xref: /reactos/drivers/bus/acpi/busmgr/utils.c (revision 84344399)
1 /*
2  *  acpi_utils.c - ACPI Utility Functions ($Revision: 10 $)
3  *
4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  *
7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License as published by
11  *  the Free Software Foundation; either version 2 of the License, or (at
12  *  your option) any later version.
13  *
14  *  This program is distributed in the hope that it will be useful, but
15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  *  General Public License for more details.
18  *
19  *  You should have received a copy of the GNU General Public License along
20  *  with this program; if not, write to the Free Software Foundation, Inc.,
21  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22  *
23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24  */
25 
26 #include <precomp.h>
27 #include <ntstrsafe.h>
28 
29 #define NDEBUG
30 #include <debug.h>
31 
32  /* Modified for ReactOS and latest ACPICA
33   * Copyright (C)2009  Samuel Serapion
34   */
35 
36 #define _COMPONENT		ACPI_BUS_COMPONENT
37 ACPI_MODULE_NAME		("acpi_utils")
38 
39 static void
40 acpi_util_eval_error(ACPI_HANDLE h, ACPI_STRING p, ACPI_STATUS s)
41 {
42 #ifdef ACPI_DEBUG_OUTPUT
43 	char prefix[80] = {'\0'};
44 	ACPI_BUFFER buffer = {sizeof(prefix), prefix};
45 	AcpiGetName(h, ACPI_FULL_PATHNAME, &buffer);
46 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluate [%s.%s]: %s\n",
47 		(char *) prefix, p, AcpiFormatException(s)));
48 #else
49 	return;
50 #endif
51 }
52 
53 
54 /* --------------------------------------------------------------------------
55                             Object Evaluation Helpers
56    -------------------------------------------------------------------------- */
57 
58 
59 ACPI_STATUS
60 acpi_extract_package (
61 	ACPI_OBJECT	*package,
62 	ACPI_BUFFER	*format,
63 	ACPI_BUFFER	*buffer)
64 {
65 	UINT32			size_required = 0;
66 	UINT32			tail_offset = 0;
67 	char			*format_string = NULL;
68 	UINT32			format_count = 0;
69 	UINT32			i = 0;
70 	UINT8			*head = NULL;
71 	UINT8			*tail = NULL;
72 
73 	if (!package || (package->Type != ACPI_TYPE_PACKAGE) || (package->Package.Count < 1)) {
74 		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Invalid 'package' argument\n"));
75 		return_ACPI_STATUS(AE_BAD_PARAMETER);
76 	}
77 
78 	if (!format || !format->Pointer || (format->Length < 1)) {
79 		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Invalid 'format' argument\n"));
80 		return_ACPI_STATUS(AE_BAD_PARAMETER);
81 	}
82 
83 	if (!buffer) {
84 		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Invalid 'buffer' argument\n"));
85 		return_ACPI_STATUS(AE_BAD_PARAMETER);
86 	}
87 
88 	format_count = (format->Length/sizeof(char)) - 1;
89 	if (format_count > package->Package.Count) {
90 		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Format specifies more objects [%d] than exist in package [%d].", format_count, package->package.count));
91 		return_ACPI_STATUS(AE_BAD_DATA);
92 	}
93 
94 	format_string = format->Pointer;
95 
96 	/*
97 	 * Calculate size_required.
