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v4.10.11
 
  1/******************************************************************************
  2 *
  3 * Module Name: tbutils - ACPI Table utilities
  4 *
 
 
  5 *****************************************************************************/
  6
  7/*
  8 * Copyright (C) 2000 - 2016, Intel Corp.
  9 * All rights reserved.
 10 *
 11 * Redistribution and use in source and binary forms, with or without
 12 * modification, are permitted provided that the following conditions
 13 * are met:
 14 * 1. Redistributions of source code must retain the above copyright
 15 *    notice, this list of conditions, and the following disclaimer,
 16 *    without modification.
 17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 18 *    substantially similar to the "NO WARRANTY" disclaimer below
 19 *    ("Disclaimer") and any redistribution must be conditioned upon
 20 *    including a substantially similar Disclaimer requirement for further
 21 *    binary redistribution.
 22 * 3. Neither the names of the above-listed copyright holders nor the names
 23 *    of any contributors may be used to endorse or promote products derived
 24 *    from this software without specific prior written permission.
 25 *
 26 * Alternatively, this software may be distributed under the terms of the
 27 * GNU General Public License ("GPL") version 2 as published by the Free
 28 * Software Foundation.
 29 *
 30 * NO WARRANTY
 31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 41 * POSSIBILITY OF SUCH DAMAGES.
 42 */
 43
 44#include <acpi/acpi.h>
 45#include "accommon.h"
 46#include "actables.h"
 47
 48#define _COMPONENT          ACPI_TABLES
 49ACPI_MODULE_NAME("tbutils")
 50
 51/* Local prototypes */
 52static acpi_physical_address
 53acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size);
 54
 55#if (!ACPI_REDUCED_HARDWARE)
 56/*******************************************************************************
 57 *
 58 * FUNCTION:    acpi_tb_initialize_facs
 59 *
 60 * PARAMETERS:  None
 61 *
 62 * RETURN:      Status
 63 *
 64 * DESCRIPTION: Create a permanent mapping for the FADT and save it in a global
 65 *              for accessing the Global Lock and Firmware Waking Vector
 66 *
 67 ******************************************************************************/
 68
 69acpi_status acpi_tb_initialize_facs(void)
 70{
 71	struct acpi_table_facs *facs;
 72
 73	/* If Hardware Reduced flag is set, there is no FACS */
 74
 75	if (acpi_gbl_reduced_hardware) {
 76		acpi_gbl_FACS = NULL;
 77		return (AE_OK);
 78	} else if (acpi_gbl_FADT.Xfacs &&
 79		   (!acpi_gbl_FADT.facs
 80		    || !acpi_gbl_use32_bit_facs_addresses)) {
 81		(void)acpi_get_table_by_index(acpi_gbl_xfacs_index,
 82					      ACPI_CAST_INDIRECT_PTR(struct
 83								     acpi_table_header,
 84								     &facs));
 85		acpi_gbl_FACS = facs;
 86	} else if (acpi_gbl_FADT.facs) {
 87		(void)acpi_get_table_by_index(acpi_gbl_facs_index,
 88					      ACPI_CAST_INDIRECT_PTR(struct
 89								     acpi_table_header,
 90								     &facs));
 91		acpi_gbl_FACS = facs;
 92	}
 93
 94	/* If there is no FACS, just continue. There was already an error msg */
 95
 96	return (AE_OK);
 97}
 98#endif				/* !ACPI_REDUCED_HARDWARE */
 99
100/*******************************************************************************
101 *
102 * FUNCTION:    acpi_tb_check_dsdt_header
103 *
104 * PARAMETERS:  None
105 *
106 * RETURN:      None
107 *
108 * DESCRIPTION: Quick compare to check validity of the DSDT. This will detect
109 *              if the DSDT has been replaced from outside the OS and/or if
110 *              the DSDT header has been corrupted.
