xref: /openbmc/linux/drivers/acpi/acpica/tbutils.c (revision ecba1060)
1 /******************************************************************************
2  *
3  * Module Name: tbutils   - table utilities
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2008, 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
49 ACPI_MODULE_NAME("tbutils")
50 
51 /* Local prototypes */
52 static acpi_physical_address
53 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size);
54 
55 /*******************************************************************************
56  *
57  * FUNCTION:    acpi_tb_check_xsdt
58  *
59  * PARAMETERS:  address                    - Pointer to the XSDT
60  *
61  * RETURN:      status
62  *		AE_OK - XSDT is okay
63  *		AE_NO_MEMORY - can't map XSDT
64  *		AE_INVALID_TABLE_LENGTH - invalid table length
65  *		AE_NULL_ENTRY - XSDT has NULL entry
66  *
67  * DESCRIPTION: validate XSDT
68 ******************************************************************************/
69 
70 static acpi_status
71 acpi_tb_check_xsdt(acpi_physical_address address)
72 {
73 	struct acpi_table_header *table;
74 	u32 length;
75 	u64 xsdt_entry_address;
76 	u8 *table_entry;
77 	u32 table_count;
78 	int i;
79 
80 	table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
81 	if (!table)
82 		return AE_NO_MEMORY;
83 
84 	length = table->length;
85 	acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
86 	if (length < sizeof(struct acpi_table_header))
87 		return AE_INVALID_TABLE_LENGTH;
88 
89 	table = acpi_os_map_memory(address, length);
90 	if (!table)
91 		return AE_NO_MEMORY;
92 
93 	/* Calculate the number of tables described in XSDT */
94 	table_count =
95 		(u32) ((table->length -
96 		sizeof(struct acpi_table_header)) / sizeof(u64));
97 	table_entry =
98 		ACPI_CAST_PTR(u8, table) + sizeof(struct acpi_table_header);
99 	for (i = 0; i < table_count; i++) {
100 		ACPI_MOVE_64_TO_64(&xsdt_entry_address, table_entry);
101 		if (!xsdt_entry_address) {
102 			/* XSDT has NULL entry */
103 			break;
104 		}
105 		table_entry += sizeof(u64);
106 	}
107 	acpi_os_unmap_memory(table, length);
108 
109 	if (i < table_count)
110 		return AE_NULL_ENTRY;
111 	else
112 		return AE_OK;
113 }
114 
115 /*******************************************************************************
116  *
117  * FUNCTION:    acpi_tb_initialize_facs
118  *
119  * PARAMETERS:  None
120  *
121  * RETURN:      Status
122  *
123  * DESCRIPTION: Create a permanent mapping for the FADT and save it in a global
124  *              for accessing the Global Lock and Firmware Waking Vector
125  *
126  ******************************************************************************/
127 
128 acpi_status acpi_tb_initialize_facs(void)
129 {
130 	acpi_status status;
131 
132 	status = acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
133 					 ACPI_CAST_INDIRECT_PTR(struct
134 								acpi_table_header,
135 								&acpi_gbl_FACS));
136 	return status;
137 }
138 
139 /*******************************************************************************
140  *
141  * FUNCTION:    acpi_tb_tables_loaded
142  *
143  * PARAMETERS:  None
144  *
145  * RETURN:      TRUE if required ACPI tables are loaded
146  *
147  * DESCRIPTION: Determine if the minimum required ACPI tables are present
148  *              (FADT, FACS, DSDT)
149  *
150  ******************************************************************************/
151 
152 u8 acpi_tb_tables_loaded(void)
153 {
154 
155 	if (acpi_gbl_root_table_list.count >= 3) {
156 		return (TRUE);
157 	}
158 
159 	return (FALSE);
160 }
161 
162 /*******************************************************************************
163  *
164  * FUNCTION:    acpi_tb_print_table_header
165  *
166  * PARAMETERS:  Address             - Table physical address
167  *              Header              - Table header
168  *
169  * RETURN:      None
170  *
171  * DESCRIPTION: Print an ACPI table header. Special cases for FACS and RSDP.