98 	 */
99 	for (i=0; i<format_count; i++) {
100 
101 		ACPI_OBJECT *element = &(package->Package.Elements[i]);
102 
103 		if (!element) {
104 			return_ACPI_STATUS(AE_BAD_DATA);
105 		}
106 
107 		switch (element->Type) {
108 
109 		case ACPI_TYPE_INTEGER:
110 			switch (format_string[i]) {
111 			case 'N':
112 				size_required += sizeof(ACPI_INTEGER);
113 				tail_offset += sizeof(ACPI_INTEGER);
114 				break;
115 			case 'S':
116 				size_required += sizeof(char*) + sizeof(ACPI_INTEGER) + sizeof(char);
117 				tail_offset += sizeof(char*);
118 				break;
119 			default:
120 				ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Invalid package element [%d]: got number, expecting [%c].\n", i, format_string[i]));
121 				return_ACPI_STATUS(AE_BAD_DATA);
122 				break;
123 			}
124 			break;
125 
126 		case ACPI_TYPE_STRING:
127 		case ACPI_TYPE_BUFFER:
128 			switch (format_string[i]) {
129 			case 'S':
130 				size_required += sizeof(char*) + (element->String.Length * sizeof(char)) + sizeof(char);
131 				tail_offset += sizeof(char*);
132 				break;
133 			case 'B':
134 				size_required += sizeof(UINT8*) + (element->Buffer.Length * sizeof(UINT8));
135 				tail_offset += sizeof(UINT8*);
136 				break;
137 			default:
138 				ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Invalid package element [%d] got string/buffer, expecting [%c].\n", i, format_string[i]));
139 				return_ACPI_STATUS(AE_BAD_DATA);
140 				break;
141 			}
142 			break;
143 
144 		case ACPI_TYPE_PACKAGE:
145 		default:
146 			ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unsupported element at index=%d\n", i));
147 			/* TBD: handle nested packages... */
148 			return_ACPI_STATUS(AE_SUPPORT);
149 			break;
150 		}
151 	}
152 
153 	/*
154 	 * Validate output buffer.
155 	 */
156 	if (buffer->Length < size_required) {
157 		buffer->Length = size_required;
158 		return_ACPI_STATUS(AE_BUFFER_OVERFLOW);
159 	}
160 	else if (buffer->Length != size_required || !buffer->Pointer) {
161 		return_ACPI_STATUS(AE_BAD_PARAMETER);
162 	}
163 
164 	head = buffer->Pointer;
165 	tail = ((PUCHAR)buffer->Pointer) + tail_offset;
166 
167 	/*
168 	 * Extract package data.
169 	 */
170 	for (i=0; i<format_count; i++) {
171 
172 		UINT8 **pointer = NULL;
173 		ACPI_OBJECT *element = &(package->Package.Elements[i]);
174 
175 		if (!element) {
176 			return_ACPI_STATUS(AE_BAD_DATA);
177 		}
178 
179 		switch (element->Type) {
180 
181 		case ACPI_TYPE_INTEGER:
182 			switch (format_string[i]) {
183 			case 'N':
184 				*((ACPI_INTEGER*)head) = element->Integer.Value;
185 				head += sizeof(ACPI_INTEGER);
186 				break;
187 			case 'S':
188 				pointer = (UINT8**)head;
189 				*pointer = tail;
190 				*((ACPI_INTEGER*)tail) = element->Integer.Value;
191 				head += sizeof(ACPI_INTEGER*);
192 				tail += sizeof(ACPI_INTEGER);
193 				/* NULL terminate string */
194 				*tail = (char)0;
195 				tail += sizeof(char);
196 				break;
197 			default:
198 				/* Should never get here */
199 				break;
200 			}
201 			break;
202 
203 		case ACPI_TYPE_STRING:
204 		case ACPI_TYPE_BUFFER:
205 			switch (format_string[i]) {
206 			case 'S':
207 				pointer = (UINT8**)head;
208 				*pointer = tail;
209 				memcpy(tail, element->String.Pointer, element->String.Length);
210 				head += sizeof(char*);
211 				tail += element->String.Length * sizeof(char);
212 				/* NULL terminate string */
213 				*tail = (char)0;
214 				tail += sizeof(char);
215 				break;
216 			case 'B':
217 				pointer = (UINT8**)head;
218 				*pointer = tail;
219 				memcpy(tail, element->Buffer.Pointer, element->Buffer.Length);
220 				head += sizeof(UINT8*);
221 				tail += element->Buffer.Length * sizeof(UINT8);
222 				break;
223 			default:
224 				/* Should never get here */
225 				break;
226 			}
227 			break;
228 
229 		case ACPI_TYPE_PACKAGE:
230 			/* TBD: handle nested packages... */