111 *
112 ******************************************************************************/
113
114void acpi_tb_check_dsdt_header(void)
115{
116
117	/* Compare original length and checksum to current values */
118
119	if (acpi_gbl_original_dsdt_header.length != acpi_gbl_DSDT->length ||
120	    acpi_gbl_original_dsdt_header.checksum != acpi_gbl_DSDT->checksum) {
121		ACPI_BIOS_ERROR((AE_INFO,
122				 "The DSDT has been corrupted or replaced - "
123				 "old, new headers below"));
124
125		acpi_tb_print_table_header(0, &acpi_gbl_original_dsdt_header);
126		acpi_tb_print_table_header(0, acpi_gbl_DSDT);
127
128		ACPI_ERROR((AE_INFO,
129			    "Please send DMI info to linux-acpi@vger.kernel.org\n"
130			    "If system does not work as expected, please boot with acpi=copy_dsdt"));
131
132		/* Disable further error messages */
133
134		acpi_gbl_original_dsdt_header.length = acpi_gbl_DSDT->length;
135		acpi_gbl_original_dsdt_header.checksum =
136		    acpi_gbl_DSDT->checksum;
137	}
138}
139
140/*******************************************************************************
141 *
142 * FUNCTION:    acpi_tb_copy_dsdt
143 *
144 * PARAMETERS:  table_desc          - Installed table to copy
145 *
146 * RETURN:      None
147 *
148 * DESCRIPTION: Implements a subsystem option to copy the DSDT to local memory.
149 *              Some very bad BIOSs are known to either corrupt the DSDT or
150 *              install a new, bad DSDT. This copy works around the problem.
151 *
152 ******************************************************************************/
153
154struct acpi_table_header *acpi_tb_copy_dsdt(u32 table_index)
155{
156	struct acpi_table_header *new_table;
157	struct acpi_table_desc *table_desc;
158
159	table_desc = &acpi_gbl_root_table_list.tables[table_index];
160
161	new_table = ACPI_ALLOCATE(table_desc->length);
162	if (!new_table) {
163		ACPI_ERROR((AE_INFO, "Could not copy DSDT of length 0x%X",
164			    table_desc->length));
165		return (NULL);
166	}
167
168	memcpy(new_table, table_desc->pointer, table_desc->length);
169	acpi_tb_uninstall_table(table_desc);
170
171	acpi_tb_init_table_descriptor(&acpi_gbl_root_table_list.
172				      tables[acpi_gbl_dsdt_index],
173				      ACPI_PTR_TO_PHYSADDR(new_table),
174				      ACPI_TABLE_ORIGIN_INTERNAL_VIRTUAL,
175				      new_table);
176
177	ACPI_INFO(("Forced DSDT copy: length 0x%05X copied locally, original unmapped", new_table->length));
178
179	return (new_table);
180}
181
182/*******************************************************************************
183 *
184 * FUNCTION:    acpi_tb_get_root_table_entry
185 *
186 * PARAMETERS:  table_entry         - Pointer to the RSDT/XSDT table entry
187 *              table_entry_size    - sizeof 32 or 64 (RSDT or XSDT)
188 *
189 * RETURN:      Physical address extracted from the root table
190 *
191 * DESCRIPTION: Get one root table entry. Handles 32-bit and 64-bit cases on
192 *              both 32-bit and 64-bit platforms
193 *
194 * NOTE:        acpi_physical_address is 32-bit on 32-bit platforms, 64-bit on
195 *              64-bit platforms.
