xref: /openbmc/linux/drivers/acpi/osl.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  acpi_osl.c - OS-dependent functions ($Revision: 83 $)
4  *
5  *  Copyright (C) 2000       Andrew Henroid
6  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
7  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
8  *  Copyright (c) 2008 Intel Corporation
9  *   Author: Matthew Wilcox <willy@linux.intel.com>
10  */
11 
12 #define pr_fmt(fmt) "ACPI: OSL: " fmt
13 
14 #include <linux/module.h>
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/mm.h>
18 #include <linux/highmem.h>
19 #include <linux/lockdep.h>
20 #include <linux/pci.h>
21 #include <linux/interrupt.h>
22 #include <linux/kmod.h>
23 #include <linux/delay.h>
24 #include <linux/workqueue.h>
25 #include <linux/nmi.h>
26 #include <linux/acpi.h>
27 #include <linux/efi.h>
28 #include <linux/ioport.h>
29 #include <linux/list.h>
30 #include <linux/jiffies.h>
31 #include <linux/semaphore.h>
32 #include <linux/security.h>
33 
34 #include <asm/io.h>
35 #include <linux/uaccess.h>
36 #include <linux/io-64-nonatomic-lo-hi.h>
37 
38 #include "acpica/accommon.h"
39 #include "acpica/acnamesp.h"
40 #include "internal.h"
41 
42 /* Definitions for ACPI_DEBUG_PRINT() */
43 #define _COMPONENT		ACPI_OS_SERVICES
44 ACPI_MODULE_NAME("osl");
45 
46 struct acpi_os_dpc {
47 	acpi_osd_exec_callback function;
48 	void *context;
49 	struct work_struct work;
50 };
51 
52 #ifdef ENABLE_DEBUGGER
53 #include <linux/kdb.h>
54 
55 /* stuff for debugger support */
56 int acpi_in_debugger;
57 EXPORT_SYMBOL(acpi_in_debugger);
58 #endif				/*ENABLE_DEBUGGER */
59 
60 static int (*__acpi_os_prepare_sleep)(u8 sleep_state, u32 pm1a_ctrl,
61 				      u32 pm1b_ctrl);
62 static int (*__acpi_os_prepare_extended_sleep)(u8 sleep_state, u32 val_a,
63 				      u32 val_b);
64 
65 static acpi_osd_handler acpi_irq_handler;
66 static void *acpi_irq_context;
67 static struct workqueue_struct *kacpid_wq;
68 static struct workqueue_struct *kacpi_notify_wq;
69 static struct workqueue_struct *kacpi_hotplug_wq;
70 static bool acpi_os_initialized;
71 unsigned int acpi_sci_irq = INVALID_ACPI_IRQ;
72 bool acpi_permanent_mmap = false;
73 
74 /*
75  * This list of permanent mappings is for memory that may be accessed from
76  * interrupt context, where we can't do the ioremap().
