1 /******************************************************************************
2  *
3  * Module Name: tbxfroot - Find the root ACPI table (RSDT)
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2004, R. Byron Moore
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 
45 #include <acpi/acpi.h>
46 #include <acpi/actables.h>
47 
48 
49 #define _COMPONENT          ACPI_TABLES
50 	 ACPI_MODULE_NAME    ("tbxfroot")
51 
52 
53 /*******************************************************************************
54  *
55  * FUNCTION:    acpi_tb_find_table
56  *
57  * PARAMETERS:  Signature           - String with ACPI table signature
58  *              oem_id              - String with the table OEM ID
59  *              oem_table_id        - String with the OEM Table ID.
60  *
61  * RETURN:      Status
62  *
63  * DESCRIPTION: Find an ACPI table (in the RSDT/XSDT) that matches the
64  *              Signature, OEM ID and OEM Table ID.
65  *
66  ******************************************************************************/
67 
68 acpi_status
acpi_tb_find_table(char * signature,char * oem_id,char * oem_table_id,struct acpi_table_header ** table_ptr)69 acpi_tb_find_table (
70 	char                            *signature,
71 	char                            *oem_id,
72 	char                            *oem_table_id,
73 	struct acpi_table_header        **table_ptr)
74 {
75 	acpi_status                     status;
76 	struct acpi_table_header        *table;
77 
78 
79 	ACPI_FUNCTION_TRACE ("tb_find_table");
80 
81 
82 	/* Validate string lengths */
83 
84 	if ((ACPI_STRLEN (signature)  > ACPI_NAME_SIZE) ||
85 		(ACPI_STRLEN (oem_id)     > sizeof (table->oem_id)) ||
86 		(ACPI_STRLEN (oem_table_id) > sizeof (table->oem_table_id))) {
87 		return_ACPI_STATUS (AE_AML_STRING_LIMIT);
88 	}
89 
90 	/* Find the table */
91 
92 	status = acpi_get_firmware_table (signature, 1,
93 			   ACPI_LOGICAL_ADDRESSING, &table);
94 	if (ACPI_FAILURE (status)) {
95 		return_ACPI_STATUS (status);
96 	}
97 
98 	/* Check oem_id and oem_table_id */
99 
100 	if ((oem_id[0]     && ACPI_STRCMP (oem_id, table->oem_id)) ||
101 		(oem_table_id[0] && ACPI_STRCMP (oem_table_id, table->oem_table_id))) {
102 		return_ACPI_STATUS (AE_AML_NAME_NOT_FOUND);
103 	}
104 
105 	*table_ptr = table;
106 	return_ACPI_STATUS (AE_OK);
107 }
108 
109 
110 /*******************************************************************************
111  *
112  * FUNCTION:    acpi_get_firmware_table
113  *
114  * PARAMETERS:  Signature       - Any ACPI table signature
115  *              Instance        - the non zero instance of the table, allows
116  *                                support for multiple tables of the same type
117  *              Flags           - Physical/Virtual support
118  *              ret_buffer      - pointer to a structure containing a buffer to
119  *                                receive the table
120  *
121  * RETURN:      Status
122  *
123  * DESCRIPTION: This function is called to get an ACPI table.  The caller
124  *              supplies an out_buffer large enough to contain the entire ACPI
125  *              table.  Upon completion
126  *              the out_buffer->Length field will indicate the number of bytes
127  *              copied into the out_buffer->buf_ptr buffer. This table will be
128  *              a complete table including the header.