196 *
197 ******************************************************************************/
198
199static acpi_physical_address
200acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size)
201{
 
202	u64 address64;
203
204	/*
205	 * Get the table physical address (32-bit for RSDT, 64-bit for XSDT):
206	 * Note: Addresses are 32-bit aligned (not 64) in both RSDT and XSDT
207	 */
208	if (table_entry_size == ACPI_RSDT_ENTRY_SIZE) {
209		/*
210		 * 32-bit platform, RSDT: Return 32-bit table entry
211		 * 64-bit platform, RSDT: Expand 32-bit to 64-bit and return
212		 */
213		return ((acpi_physical_address)
214			(*ACPI_CAST_PTR(u32, table_entry)));
215	} else {
216		/*
217		 * 32-bit platform, XSDT: Truncate 64-bit to 32-bit and return
218		 * 64-bit platform, XSDT: Move (unaligned) 64-bit to local,
219		 *  return 64-bit
220		 */
221		ACPI_MOVE_64_TO_64(&address64, table_entry);
222
223#if ACPI_MACHINE_WIDTH == 32
224		if (address64 > ACPI_UINT32_MAX) {
225
226			/* Will truncate 64-bit address to 32 bits, issue warning */
227
228			ACPI_BIOS_WARNING((AE_INFO,
229					   "64-bit Physical Address in XSDT is too large (0x%8.8X%8.8X),"
230					   " truncating",
231					   ACPI_FORMAT_UINT64(address64)));
232		}
233#endif
234		return ((acpi_physical_address)(address64));
235	}
236}
237
238/*******************************************************************************
239 *
240 * FUNCTION:    acpi_tb_parse_root_table
241 *
242 * PARAMETERS:  rsdp                    - Pointer to the RSDP
243 *
244 * RETURN:      Status
245 *
246 * DESCRIPTION: This function is called to parse the Root System Description
247 *              Table (RSDT or XSDT)
248 *
249 * NOTE:        Tables are mapped (not copied) for efficiency. The FACS must
250 *              be mapped and cannot be copied because it contains the actual
251 *              memory location of the ACPI Global Lock.
252 *
253 ******************************************************************************/
254
255acpi_status ACPI_INIT_FUNCTION
256acpi_tb_parse_root_table(acpi_physical_address rsdp_address)
257{
258	struct acpi_table_rsdp *rsdp;
259	u32 table_entry_size;
260	u32 i;
261	u32 table_count;
262	struct acpi_table_header *table;
263	acpi_physical_address address;
264	u32 length;
265	u8 *table_entry;
266	acpi_status status;
267	u32 table_index;
268
269	ACPI_FUNCTION_TRACE(tb_parse_root_table);
270
271	/* Map the entire RSDP and extract the address of the RSDT or XSDT */
272
273	rsdp = acpi_os_map_memory(rsdp_address, sizeof(struct acpi_table_rsdp));
274	if (!rsdp) {
275		return_ACPI_STATUS(AE_NO_MEMORY);
276	}
277
278	acpi_tb_print_table_header(rsdp_address,
279				   ACPI_CAST_PTR(struct acpi_table_header,
280						 rsdp));
281
282	/* Use XSDT if present and not overridden. Otherwise, use RSDT */
283
284	if ((rsdp->revision > 1) &&
285	    rsdp->xsdt_physical_address && !acpi_gbl_do_not_use_xsdt) {
286		/*
287		 * RSDP contains an XSDT (64-bit physical addresses). We must use
288		 * the XSDT if the revision is > 1 and the XSDT pointer is present,
289		 * as per the ACPI specification.
290		 */
291		address = (acpi_physical_address)rsdp->xsdt_physical_address;
292		table_entry_size = ACPI_XSDT_ENTRY_SIZE;
293	} else {
294		/* Root table is an RSDT (32-bit physical addresses) */
295
296		address = (acpi_physical_address)rsdp->rsdt_physical_address;
297		table_entry_size = ACPI_RSDT_ENTRY_SIZE;
298	}
299
300	/*
301	 * It is not possible to map more than one entry in some environments,
302	 * so unmap the RSDP here before mapping other tables
303	 */
304	acpi_os_unmap_memory(rsdp, sizeof(struct acpi_table_rsdp));
305
306	/* Map the RSDT/XSDT table header to get the full table length */
307
308	table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
309	if (!table) {
310		return_ACPI_STATUS(AE_NO_MEMORY);
311	}
312
313	acpi_tb_print_table_header(address, table);
314
315	/*
316	 * Validate length of the table, and map entire table.
317	 * Minimum length table must contain at least one entry.
