xref: /openbmc/linux/drivers/acpi/resource.c (revision 413d6ed3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * drivers/acpi/resource.c - ACPI device resources interpretation.
4  *
5  * Copyright (C) 2012, Intel Corp.
6  * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
7  *
8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9  *
10  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11  */
12 
13 #include <linux/acpi.h>
14 #include <linux/device.h>
15 #include <linux/export.h>
16 #include <linux/ioport.h>
17 #include <linux/slab.h>
18 #include <linux/irq.h>
19 
20 #ifdef CONFIG_X86
21 #define valid_IRQ(i) (((i) != 0) && ((i) != 2))
22 static inline bool acpi_iospace_resource_valid(struct resource *res)
23 {
24 	/* On X86 IO space is limited to the [0 - 64K] IO port range */
25 	return res->end < 0x10003;
26 }
27 #else
28 #define valid_IRQ(i) (true)
29 /*
30  * ACPI IO descriptors on arches other than X86 contain MMIO CPU physical
31  * addresses mapping IO space in CPU physical address space, IO space
32  * resources can be placed anywhere in the 64-bit physical address space.
33  */
34 static inline bool
35 acpi_iospace_resource_valid(struct resource *res) { return true; }
36 #endif
37 
38 #if IS_ENABLED(CONFIG_ACPI_GENERIC_GSI)
39 static inline bool is_gsi(struct acpi_resource_extended_irq *ext_irq)
40 {
41 	return ext_irq->resource_source.string_length == 0 &&
42 	       ext_irq->producer_consumer == ACPI_CONSUMER;
43 }
44 #else
45 static inline bool is_gsi(struct acpi_resource_extended_irq *ext_irq)
46 {
47 	return true;
48 }
49 #endif
50 
51 static bool acpi_dev_resource_len_valid(u64 start, u64 end, u64 len, bool io)
52 {
53 	u64 reslen = end - start + 1;
54 
55 	/*
56 	 * CHECKME: len might be required to check versus a minimum
57 	 * length as well. 1 for io is fine, but for memory it does
58 	 * not make any sense at all.
59 	 * Note: some BIOSes report incorrect length for ACPI address space
60 	 * descriptor, so remove check of 'reslen == len' to avoid regression.
61 	 */
62 	if (len && reslen && start <= end)
63 		return true;
64 
65 	pr_debug("ACPI: invalid or unassigned resource %s [%016llx - %016llx] length [%016llx]\n",
66 		io ? "io" : "mem", start, end, len);
67 
68 	return false;
69 }
70 
71 static void acpi_dev_memresource_flags(struct resource *res, u64 len,
72 				       u8 write_protect)
73 {
74 	res->flags = IORESOURCE_MEM;
75 
76 	if (!acpi_dev_resource_len_valid(res->start, res->end, len, false))
77 		res->flags |= IORESOURCE_DISABLED | IORESOURCE_UNSET;
78 
79 	if (write_protect == ACPI_READ_WRITE_MEMORY)
80 		res->flags |= IORESOURCE_MEM_WRITEABLE;
81 }
82 
83 static void acpi_dev_get_memresource(struct resource *res, u64 start, u64 len,
84 				     u8 write_protect)
85 {
86 	res->start = start;
87 	res->end = start + len - 1;
88 	acpi_dev_memresource_flags(res, len, write_protect);
89 }
90 
91 /**
92  * acpi_dev_resource_memory - Extract ACPI memory resource information.
93  * @ares: Input ACPI resource object.
94  * @res: Output generic resource object.
95  *
96  * Check if the given ACPI resource object represents a memory resource and
97  * if that's the case, use the information in it to populate the generic
98  * resource object pointed to by @res.
