1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2/*******************************************************************************
3 *
4 * Module Name: utresrc - Resource management utilities
5 *
6 ******************************************************************************/
7
8#include <acpi/acpi.h>
9#include "accommon.h"
10#include "acresrc.h"
11
12#define _COMPONENT ACPI_UTILITIES
13ACPI_MODULE_NAME("utresrc")
14
15/*
16 * Base sizes of the raw AML resource descriptors, indexed by resource type.
17 * Zero indicates a reserved (and therefore invalid) resource type.
18 */
19const u8 acpi_gbl_resource_aml_sizes[] = {
20 /* Small descriptors */
21
22 0,
23 0,
24 0,
25 0,
26 ACPI_AML_SIZE_SMALL(struct aml_resource_irq),
27 ACPI_AML_SIZE_SMALL(struct aml_resource_dma),
28 ACPI_AML_SIZE_SMALL(struct aml_resource_start_dependent),
29 ACPI_AML_SIZE_SMALL(struct aml_resource_end_dependent),
30 ACPI_AML_SIZE_SMALL(struct aml_resource_io),
31 ACPI_AML_SIZE_SMALL(struct aml_resource_fixed_io),
32 ACPI_AML_SIZE_SMALL(struct aml_resource_fixed_dma),
33 0,
34 0,
35 0,
36 ACPI_AML_SIZE_SMALL(struct aml_resource_vendor_small),
37 ACPI_AML_SIZE_SMALL(struct aml_resource_end_tag),
38
39 /* Large descriptors */
40
41 0,
42 ACPI_AML_SIZE_LARGE(struct aml_resource_memory24),
43 ACPI_AML_SIZE_LARGE(struct aml_resource_generic_register),
44 0,
45 ACPI_AML_SIZE_LARGE(struct aml_resource_vendor_large),
46 ACPI_AML_SIZE_LARGE(struct aml_resource_memory32),
47 ACPI_AML_SIZE_LARGE(struct aml_resource_fixed_memory32),
48 ACPI_AML_SIZE_LARGE(struct aml_resource_address32),
49 ACPI_AML_SIZE_LARGE(struct aml_resource_address16),
50 ACPI_AML_SIZE_LARGE(struct aml_resource_extended_irq),
51 ACPI_AML_SIZE_LARGE(struct aml_resource_address64),
52 ACPI_AML_SIZE_LARGE(struct aml_resource_extended_address64),
53 ACPI_AML_SIZE_LARGE(struct aml_resource_gpio),
54 ACPI_AML_SIZE_LARGE(struct aml_resource_pin_function),
55 ACPI_AML_SIZE_LARGE(struct aml_resource_common_serialbus),
56 ACPI_AML_SIZE_LARGE(struct aml_resource_pin_config),
57 ACPI_AML_SIZE_LARGE(struct aml_resource_pin_group),
58 ACPI_AML_SIZE_LARGE(struct aml_resource_pin_group_function),
59 ACPI_AML_SIZE_LARGE(struct aml_resource_pin_group_config),
60 ACPI_AML_SIZE_LARGE(struct aml_resource_clock_input),
61
62};
63
64const u8 acpi_gbl_resource_aml_serial_bus_sizes[] = {
65 0,
66 ACPI_AML_SIZE_LARGE(struct aml_resource_i2c_serialbus),
67 ACPI_AML_SIZE_LARGE(struct aml_resource_spi_serialbus),
68 ACPI_AML_SIZE_LARGE(struct aml_resource_uart_serialbus),
69 ACPI_AML_SIZE_LARGE(struct aml_resource_csi2_serialbus),
70};
71
72/*
73 * Resource types, used to validate the resource length field.
74 * The length of fixed-length types must match exactly, variable
75 * lengths must meet the minimum required length, etc.
76 * Zero indicates a reserved (and therefore invalid) resource type.