318	 */
319	length = table->length;
320	acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
321
322	if (length < (sizeof(struct acpi_table_header) + table_entry_size)) {
323		ACPI_BIOS_ERROR((AE_INFO,
324				 "Invalid table length 0x%X in RSDT/XSDT",
325				 length));
326		return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
327	}
328
329	table = acpi_os_map_memory(address, length);
330	if (!table) {
331		return_ACPI_STATUS(AE_NO_MEMORY);
332	}
333
334	/* Validate the root table checksum */
335
336	status = acpi_tb_verify_checksum(table, length);
337	if (ACPI_FAILURE(status)) {
338		acpi_os_unmap_memory(table, length);
339		return_ACPI_STATUS(status);
340	}
341
342	/* Get the number of entries and pointer to first entry */
343
344	table_count = (u32)((table->length - sizeof(struct acpi_table_header)) /
345			    table_entry_size);
346	table_entry = ACPI_ADD_PTR(u8, table, sizeof(struct acpi_table_header));
347
348	/* Initialize the root table array from the RSDT/XSDT */
349
350	for (i = 0; i < table_count; i++) {
351
352		/* Get the table physical address (32-bit for RSDT, 64-bit for XSDT) */
353
354		address =
355		    acpi_tb_get_root_table_entry(table_entry, table_entry_size);
356
357		/* Skip NULL entries in RSDT/XSDT */
358
359		if (!address) {
360			goto next_table;
361		}
362
363		status = acpi_tb_install_standard_table(address,
364							ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL,
365							FALSE, TRUE,
366							&table_index);
367
368		if (ACPI_SUCCESS(status) &&
369		    ACPI_COMPARE_NAME(&acpi_gbl_root_table_list.
370				      tables[table_index].signature,
371				      ACPI_SIG_FADT)) {
372			acpi_gbl_fadt_index = table_index;
373			acpi_tb_parse_fadt();
374		}
375
376next_table:
377
378		table_entry += table_entry_size;
379	}
380
381	acpi_os_unmap_memory(table, length);
382	return_ACPI_STATUS(AE_OK);
383}
384
385/*******************************************************************************
386 *
387 * FUNCTION:    acpi_tb_get_table
388 *
389 * PARAMETERS:  table_desc          - Table descriptor
390 *              out_table           - Where the pointer to the table is returned
391 *
392 * RETURN:      Status and pointer to the requested table
393 *
394 * DESCRIPTION: Increase a reference to a table descriptor and return the
395 *              validated table pointer.
396 *              If the table descriptor is an entry of the root table list,
397 *              this API must be invoked with ACPI_MTX_TABLES acquired.
398 *
399 ******************************************************************************/
400
401acpi_status
402acpi_tb_get_table(struct acpi_table_desc *table_desc,
403		  struct acpi_table_header **out_table)
404{
405	acpi_status status;
406
407	ACPI_FUNCTION_TRACE(acpi_tb_get_table);
408
409	if (table_desc->validation_count == 0) {
410
411		/* Table need to be "VALIDATED" */
412
413		status = acpi_tb_validate_table(table_desc);
414		if (ACPI_FAILURE(status)) {
415			return_ACPI_STATUS(status);
416		}
417	}
418
419	table_desc->validation_count++;
420	if (table_desc->validation_count == 0) {
421		ACPI_ERROR((AE_INFO,
422			    "Table %p, Validation count is zero after increment\n",
423			    table_desc));
424		table_desc->validation_count--;
425		return_ACPI_STATUS(AE_LIMIT);
 
 
 
 
 
426	}
427
428	*out_table = table_desc->pointer;
429	return_ACPI_STATUS(AE_OK);
430}
431
432/*******************************************************************************
433 *
434 * FUNCTION:    acpi_tb_put_table
435 *
436 * PARAMETERS:  table_desc          - Table descriptor
437 *
438 * RETURN:      None
439 *
440 * DESCRIPTION: Decrease a reference to a table descriptor and release the
441 *              validated table pointer if no references.
442 *              If the table descriptor is an entry of the root table list,
443 *              this API must be invoked with ACPI_MTX_TABLES acquired.