99  *
100  * Return:
101  * 1) false with res->flags setting to zero: not the expected resource type
102  * 2) false with IORESOURCE_DISABLED in res->flags: valid unassigned resource
103  * 3) true: valid assigned resource
104  */
105 bool acpi_dev_resource_memory(struct acpi_resource *ares, struct resource *res)
106 {
107 	struct acpi_resource_memory24 *memory24;
108 	struct acpi_resource_memory32 *memory32;
109 	struct acpi_resource_fixed_memory32 *fixed_memory32;
110 
111 	switch (ares->type) {
112 	case ACPI_RESOURCE_TYPE_MEMORY24:
113 		memory24 = &ares->data.memory24;
114 		acpi_dev_get_memresource(res, memory24->minimum << 8,
115 					 memory24->address_length << 8,
116 					 memory24->write_protect);
117 		break;
118 	case ACPI_RESOURCE_TYPE_MEMORY32:
119 		memory32 = &ares->data.memory32;
120 		acpi_dev_get_memresource(res, memory32->minimum,
121 					 memory32->address_length,
122 					 memory32->write_protect);
123 		break;
124 	case ACPI_RESOURCE_TYPE_FIXED_MEMORY32:
125 		fixed_memory32 = &ares->data.fixed_memory32;
126 		acpi_dev_get_memresource(res, fixed_memory32->address,
127 					 fixed_memory32->address_length,
128 					 fixed_memory32->write_protect);
129 		break;
130 	default:
131 		res->flags = 0;
132 		return false;
133 	}
134 
135 	return !(res->flags & IORESOURCE_DISABLED);
136 }
137 EXPORT_SYMBOL_GPL(acpi_dev_resource_memory);
138 
139 static void acpi_dev_ioresource_flags(struct resource *res, u64 len,
140 				      u8 io_decode, u8 translation_type)
141 {
142 	res->flags = IORESOURCE_IO;
143 
144 	if (!acpi_dev_resource_len_valid(res->start, res->end, len, true))
145 		res->flags |= IORESOURCE_DISABLED | IORESOURCE_UNSET;
146 
147 	if (!acpi_iospace_resource_valid(res))
148 		res->flags |= IORESOURCE_DISABLED | IORESOURCE_UNSET;
149 
150 	if (io_decode == ACPI_DECODE_16)
151 		res->flags |= IORESOURCE_IO_16BIT_ADDR;
152 	if (translation_type == ACPI_SPARSE_TRANSLATION)
153 		res->flags |= IORESOURCE_IO_SPARSE;
154 }
155 
156 static void acpi_dev_get_ioresource(struct resource *res, u64 start, u64 len,
157 				    u8 io_decode)
158 {
159 	res->start = start;
160 	res->end = start + len - 1;
161 	acpi_dev_ioresource_flags(res, len, io_decode, 0);
162 }
163 
164 /**
165  * acpi_dev_resource_io - Extract ACPI I/O resource information.
166  * @ares: Input ACPI resource object.
167  * @res: Output generic resource object.
168  *
169  * Check if the given ACPI resource object represents an I/O resource and
170  * if that's the case, use the information in it to populate the generic
171  * resource object pointed to by @res.
172  *
173  * Return:
174  * 1) false with res->flags setting to zero: not the expected resource type
175  * 2) false with IORESOURCE_DISABLED in res->flags: valid unassigned resource
176  * 3) true: valid assigned resource
177  */
178 bool acpi_dev_resource_io(struct acpi_resource *ares, struct resource *res)
179 {
180 	struct acpi_resource_io *io;
181 	struct acpi_resource_fixed_io *fixed_io;
182 
183 	switch (ares->type) {
184 	case ACPI_RESOURCE_TYPE_IO:
185 		io = &ares->data.io;
186 		acpi_dev_get_ioresource(res, io->minimum,
187 					io->address_length,
188 					io->io_decode);
189 		break;
190 	case ACPI_RESOURCE_TYPE_FIXED_IO:
191 		fixed_io = &ares->data.fixed_io;
192 		acpi_dev_get_ioresource(res, fixed_io->address,
193 					fixed_io->address_length,
194 					ACPI_DECODE_10);
195 		break;
196 	default:
197 		res->flags = 0;
198 		return false;
199 	}
200 
201 	return !(res->flags & IORESOURCE_DISABLED);
202 }
203 EXPORT_SYMBOL_GPL(acpi_dev_resource_io);
204 
205 static bool acpi_decode_space(struct resource_win *win,
206 			      struct acpi_resource_address *addr,
207 			      struct acpi_address64_attribute *attr)
208 {
209 	u8 iodec = attr->granularity == 0xfff ? ACPI_DECODE_10 : ACPI_DECODE_16;
210 	bool wp = addr->info.mem.write_protect;
211 	u64 len = attr->address_length;
212 	u64 start, end, offset = 0;
213 	struct resource *res = &win->res;
214 
215 	/*
216 	 * Filter out invalid descriptor according to ACPI Spec 5.0, section
217 	 * 6.4.3.5 Address Space Resource Descriptors.