172  *
173  ******************************************************************************/
174 
175 void
176 acpi_tb_print_table_header(acpi_physical_address address,
177 			   struct acpi_table_header *header)
178 {
179 
180 	/*
181 	 * The reason that the Address is cast to a void pointer is so that we
182 	 * can use %p which will work properly on both 32-bit and 64-bit hosts.
183 	 */
184 	if (ACPI_COMPARE_NAME(header->signature, ACPI_SIG_FACS)) {
185 
186 		/* FACS only has signature and length fields */
187 
188 		ACPI_INFO((AE_INFO, "%4.4s %p %05X",
189 			   header->signature, ACPI_CAST_PTR(void, address),
190 			   header->length));
191 	} else if (ACPI_COMPARE_NAME(header->signature, ACPI_SIG_RSDP)) {
192 
193 		/* RSDP has no common fields */
194 
195 		ACPI_INFO((AE_INFO, "RSDP %p %05X (v%.2d %6.6s)",
196 			   ACPI_CAST_PTR (void, address),
197 			   (ACPI_CAST_PTR(struct acpi_table_rsdp, header)->
198 			    revision >
199 			    0) ? ACPI_CAST_PTR(struct acpi_table_rsdp,
200 					       header)->length : 20,
201 			   ACPI_CAST_PTR(struct acpi_table_rsdp,
202 					 header)->revision,
203 			   ACPI_CAST_PTR(struct acpi_table_rsdp,
204 					 header)->oem_id));
205 	} else {
206 		/* Standard ACPI table with full common header */
207 
208 		ACPI_INFO((AE_INFO,
209 			   "%4.4s %p %05X (v%.2d %6.6s %8.8s %08X %4.4s %08X)",
210 			   header->signature, ACPI_CAST_PTR (void, address),
211 			   header->length, header->revision, header->oem_id,
212 			   header->oem_table_id, header->oem_revision,
213 			   header->asl_compiler_id,
214 			   header->asl_compiler_revision));
215 	}
216 }
217 
218 /*******************************************************************************
219  *
220  * FUNCTION:    acpi_tb_validate_checksum
221  *
222  * PARAMETERS:  Table               - ACPI table to verify
223  *              Length              - Length of entire table
224  *
225  * RETURN:      Status
226  *
227  * DESCRIPTION: Verifies that the table checksums to zero. Optionally returns
228  *              exception on bad checksum.
229  *
230  ******************************************************************************/
231 
232 acpi_status acpi_tb_verify_checksum(struct acpi_table_header *table, u32 length)
233 {
234 	u8 checksum;
235 
236 	/* Compute the checksum on the table */
237 
238 	checksum = acpi_tb_checksum(ACPI_CAST_PTR(u8, table), length);
239 
240 	/* Checksum ok? (should be zero) */
241 
242 	if (checksum) {
243 		ACPI_WARNING((AE_INFO,
244 			      "Incorrect checksum in table [%4.4s] - %2.2X, should be %2.2X",
245 			      table->signature, table->checksum,
246 			      (u8) (table->checksum - checksum)));
247 
248 #if (ACPI_CHECKSUM_ABORT)
249 
250 		return (AE_BAD_CHECKSUM);
251 #endif
252 	}
253 
254 	return (AE_OK);
255 }
256 
257 /*******************************************************************************
258  *
259  * FUNCTION:    acpi_tb_checksum
260  *
261  * PARAMETERS:  Buffer          - Pointer to memory region to be checked
262  *              Length          - Length of this memory region
263  *
264  * RETURN:      Checksum (u8)
265  *
266  * DESCRIPTION: Calculates circular checksum of memory region.
267  *
268  ******************************************************************************/
269 
270 u8 acpi_tb_checksum(u8 *buffer, u32 length)
271 {
272 	u8 sum = 0;
273 	u8 *end = buffer + length;
274 
275 	while (buffer < end) {
276 		sum = (u8) (sum + *(buffer++));
277 	}
278 
279 	return sum;
280 }
281 
282 /*******************************************************************************
283  *
284  * FUNCTION:    acpi_tb_install_table
285  *
286  * PARAMETERS:  Address                 - Physical address of DSDT or FACS
287  *              Signature               - Table signature, NULL if no need to
288  *                                        match
289  *              table_index             - Index into root table array
290  *
291  * RETURN:      None
292  *
293  * DESCRIPTION: Install an ACPI table into the global data structure. The
294  *              table override mechanism is implemented here to allow the host
295  *              OS to replace any table before it is installed in the root
296  *              table array.