444 *
445 ******************************************************************************/
446
447void acpi_tb_put_table(struct acpi_table_desc *table_desc)
448{
449
450	ACPI_FUNCTION_TRACE(acpi_tb_put_table);
451
452	if (table_desc->validation_count == 0) {
453		ACPI_WARNING((AE_INFO,
454			      "Table %p, Validation count is zero before decrement\n",
455			      table_desc));
456		return_VOID;
 
 
 
 
 
 
 
 
457	}
458	table_desc->validation_count--;
459
460	if (table_desc->validation_count == 0) {
461
462		/* Table need to be "INVALIDATED" */
463
464		acpi_tb_invalidate_table(table_desc);
465	}
466
467	return_VOID;
468}
v6.8
  1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
  2/******************************************************************************
  3 *
  4 * Module Name: tbutils - ACPI Table utilities
  5 *
  6 * Copyright (C) 2000 - 2023, Intel Corp.
  7 *
  8 *****************************************************************************/
  9
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 10#include <acpi/acpi.h>
 11#include "accommon.h"
 12#include "actables.h"
 13
 14#define _COMPONENT          ACPI_TABLES
 15ACPI_MODULE_NAME("tbutils")
 16
 17/* Local prototypes */
 18static acpi_physical_address
 19acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size);
 20
 21#if (!ACPI_REDUCED_HARDWARE)
 22/*******************************************************************************
 23 *
 24 * FUNCTION:    acpi_tb_initialize_facs
 25 *
 26 * PARAMETERS:  None
 27 *
 28 * RETURN:      Status
 29 *
 30 * DESCRIPTION: Create a permanent mapping for the FADT and save it in a global
 31 *              for accessing the Global Lock and Firmware Waking Vector
 32 *
 33 ******************************************************************************/
 34
 35acpi_status acpi_tb_initialize_facs(void)
 36{
 37	struct acpi_table_facs *facs;
 38
 39	/* If Hardware Reduced flag is set, there is no FACS */
 40
 41	if (acpi_gbl_reduced_hardware) {
 42		acpi_gbl_FACS = NULL;
 43		return (AE_OK);
 44	} else if (acpi_gbl_FADT.Xfacs &&
 45		   (!acpi_gbl_FADT.facs
 46		    || !acpi_gbl_use32_bit_facs_addresses)) {
 47		(void)acpi_get_table_by_index(acpi_gbl_xfacs_index,
 48					      ACPI_CAST_INDIRECT_PTR(struct
 49								     acpi_table_header,
 50								     &facs));
 51		acpi_gbl_FACS = facs;
 52	} else if (acpi_gbl_FADT.facs) {
 53		(void)acpi_get_table_by_index(acpi_gbl_facs_index,
 54					      ACPI_CAST_INDIRECT_PTR(struct
 55								     acpi_table_header,
 56								     &facs));
 57		acpi_gbl_FACS = facs;
 58	}
 59
 60	/* If there is no FACS, just continue. There was already an error msg */
 61
 62	return (AE_OK);
 63}
 64#endif				/* !ACPI_REDUCED_HARDWARE */
 65
 66/*******************************************************************************
 67 *
 68 * FUNCTION:    acpi_tb_check_dsdt_header
 69 *
 70 * PARAMETERS:  None
 71 *
 72 * RETURN:      None
 73 *
 74 * DESCRIPTION: Quick compare to check validity of the DSDT. This will detect
 75 *              if the DSDT has been replaced from outside the OS and/or if
 76 *              the DSDT header has been corrupted.
 77 *
 78 ******************************************************************************/
 79
 80void acpi_tb_check_dsdt_header(void)
 81{
 82
 83	/* Compare original length and checksum to current values */
 84
 85	if (acpi_gbl_original_dsdt_header.length != acpi_gbl_DSDT->length ||
 86	    acpi_gbl_original_dsdt_header.checksum != acpi_gbl_DSDT->checksum) {
 87		ACPI_BIOS_ERROR((AE_INFO,
 88				 "The DSDT has been corrupted or replaced - "
 89				 "old, new headers below"));
 90
 91		acpi_tb_print_table_header(0, &acpi_gbl_original_dsdt_header);
 92		acpi_tb_print_table_header(0, acpi_gbl_DSDT);
 93
 94		ACPI_ERROR((AE_INFO,
 95			    "Please send DMI info to linux-acpi@vger.kernel.org\n"
 96			    "If system does not work as expected, please boot with acpi=copy_dsdt"));
 97
 98		/* Disable further error messages */
 99
100		acpi_gbl_original_dsdt_header.length = acpi_gbl_DSDT->length;
101		acpi_gbl_original_dsdt_header.checksum =
102		    acpi_gbl_DSDT->checksum;
103	}
104}
105
106/*******************************************************************************
107 *
108 * FUNCTION:    acpi_tb_copy_dsdt
109 *
110 * PARAMETERS:  table_index         - Index of installed table to copy
111 *
112 * RETURN:      The copied DSDT
113 *
114 * DESCRIPTION: Implements a subsystem option to copy the DSDT to local memory.