77 */
78static const u8 acpi_gbl_resource_types[] = {
79 /* Small descriptors */
80
81 0,
82 0,
83 0,
84 0,
85 ACPI_SMALL_VARIABLE_LENGTH, /* 04 IRQ */
86 ACPI_FIXED_LENGTH, /* 05 DMA */
87 ACPI_SMALL_VARIABLE_LENGTH, /* 06 start_dependent_functions */
88 ACPI_FIXED_LENGTH, /* 07 end_dependent_functions */
89 ACPI_FIXED_LENGTH, /* 08 IO */
90 ACPI_FIXED_LENGTH, /* 09 fixed_IO */
91 ACPI_FIXED_LENGTH, /* 0A fixed_DMA */
92 0,
93 0,
94 0,
95 ACPI_VARIABLE_LENGTH, /* 0E vendor_short */
96 ACPI_FIXED_LENGTH, /* 0F end_tag */
97
98 /* Large descriptors */
99
100 0,
101 ACPI_FIXED_LENGTH, /* 01 Memory24 */
102 ACPI_FIXED_LENGTH, /* 02 generic_register */
103 0,
104 ACPI_VARIABLE_LENGTH, /* 04 vendor_long */
105 ACPI_FIXED_LENGTH, /* 05 Memory32 */
106 ACPI_FIXED_LENGTH, /* 06 memory32_fixed */
107 ACPI_VARIABLE_LENGTH, /* 07 Dword* address */
108 ACPI_VARIABLE_LENGTH, /* 08 Word* address */
109 ACPI_VARIABLE_LENGTH, /* 09 extended_IRQ */
110 ACPI_VARIABLE_LENGTH, /* 0A Qword* address */
111 ACPI_FIXED_LENGTH, /* 0B Extended* address */
112 ACPI_VARIABLE_LENGTH, /* 0C Gpio* */
113 ACPI_VARIABLE_LENGTH, /* 0D pin_function */
114 ACPI_VARIABLE_LENGTH, /* 0E *serial_bus */
115 ACPI_VARIABLE_LENGTH, /* 0F pin_config */
116 ACPI_VARIABLE_LENGTH, /* 10 pin_group */
117 ACPI_VARIABLE_LENGTH, /* 11 pin_group_function */
118 ACPI_VARIABLE_LENGTH, /* 12 pin_group_config */
119 ACPI_VARIABLE_LENGTH, /* 13 clock_input */
120};
121
122/*******************************************************************************
123 *
124 * FUNCTION: acpi_ut_walk_aml_resources
125 *
126 * PARAMETERS: walk_state - Current walk info
127 * PARAMETERS: aml - Pointer to the raw AML resource template
128 * aml_length - Length of the entire template
129 * user_function - Called once for each descriptor found. If
130 * NULL, a pointer to the end_tag is returned
131 * context - Passed to user_function
132 *
133 * RETURN: Status
134 *
135 * DESCRIPTION: Walk a raw AML resource list(buffer). User function called
136 * once for each resource found.
137 *
138 ******************************************************************************/
139
140acpi_status
141acpi_ut_walk_aml_resources(struct acpi_walk_state *walk_state,
142 u8 *aml,
143 acpi_size aml_length,
144 acpi_walk_aml_callback user_function, void **context)
145{
146 acpi_status status;
147 u8 *end_aml;
148 u8 resource_index;
149 u32 length;
150 u32 offset = 0;
151 u8 end_tag[2] = { 0x79, 0x00 };
152
153 ACPI_FUNCTION_TRACE(ut_walk_aml_resources);
154
155 /* The absolute minimum resource template is one end_tag descriptor */
156
157 if (aml_length < sizeof(struct aml_resource_end_tag)) {
158 return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
159 }
160
161 /* Point to the end of the resource template buffer */
162
163 end_aml = aml + aml_length;
164
165 /* Walk the byte list, abort on any invalid descriptor type or length */
166
167 while (aml < end_aml) {
168
169 /* Validate the Resource Type and Resource Length */
170
171 status =
172 acpi_ut_validate_resource(walk_state, aml, return_index: &resource_index);
173 if (ACPI_FAILURE(status)) {
174 /*
175 * Exit on failure. Cannot continue because the descriptor
176 * length may be bogus also.