231 		default:
232 			/* Should never get here */
233 			break;
234 		}
235 	}
236 
237 	return_ACPI_STATUS(AE_OK);
238 }
239 
240 
241 ACPI_STATUS
242 acpi_evaluate_integer (
243 	ACPI_HANDLE		handle,
244 	ACPI_STRING		pathname,
245 	ACPI_OBJECT_LIST	*arguments,
246 	unsigned long long		*data)
247 {
248 	ACPI_STATUS             status = AE_OK;
249 	ACPI_OBJECT	element;
250 	ACPI_BUFFER	buffer = {sizeof(ACPI_OBJECT), &element};
251 
252 	ACPI_FUNCTION_TRACE("acpi_evaluate_integer");
253 
254 	if (!data)
255 		return_ACPI_STATUS(AE_BAD_PARAMETER);
256 
257 	status = AcpiEvaluateObject(handle, pathname, arguments, &buffer);
258 	if (ACPI_FAILURE(status)) {
259 		acpi_util_eval_error(handle, pathname, status);
260 		return_ACPI_STATUS(status);
261 	}
262 
263 	if (element.Type != ACPI_TYPE_INTEGER) {
264 		acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
265 		return_ACPI_STATUS(AE_BAD_DATA);
266 	}
267 
268 	*data = element.Integer.Value;
269 
270 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%lu]\n", *data));
271 
272 	return_ACPI_STATUS(AE_OK);
273 }
274 
275 
276 ACPI_STATUS
277 acpi_evaluate_reference (
278 	ACPI_HANDLE		handle,
279 	ACPI_STRING		pathname,
280 	ACPI_OBJECT_LIST	*arguments,
281 	struct acpi_handle_list	*list)
282 {
283 	ACPI_STATUS		status = AE_OK;
284 	ACPI_OBJECT	*package = NULL;
285 	ACPI_OBJECT	*element = NULL;
286 	ACPI_BUFFER	buffer = {ACPI_ALLOCATE_BUFFER, NULL};
287 	UINT32			i = 0;
288 
289 	ACPI_FUNCTION_TRACE("acpi_evaluate_reference");
290 
291 	if (!list) {
292 		return_ACPI_STATUS(AE_BAD_PARAMETER);
293 	}
294 
295 	/* Evaluate object. */
296 
297 	status = AcpiEvaluateObject(handle, pathname, arguments, &buffer);
298 	if (ACPI_FAILURE(status))
299 		goto end;
300 
301 	package = (ACPI_OBJECT *) buffer.Pointer;
302 
303 	if ((buffer.Length == 0) || !package) {
304 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
305 			"No return object (len %X ptr %p)\n",
306 			buffer.Length, package));
307 		status = AE_BAD_DATA;
308 		acpi_util_eval_error(handle, pathname, status);
309 		goto end;
310 	}
311 	if (package->Type != ACPI_TYPE_PACKAGE) {
312 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
313 			"Expecting a [Package], found type %X\n",
314 			package->Type));
315 		status = AE_BAD_DATA;
316 		acpi_util_eval_error(handle, pathname, status);
317 		goto end;
318 	}
319 	if (!package->Package.Count) {
320 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
321 			"[Package] has zero elements (%p)\n",
322 			package));
323 		status = AE_BAD_DATA;
324 		acpi_util_eval_error(handle, pathname, status);
325 		goto end;
326 	}
327 
328 	if (package->Package.Count > ACPI_MAX_HANDLES) {
329 		return AE_NO_MEMORY;
330 	}
331 	list->count = package->Package.Count;
332 
333 	/* Extract package data. */
334 
335 	for (i = 0; i < list->count; i++) {
336 
337 		element = &(package->Package.Elements[i]);
338 
339 		if (element->Type != ACPI_TYPE_LOCAL_REFERENCE) {
340 			status = AE_BAD_DATA;
341 			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
342 				"Expecting a [Reference] package element, found type %X\n",
343 				element->type));
344 			acpi_util_eval_error(handle, pathname, status);
345 			break;
346 		}
347 
348 		if (!element->Reference.Handle) {
349 			ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid reference in"
350 			       " package %s\n", pathname));
351 			status = AE_NULL_ENTRY;
352 			break;
353 		}
354 		/* Get the  ACPI_HANDLE. */
355 
356 		list->handles[i] = element->Reference.Handle;
357 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
358 			list->handles[i]));
359 	}
360 
361 end:
362 	if (ACPI_FAILURE(status)) {
363 		list->count = 0;
364 		//ExFreePool(list->handles);
365 	}
366 
367     if (buffer.Pointer)
368         AcpiOsFree(buffer.Pointer);
369 
370 	return_ACPI_STATUS(status);
371 }
372 
373 NTSTATUS