218 	 */
219 	if ((addr->min_address_fixed != addr->max_address_fixed && len) ||
220 	    (addr->min_address_fixed && addr->max_address_fixed && !len))
221 		pr_debug("ACPI: Invalid address space min_addr_fix %d, max_addr_fix %d, len %llx\n",
222 			 addr->min_address_fixed, addr->max_address_fixed, len);
223 
224 	/*
225 	 * For bridges that translate addresses across the bridge,
226 	 * translation_offset is the offset that must be added to the
227 	 * address on the secondary side to obtain the address on the
228 	 * primary side. Non-bridge devices must list 0 for all Address
229 	 * Translation offset bits.
230 	 */
231 	if (addr->producer_consumer == ACPI_PRODUCER)
232 		offset = attr->translation_offset;
233 	else if (attr->translation_offset)
234 		pr_debug("ACPI: translation_offset(%lld) is invalid for non-bridge device.\n",
235 			 attr->translation_offset);
236 	start = attr->minimum + offset;
237 	end = attr->maximum + offset;
238 
239 	win->offset = offset;
240 	res->start = start;
241 	res->end = end;
242 	if (sizeof(resource_size_t) < sizeof(u64) &&
243 	    (offset != win->offset || start != res->start || end != res->end)) {
244 		pr_warn("acpi resource window ([%#llx-%#llx] ignored, not CPU addressable)\n",
245 			attr->minimum, attr->maximum);
246 		return false;
247 	}
248 
249 	switch (addr->resource_type) {
250 	case ACPI_MEMORY_RANGE:
251 		acpi_dev_memresource_flags(res, len, wp);
252 		break;
253 	case ACPI_IO_RANGE:
254 		acpi_dev_ioresource_flags(res, len, iodec,
255 					  addr->info.io.translation_type);
256 		break;
257 	case ACPI_BUS_NUMBER_RANGE:
258 		res->flags = IORESOURCE_BUS;
259 		break;
260 	default:
261 		return false;
262 	}
263 
264 	if (addr->producer_consumer == ACPI_PRODUCER)
265 		res->flags |= IORESOURCE_WINDOW;
266 
267 	if (addr->info.mem.caching == ACPI_PREFETCHABLE_MEMORY)
268 		res->flags |= IORESOURCE_PREFETCH;
269 
270 	return !(res->flags & IORESOURCE_DISABLED);
271 }
272 
273 /**
274  * acpi_dev_resource_address_space - Extract ACPI address space information.
275  * @ares: Input ACPI resource object.
276  * @win: Output generic resource object.
277  *
278  * Check if the given ACPI resource object represents an address space resource
279  * and if that's the case, use the information in it to populate the generic
280  * resource object pointed to by @win.
281  *
282  * Return:
283  * 1) false with win->res.flags setting to zero: not the expected resource type
284  * 2) false with IORESOURCE_DISABLED in win->res.flags: valid unassigned
285  *    resource
286  * 3) true: valid assigned resource
287  */
288 bool acpi_dev_resource_address_space(struct acpi_resource *ares,
289 				     struct resource_win *win)
290 {
291 	struct acpi_resource_address64 addr;
292 
293 	win->res.flags = 0;
294 	if (ACPI_FAILURE(acpi_resource_to_address64(ares, &addr)))
295 		return false;
296 
297 	return acpi_decode_space(win, (struct acpi_resource_address *)&addr,
298 				 &addr.address);
299 }
300 EXPORT_SYMBOL_GPL(acpi_dev_resource_address_space);
301 
302 /**
303  * acpi_dev_resource_ext_address_space - Extract ACPI address space information.
304  * @ares: Input ACPI resource object.
305  * @win: Output generic resource object.
306  *
307  * Check if the given ACPI resource object represents an extended address space
308  * resource and if that's the case, use the information in it to populate the
309  * generic resource object pointed to by @win.
310  *
311  * Return:
312  * 1) false with win->res.flags setting to zero: not the expected resource type
313  * 2) false with IORESOURCE_DISABLED in win->res.flags: valid unassigned
314  *    resource
315  * 3) true: valid assigned resource
316  */
317 bool acpi_dev_resource_ext_address_space(struct acpi_resource *ares,
318 					 struct resource_win *win)
319 {
320 	struct acpi_resource_extended_address64 *ext_addr;
321 
322 	win->res.flags = 0;
323 	if (ares->type != ACPI_RESOURCE_TYPE_EXTENDED_ADDRESS64)
324 		return false;
325 
326 	ext_addr = &ares->data.ext_address64;
327 
328 	return acpi_decode_space(win, (struct acpi_resource_address *)ext_addr,
329 				 &ext_addr->address);
330 }
331 EXPORT_SYMBOL_GPL(acpi_dev_resource_ext_address_space);
332 
333 /**
334  * acpi_dev_irq_flags - Determine IRQ resource flags.