115 *              Some very bad BIOSs are known to either corrupt the DSDT or
116 *              install a new, bad DSDT. This copy works around the problem.
117 *
118 ******************************************************************************/
119
120struct acpi_table_header *acpi_tb_copy_dsdt(u32 table_index)
121{
122	struct acpi_table_header *new_table;
123	struct acpi_table_desc *table_desc;
124
125	table_desc = &acpi_gbl_root_table_list.tables[table_index];
126
127	new_table = ACPI_ALLOCATE(table_desc->length);
128	if (!new_table) {
129		ACPI_ERROR((AE_INFO, "Could not copy DSDT of length 0x%X",
130			    table_desc->length));
131		return (NULL);
132	}
133
134	memcpy(new_table, table_desc->pointer, table_desc->length);
135	acpi_tb_uninstall_table(table_desc);
136
137	acpi_tb_init_table_descriptor(&acpi_gbl_root_table_list.
138				      tables[acpi_gbl_dsdt_index],
139				      ACPI_PTR_TO_PHYSADDR(new_table),
140				      ACPI_TABLE_ORIGIN_INTERNAL_VIRTUAL,
141				      new_table);
142
143	ACPI_INFO(("Forced DSDT copy: length 0x%05X copied locally, original unmapped", new_table->length));
144
145	return (new_table);
146}
147
148/*******************************************************************************
149 *
150 * FUNCTION:    acpi_tb_get_root_table_entry
151 *
152 * PARAMETERS:  table_entry         - Pointer to the RSDT/XSDT table entry
153 *              table_entry_size    - sizeof 32 or 64 (RSDT or XSDT)
154 *
155 * RETURN:      Physical address extracted from the root table
156 *
157 * DESCRIPTION: Get one root table entry. Handles 32-bit and 64-bit cases on
158 *              both 32-bit and 64-bit platforms
159 *
160 * NOTE:        acpi_physical_address is 32-bit on 32-bit platforms, 64-bit on
161 *              64-bit platforms.
162 *
163 ******************************************************************************/
164
165static acpi_physical_address
166acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size)
167{
168	u32 address32;
169	u64 address64;
170
171	/*
172	 * Get the table physical address (32-bit for RSDT, 64-bit for XSDT):
173	 * Note: Addresses are 32-bit aligned (not 64) in both RSDT and XSDT
174	 */
175	if (table_entry_size == ACPI_RSDT_ENTRY_SIZE) {
176		/*
177		 * 32-bit platform, RSDT: Return 32-bit table entry
178		 * 64-bit platform, RSDT: Expand 32-bit to 64-bit and return
179		 */
180		ACPI_MOVE_32_TO_32(&address32, table_entry);
181		return address32;
182	} else {
183		/*
184		 * 32-bit platform, XSDT: Truncate 64-bit to 32-bit and return
185		 * 64-bit platform, XSDT: Move (unaligned) 64-bit to local,
186		 *  return 64-bit
187		 */
188		ACPI_MOVE_64_TO_64(&address64, table_entry);
189
190#if ACPI_MACHINE_WIDTH == 32
191		if (address64 > ACPI_UINT32_MAX) {
192
193			/* Will truncate 64-bit address to 32 bits, issue warning */
194
195			ACPI_BIOS_WARNING((AE_INFO,
196					   "64-bit Physical Address in XSDT is too large (0x%8.8X%8.8X),"
197					   " truncating",
198					   ACPI_FORMAT_UINT64(address64)));
199		}
200#endif
201		return ((acpi_physical_address)(address64));
202	}
203}
204
205/*******************************************************************************
206 *
207 * FUNCTION:    acpi_tb_parse_root_table
208 *
209 * PARAMETERS:  rsdp_address        - Pointer to the RSDP
210 *
211 * RETURN:      Status
212 *
213 * DESCRIPTION: This function is called to parse the Root System Description
214 *              Table (RSDT or XSDT)
215 *
216 * NOTE:        Tables are mapped (not copied) for efficiency. The FACS must
217 *              be mapped and cannot be copied because it contains the actual
218 *              memory location of the ACPI Global Lock.