374 acpi_create_registry_table(HANDLE ParentKeyHandle, ACPI_TABLE_HEADER *OutTable, PCWSTR KeyName)
375 {
376     OBJECT_ATTRIBUTES ObjectAttributes;
377     UNICODE_STRING HardwareKeyName, ValueName;
378     ANSI_STRING HardwareKeyNameA;
379     HANDLE KeyHandle = NULL, SubKeyHandle = NULL;
380     NTSTATUS Status;
381     char OemId[7] = { 0 }; /* exactly one byte more than ACPI_TABLE_HEADER->OemId */
382     char OemTableId[9] = { 0 }; /* exactly one byte more than ACPI_TABLE_HEADER->OemTableId */
383     WCHAR OemRevision[9] = { 0 }; /* enough to accept hex DWORD */
384 
385     C_ASSERT(sizeof(OemId) == RTL_FIELD_SIZE(ACPI_TABLE_HEADER, OemId) + 1);
386     C_ASSERT(sizeof(OemTableId) == RTL_FIELD_SIZE(ACPI_TABLE_HEADER, OemTableId) + 1);
387     /* Copy OEM data from the table */
388     RtlCopyMemory(OemId, OutTable->OemId, sizeof(OutTable->OemId));
389     RtlCopyMemory(OemTableId, OutTable->OemTableId, sizeof(OutTable->OemTableId));
390     /* Create table subkey */
391     RtlInitUnicodeString(&HardwareKeyName, KeyName);
392     InitializeObjectAttributes(&ObjectAttributes,
393                                &HardwareKeyName,
394                                OBJ_CASE_INSENSITIVE | OBJ_KERNEL_HANDLE,
395                                ParentKeyHandle,
396                                NULL);
397     Status = ZwCreateKey(&KeyHandle,
398                          KEY_WRITE,
399                          &ObjectAttributes,
400                          0,
401                          NULL,
402                          REG_OPTION_VOLATILE,
403                          NULL);
404     if (!NT_SUCCESS(Status))
405     {
406         DPRINT1("ZwCreateKey() for %ws failed (Status 0x%08lx)\n", KeyName, Status);
407         return Status;
408     }
409 
410     if (OutTable->OemRevision != 0)
411     {
412         /* We have OEM info in table, so create other OEM subkeys */
413         RtlInitAnsiString(&HardwareKeyNameA, OemId);
414         Status = RtlAnsiStringToUnicodeString(&HardwareKeyName, &HardwareKeyNameA, TRUE);
415         if (!NT_SUCCESS(Status))
416         {
417             DPRINT1("RtlAnsiStringToUnicodeString() for %s failed (Status 0x%08lx)\n", HardwareKeyNameA, Status);
418             ZwClose(KeyHandle);
419             return Status;
420         }
421 
422         InitializeObjectAttributes(&ObjectAttributes,
423                                    &HardwareKeyName,
424                                    OBJ_CASE_INSENSITIVE | OBJ_KERNEL_HANDLE,
425                                    KeyHandle,
426                                    NULL);
427         Status = ZwCreateKey(&SubKeyHandle,
428                              KEY_WRITE,
429                              &ObjectAttributes,
430                              0,
431                              NULL,
432                              REG_OPTION_VOLATILE,
433                              NULL);
434         RtlFreeUnicodeString(&HardwareKeyName);
435         ZwClose(KeyHandle);
436         if (!NT_SUCCESS(Status))
437         {
438             DPRINT1("ZwCreateKey() for %s failed (Status 0x%08lx)\n", HardwareKeyNameA, Status);
439             return Status;
440         }
441         KeyHandle = SubKeyHandle;
442 
443         RtlInitAnsiString(&HardwareKeyNameA, OemTableId);
444         Status = RtlAnsiStringToUnicodeString(&HardwareKeyName, &HardwareKeyNameA, TRUE);
445         if (!NT_SUCCESS(Status))
446         {
447             DPRINT1("RtlAnsiStringToUnicodeString() for %s failed (Status 0x%08lx)\n", HardwareKeyNameA, Status);
448             ZwClose(KeyHandle);
449             return Status;
450         }
451 
452         InitializeObjectAttributes(&ObjectAttributes,
453                                    &HardwareKeyName,
454                                    OBJ_CASE_INSENSITIVE | OBJ_KERNEL_HANDLE,
455                                    KeyHandle,