297  *
298  ******************************************************************************/
299 
300 void
301 acpi_tb_install_table(acpi_physical_address address,
302 		      char *signature, u32 table_index)
303 {
304 	u8 flags;
305 	acpi_status status;
306 	struct acpi_table_header *table_to_install;
307 	struct acpi_table_header *mapped_table;
308 	struct acpi_table_header *override_table = NULL;
309 
310 	if (!address) {
311 		ACPI_ERROR((AE_INFO,
312 			    "Null physical address for ACPI table [%s]",
313 			    signature));
314 		return;
315 	}
316 
317 	/* Map just the table header */
318 
319 	mapped_table =
320 	    acpi_os_map_memory(address, sizeof(struct acpi_table_header));
321 	if (!mapped_table) {
322 		return;
323 	}
324 
325 	/* If a particular signature is expected (DSDT/FACS), it must match */
326 
327 	if (signature && !ACPI_COMPARE_NAME(mapped_table->signature, signature)) {
328 		ACPI_ERROR((AE_INFO,
329 			    "Invalid signature 0x%X for ACPI table, expected [%s]",
330 			    *ACPI_CAST_PTR(u32, mapped_table->signature),
331 			    signature));
332 		goto unmap_and_exit;
333 	}
334 
335 	/*
336 	 * ACPI Table Override:
337 	 *
338 	 * Before we install the table, let the host OS override it with a new
339 	 * one if desired. Any table within the RSDT/XSDT can be replaced,
340 	 * including the DSDT which is pointed to by the FADT.
341 	 */
342 	status = acpi_os_table_override(mapped_table, &override_table);
343 	if (ACPI_SUCCESS(status) && override_table) {
344 		ACPI_INFO((AE_INFO,
345 			   "%4.4s @ 0x%p Table override, replaced with:",
346 			   mapped_table->signature, ACPI_CAST_PTR(void,
347 								  address)));
348 
349 		acpi_gbl_root_table_list.tables[table_index].pointer =
350 		    override_table;
351 		address = ACPI_PTR_TO_PHYSADDR(override_table);
352 
353 		table_to_install = override_table;
354 		flags = ACPI_TABLE_ORIGIN_OVERRIDE;
355 	} else {
356 		table_to_install = mapped_table;
357 		flags = ACPI_TABLE_ORIGIN_MAPPED;
358 	}
359 
360 	/* Initialize the table entry */
361 
362 	acpi_gbl_root_table_list.tables[table_index].address = address;
363 	acpi_gbl_root_table_list.tables[table_index].length =
364 	    table_to_install->length;
365 	acpi_gbl_root_table_list.tables[table_index].flags = flags;
366 
367 	ACPI_MOVE_32_TO_32(&
368 			   (acpi_gbl_root_table_list.tables[table_index].
369 			    signature), table_to_install->signature);
370 
371 	acpi_tb_print_table_header(address, table_to_install);
372 
373 	if (table_index == ACPI_TABLE_INDEX_DSDT) {
374 
375 		/* Global integer width is based upon revision of the DSDT */
376 
377 		acpi_ut_set_integer_width(table_to_install->revision);
378 	}
379 
380       unmap_and_exit:
381 	acpi_os_unmap_memory(mapped_table, sizeof(struct acpi_table_header));
382 }
383 
384 /*******************************************************************************
385  *
386  * FUNCTION:    acpi_tb_get_root_table_entry
387  *
388  * PARAMETERS:  table_entry         - Pointer to the RSDT/XSDT table entry
389  *              table_entry_size    - sizeof 32 or 64 (RSDT or XSDT)
390  *
391  * RETURN:      Physical address extracted from the root table
392  *
393  * DESCRIPTION: Get one root table entry. Handles 32-bit and 64-bit cases on
394  *              both 32-bit and 64-bit platforms
395  *
396  * NOTE:        acpi_physical_address is 32-bit on 32-bit platforms, 64-bit on
397  *              64-bit platforms.