335  * @triggering: Triggering type as provided by ACPI.
336  * @polarity: Interrupt polarity as provided by ACPI.
337  * @shareable: Whether or not the interrupt is shareable.
338  */
339 unsigned long acpi_dev_irq_flags(u8 triggering, u8 polarity, u8 shareable)
340 {
341 	unsigned long flags;
342 
343 	if (triggering == ACPI_LEVEL_SENSITIVE)
344 		flags = polarity == ACPI_ACTIVE_LOW ?
345 			IORESOURCE_IRQ_LOWLEVEL : IORESOURCE_IRQ_HIGHLEVEL;
346 	else
347 		flags = polarity == ACPI_ACTIVE_LOW ?
348 			IORESOURCE_IRQ_LOWEDGE : IORESOURCE_IRQ_HIGHEDGE;
349 
350 	if (shareable == ACPI_SHARED)
351 		flags |= IORESOURCE_IRQ_SHAREABLE;
352 
353 	return flags | IORESOURCE_IRQ;
354 }
355 EXPORT_SYMBOL_GPL(acpi_dev_irq_flags);
356 
357 /**
358  * acpi_dev_get_irq_type - Determine irq type.
359  * @triggering: Triggering type as provided by ACPI.
360  * @polarity: Interrupt polarity as provided by ACPI.
361  */
362 unsigned int acpi_dev_get_irq_type(int triggering, int polarity)
363 {
364 	switch (polarity) {
365 	case ACPI_ACTIVE_LOW:
366 		return triggering == ACPI_EDGE_SENSITIVE ?
367 		       IRQ_TYPE_EDGE_FALLING :
368 		       IRQ_TYPE_LEVEL_LOW;
369 	case ACPI_ACTIVE_HIGH:
370 		return triggering == ACPI_EDGE_SENSITIVE ?
371 		       IRQ_TYPE_EDGE_RISING :
372 		       IRQ_TYPE_LEVEL_HIGH;
373 	case ACPI_ACTIVE_BOTH:
374 		if (triggering == ACPI_EDGE_SENSITIVE)
375 			return IRQ_TYPE_EDGE_BOTH;
376 		fallthrough;
377 	default:
378 		return IRQ_TYPE_NONE;
379 	}
380 }
381 EXPORT_SYMBOL_GPL(acpi_dev_get_irq_type);
382 
383 static void acpi_dev_get_irqresource(struct resource *res, u32 gsi,
384 				     u8 triggering, u8 polarity, u8 shareable,
385 				     bool legacy)
386 {
387 	int irq, p, t;
388 
389 	if (!valid_IRQ(gsi)) {
390 		irqresource_disabled(res, gsi);
391 		return;
392 	}
393 
394 	/*
395 	 * In IO-APIC mode, use overridden attribute. Two reasons:
396 	 * 1. BIOS bug in DSDT
397 	 * 2. BIOS uses IO-APIC mode Interrupt Source Override
398 	 *
399 	 * We do this only if we are dealing with IRQ() or IRQNoFlags()
400 	 * resource (the legacy ISA resources). With modern ACPI 5 devices
401 	 * using extended IRQ descriptors we take the IRQ configuration
402 	 * from _CRS directly.
403 	 */
404 	if (legacy && !acpi_get_override_irq(gsi, &t, &p)) {
405 		u8 trig = t ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE;
406 		u8 pol = p ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH;
407 
408 		if (triggering != trig || polarity != pol) {
409 			pr_warn("ACPI: IRQ %d override to %s, %s\n", gsi,
410 				t ? "level" : "edge", p ? "low" : "high");
411 			triggering = trig;
412 			polarity = pol;
413 		}
414 	}
415 
416 	res->flags = acpi_dev_irq_flags(triggering, polarity, shareable);
417 	irq = acpi_register_gsi(NULL, gsi, triggering, polarity);
418 	if (irq >= 0) {
419 		res->start = irq;
420 		res->end = irq;
421 	} else {
422 		irqresource_disabled(res, gsi);
423 	}
424 }
425 
426 /**
427  * acpi_dev_resource_interrupt - Extract ACPI interrupt resource information.