77  */
78 struct acpi_ioremap {
79 	struct list_head list;
80 	void __iomem *virt;
81 	acpi_physical_address phys;
82 	acpi_size size;
83 	union {
84 		unsigned long refcount;
85 		struct rcu_work rwork;
86 	} track;
87 };
88 
89 static LIST_HEAD(acpi_ioremaps);
90 static DEFINE_MUTEX(acpi_ioremap_lock);
91 #define acpi_ioremap_lock_held() lock_is_held(&acpi_ioremap_lock.dep_map)
92 
93 static void __init acpi_request_region (struct acpi_generic_address *gas,
94 	unsigned int length, char *desc)
95 {
96 	u64 addr;
97 
98 	/* Handle possible alignment issues */
99 	memcpy(&addr, &gas->address, sizeof(addr));
100 	if (!addr || !length)
101 		return;
102 
103 	/* Resources are never freed */
104 	if (gas->space_id == ACPI_ADR_SPACE_SYSTEM_IO)
105 		request_region(addr, length, desc);
106 	else if (gas->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY)
107 		request_mem_region(addr, length, desc);
108 }
109 
110 static int __init acpi_reserve_resources(void)
111 {
112 	acpi_request_region(&acpi_gbl_FADT.xpm1a_event_block, acpi_gbl_FADT.pm1_event_length,
113 		"ACPI PM1a_EVT_BLK");
114 
115 	acpi_request_region(&acpi_gbl_FADT.xpm1b_event_block, acpi_gbl_FADT.pm1_event_length,
116 		"ACPI PM1b_EVT_BLK");
117 
118 	acpi_request_region(&acpi_gbl_FADT.xpm1a_control_block, acpi_gbl_FADT.pm1_control_length,
119 		"ACPI PM1a_CNT_BLK");
120 
121 	acpi_request_region(&acpi_gbl_FADT.xpm1b_control_block, acpi_gbl_FADT.pm1_control_length,
122 		"ACPI PM1b_CNT_BLK");
123 
124 	if (acpi_gbl_FADT.pm_timer_length == 4)
125 		acpi_request_region(&acpi_gbl_FADT.xpm_timer_block, 4, "ACPI PM_TMR");
126 
127 	acpi_request_region(&acpi_gbl_FADT.xpm2_control_block, acpi_gbl_FADT.pm2_control_length,
128 		"ACPI PM2_CNT_BLK");
129 
130 	/* Length of GPE blocks must be a non-negative multiple of 2 */
131 
132 	if (!(acpi_gbl_FADT.gpe0_block_length & 0x1))
133 		acpi_request_region(&acpi_gbl_FADT.xgpe0_block,
134 			       acpi_gbl_FADT.gpe0_block_length, "ACPI GPE0_BLK");
135 
136 	if (!(acpi_gbl_FADT.gpe1_block_length & 0x1))
137 		acpi_request_region(&acpi_gbl_FADT.xgpe1_block,
138 			       acpi_gbl_FADT.gpe1_block_length, "ACPI GPE1_BLK");
139 
140 	return 0;
141 }
142 fs_initcall_sync(acpi_reserve_resources);
143 
144 void acpi_os_printf(const char *fmt, ...)
145 {
146 	va_list args;
147 	va_start(args, fmt);
148 	acpi_os_vprintf(fmt, args);
149 	va_end(args);
150 }
151 EXPORT_SYMBOL(acpi_os_printf);
152 
153 void acpi_os_vprintf(const char *fmt, va_list args)
154 {
155 	static char buffer[512];
156 
157 	vsprintf(buffer, fmt, args);
158 
159 #ifdef ENABLE_DEBUGGER
160 	if (acpi_in_debugger) {
161 		kdb_printf("%s", buffer);
162 	} else {
163 		if (printk_get_level(buffer))
164 			printk("%s", buffer);
165 		else
166 			printk(KERN_CONT "%s", buffer);
167 	}
168 #else
169 	if (acpi_debugger_write_log(buffer) < 0) {
170 		if (printk_get_level(buffer))
171 			printk("%s", buffer);
172 		else
173 			printk(KERN_CONT "%s", buffer);
174 	}
175 #endif
176 }
177 
178 #ifdef CONFIG_KEXEC
179 static unsigned long acpi_rsdp;
180 static int __init setup_acpi_rsdp(char *arg)
181 {
182 	return kstrtoul(arg, 16, &acpi_rsdp);
183 }
184 early_param("acpi_rsdp", setup_acpi_rsdp);
185 #endif
186 
187 acpi_physical_address __init acpi_os_get_root_pointer(void)
188 {
189 	acpi_physical_address pa;
190 
191 #ifdef CONFIG_KEXEC
192 	/*
193 	 * We may have been provided with an RSDP on the command line,
194 	 * but if a malicious user has done so they may be pointing us
195 	 * at modified ACPI tables that could alter kernel behaviour -
196 	 * so, we check the lockdown status before making use of
197 	 * it. If we trust it then also stash it in an architecture
198 	 * specific location (if appropriate) so it can be carried
199 	 * over further kexec()s.