398  *
399  ******************************************************************************/
400 
401 static acpi_physical_address
402 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size)
403 {
404 	u64 address64;
405 
406 	/*
407 	 * Get the table physical address (32-bit for RSDT, 64-bit for XSDT):
408 	 * Note: Addresses are 32-bit aligned (not 64) in both RSDT and XSDT
409 	 */
410 	if (table_entry_size == sizeof(u32)) {
411 		/*
412 		 * 32-bit platform, RSDT: Return 32-bit table entry
413 		 * 64-bit platform, RSDT: Expand 32-bit to 64-bit and return
414 		 */
415 		return ((acpi_physical_address)
416 			(*ACPI_CAST_PTR(u32, table_entry)));
417 	} else {
418 		/*
419 		 * 32-bit platform, XSDT: Truncate 64-bit to 32-bit and return
420 		 * 64-bit platform, XSDT: Move (unaligned) 64-bit to local,
421 		 *  return 64-bit
422 		 */
423 		ACPI_MOVE_64_TO_64(&address64, table_entry);
424 
425 #if ACPI_MACHINE_WIDTH == 32
426 		if (address64 > ACPI_UINT32_MAX) {
427 
428 			/* Will truncate 64-bit address to 32 bits, issue warning */
429 
430 			ACPI_WARNING((AE_INFO,
431 				      "64-bit Physical Address in XSDT is too large (%8.8X%8.8X),"
432 				      " truncating",
433 				      ACPI_FORMAT_UINT64(address64)));
434 		}
435 #endif
436 		return ((acpi_physical_address) (address64));
437 	}
438 }
439 
440 /*******************************************************************************
441  *
442  * FUNCTION:    acpi_tb_parse_root_table
443  *
444  * PARAMETERS:  Rsdp                    - Pointer to the RSDP
445  *
446  * RETURN:      Status
447  *
448  * DESCRIPTION: This function is called to parse the Root System Description
449  *              Table (RSDT or XSDT)
450  *
451  * NOTE:        Tables are mapped (not copied) for efficiency. The FACS must
452  *              be mapped and cannot be copied because it contains the actual
453  *              memory location of the ACPI Global Lock.
454  *
455  ******************************************************************************/
456 
457 acpi_status __init
458 acpi_tb_parse_root_table(acpi_physical_address rsdp_address)
459 {
460 	struct acpi_table_rsdp *rsdp;
461 	u32 table_entry_size;
462 	u32 i;
463 	u32 table_count;
464 	struct acpi_table_header *table;
465 	acpi_physical_address address;
466 	acpi_physical_address uninitialized_var(rsdt_address);
467 	u32 length;
468 	u8 *table_entry;
469 	acpi_status status;
470 
471 	ACPI_FUNCTION_TRACE(tb_parse_root_table);
472 
473 	/*
474 	 * Map the entire RSDP and extract the address of the RSDT or XSDT
475 	 */
476 	rsdp = acpi_os_map_memory(rsdp_address, sizeof(struct acpi_table_rsdp));
477 	if (!rsdp) {
478 		return_ACPI_STATUS(AE_NO_MEMORY);
479 	}
480 
481 	acpi_tb_print_table_header(rsdp_address,
482 				   ACPI_CAST_PTR(struct acpi_table_header,
483 						 rsdp));
484 
485 	/* Differentiate between RSDT and XSDT root tables */
486 
487 	if (rsdp->revision > 1 && rsdp->xsdt_physical_address
488 			&& !acpi_rsdt_forced) {
489 		/*
490 		 * Root table is an XSDT (64-bit physical addresses). We must use the
491 		 * XSDT if the revision is > 1 and the XSDT pointer is present, as per
492 		 * the ACPI specification.