428  * @ares: Input ACPI resource object.
429  * @index: Index into the array of GSIs represented by the resource.
430  * @res: Output generic resource object.
431  *
432  * Check if the given ACPI resource object represents an interrupt resource
433  * and @index does not exceed the resource's interrupt count (true is returned
434  * in that case regardless of the results of the other checks)).  If that's the
435  * case, register the GSI corresponding to @index from the array of interrupts
436  * represented by the resource and populate the generic resource object pointed
437  * to by @res accordingly.  If the registration of the GSI is not successful,
438  * IORESOURCE_DISABLED will be set it that object's flags.
439  *
440  * Return:
441  * 1) false with res->flags setting to zero: not the expected resource type
442  * 2) false with IORESOURCE_DISABLED in res->flags: valid unassigned resource
443  * 3) true: valid assigned resource
444  */
445 bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
446 				 struct resource *res)
447 {
448 	struct acpi_resource_irq *irq;
449 	struct acpi_resource_extended_irq *ext_irq;
450 
451 	switch (ares->type) {
452 	case ACPI_RESOURCE_TYPE_IRQ:
453 		/*
454 		 * Per spec, only one interrupt per descriptor is allowed in
455 		 * _CRS, but some firmware violates this, so parse them all.
456 		 */
457 		irq = &ares->data.irq;
458 		if (index >= irq->interrupt_count) {
459 			irqresource_disabled(res, 0);
460 			return false;
461 		}
462 		acpi_dev_get_irqresource(res, irq->interrupts[index],
463 					 irq->triggering, irq->polarity,
464 					 irq->shareable, true);
465 		break;
466 	case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
467 		ext_irq = &ares->data.extended_irq;
468 		if (index >= ext_irq->interrupt_count) {
469 			irqresource_disabled(res, 0);
470 			return false;
471 		}
472 		if (is_gsi(ext_irq))
473 			acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
474 					 ext_irq->triggering, ext_irq->polarity,
475 					 ext_irq->shareable, false);
476 		else
477 			irqresource_disabled(res, 0);
478 		break;
479 	default:
480 		res->flags = 0;
481 		return false;
482 	}
483 
484 	return true;
485 }
486 EXPORT_SYMBOL_GPL(acpi_dev_resource_interrupt);
487 
488 /**
489  * acpi_dev_free_resource_list - Free resource from %acpi_dev_get_resources().
490  * @list: The head of the resource list to free.
491  */
492 void acpi_dev_free_resource_list(struct list_head *list)
493 {
494 	resource_list_free(list);
495 }
496 EXPORT_SYMBOL_GPL(acpi_dev_free_resource_list);
497 
498 struct res_proc_context {
499 	struct list_head *list;
500 	int (*preproc)(struct acpi_resource *, void *);
501 	void *preproc_data;
502 	int count;
503 	int error;
504 };
505 
506 static acpi_status acpi_dev_new_resource_entry(struct resource_win *win,
507 					       struct res_proc_context *c)
508 {
509 	struct resource_entry *rentry;
510 
511 	rentry = resource_list_create_entry(NULL, 0);
512 	if (!rentry) {
513 		c->error = -ENOMEM;
514 		return AE_NO_MEMORY;
515 	}
516 	*rentry->res = win->res;
517 	rentry->offset = win->offset;
518 	resource_list_add_tail(rentry, c->list);
519 	c->count++;
520 	return AE_OK;
521 }
522 
523 static acpi_status acpi_dev_process_resource(struct acpi_resource *ares,
524 					     void *context)
525 {
526 	struct res_proc_context *c = context;
527 	struct resource_win win;
528 	struct resource *res = &win.res;
529 	int i;
530 
531 	if (c->preproc) {
532 		int ret;
533 
534 		ret = c->preproc(ares, c->preproc_data);
535 		if (ret < 0) {
536 			c->error = ret;
537 			return AE_ABORT_METHOD;
538 		} else if (ret > 0) {
539 			return AE_OK;
540 		}
541 	}
542 
543 	memset(&win, 0, sizeof(win));
544 
545 	if (acpi_dev_resource_memory(ares, res)
546 	    || acpi_dev_resource_io(ares, res)
547 	    || acpi_dev_resource_address_space(ares, &win)
548 	    || acpi_dev_resource_ext_address_space(ares, &win))
549 		return acpi_dev_new_resource_entry(&win, c);
550 
551 	for (i = 0; acpi_dev_resource_interrupt(ares, i, res); i++) {
552 		acpi_status status;
553 
554 		status = acpi_dev_new_resource_entry(&win, c);