200 	 */
201 	if (acpi_rsdp && !security_locked_down(LOCKDOWN_ACPI_TABLES)) {
202 		acpi_arch_set_root_pointer(acpi_rsdp);
203 		return acpi_rsdp;
204 	}
205 #endif
206 	pa = acpi_arch_get_root_pointer();
207 	if (pa)
208 		return pa;
209 
210 	if (efi_enabled(EFI_CONFIG_TABLES)) {
211 		if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
212 			return efi.acpi20;
213 		if (efi.acpi != EFI_INVALID_TABLE_ADDR)
214 			return efi.acpi;
215 		pr_err(PREFIX "System description tables not found\n");
216 	} else if (IS_ENABLED(CONFIG_ACPI_LEGACY_TABLES_LOOKUP)) {
217 		acpi_find_root_pointer(&pa);
218 	}
219 
220 	return pa;
221 }
222 
223 /* Must be called with 'acpi_ioremap_lock' or RCU read lock held. */
224 static struct acpi_ioremap *
225 acpi_map_lookup(acpi_physical_address phys, acpi_size size)
226 {
227 	struct acpi_ioremap *map;
228 
229 	list_for_each_entry_rcu(map, &acpi_ioremaps, list, acpi_ioremap_lock_held())
230 		if (map->phys <= phys &&
231 		    phys + size <= map->phys + map->size)
232 			return map;
233 
234 	return NULL;
235 }
236 
237 /* Must be called with 'acpi_ioremap_lock' or RCU read lock held. */
238 static void __iomem *
239 acpi_map_vaddr_lookup(acpi_physical_address phys, unsigned int size)
240 {
241 	struct acpi_ioremap *map;
242 
243 	map = acpi_map_lookup(phys, size);
244 	if (map)
245 		return map->virt + (phys - map->phys);
246 
247 	return NULL;
248 }
249 
250 void __iomem *acpi_os_get_iomem(acpi_physical_address phys, unsigned int size)
251 {
252 	struct acpi_ioremap *map;
253 	void __iomem *virt = NULL;
254 
255 	mutex_lock(&acpi_ioremap_lock);
256 	map = acpi_map_lookup(phys, size);
257 	if (map) {
258 		virt = map->virt + (phys - map->phys);
259 		map->track.refcount++;
260 	}
261 	mutex_unlock(&acpi_ioremap_lock);
262 	return virt;
263 }
264 EXPORT_SYMBOL_GPL(acpi_os_get_iomem);
265 
266 /* Must be called with 'acpi_ioremap_lock' or RCU read lock held. */
267 static struct acpi_ioremap *
268 acpi_map_lookup_virt(void __iomem *virt, acpi_size size)
269 {
270 	struct acpi_ioremap *map;
271 
272 	list_for_each_entry_rcu(map, &acpi_ioremaps, list, acpi_ioremap_lock_held())
273 		if (map->virt <= virt &&
274 		    virt + size <= map->virt + map->size)
275 			return map;
276 
277 	return NULL;
278 }
279 
280 #if defined(CONFIG_IA64) || defined(CONFIG_ARM64)
281 /* ioremap will take care of cache attributes */
282 #define should_use_kmap(pfn)   0
283 #else
284 #define should_use_kmap(pfn)   page_is_ram(pfn)
285 #endif
286 
287 static void __iomem *acpi_map(acpi_physical_address pg_off, unsigned long pg_sz)
288 {
289 	unsigned long pfn;
290 
291 	pfn = pg_off >> PAGE_SHIFT;
292 	if (should_use_kmap(pfn)) {
293 		if (pg_sz > PAGE_SIZE)
294 			return NULL;
295 		return (void __iomem __force *)kmap(pfn_to_page(pfn));
296 	} else
297 		return acpi_os_ioremap(pg_off, pg_sz);
298 }
299 
300 static void acpi_unmap(acpi_physical_address pg_off, void __iomem *vaddr)
301 {
302 	unsigned long pfn;
303 
304 	pfn = pg_off >> PAGE_SHIFT;
305 	if (should_use_kmap(pfn))
306 		kunmap(pfn_to_page(pfn));
307 	else
308 		iounmap(vaddr);
309 }
310 
311 /**
312  * acpi_os_map_iomem - Get a virtual address for a given physical address range.
313  * @phys: Start of the physical address range to map.