493 		 */
494 		address = (acpi_physical_address) rsdp->xsdt_physical_address;
495 		table_entry_size = sizeof(u64);
496 		rsdt_address = (acpi_physical_address)
497 					rsdp->rsdt_physical_address;
498 	} else {
499 		/* Root table is an RSDT (32-bit physical addresses) */
500 
501 		address = (acpi_physical_address) rsdp->rsdt_physical_address;
502 		table_entry_size = sizeof(u32);
503 	}
504 
505 	/*
506 	 * It is not possible to map more than one entry in some environments,
507 	 * so unmap the RSDP here before mapping other tables
508 	 */
509 	acpi_os_unmap_memory(rsdp, sizeof(struct acpi_table_rsdp));
510 
511 	if (table_entry_size == sizeof(u64)) {
512 		if (acpi_tb_check_xsdt(address) == AE_NULL_ENTRY) {
513 			/* XSDT has NULL entry, RSDT is used */
514 			address = rsdt_address;
515 			table_entry_size = sizeof(u32);
516 			ACPI_WARNING((AE_INFO, "BIOS XSDT has NULL entry, "
517 					"using RSDT"));
518 		}
519 	}
520 	/* Map the RSDT/XSDT table header to get the full table length */
521 
522 	table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
523 	if (!table) {
524 		return_ACPI_STATUS(AE_NO_MEMORY);
525 	}
526 
527 	acpi_tb_print_table_header(address, table);
528 
529 	/* Get the length of the full table, verify length and map entire table */
530 
531 	length = table->length;
532 	acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
533 
534 	if (length < sizeof(struct acpi_table_header)) {
535 		ACPI_ERROR((AE_INFO, "Invalid length 0x%X in RSDT/XSDT",
536 			    length));
537 		return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
538 	}
539 
540 	table = acpi_os_map_memory(address, length);
541 	if (!table) {
542 		return_ACPI_STATUS(AE_NO_MEMORY);
543 	}
544 
545 	/* Validate the root table checksum */
546 
547 	status = acpi_tb_verify_checksum(table, length);
548 	if (ACPI_FAILURE(status)) {
549 		acpi_os_unmap_memory(table, length);
550 		return_ACPI_STATUS(status);
551 	}
552 
553 	/* Calculate the number of tables described in the root table */
554 
555 	table_count = (u32)((table->length - sizeof(struct acpi_table_header)) /
556 			    table_entry_size);
557 	/*
558 	 * First two entries in the table array are reserved for the DSDT
559 	 * and FACS, which are not actually present in the RSDT/XSDT - they
560 	 * come from the FADT
561 	 */
562 	table_entry =
563 	    ACPI_CAST_PTR(u8, table) + sizeof(struct acpi_table_header);
564 	acpi_gbl_root_table_list.count = 2;
565 
566 	/*
567 	 * Initialize the root table array from the RSDT/XSDT
568 	 */
569 	for (i = 0; i < table_count; i++) {
570 		if (acpi_gbl_root_table_list.count >=
571 		    acpi_gbl_root_table_list.size) {
572 
573 			/* There is no more room in the root table array, attempt resize */
574 
575 			status = acpi_tb_resize_root_table_list();
576 			if (ACPI_FAILURE(status)) {
577 				ACPI_WARNING((AE_INFO,
578 					      "Truncating %u table entries!",
579 					      (unsigned) (table_count -
580 					       (acpi_gbl_root_table_list.
581 					       count - 2))));
582 				break;
583 			}
584 		}
585 
586 		/* Get the table physical address (32-bit for RSDT, 64-bit for XSDT) */
587 
588 		acpi_gbl_root_table_list.tables[acpi_gbl_root_table_list.count].
589 		    address =
590 		    acpi_tb_get_root_table_entry(table_entry, table_entry_size);
591 
592 		table_entry += table_entry_size;
593 		acpi_gbl_root_table_list.count++;
594 	}
595 
596 	/*
597 	 * It is not possible to map more than one entry in some environments,
598 	 * so unmap the root table here before mapping other tables
599 	 */
600 	acpi_os_unmap_memory(table, length);
601 
602 	/*
603 	 * Complete the initialization of the root table array by examining
604 	 * the header of each table
605 	 */
606 	for (i = 2; i < acpi_gbl_root_table_list.count; i++) {
607 		acpi_tb_install_table(acpi_gbl_root_table_list.tables[i].
608 				      address, NULL, i);
609 
610 		/* Special case for FADT - get the DSDT and FACS */
611 
612 		if (ACPI_COMPARE_NAME
613 		    (&acpi_gbl_root_table_list.tables[i].signature,
614 		     ACPI_SIG_FADT)) {
615 			acpi_tb_parse_fadt(i);
616 		}
617 	}
618 
619 	return_ACPI_STATUS(AE_OK);
620 }
621