555 		if (ACPI_FAILURE(status))
556 			return status;
557 	}
558 
559 	return AE_OK;
560 }
561 
562 static int __acpi_dev_get_resources(struct acpi_device *adev,
563 				    struct list_head *list,
564 				    int (*preproc)(struct acpi_resource *, void *),
565 				    void *preproc_data, char *method)
566 {
567 	struct res_proc_context c;
568 	acpi_status status;
569 
570 	if (!adev || !adev->handle || !list_empty(list))
571 		return -EINVAL;
572 
573 	if (!acpi_has_method(adev->handle, method))
574 		return 0;
575 
576 	c.list = list;
577 	c.preproc = preproc;
578 	c.preproc_data = preproc_data;
579 	c.count = 0;
580 	c.error = 0;
581 	status = acpi_walk_resources(adev->handle, method,
582 				     acpi_dev_process_resource, &c);
583 	if (ACPI_FAILURE(status)) {
584 		acpi_dev_free_resource_list(list);
585 		return c.error ? c.error : -EIO;
586 	}
587 
588 	return c.count;
589 }
590 
591 /**
592  * acpi_dev_get_resources - Get current resources of a device.
593  * @adev: ACPI device node to get the resources for.
594  * @list: Head of the resultant list of resources (must be empty).
595  * @preproc: The caller's preprocessing routine.
596  * @preproc_data: Pointer passed to the caller's preprocessing routine.
597  *
598  * Evaluate the _CRS method for the given device node and process its output by
599  * (1) executing the @preproc() routine provided by the caller, passing the
600  * resource pointer and @preproc_data to it as arguments, for each ACPI resource
601  * returned and (2) converting all of the returned ACPI resources into struct
602  * resource objects if possible.  If the return value of @preproc() in step (1)
603  * is different from 0, step (2) is not applied to the given ACPI resource and
604  * if that value is negative, the whole processing is aborted and that value is
605  * returned as the final error code.
606  *
607  * The resultant struct resource objects are put on the list pointed to by
608  * @list, that must be empty initially, as members of struct resource_entry
609  * objects.  Callers of this routine should use %acpi_dev_free_resource_list() to
610  * free that list.
611  *
612  * The number of resources in the output list is returned on success, an error
613  * code reflecting the error condition is returned otherwise.
614  */
615 int acpi_dev_get_resources(struct acpi_device *adev, struct list_head *list,
616 			   int (*preproc)(struct acpi_resource *, void *),
617 			   void *preproc_data)
618 {
619 	return __acpi_dev_get_resources(adev, list, preproc, preproc_data,
620 					METHOD_NAME__CRS);
621 }
622 EXPORT_SYMBOL_GPL(acpi_dev_get_resources);
623 
624 static int is_memory(struct acpi_resource *ares, void *not_used)
625 {
626 	struct resource_win win;
627 	struct resource *res = &win.res;
628 
629 	memset(&win, 0, sizeof(win));
630 
631 	return !(acpi_dev_resource_memory(ares, res)
632 	       || acpi_dev_resource_address_space(ares, &win)
633 	       || acpi_dev_resource_ext_address_space(ares, &win));
634 }
635 
636 /**
637  * acpi_dev_get_dma_resources - Get current DMA resources of a device.
638  * @adev: ACPI device node to get the resources for.
639  * @list: Head of the resultant list of resources (must be empty).
640  *
641  * Evaluate the _DMA method for the given device node and process its
642  * output.
643  *
644  * The resultant struct resource objects are put on the list pointed to
645  * by @list, that must be empty initially, as members of struct
646  * resource_entry objects.  Callers of this routine should use
647  * %acpi_dev_free_resource_list() to free that list.
648  *
649  * The number of resources in the output list is returned on success,
650  * an error code reflecting the error condition is returned otherwise.
651  */
652 int acpi_dev_get_dma_resources(struct acpi_device *adev, struct list_head *list)
653 {
654 	return __acpi_dev_get_resources(adev, list, is_memory, NULL,
655 					METHOD_NAME__DMA);
656 }
657 EXPORT_SYMBOL_GPL(acpi_dev_get_dma_resources);
658 
659 /**
660  * acpi_dev_filter_resource_type - Filter ACPI resource according to resource
661  *				   types
662  * @ares: Input ACPI resource object.