314  * @size: Size of the physical address range to map.
315  *
316  * Look up the given physical address range in the list of existing ACPI memory
317  * mappings.  If found, get a reference to it and return a pointer to it (its
318  * virtual address).  If not found, map it, add it to that list and return a
319  * pointer to it.
320  *
321  * During early init (when acpi_permanent_mmap has not been set yet) this
322  * routine simply calls __acpi_map_table() to get the job done.
323  */
324 void __iomem __ref
325 *acpi_os_map_iomem(acpi_physical_address phys, acpi_size size)
326 {
327 	struct acpi_ioremap *map;
328 	void __iomem *virt;
329 	acpi_physical_address pg_off;
330 	acpi_size pg_sz;
331 
332 	if (phys > ULONG_MAX) {
333 		pr_err("Cannot map memory that high: 0x%llx\n", phys);
334 		return NULL;
335 	}
336 
337 	if (!acpi_permanent_mmap)
338 		return __acpi_map_table((unsigned long)phys, size);
339 
340 	mutex_lock(&acpi_ioremap_lock);
341 	/* Check if there's a suitable mapping already. */
342 	map = acpi_map_lookup(phys, size);
343 	if (map) {
344 		map->track.refcount++;
345 		goto out;
346 	}
347 
348 	map = kzalloc(sizeof(*map), GFP_KERNEL);
349 	if (!map) {
350 		mutex_unlock(&acpi_ioremap_lock);
351 		return NULL;
352 	}
353 
354 	pg_off = round_down(phys, PAGE_SIZE);
355 	pg_sz = round_up(phys + size, PAGE_SIZE) - pg_off;
356 	virt = acpi_map(phys, size);
357 	if (!virt) {
358 		mutex_unlock(&acpi_ioremap_lock);
359 		kfree(map);
360 		return NULL;
361 	}
362 
363 	INIT_LIST_HEAD(&map->list);
364 	map->virt = (void __iomem __force *)((unsigned long)virt & PAGE_MASK);
365 	map->phys = pg_off;
366 	map->size = pg_sz;
367 	map->track.refcount = 1;
368 
369 	list_add_tail_rcu(&map->list, &acpi_ioremaps);
370 
371 out:
372 	mutex_unlock(&acpi_ioremap_lock);
373 	return map->virt + (phys - map->phys);
374 }
375 EXPORT_SYMBOL_GPL(acpi_os_map_iomem);
376 
377 void *__ref acpi_os_map_memory(acpi_physical_address phys, acpi_size size)
378 {
379 	return (void *)acpi_os_map_iomem(phys, size);
380 }
381 EXPORT_SYMBOL_GPL(acpi_os_map_memory);
382 
383 static void acpi_os_map_remove(struct work_struct *work)
384 {
385 	struct acpi_ioremap *map = container_of(to_rcu_work(work),
386 						struct acpi_ioremap,
387 						track.rwork);
388 
389 	acpi_unmap(map->phys, map->virt);
390 	kfree(map);
391 }
392 
393 /* Must be called with mutex_lock(&acpi_ioremap_lock) */
394 static void acpi_os_drop_map_ref(struct acpi_ioremap *map)
395 {
396 	if (--map->track.refcount)
397 		return;
398 
399 	list_del_rcu(&map->list);
400 
401 	INIT_RCU_WORK(&map->track.rwork, acpi_os_map_remove);
402 	queue_rcu_work(system_wq, &map->track.rwork);
403 }
404 
405 /**
406  * acpi_os_unmap_iomem - Drop a memory mapping reference.
407  * @virt: Start of the address range to drop a reference to.
408  * @size: Size of the address range to drop a reference to.
409  *
410  * Look up the given virtual address range in the list of existing ACPI memory
411  * mappings, drop a reference to it and if there are no more active references
412  * to it, queue it up for later removal.
413  *
414  * During early init (when acpi_permanent_mmap has not been set yet) this
415  * routine simply calls __acpi_unmap_table() to get the job done.  Since
416  * __acpi_unmap_table() is an __init function, the __ref annotation is needed
417  * here.