219 *
220 ******************************************************************************/
221
222acpi_status ACPI_INIT_FUNCTION
223acpi_tb_parse_root_table(acpi_physical_address rsdp_address)
224{
225	struct acpi_table_rsdp *rsdp;
226	u32 table_entry_size;
227	u32 i;
228	u32 table_count;
229	struct acpi_table_header *table;
230	acpi_physical_address address;
231	u32 length;
232	u8 *table_entry;
233	acpi_status status;
234	u32 table_index;
235
236	ACPI_FUNCTION_TRACE(tb_parse_root_table);
237
238	/* Map the entire RSDP and extract the address of the RSDT or XSDT */
239
240	rsdp = acpi_os_map_memory(rsdp_address, sizeof(struct acpi_table_rsdp));
241	if (!rsdp) {
242		return_ACPI_STATUS(AE_NO_MEMORY);
243	}
244
245	acpi_tb_print_table_header(rsdp_address,
246				   ACPI_CAST_PTR(struct acpi_table_header,
247						 rsdp));
248
249	/* Use XSDT if present and not overridden. Otherwise, use RSDT */
250
251	if ((rsdp->revision > 1) &&
252	    rsdp->xsdt_physical_address && !acpi_gbl_do_not_use_xsdt) {
253		/*
254		 * RSDP contains an XSDT (64-bit physical addresses). We must use
255		 * the XSDT if the revision is > 1 and the XSDT pointer is present,
256		 * as per the ACPI specification.
257		 */
258		address = (acpi_physical_address)rsdp->xsdt_physical_address;
259		table_entry_size = ACPI_XSDT_ENTRY_SIZE;
260	} else {
261		/* Root table is an RSDT (32-bit physical addresses) */
262
263		address = (acpi_physical_address)rsdp->rsdt_physical_address;
264		table_entry_size = ACPI_RSDT_ENTRY_SIZE;
265	}
266
267	/*
268	 * It is not possible to map more than one entry in some environments,
269	 * so unmap the RSDP here before mapping other tables
270	 */
271	acpi_os_unmap_memory(rsdp, sizeof(struct acpi_table_rsdp));
272
273	/* Map the RSDT/XSDT table header to get the full table length */
274
275	table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
276	if (!table) {
277		return_ACPI_STATUS(AE_NO_MEMORY);
278	}
279
280	acpi_tb_print_table_header(address, table);
281
282	/*
283	 * Validate length of the table, and map entire table.
284	 * Minimum length table must contain at least one entry.
285	 */
286	length = table->length;
287	acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
288
289	if (length < (sizeof(struct acpi_table_header) + table_entry_size)) {
290		ACPI_BIOS_ERROR((AE_INFO,
291				 "Invalid table length 0x%X in RSDT/XSDT",
292				 length));
293		return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
294	}
295
296	table = acpi_os_map_memory(address, length);
297	if (!table) {
298		return_ACPI_STATUS(AE_NO_MEMORY);
299	}
300
301	/* Validate the root table checksum */
302
303	status = acpi_ut_verify_checksum(table, length);
304	if (ACPI_FAILURE(status)) {
305		acpi_os_unmap_memory(table, length);
306		return_ACPI_STATUS(status);
307	}
308
309	/* Get the number of entries and pointer to first entry */
310
311	table_count = (u32)((table->length - sizeof(struct acpi_table_header)) /
312			    table_entry_size);
313	table_entry = ACPI_ADD_PTR(u8, table, sizeof(struct acpi_table_header));
314
315	/* Initialize the root table array from the RSDT/XSDT */
316
317	for (i = 0; i < table_count; i++) {
318
319		/* Get the table physical address (32-bit for RSDT, 64-bit for XSDT) */
320
321		address =
322		    acpi_tb_get_root_table_entry(table_entry, table_entry_size);
323
324		/* Skip NULL entries in RSDT/XSDT */
325
326		if (!address) {
327			goto next_table;
328		}
329
330		status = acpi_tb_install_standard_table(address,
331							ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL,
332							NULL, FALSE, TRUE,
333							&table_index);