129  *
130  ******************************************************************************/
131 
132 acpi_status
acpi_get_firmware_table(acpi_string signature,u32 instance,u32 flags,struct acpi_table_header ** table_pointer)133 acpi_get_firmware_table (
134 	acpi_string                     signature,
135 	u32                             instance,
136 	u32                             flags,
137 	struct acpi_table_header        **table_pointer)
138 {
139 	struct acpi_pointer             rsdp_address;
140 	struct acpi_pointer             address;
141 	acpi_status                     status;
142 	struct acpi_table_header        header;
143 	struct acpi_table_desc          table_info;
144 	struct acpi_table_desc          rsdt_info;
145 	u32                             table_count;
146 	u32                             i;
147 	u32                             j;
148 
149 
150 	ACPI_FUNCTION_TRACE ("acpi_get_firmware_table");
151 
152 
153 	/*
154 	 * Ensure that at least the table manager is initialized.  We don't
155 	 * require that the entire ACPI subsystem is up for this interface
156 	 */
157 
158 	/*
159 	 *  If we have a buffer, we must have a length too
160 	 */
161 	if ((instance == 0)                 ||
162 		(!signature)                    ||
163 		(!table_pointer)) {
164 		return_ACPI_STATUS (AE_BAD_PARAMETER);
165 	}
166 
167 	rsdt_info.pointer = NULL;
168 
169 	if (!acpi_gbl_RSDP) {
170 		/* Get the RSDP */
171 
172 		status = acpi_os_get_root_pointer (flags, &rsdp_address);
173 		if (ACPI_FAILURE (status)) {
174 			ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "RSDP  not found\n"));
175 			return_ACPI_STATUS (AE_NO_ACPI_TABLES);
176 		}
177 
178 		/* Map and validate the RSDP */
179 
180 		if ((flags & ACPI_MEMORY_MODE) == ACPI_LOGICAL_ADDRESSING) {
181 			status = acpi_os_map_memory (rsdp_address.pointer.physical, sizeof (struct rsdp_descriptor),
182 					  (void *) &acpi_gbl_RSDP);
183 			if (ACPI_FAILURE (status)) {
184 				return_ACPI_STATUS (status);
185 			}
186 		}
187 		else {
188 			acpi_gbl_RSDP = rsdp_address.pointer.logical;
189 		}
190 
191 		/*
192 		 *  The signature and checksum must both be correct
193 		 */
194 		if (ACPI_STRNCMP ((char *) acpi_gbl_RSDP, RSDP_SIG, sizeof (RSDP_SIG)-1) != 0) {
195 			/* Nope, BAD Signature */
196 
197 			return_ACPI_STATUS (AE_BAD_SIGNATURE);
198 		}
199 
200 		if (acpi_tb_checksum (acpi_gbl_RSDP, ACPI_RSDP_CHECKSUM_LENGTH) != 0) {
201 			/* Nope, BAD Checksum */
202 
203 			return_ACPI_STATUS (AE_BAD_CHECKSUM);
204 		}
205 	}
206 
207 	/* Get the RSDT and validate it */
208 
209 	acpi_tb_get_rsdt_address (&address);
210 
211 	ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
212 		"RSDP located at %p, RSDT physical=%8.8X%8.8X \n",
213 		acpi_gbl_RSDP,
214 		ACPI_FORMAT_UINT64 (address.pointer.value)));
215 
216 	/* Insert processor_mode flags */
217 
218 	address.pointer_type |= flags;
219 
220 	status = acpi_tb_get_table (&address, &rsdt_info);
221 	if (ACPI_FAILURE (status)) {
222 		return_ACPI_STATUS (status);
223 	}
224 
225 	status = acpi_tb_validate_rsdt (rsdt_info.pointer);
226 	if (ACPI_FAILURE (status)) {
227 		goto cleanup;
228 	}
229 
230 	/* Get the number of table pointers within the RSDT */
231 
232 	table_count = acpi_tb_get_table_count (acpi_gbl_RSDP, rsdt_info.pointer);
233 
234 	address.pointer_type = acpi_gbl_table_flags | flags;
235 
236 	/*
237 	 * Search the RSDT/XSDT for the correct instance of the
238 	 * requested table
239 	 */
240 	for (i = 0, j = 0; i < table_count; i++) {
241 		/* Get the next table pointer, handle RSDT vs. XSDT */
242 
243 		if (acpi_gbl_RSDP->revision < 2) {
244 			address.pointer.value = (ACPI_CAST_PTR (RSDT_DESCRIPTOR, rsdt_info.pointer))->table_offset_entry[i];
245 		}
246 		else {
247 			address.pointer.value =
248 				(ACPI_CAST_PTR (XSDT_DESCRIPTOR, rsdt_info.pointer))->table_offset_entry[i];
249 		}
250 
251 		/* Get the table header */
252 
253 		status = acpi_tb_get_table_header (&address, &header);
254 		if (ACPI_FAILURE (status)) {
255 			goto cleanup;
256 		}
257 
258 		/* Compare table signatures and table instance */
259 
260 		if (!ACPI_STRNCMP (header.signature, signature, ACPI_NAME_SIZE)) {
261 			/* An instance of the table was found */
262 
263 			j++;
264 			if (j >= instance) {
265 				/* Found the correct instance, get the entire table */
266 
267 				status = acpi_tb_get_table_body (&address, &header, &table_info);