418  */
419 void __ref acpi_os_unmap_iomem(void __iomem *virt, acpi_size size)
420 {
421 	struct acpi_ioremap *map;
422 
423 	if (!acpi_permanent_mmap) {
424 		__acpi_unmap_table(virt, size);
425 		return;
426 	}
427 
428 	mutex_lock(&acpi_ioremap_lock);
429 
430 	map = acpi_map_lookup_virt(virt, size);
431 	if (!map) {
432 		mutex_unlock(&acpi_ioremap_lock);
433 		WARN(true, PREFIX "%s: bad address %p\n", __func__, virt);
434 		return;
435 	}
436 	acpi_os_drop_map_ref(map);
437 
438 	mutex_unlock(&acpi_ioremap_lock);
439 }
440 EXPORT_SYMBOL_GPL(acpi_os_unmap_iomem);
441 
442 /**
443  * acpi_os_unmap_memory - Drop a memory mapping reference.
444  * @virt: Start of the address range to drop a reference to.
445  * @size: Size of the address range to drop a reference to.
446  */
447 void __ref acpi_os_unmap_memory(void *virt, acpi_size size)
448 {
449 	acpi_os_unmap_iomem((void __iomem *)virt, size);
450 }
451 EXPORT_SYMBOL_GPL(acpi_os_unmap_memory);
452 
453 void __iomem *acpi_os_map_generic_address(struct acpi_generic_address *gas)
454 {
455 	u64 addr;
456 
457 	if (gas->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY)
458 		return NULL;
459 
460 	/* Handle possible alignment issues */
461 	memcpy(&addr, &gas->address, sizeof(addr));
462 	if (!addr || !gas->bit_width)
463 		return NULL;
464 
465 	return acpi_os_map_iomem(addr, gas->bit_width / 8);
466 }
467 EXPORT_SYMBOL(acpi_os_map_generic_address);
468 
469 void acpi_os_unmap_generic_address(struct acpi_generic_address *gas)
470 {
471 	u64 addr;
472 	struct acpi_ioremap *map;
473 
474 	if (gas->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY)
475 		return;
476 
477 	/* Handle possible alignment issues */
478 	memcpy(&addr, &gas->address, sizeof(addr));
479 	if (!addr || !gas->bit_width)
480 		return;
481 
482 	mutex_lock(&acpi_ioremap_lock);
483 
484 	map = acpi_map_lookup(addr, gas->bit_width / 8);
485 	if (!map) {
486 		mutex_unlock(&acpi_ioremap_lock);
487 		return;
488 	}
489 	acpi_os_drop_map_ref(map);
490 
491 	mutex_unlock(&acpi_ioremap_lock);
492 }
493 EXPORT_SYMBOL(acpi_os_unmap_generic_address);
494 
495 #ifdef ACPI_FUTURE_USAGE
496 acpi_status
497 acpi_os_get_physical_address(void *virt, acpi_physical_address * phys)
498 {
499 	if (!phys || !virt)
500 		return AE_BAD_PARAMETER;
501 
502 	*phys = virt_to_phys(virt);
503 
504 	return AE_OK;
505 }
506 #endif
507 
508 #ifdef CONFIG_ACPI_REV_OVERRIDE_POSSIBLE
509 static bool acpi_rev_override;
510 
511 int __init acpi_rev_override_setup(char *str)
512 {
513 	acpi_rev_override = true;
514 	return 1;
515 }
516 __setup("acpi_rev_override", acpi_rev_override_setup);
517 #else
518 #define acpi_rev_override	false
519 #endif
520 
521 #define ACPI_MAX_OVERRIDE_LEN 100
522 
523 static char acpi_os_name[ACPI_MAX_OVERRIDE_LEN];
524 
525 acpi_status
526 acpi_os_predefined_override(const struct acpi_predefined_names *init_val,
527 			    acpi_string *new_val)
528 {
529 	if (!init_val || !new_val)
530 		return AE_BAD_PARAMETER;
531 
532 	*new_val = NULL;
533 	if (!memcmp(init_val->name, "_OS_", 4) && strlen(acpi_os_name)) {
534 		pr_info("Overriding _OS definition to '%s'\n", acpi_os_name);
535 		*new_val = acpi_os_name;
536 	}
537 
538 	if (!memcmp(init_val->name, "_REV", 4) && acpi_rev_override) {
539 		pr_info("Overriding _REV return value to 5\n");
540 		*new_val = (char *)5;
541 	}
542 
543 	return AE_OK;
544 }
545 
546 static irqreturn_t acpi_irq(int irq, void *dev_id)
547 {
548 	u32 handled;
549 
550 	handled = (*acpi_irq_handler) (acpi_irq_context);
551 
552 	if (handled) {
553 		acpi_irq_handled++;
554 		return IRQ_HANDLED;
555 	} else {
556 		acpi_irq_not_handled++;
557 		return IRQ_NONE;
558 	}
559 }
560 
561 acpi_status
562 acpi_os_install_interrupt_handler(u32 gsi, acpi_osd_handler handler,
563 				  void *context)
564 {
565 	unsigned int irq;
566 
567 	acpi_irq_stats_init();
568 
569 	/*
570 	 * ACPI interrupts different from the SCI in our copy of the FADT are
571 	 * not supported.