456                                    NULL);
457         Status = ZwCreateKey(&SubKeyHandle,
458                              KEY_WRITE,
459                              &ObjectAttributes,
460                              0,
461                              NULL,
462                              REG_OPTION_VOLATILE,
463                              NULL);
464         RtlFreeUnicodeString(&HardwareKeyName);
465         ZwClose(KeyHandle);
466         if (!NT_SUCCESS(Status))
467         {
468             DPRINT1("ZwCreateKey() for %s failed (Status 0x%08lx)\n", HardwareKeyNameA, Status);
469             return Status;
470         }
471         KeyHandle = SubKeyHandle;
472 
473         Status = RtlStringCbPrintfW(OemRevision,
474                                     sizeof(OemRevision),
475                                     L"%08X",
476                                     OutTable->OemRevision);
477         if (!NT_SUCCESS(Status))
478         {
479             DPRINT1("RtlStringCbPrintfW() for 0x%08lx failed (Status 0x%08lx)\n", OutTable->OemRevision, Status);
480             ZwClose(KeyHandle);
481             return Status;
482         }
483         RtlInitUnicodeString(&HardwareKeyName, OemRevision);
484 
485         InitializeObjectAttributes(&ObjectAttributes,
486                                    &HardwareKeyName,
487                                    OBJ_CASE_INSENSITIVE | OBJ_KERNEL_HANDLE,
488                                    KeyHandle,
489                                    NULL);
490         Status = ZwCreateKey(&SubKeyHandle,
491                              KEY_WRITE,
492                              &ObjectAttributes,
493                              0,
494                              NULL,
495                              REG_OPTION_VOLATILE,
496                              NULL);
497         ZwClose(KeyHandle);
498         if (!NT_SUCCESS(Status))
499         {
500             DPRINT1("ZwCreateKey() for %ws failed (Status 0x%08lx)\n", KeyName, Status);
501             return Status;
502         }
503         KeyHandle = SubKeyHandle;
504     }
505     /* Table reg value name is always '00000000' */
506     RtlInitUnicodeString(&ValueName,
507                          L"00000000");
508     Status = ZwSetValueKey(KeyHandle,
509                            &ValueName,
510                            0,
511                            REG_BINARY,
512                            OutTable,
513                            OutTable->Length);
514     ZwClose(KeyHandle);
515     if (!NT_SUCCESS(Status))
516     {
517         DPRINT1("ZwSetValueKey() failed (Status 0x%08lx)\n", Status);
518         return Status;
519     }
520 
521     return STATUS_SUCCESS;
522 }
523 
524 NTSTATUS
525 acpi_create_volatile_registry_tables(void)
526 {
527     OBJECT_ATTRIBUTES ObjectAttributes;
528     UNICODE_STRING HardwareKeyName = RTL_CONSTANT_STRING(L"\\Registry\\Machine\\HARDWARE\\ACPI");
529     HANDLE KeyHandle = NULL;
530     NTSTATUS Status;
531     ACPI_STATUS AcpiStatus;
532     ACPI_TABLE_HEADER *OutTable;
533     ACPI_PHYSICAL_ADDRESS RsdpAddress;
534     ACPI_TABLE_RSDP *Rsdp;
535     ACPI_PHYSICAL_ADDRESS Address;
536     UINT32 TableEntrySize;
537 
538     /* Create Main Hardware ACPI key*/
539     InitializeObjectAttributes(&ObjectAttributes,
540                                &HardwareKeyName,
541                                OBJ_CASE_INSENSITIVE | OBJ_KERNEL_HANDLE,
542                                NULL,
543                                NULL);
544     Status = ZwCreateKey(&KeyHandle,
545                          KEY_WRITE,
546                          &ObjectAttributes,
547                          0,
548                          NULL,
549                          REG_OPTION_VOLATILE,
550                          NULL);
551     if (!NT_SUCCESS(Status))
552     {