268 				if (ACPI_FAILURE (status)) {
269 					goto cleanup;
270 				}
271 
272 				*table_pointer = table_info.pointer;
273 				goto cleanup;
274 			}
275 		}
276 	}
277 
278 	/* Did not find the table */
279 
280 	status = AE_NOT_EXIST;
281 
282 
283 cleanup:
284 	acpi_os_unmap_memory (rsdt_info.pointer, (acpi_size) rsdt_info.pointer->length);
285 	return_ACPI_STATUS (status);
286 }
287 
288 
289 /* TBD: Move to a new file */
290 
291 #if ACPI_MACHINE_WIDTH != 16
292 
293 /*******************************************************************************
294  *
295  * FUNCTION:    acpi_find_root_pointer
296  *
297  * PARAMETERS:  **rsdp_address          - Where to place the RSDP address
298  *              Flags                   - Logical/Physical addressing
299  *
300  * RETURN:      Status, Physical address of the RSDP
301  *
302  * DESCRIPTION: Find the RSDP
303  *
304  ******************************************************************************/
305 
306 acpi_status
acpi_find_root_pointer(u32 flags,struct acpi_pointer * rsdp_address)307 acpi_find_root_pointer (
308 	u32                             flags,
309 	struct acpi_pointer             *rsdp_address)
310 {
311 	struct acpi_table_desc          table_info;
312 	acpi_status                     status;
313 
314 
315 	ACPI_FUNCTION_TRACE ("acpi_find_root_pointer");
316 
317 
318 	/* Get the RSDP */
319 
320 	status = acpi_tb_find_rsdp (&table_info, flags);
321 	if (ACPI_FAILURE (status)) {
322 		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "RSDP structure not found, %s Flags=%X\n",
323 			acpi_format_exception (status), flags));
324 		return_ACPI_STATUS (AE_NO_ACPI_TABLES);
325 	}
326 
327 	rsdp_address->pointer_type = ACPI_PHYSICAL_POINTER;
328 	rsdp_address->pointer.physical = table_info.physical_address;
329 	return_ACPI_STATUS (AE_OK);
330 }
331 
332 
333 /*******************************************************************************
334  *
335  * FUNCTION:    acpi_tb_scan_memory_for_rsdp
336  *
337  * PARAMETERS:  start_address       - Starting pointer for search
338  *              Length              - Maximum length to search
339  *
340  * RETURN:      Pointer to the RSDP if found, otherwise NULL.
341  *
342  * DESCRIPTION: Search a block of memory for the RSDP signature
343  *
344  ******************************************************************************/
345 
346 u8 *
acpi_tb_scan_memory_for_rsdp(u8 * start_address,u32 length)347 acpi_tb_scan_memory_for_rsdp (
348 	u8                              *start_address,
349 	u32                             length)
350 {
351 	u32                             offset;
352 	u8                              *mem_rover;
353 
354 
355 	ACPI_FUNCTION_TRACE ("tb_scan_memory_for_rsdp");
356 
357 
358 	/* Search from given start addr for the requested length  */
359 
360 	for (offset = 0, mem_rover = start_address;
361 		 offset < length;
362 		 offset += ACPI_RSDP_SCAN_STEP, mem_rover += ACPI_RSDP_SCAN_STEP) {
363 
364 		/* The signature and checksum must both be correct */
365 
366 		if (ACPI_STRNCMP ((char *) mem_rover,
367 				RSDP_SIG, sizeof (RSDP_SIG)-1) == 0 &&
368 			acpi_tb_checksum (mem_rover, ACPI_RSDP_CHECKSUM_LENGTH) == 0) {
369 			/* If so, we have found the RSDP */
370 
371 			ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
372 				"RSDP located at physical address %p\n",mem_rover));
373 			return_PTR (mem_rover);
374 		}
375 	}
376 
377 	/* Searched entire block, no RSDP was found */
378 
379 	ACPI_DEBUG_PRINT ((ACPI_DB_INFO,"Searched entire block, no RSDP was found.\n"));
380 	return_PTR (NULL);
381 }
382 
383 
384 /*******************************************************************************
385  *
386  * FUNCTION:    acpi_tb_find_rsdp
387  *
388  * PARAMETERS:  *table_info             - Where the table info is returned
389  *              Flags                   - Current memory mode (logical vs.
390  *                                        physical addressing)
391  *
392  * RETURN:      Status
393  *
394  * DESCRIPTION: search lower 1_mbyte of memory for the root system descriptor
395  *              pointer structure.  If it is found, set *RSDP to point to it.
396  *
397  *              NOTE: The RSDp must be either in the first 1_k of the Extended
398  *              BIOS Data Area or between E0000 and FFFFF (ACPI 1.0 section
399  *              5.2.2; assertion #421).