572 	 */
573 	if (gsi != acpi_gbl_FADT.sci_interrupt)
574 		return AE_BAD_PARAMETER;
575 
576 	if (acpi_irq_handler)
577 		return AE_ALREADY_ACQUIRED;
578 
579 	if (acpi_gsi_to_irq(gsi, &irq) < 0) {
580 		pr_err("SCI (ACPI GSI %d) not registered\n", gsi);
581 		return AE_OK;
582 	}
583 
584 	acpi_irq_handler = handler;
585 	acpi_irq_context = context;
586 	if (request_irq(irq, acpi_irq, IRQF_SHARED, "acpi", acpi_irq)) {
587 		pr_err("SCI (IRQ%d) allocation failed\n", irq);
588 		acpi_irq_handler = NULL;
589 		return AE_NOT_ACQUIRED;
590 	}
591 	acpi_sci_irq = irq;
592 
593 	return AE_OK;
594 }
595 
596 acpi_status acpi_os_remove_interrupt_handler(u32 gsi, acpi_osd_handler handler)
597 {
598 	if (gsi != acpi_gbl_FADT.sci_interrupt || !acpi_sci_irq_valid())
599 		return AE_BAD_PARAMETER;
600 
601 	free_irq(acpi_sci_irq, acpi_irq);
602 	acpi_irq_handler = NULL;
603 	acpi_sci_irq = INVALID_ACPI_IRQ;
604 
605 	return AE_OK;
606 }
607 
608 /*
609  * Running in interpreter thread context, safe to sleep
610  */
611 
612 void acpi_os_sleep(u64 ms)
613 {
614 	msleep(ms);
615 }
616 
617 void acpi_os_stall(u32 us)
618 {
619 	while (us) {
620 		u32 delay = 1000;
621 
622 		if (delay > us)
623 			delay = us;
624 		udelay(delay);
625 		touch_nmi_watchdog();
626 		us -= delay;
627 	}
628 }
629 
630 /*
631  * Support ACPI 3.0 AML Timer operand. Returns a 64-bit free-running,
632  * monotonically increasing timer with 100ns granularity. Do not use
633  * ktime_get() to implement this function because this function may get
634  * called after timekeeping has been suspended. Note: calling this function
635  * after timekeeping has been suspended may lead to unexpected results
636  * because when timekeeping is suspended the jiffies counter is not
637  * incremented. See also timekeeping_suspend().