663  * @types: Valid resource types of IORESOURCE_XXX
664  *
665  * This is a helper function to support acpi_dev_get_resources(), which filters
666  * ACPI resource objects according to resource types.
667  */
668 int acpi_dev_filter_resource_type(struct acpi_resource *ares,
669 				  unsigned long types)
670 {
671 	unsigned long type = 0;
672 
673 	switch (ares->type) {
674 	case ACPI_RESOURCE_TYPE_MEMORY24:
675 	case ACPI_RESOURCE_TYPE_MEMORY32:
676 	case ACPI_RESOURCE_TYPE_FIXED_MEMORY32:
677 		type = IORESOURCE_MEM;
678 		break;
679 	case ACPI_RESOURCE_TYPE_IO:
680 	case ACPI_RESOURCE_TYPE_FIXED_IO:
681 		type = IORESOURCE_IO;
682 		break;
683 	case ACPI_RESOURCE_TYPE_IRQ:
684 	case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
685 		type = IORESOURCE_IRQ;
686 		break;
687 	case ACPI_RESOURCE_TYPE_DMA:
688 	case ACPI_RESOURCE_TYPE_FIXED_DMA:
689 		type = IORESOURCE_DMA;
690 		break;
691 	case ACPI_RESOURCE_TYPE_GENERIC_REGISTER:
692 		type = IORESOURCE_REG;
693 		break;
694 	case ACPI_RESOURCE_TYPE_ADDRESS16:
695 	case ACPI_RESOURCE_TYPE_ADDRESS32:
696 	case ACPI_RESOURCE_TYPE_ADDRESS64:
697 	case ACPI_RESOURCE_TYPE_EXTENDED_ADDRESS64:
698 		if (ares->data.address.resource_type == ACPI_MEMORY_RANGE)
699 			type = IORESOURCE_MEM;
700 		else if (ares->data.address.resource_type == ACPI_IO_RANGE)
701 			type = IORESOURCE_IO;
702 		else if (ares->data.address.resource_type ==
703 			 ACPI_BUS_NUMBER_RANGE)
704 			type = IORESOURCE_BUS;
705 		break;
706 	default:
707 		break;
708 	}
709 
710 	return (type & types) ? 0 : 1;
711 }
712 EXPORT_SYMBOL_GPL(acpi_dev_filter_resource_type);
713 
714 static int acpi_dev_consumes_res(struct acpi_device *adev, struct resource *res)
715 {
716 	struct list_head resource_list;
717 	struct resource_entry *rentry;
718 	int ret, found = 0;
719 
720 	INIT_LIST_HEAD(&resource_list);
721 	ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
722 	if (ret < 0)
723 		return 0;
724 
725 	list_for_each_entry(rentry, &resource_list, node) {
726 		if (resource_contains(rentry->res, res)) {
727 			found = 1;
728 			break;
729 		}
730 
731 	}
732 
733 	acpi_dev_free_resource_list(&resource_list);
734 	return found;
735 }
736 
737 static acpi_status acpi_res_consumer_cb(acpi_handle handle, u32 depth,
738 					 void *context, void **ret)
739 {
740 	struct resource *res = context;
741 	struct acpi_device **consumer = (struct acpi_device **) ret;
742 	struct acpi_device *adev;
743 
744 	if (acpi_bus_get_device(handle, &adev))
745 		return AE_OK;
746 
747 	if (acpi_dev_consumes_res(adev, res)) {
748 		*consumer = adev;
749 		return AE_CTRL_TERMINATE;
750 	}
751 
752 	return AE_OK;
753 }
754 
755 /**
756  * acpi_resource_consumer - Find the ACPI device that consumes @res.
757  * @res: Resource to search for.
758  *
759  * Search the current resource settings (_CRS) of every ACPI device node
760  * for @res.  If we find an ACPI device whose _CRS includes @res, return
761  * it.  Otherwise, return NULL.
762  */
763 struct acpi_device *acpi_resource_consumer(struct resource *res)
764 {
765 	struct acpi_device *consumer = NULL;
766 
767 	acpi_get_devices(NULL, acpi_res_consumer_cb, res, (void **) &consumer);
768 	return consumer;
769 }
770