553         DPRINT1("ZwCreateKey() for ACPI failed (Status 0x%08lx)\n", Status);
554         return Status;
555     }
556     /* Read DSDT table */
557     AcpiStatus = AcpiGetTable(ACPI_SIG_DSDT, 0, &OutTable);
558     if (ACPI_FAILURE(AcpiStatus))
559     {
560         DPRINT1("AcpiGetTable() for DSDT failed (Status 0x%08lx)\n", AcpiStatus);
561         Status = STATUS_UNSUCCESSFUL;
562         goto done;
563     }
564     /* Dump DSDT table */
565     Status = acpi_create_registry_table(KeyHandle, OutTable, L"DSDT");
566     if (!NT_SUCCESS(Status))
567     {
568         DPRINT1("acpi_dump_table_to_registry() for DSDT failed (Status 0x%08lx)\n", Status);
569         goto done;
570     }
571     /* Read FACS table */
572     AcpiStatus = AcpiGetTable(ACPI_SIG_FACS, 0, &OutTable);
573     if (ACPI_FAILURE(AcpiStatus))
574     {
575         DPRINT1("AcpiGetTable() for FACS failed (Status 0x%08lx)\n", AcpiStatus);
576         Status = STATUS_UNSUCCESSFUL;
577         goto done;
578     }
579     /* Dump FACS table */
580     Status = acpi_create_registry_table(KeyHandle, OutTable, L"FACS");
581     if (!NT_SUCCESS(Status))
582     {
583         DPRINT1("acpi_dump_table_to_registry() for FACS failed (Status 0x%08lx)\n", Status);
584         goto done;
585     }
586     /* Read FACS table */
587     AcpiStatus = AcpiGetTable(ACPI_SIG_FADT, 0, &OutTable);
588     if (ACPI_FAILURE(AcpiStatus))
589     {
590         DPRINT1("AcpiGetTable() for FADT failed (Status 0x%08lx)\n", AcpiStatus);
591         Status = STATUS_UNSUCCESSFUL;
592         goto done;
593     }
594     /* Dump FADT table */
595     Status = acpi_create_registry_table(KeyHandle, OutTable, L"FADT");
596     if (!NT_SUCCESS(Status))
597     {
598         DPRINT1("acpi_dump_table_to_registry() for FADT failed (Status 0x%08lx)\n", Status);
599         goto done;
600     }
601     /* This is a rough copy from ACPICA reading of RSDT/XSDT and added to avoid patching acpica */
602     RsdpAddress = AcpiOsGetRootPointer();
603     /* Map the entire RSDP and extract the address of the RSDT or XSDT */
604     Rsdp = AcpiOsMapMemory(RsdpAddress, sizeof(ACPI_TABLE_RSDP));
605     if (!Rsdp)
606     {
607         DPRINT1("AcpiOsMapMemory() failed\n");
608         Status = STATUS_NO_MEMORY;
609         goto done;
610     }
611     /* Use XSDT if present and not overridden. Otherwise, use RSDT */
612     if ((Rsdp->Revision > 1) &&
613         Rsdp->XsdtPhysicalAddress &&
614         !AcpiGbl_DoNotUseXsdt)
615     {
616         /*
617         * RSDP contains an XSDT (64-bit physical addresses). We must use
618         * the XSDT if the revision is > 1 and the XSDT pointer is present,
619         * as per the ACPI specification.
620         */
621         Address = (ACPI_PHYSICAL_ADDRESS)Rsdp->XsdtPhysicalAddress;
622         TableEntrySize = ACPI_XSDT_ENTRY_SIZE;
623     }
624     else
625     {
626         /* Root table is an RSDT (32-bit physical addresses) */
627         Address = (ACPI_PHYSICAL_ADDRESS)Rsdp->RsdtPhysicalAddress;
628         TableEntrySize = ACPI_RSDT_ENTRY_SIZE;
629     }
630     /*
631     * It is not possible to map more than one entry in some environments,
632     * so unmap the RSDP here before mapping other tables
633     */
634     AcpiOsUnmapMemory(Rsdp, sizeof(ACPI_TABLE_RSDP));
635     OutTable = AcpiOsMapMemory(Address, TableEntrySize);
636     if (!OutTable)
637     {
638         DPRINT1("AcpiOsMapMemory() failed\n");
639         Status = STATUS_NO_MEMORY;
640         goto done;
641     }
642     /* Dump RSDT table */
643     Status = acpi_create_registry_table(KeyHandle, OutTable, L"RSDT");
644     AcpiOsUnmapMemory(OutTable, TableEntrySize);
645     if (!NT_SUCCESS(Status))
646     {
647         DPRINT1("acpi_dump_table_to_registry() for RSDT failed (Status 0x%08lx)\n", Status);
648     }
649 
650 done:
651     ZwClose(KeyHandle);
652     return Status;
653 }
654