177 */
178 return_ACPI_STATUS(status);
179 }
180
181 /* Get the length of this descriptor */
182
183 length = acpi_ut_get_descriptor_length(aml);
184
185 /* Invoke the user function */
186
187 if (user_function) {
188 status =
189 user_function(aml, length, offset, resource_index,
190 context);
191 if (ACPI_FAILURE(status)) {
192 return_ACPI_STATUS(status);
193 }
194 }
195
196 /* An end_tag descriptor terminates this resource template */
197
198 if (acpi_ut_get_resource_type(aml) ==
199 ACPI_RESOURCE_NAME_END_TAG) {
200 /*
201 * There must be at least one more byte in the buffer for
202 * the 2nd byte of the end_tag
203 */
204 if ((aml + 1) >= end_aml) {
205 return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
206 }
207
208 /*
209 * Don't attempt to perform any validation on the 2nd byte.
210 * Although all known ASL compilers insert a zero for the 2nd
211 * byte, it can also be a checksum (as per the ACPI spec),
212 * and this is occasionally seen in the field. July 2017.
213 */
214
215 /* Return the pointer to the end_tag if requested */
216
217 if (!user_function) {
218 *context = aml;
219 }
220
221 /* Normal exit */
222
223 return_ACPI_STATUS(AE_OK);
224 }
225
226 aml += length;
227 offset += length;
228 }
229
230 /* Did not find an end_tag descriptor */
231
232 if (user_function) {
233
234 /* Insert an end_tag anyway. acpi_rs_get_list_length always leaves room */
235
236 (void)acpi_ut_validate_resource(walk_state, aml: end_tag,
237 return_index: &resource_index);
238 status =
239 user_function(end_tag, 2, offset, resource_index, context);
240 if (ACPI_FAILURE(status)) {
241 return_ACPI_STATUS(status);
242 }
243 }
244
245 return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
246}
247
248/*******************************************************************************
249 *
250 * FUNCTION: acpi_ut_validate_resource
251 *
252 * PARAMETERS: walk_state - Current walk info
253 * aml - Pointer to the raw AML resource descriptor
254 * return_index - Where the resource index is returned. NULL
255 * if the index is not required.
256 *
257 * RETURN: Status, and optionally the Index into the global resource tables
258 *
259 * DESCRIPTION: Validate an AML resource descriptor by checking the Resource
260 * Type and Resource Length. Returns an index into the global
261 * resource information/dispatch tables for later use.
262 *
263 ******************************************************************************/
264
265acpi_status
266acpi_ut_validate_resource(struct acpi_walk_state *walk_state,
267 void *aml, u8 *return_index)
268{
269 union aml_resource *aml_resource;
270 u8 resource_type;
271 u8 resource_index;
272 acpi_rs_length resource_length;
273 acpi_rs_length minimum_resource_length;
274
275 ACPI_FUNCTION_ENTRY();
276
277 /*
278 * 1) Validate the resource_type field (Byte 0)
279 */
280 resource_type = ACPI_GET8(aml);
281
282 /*
283 * Byte 0 contains the descriptor name (Resource Type)
284 * Examine the large/small bit in the resource header
285 */
286 if (resource_type & ACPI_RESOURCE_NAME_LARGE) {
287
288 /* Verify the large resource type (name) against the max */
289
290 if (resource_type > ACPI_RESOURCE_NAME_LARGE_MAX) {
291 goto invalid_resource;
292 }
293
294 /*
295 * Large Resource Type -- bits 6:0 contain the name
296 * Translate range 0x80-0x8B to index range 0x10-0x1B
297 */
298 resource_index = (u8) (resource_type - 0x70);
299 } else {
300 /*
301 * Small Resource Type -- bits 6:3 contain the name
302 * Shift range to index range 0x00-0x0F
303 */
304 resource_index = (u8)
305 ((resource_type & ACPI_RESOURCE_NAME_SMALL_MASK) >> 3);
306 }
307
308 /*
309 * Check validity of the resource type, via acpi_gbl_resource_types.
310 * Zero indicates an invalid resource.
311 */
312 if (!acpi_gbl_resource_types[resource_index]) {
313 goto invalid_resource;
314 }
315
316 /*
317 * Validate the resource_length field. This ensures that the length
318 * is at least reasonable, and guarantees that it is non-zero.
