) (Address64)); 363 } 364 } 365 366 367 /******************************************************************************* 368 * 369 * FUNCTION: AcpiTbParseRootTable 370 * 371 * PARAMETERS: RsdpAddress - Pointer to the RSDP 372 * 373 * RETURN: Status 374 * 375 * DESCRIPTION: This function is called to parse the Root System Description 376 * Table (RSDT or XSDT) 377 * 378 * NOTE: Tables are mapped (not copied) for efficiency. The FACS must 379 * be mapped and cannot be copied because it contains the actual 380 * memory location of the ACPI Global Lock. 381 * 382 ******************************************************************************/ 383 384 ACPI_STATUS ACPI_INIT_FUNCTION 385 AcpiTbParseRootTable ( 386 ACPI_PHYSICAL_ADDRESS RsdpAddress) 387 { 388 ACPI_TABLE_RSDP *Rsdp; 389 UINT32 TableEntrySize; 390 UINT32 i; 391 UINT32 TableCount; 392 ACPI_TABLE_HEADER *Table; 393 ACPI_PHYSICAL_ADDRESS Address; 394 UINT32 Length; 395 UINT8 *TableEntry; 396 ACPI_STATUS Status; 397 UINT32 TableIndex; 398 399 400 ACPI_FUNCTION_TRACE (TbParseRootTable); 401 402 403 /* Map the entire RSDP and extract the address of the RSDT or XSDT */ 404 405 Rsdp = AcpiOsMapMemory (RsdpAddress, sizeof (ACPI_TABLE_RSDP)); 406 if (!Rsdp) 407 { 408 return_ACPI_STATUS (AE_NO_MEMORY); 409 } 410 411 AcpiTbPrintTableHeader (RsdpAddress, 412 ACPI_CAST_PTR (ACPI_TABLE_HEADER, Rsdp)); 413 414 /* Use XSDT if present and not overridden. Otherwise, use RSDT */ 415 416 if ((Rsdp->Revision > 1) && 417 Rsdp->XsdtPhysicalAddress && 418 !AcpiGbl_DoNotUseXsdt) 419 { 420 /* 421 * RSDP contains an XSDT (64-bit physical addresses). We must use 422 * the XSDT if the revision is > 1 and the XSDT pointer is present, 423 * as per the ACPI specification. 424 */ 425 Address = (ACPI_PHYSICAL_ADDRESS) Rsdp->XsdtPhysicalAddress; 426 TableEntrySize = ACPI_XSDT_ENTRY_SIZE; 427 } 428 else 429 { 430 /* Root table is an RSDT (32-bit physical addresses) */ 431 432 Address = (ACPI_PHYSICAL_ADDRESS) Rsdp->RsdtPhysicalAddress; 433 TableEntrySize = ACPI_RSDT_ENTRY_SIZE; 434 } 435 436 /* 437 * It is not possible to map more than one entry in some environments, 438 * so unmap the RSDP here before mapping other tables 439 */ 440 AcpiOsUnmapMemory (Rsdp, sizeof (ACPI_TABLE_RSDP)); 441 442 /* Map the RSDT/XSDT table header to get the full table length */ 443 444 Table = AcpiOsMapMemory (Address, sizeof (ACPI_TABLE_HEADER)); 445 if (!Table) 446 { 447 return_ACPI_STATUS (AE_NO_MEMORY); 448 } 449 450 AcpiTbPrintTableHeader (Address, Table); 451 452 /* 453 * Validate length of the table, and map entire table. 454 * Minimum length table must contain at least one entry. 455 */ 456 Length = Table->Length; 457 AcpiOsUnmapMemory (Table, sizeof (ACPI_TABLE_HEADER)); 458 459 if (Length < (sizeof (ACPI_TABLE_HEADER) + TableEntrySize)) 460 { 461 ACPI_BIOS_ERROR ((AE_INFO, 462 "Invalid table length 0x%X in RSDT/XSDT", Length)); 463 return_ACPI_STATUS (AE_INVALID_TABLE_LENGTH); 464 } 465 466 Table = AcpiOsMapMemory (Address, Length); 467 if (!Table) 468 { 469 return_ACPI_STATUS (AE_NO_MEMORY); 470 } 471 472 /* Validate the root table checksum */ 473 474 Status = AcpiTbVerifyChecksum (Table, Length); 475 if (ACPI_FAILURE (Status)) 476 { 477 AcpiOsUnmapMemory (Table, Length); 478 return_ACPI_STATUS (Status); 479 } 480 481 /* Get the number of entries and pointer to first entry */ 482 483 TableCount = (UINT32) ((Table->Length - sizeof (ACPI_TABLE_HEADER)) / 484 TableEntrySize); 485 TableEntry = ACPI_ADD_PTR (UINT8, Table, sizeof (ACPI_TABLE_HEADER)); 486 487 /* Initialize the root table array from the RSDT/XSDT */ 488 489 for (i = 0; i < TableCount; i++) 490 { 491 /* Get the table physical address (32-bit for RSDT, 64-bit for XSDT) */ 492 493 Address = AcpiTbGetRootTableEntry (TableEntry, TableEntrySize); 494 495 /* Skip NULL entries in RSDT/XSDT */ 496 497 if (!Address) 498 { 499 goto NextTable; 500 } 501 502 Status = AcpiTbInstallStandardTable (Address, 503 ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL, NULL, FALSE, TRUE, 504 &TableIndex); 505 506 if (ACPI_SUCCESS (Status) && 507 ACPI_COMPARE_NAMESEG ( 508 &AcpiGbl_RootTableList.Tables[TableIndex].Signature, 509 ACPI_SIG_FADT)) 510 { 511 AcpiGbl_FadtIndex = TableIndex; 512 AcpiTbParseFadt (); 513 } 514 515 NextTable: 516 517 TableEntry += TableEntrySize; 518 } 519 520 AcpiOsUnmapMemory (Table, Length); 521 return_ACPI_STATUS (AE_OK); 522 } 523 524 525 /******************************************************************************* 526 * 527 * FUNCTION: AcpiTbGetTable 528 * 529 * PARAMETERS: TableDesc - Table descriptor 530 * OutTable - Where the pointer to the table is returned 531 * 532 * RETURN: Status and pointer to the requested table 533 * 534 * DESCRIPTION: Increase a reference to a table descriptor and return the 535 * validated table pointer. 536 * If the table descriptor is an entry of the root table list, 537 * this API must be invoked with ACPI_MTX_TABLES acquired. 538 * 539 ******************************************************************************/ 540 541 ACPI_STATUS 542 AcpiTbGetTable ( 543 ACPI_TABLE_DESC *TableDesc, 544 ACPI_TABLE_HEADER **OutTable) 545 { 546 ACPI_STATUS Status; 547 548 549 ACPI_FUNCTION_TRACE (AcpiTbGetTable); 550 551 552 if (TableDesc->ValidationCount == 0) 553 { 554 /* Table need to be "VALIDATED" */ 555 556 Status = AcpiTbValidateTable (TableDesc); 557 if (ACPI_FAILURE (Status)) 558 { 559 return_ACPI_STATUS (Status); 560 } 561 } 562 563 if (TableDesc->ValidationCount < ACPI_MAX_TABLE_VALIDATIONS) 564 { 565 TableDesc->ValidationCount++; 566 567 /* 568 * Detect ValidationCount overflows to ensure that the warning 569 * message will only be printed once. 570 */ 571 if (TableDesc->ValidationCount >= ACPI_MAX_TABLE_VALIDATIONS) 572 { 573 ACPI_WARNING((AE_INFO, 574 "Table %p, Validation count overflows\n", TableDesc)); 575 } 576 } 577 578 *OutTable = TableDesc->Pointer; 579 return_ACPI_STATUS (AE_OK); 580 } 581 582 583 /******************************************************************************* 584 * 585 * FUNCTION: AcpiTbPutTable 586 * 587 * PARAMETERS: TableDesc - Table descriptor 588 * 589 * RETURN: None 590 * 591 * DESCRIPTION: Decrease a reference to a table descriptor and release the 592 * validated table pointer if no references. 593 * If the table descriptor is an entry of the root table list, 594 * this API must be invoked with ACPI_MTX_TABLES acquired. 595 * 596 ******************************************************************************/ 597 598 void 599 AcpiTbPutTable ( 600 ACPI_TABLE_DESC *TableDesc) 601 { 602 603 ACPI_FUNCTION_TRACE (AcpiTbPutTable); 604 605 606 if (TableDesc->ValidationCount < ACPI_MAX_TABLE_VALIDATIONS) 607 { 608 TableDesc->ValidationCount--; 609 610 /* 611 * Detect ValidationCount underflows to ensure that the warning 612 * message will only be printed once. 613 */ 614 if (TableDesc->ValidationCount >= ACPI_MAX_TABLE_VALIDATIONS) 615 { 616 ACPI_WARNING ((AE_INFO, 617 "Table %p, Validation count underflows\n", TableDesc)); 618 return_VOID; 619 } 620 } 621 622 if (TableDesc->ValidationCount == 0) 623 { 624 /* Table need to be "INVALIDATED" */ 625 626 AcpiTbInvalidateTable (TableDesc); 627 } 628 629 return_VOID; 630 } 631