334
335		if (ACPI_SUCCESS(status) &&
336		    ACPI_COMPARE_NAMESEG(&acpi_gbl_root_table_list.
337					 tables[table_index].signature,
338					 ACPI_SIG_FADT)) {
339			acpi_gbl_fadt_index = table_index;
340			acpi_tb_parse_fadt();
341		}
342
343next_table:
344
345		table_entry += table_entry_size;
346	}
347
348	acpi_os_unmap_memory(table, length);
349	return_ACPI_STATUS(AE_OK);
350}
351
352/*******************************************************************************
353 *
354 * FUNCTION:    acpi_tb_get_table
355 *
356 * PARAMETERS:  table_desc          - Table descriptor
357 *              out_table           - Where the pointer to the table is returned
358 *
359 * RETURN:      Status and pointer to the requested table
360 *
361 * DESCRIPTION: Increase a reference to a table descriptor and return the
362 *              validated table pointer.
363 *              If the table descriptor is an entry of the root table list,
364 *              this API must be invoked with ACPI_MTX_TABLES acquired.
365 *
366 ******************************************************************************/
367
368acpi_status
369acpi_tb_get_table(struct acpi_table_desc *table_desc,
370		  struct acpi_table_header **out_table)
371{
372	acpi_status status;
373
374	ACPI_FUNCTION_TRACE(acpi_tb_get_table);
375
376	if (table_desc->validation_count == 0) {
377
378		/* Table need to be "VALIDATED" */
379
380		status = acpi_tb_validate_table(table_desc);
381		if (ACPI_FAILURE(status)) {
382			return_ACPI_STATUS(status);
383		}
384	}
385
386	if (table_desc->validation_count < ACPI_MAX_TABLE_VALIDATIONS) {
387		table_desc->validation_count++;
388
389		/*
390		 * Detect validation_count overflows to ensure that the warning
391		 * message will only be printed once.
392		 */
393		if (table_desc->validation_count >= ACPI_MAX_TABLE_VALIDATIONS) {
394			ACPI_WARNING((AE_INFO,
395				      "Table %p, Validation count overflows\n",
396				      table_desc));
397		}
398	}
399
400	*out_table = table_desc->pointer;
401	return_ACPI_STATUS(AE_OK);
402}
403
404/*******************************************************************************
405 *
406 * FUNCTION:    acpi_tb_put_table
407 *
408 * PARAMETERS:  table_desc          - Table descriptor
409 *
410 * RETURN:      None
411 *
412 * DESCRIPTION: Decrease a reference to a table descriptor and release the
413 *              validated table pointer if no references.
414 *              If the table descriptor is an entry of the root table list,
415 *              this API must be invoked with ACPI_MTX_TABLES acquired.
416 *
417 ******************************************************************************/
418
419void acpi_tb_put_table(struct acpi_table_desc *table_desc)
420{
421
422	ACPI_FUNCTION_TRACE(acpi_tb_put_table);
423
424	if (table_desc->validation_count < ACPI_MAX_TABLE_VALIDATIONS) {
425		table_desc->validation_count--;
426
427		/*
428		 * Detect validation_count underflows to ensure that the warning
429		 * message will only be printed once.
430		 */
431		if (table_desc->validation_count >= ACPI_MAX_TABLE_VALIDATIONS) {
432			ACPI_WARNING((AE_INFO,
433				      "Table %p, Validation count underflows\n",
434				      table_desc));
435			return_VOID;
436		}
437	}
 
438
439	if (table_desc->validation_count == 0) {
440
441		/* Table need to be "INVALIDATED" */
442
443		acpi_tb_invalidate_table(table_desc);
444	}
445
446	return_VOID;
447}