319 */
320 resource_length = acpi_ut_get_resource_length(aml);
321 minimum_resource_length = acpi_gbl_resource_aml_sizes[resource_index];
322
323 /* Validate based upon the type of resource - fixed length or variable */
324
325 switch (acpi_gbl_resource_types[resource_index]) {
326 case ACPI_FIXED_LENGTH:
327
328 /* Fixed length resource, length must match exactly */
329
330 if (resource_length != minimum_resource_length) {
331 goto bad_resource_length;
332 }
333 break;
334
335 case ACPI_VARIABLE_LENGTH:
336
337 /* Variable length resource, length must be at least the minimum */
338
339 if (resource_length < minimum_resource_length) {
340 goto bad_resource_length;
341 }
342 break;
343
344 case ACPI_SMALL_VARIABLE_LENGTH:
345
346 /* Small variable length resource, length can be (Min) or (Min-1) */
347
348 if ((resource_length > minimum_resource_length) ||
349 (resource_length < (minimum_resource_length - 1))) {
350 goto bad_resource_length;
351 }
352 break;
353
354 default:
355
356 /* Shouldn't happen (because of validation earlier), but be sure */
357
358 goto invalid_resource;
359 }
360
361 aml_resource = ACPI_CAST_PTR(union aml_resource, aml);
362 if (resource_type == ACPI_RESOURCE_NAME_SERIAL_BUS) {
363
364 /* Avoid undefined behavior: member access within misaligned address */
365
366 struct aml_resource_common_serialbus common_serial_bus;
367 memcpy(&common_serial_bus, aml_resource,
368 sizeof(common_serial_bus));
369
370 /* Validate the bus_type field */
371
372 if ((common_serial_bus.type == 0) ||
373 (common_serial_bus.type > AML_RESOURCE_MAX_SERIALBUSTYPE)) {
374 if (walk_state) {
375 ACPI_ERROR((AE_INFO,
376 "Invalid/unsupported SerialBus resource descriptor: BusType 0x%2.2X",
377 common_serial_bus.type));
378 }
379 return (AE_AML_INVALID_RESOURCE_TYPE);
380 }
381 }
382
383 /* Optionally return the resource table index */
384
385 if (return_index) {
386 *return_index = resource_index;
387 }
388
389 return (AE_OK);
390
391invalid_resource:
392
393 if (walk_state) {
394 ACPI_ERROR((AE_INFO,
395 "Invalid/unsupported resource descriptor: Type 0x%2.2X",
396 resource_type));
397 }
398 return (AE_AML_INVALID_RESOURCE_TYPE);
399
400bad_resource_length:
401
402 if (walk_state) {
403 ACPI_ERROR((AE_INFO,
404 "Invalid resource descriptor length: Type "
405 "0x%2.2X, Length 0x%4.4X, MinLength 0x%4.4X",
406 resource_type, resource_length,
407 minimum_resource_length));
408 }
409 return (AE_AML_BAD_RESOURCE_LENGTH);
410}
411
412/*******************************************************************************
413 *
414 * FUNCTION: acpi_ut_get_resource_type
415 *
416 * PARAMETERS: aml - Pointer to the raw AML resource descriptor
417 *
418 * RETURN: The Resource Type with no extraneous bits (except the
419 * Large/Small descriptor bit -- this is left alone)
420 *
421 * DESCRIPTION: Extract the Resource Type/Name from the first byte of
422 * a resource descriptor.
423 *
424 ******************************************************************************/
425
426u8 acpi_ut_get_resource_type(void *aml)
427{
428 ACPI_FUNCTION_ENTRY();
429
430 /*
431 * Byte 0 contains the descriptor name (Resource Type)
432 * Examine the large/small bit in the resource header
433 */
434 if (ACPI_GET8(aml) & ACPI_RESOURCE_NAME_LARGE) {
435
436 /* Large Resource Type -- bits 6:0 contain the name */
437
438 return (ACPI_GET8(aml));
439 } else {
440 /* Small Resource Type -- bits 6:3 contain the name */
441
442 return ((u8) (ACPI_GET8(aml) & ACPI_RESOURCE_NAME_SMALL_MASK));
443 }
444}
445
446/*******************************************************************************
447 *
448 * FUNCTION: acpi_ut_get_resource_length
449 *
450 * PARAMETERS: aml - Pointer to the raw AML resource descriptor
451 *
452 * RETURN: Byte Length
453 *
454 * DESCRIPTION: Get the "Resource Length" of a raw AML descriptor. By
455 * definition, this does not include the size of the descriptor
456 * header or the length field itself.