400  *
401  ******************************************************************************/
402 
403 acpi_status
acpi_tb_find_rsdp(struct acpi_table_desc * table_info,u32 flags)404 acpi_tb_find_rsdp (
405 	struct acpi_table_desc          *table_info,
406 	u32                             flags)
407 {
408 	u8                              *table_ptr;
409 	u8                              *mem_rover;
410 	u64                             phys_addr;
411 	acpi_status                     status = AE_OK;
412 
413 
414 	ACPI_FUNCTION_TRACE ("tb_find_rsdp");
415 
416 
417 	/*
418 	 * Scan supports either 1) Logical addressing or 2) Physical addressing
419 	 */
420 	if ((flags & ACPI_MEMORY_MODE) == ACPI_LOGICAL_ADDRESSING) {
421 		/*
422 		 * 1) Search EBDA (low memory) paragraphs
423 		 */
424 		status = acpi_os_map_memory ((u64) ACPI_LO_RSDP_WINDOW_BASE, ACPI_LO_RSDP_WINDOW_SIZE,
425 				  (void *) &table_ptr);
426 		if (ACPI_FAILURE (status)) {
427 			ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Could not map memory at %X for length %X\n",
428 				ACPI_LO_RSDP_WINDOW_BASE, ACPI_LO_RSDP_WINDOW_SIZE));
429 			return_ACPI_STATUS (status);
430 		}
431 
432 		mem_rover = acpi_tb_scan_memory_for_rsdp (table_ptr, ACPI_LO_RSDP_WINDOW_SIZE);
433 		acpi_os_unmap_memory (table_ptr, ACPI_LO_RSDP_WINDOW_SIZE);
434 
435 		if (mem_rover) {
436 			/* Found it, return the physical address */
437 
438 			phys_addr = ACPI_LO_RSDP_WINDOW_BASE;
439 			phys_addr += ACPI_PTR_DIFF (mem_rover,table_ptr);
440 
441 			table_info->physical_address = phys_addr;
442 			return_ACPI_STATUS (AE_OK);
443 		}
444 
445 		/*
446 		 * 2) Search upper memory: 16-byte boundaries in E0000h-F0000h
447 		 */
448 		status = acpi_os_map_memory ((u64) ACPI_HI_RSDP_WINDOW_BASE, ACPI_HI_RSDP_WINDOW_SIZE,
449 				  (void *) &table_ptr);
450 		if (ACPI_FAILURE (status)) {
451 			ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Could not map memory at %X for length %X\n",
452 				ACPI_HI_RSDP_WINDOW_BASE, ACPI_HI_RSDP_WINDOW_SIZE));
453 			return_ACPI_STATUS (status);
454 		}
455 
456 		mem_rover = acpi_tb_scan_memory_for_rsdp (table_ptr, ACPI_HI_RSDP_WINDOW_SIZE);
457 		acpi_os_unmap_memory (table_ptr, ACPI_HI_RSDP_WINDOW_SIZE);
458 
459 		if (mem_rover) {
460 			/* Found it, return the physical address */
461 
462 			phys_addr = ACPI_HI_RSDP_WINDOW_BASE;
463 			phys_addr += ACPI_PTR_DIFF (mem_rover, table_ptr);
464 
465 			table_info->physical_address = phys_addr;
466 			return_ACPI_STATUS (AE_OK);
467 		}
468 	}
469 
470 	/*
471 	 * Physical addressing
472 	 */
473 	else {
474 		/*
475 		 * 1) Search EBDA (low memory) paragraphs
476 		 */
477 		mem_rover = acpi_tb_scan_memory_for_rsdp (ACPI_PHYSADDR_TO_PTR (ACPI_LO_RSDP_WINDOW_BASE),
478 				  ACPI_LO_RSDP_WINDOW_SIZE);
479 		if (mem_rover) {
480 			/* Found it, return the physical address */
481 
482 			table_info->physical_address = ACPI_TO_INTEGER (mem_rover);
483 			return_ACPI_STATUS (AE_OK);
484 		}
485 
486 		/*
487 		 * 2) Search upper memory: 16-byte boundaries in E0000h-F0000h
488 		 */
489 		mem_rover = acpi_tb_scan_memory_for_rsdp (ACPI_PHYSADDR_TO_PTR (ACPI_HI_RSDP_WINDOW_BASE),
490 				  ACPI_HI_RSDP_WINDOW_SIZE);
491 		if (mem_rover) {
492 			/* Found it, return the physical address */
493 
494 			table_info->physical_address = ACPI_TO_INTEGER (mem_rover);
495 			return_ACPI_STATUS (AE_OK);
496 		}
497 	}
498 
499 	/* RSDP signature was not found */
500 
501 	return_ACPI_STATUS (AE_NOT_FOUND);
502 }
503 
504 #endif
505 
506