457 *
458 ******************************************************************************/
459
460u16 acpi_ut_get_resource_length(void *aml)
461{
462 acpi_rs_length resource_length;
463
464 ACPI_FUNCTION_ENTRY();
465
466 /*
467 * Byte 0 contains the descriptor name (Resource Type)
468 * Examine the large/small bit in the resource header
469 */
470 if (ACPI_GET8(aml) & ACPI_RESOURCE_NAME_LARGE) {
471
472 /* Large Resource type -- bytes 1-2 contain the 16-bit length */
473
474 ACPI_MOVE_16_TO_16(&resource_length, ACPI_ADD_PTR(u8, aml, 1));
475
476 } else {
477 /* Small Resource type -- bits 2:0 of byte 0 contain the length */
478
479 resource_length = (u16) (ACPI_GET8(aml) &
480 ACPI_RESOURCE_NAME_SMALL_LENGTH_MASK);
481 }
482
483 return (resource_length);
484}
485
486/*******************************************************************************
487 *
488 * FUNCTION: acpi_ut_get_resource_header_length
489 *
490 * PARAMETERS: aml - Pointer to the raw AML resource descriptor
491 *
492 * RETURN: Length of the AML header (depends on large/small descriptor)
493 *
494 * DESCRIPTION: Get the length of the header for this resource.
495 *
496 ******************************************************************************/
497
498u8 acpi_ut_get_resource_header_length(void *aml)
499{
500 ACPI_FUNCTION_ENTRY();
501
502 /* Examine the large/small bit in the resource header */
503
504 if (ACPI_GET8(aml) & ACPI_RESOURCE_NAME_LARGE) {
505 return (sizeof(struct aml_resource_large_header));
506 } else {
507 return (sizeof(struct aml_resource_small_header));
508 }
509}
510
511/*******************************************************************************
512 *
513 * FUNCTION: acpi_ut_get_descriptor_length
514 *
515 * PARAMETERS: aml - Pointer to the raw AML resource descriptor
516 *
517 * RETURN: Byte length
518 *
519 * DESCRIPTION: Get the total byte length of a raw AML descriptor, including the
520 * length of the descriptor header and the length field itself.
521 * Used to walk descriptor lists.
522 *
523 ******************************************************************************/
524
525u32 acpi_ut_get_descriptor_length(void *aml)
526{
527 ACPI_FUNCTION_ENTRY();
528
529 /*
530 * Get the Resource Length (does not include header length) and add
531 * the header length (depends on if this is a small or large resource)
532 */
533 return (acpi_ut_get_resource_length(aml) +
534 acpi_ut_get_resource_header_length(aml));
535}
536
537/*******************************************************************************
538 *
539 * FUNCTION: acpi_ut_get_resource_end_tag
540 *
541 * PARAMETERS: obj_desc - The resource template buffer object
542 * end_tag - Where the pointer to the end_tag is returned
543 *
544 * RETURN: Status, pointer to the end tag
545 *
546 * DESCRIPTION: Find the end_tag resource descriptor in an AML resource template
547 * Note: allows a buffer length of zero.
548 *
549 ******************************************************************************/
550
551acpi_status
552acpi_ut_get_resource_end_tag(union acpi_operand_object *obj_desc, u8 **end_tag)
553{
554 acpi_status status;
555
556 ACPI_FUNCTION_TRACE(ut_get_resource_end_tag);
557
558 /* Allow a buffer length of zero */
559
560 if (!obj_desc->buffer.length) {
561 *end_tag = obj_desc->buffer.pointer;
562 return_ACPI_STATUS(AE_OK);
563 }
564
565 /* Validate the template and get a pointer to the end_tag */
566
567 status = acpi_ut_walk_aml_resources(NULL, aml: obj_desc->buffer.pointer,
568 aml_length: obj_desc->buffer.length, NULL,
569 context: (void **)end_tag);
570
571 return_ACPI_STATUS(status);
572}
573

source code of linux/drivers/acpi/acpica/utresrc.c