638  */
639 u64 acpi_os_get_timer(void)
640 {
641 	return (get_jiffies_64() - INITIAL_JIFFIES) *
642 		(ACPI_100NSEC_PER_SEC / HZ);
643 }
644 
645 acpi_status acpi_os_read_port(acpi_io_address port, u32 * value, u32 width)
646 {
647 	u32 dummy;
648 
649 	if (!value)
650 		value = &dummy;
651 
652 	*value = 0;
653 	if (width <= 8) {
654 		*(u8 *) value = inb(port);
655 	} else if (width <= 16) {
656 		*(u16 *) value = inw(port);
657 	} else if (width <= 32) {
658 		*(u32 *) value = inl(port);
659 	} else {
660 		BUG();
661 	}
662 
663 	return AE_OK;
664 }
665 
666 EXPORT_SYMBOL(acpi_os_read_port);
667 
668 acpi_status acpi_os_write_port(acpi_io_address port, u32 value, u32 width)
669 {
670 	if (width <= 8) {
671 		outb(value, port);
672 	} else if (width <= 16) {
673 		outw(value, port);
674 	} else if (width <= 32) {
675 		outl(value, port);
676 	} else {
677 		BUG();
678 	}
679 
680 	return AE_OK;
681 }
682 
683 EXPORT_SYMBOL(acpi_os_write_port);
684 
685 int acpi_os_read_iomem(void __iomem *virt_addr, u64 *value, u32 width)
686 {
687 
688 	switch (width) {
689 	case 8:
690 		*(u8 *) value = readb(virt_addr);
691 		break;
692 	case 16:
693 		*(u16 *) value = readw(virt_addr);
694 		break;
695 	case 32:
696 		*(u32 *) value = readl(virt_addr);
697 		break;
698 	case 64:
699 		*(u64 *) value = readq(virt_addr);
700 		break;
701 	default:
702 		return -EINVAL;
703 	}
704 
705 	return 0;
706 }
707 
708 acpi_status
709 acpi_os_read_memory(acpi_physical_address phys_addr, u64 *value, u32 width)
710 {
711 	void __iomem *virt_addr;
712 	unsigned int size = width / 8;
713 	bool unmap = false;
714 	u64 dummy;
715 	int error;
716 
717 	rcu_read_lock();
718 	virt_addr = acpi_map_vaddr_lookup(phys_addr, size);
719 	if (!virt_addr) {
720 		rcu_read_unlock();
721 		virt_addr = acpi_os_ioremap(phys_addr, size);
722 		if (!virt_addr)
723 			return AE_BAD_ADDRESS;
724 		unmap = true;
725 	}
726 
727 	if (!value)
728 		value = &dummy;
729 
730 	error = acpi_os_read_iomem(virt_addr, value, width);
731 	BUG_ON(error);
732 
733 	if (unmap)
734 		iounmap(virt_addr);
735 	else
736 		rcu_read_unlock();
737 
738 	return AE_OK;
739 }
740 
741 acpi_status
742 acpi_os_write_memory(acpi_physical_address phys_addr, u64 value, u32 width)
743 {
744 	void __iomem *virt_addr;
745 	unsigned int size = width / 8;
746 	bool unmap = false;
747 
748 	rcu_read_lock();
749 	virt_addr = acpi_map_vaddr_lookup(phys_addr, size);
750 	if (!virt_addr) {
751 		rcu_read_unlock();
752 		virt_addr = acpi_os_ioremap(phys_addr, size);
753 		if (!virt_addr)
754 			return AE_BAD_ADDRESS;
755 		unmap = true;
756 	}
757 
758 	switch (width) {
759 	case 8:
760 		writeb(value, virt_addr);
761 		break;
762 	case 16:
763 		writew(value, virt_addr);
764 		break;
765 	case 32:
766 		writel(value, virt_addr);
767 		break;
768 	case 64:
769 		writeq(value, virt_addr);
770 		break;
771 	default:
772 		BUG();
773 	}
774 
775 	if (unmap)
776 		iounmap(virt_addr);
777 	else
778 		rcu_read_unlock();
779 
780 	return AE_OK;
781 }
782 
783 #ifdef CONFIG_PCI
784 acpi_status
785 acpi_os_read_pci_configuration(struct acpi_pci_id * pci_id, u32 reg,
786 			       u64 *value, u32 width)
787 {
788 	int result, size;
789 	u32 value32;
790 
791 	if (!value)
792 		return AE_BAD_PARAMETER;
793 
794 	switch (width) {
795 	case 8:
796 		size = 1;
797 		break;
798 	case 16:
799 		size = 2;
800 		break;
801 	case 32:
802 		size = 4;
803 		break;
804 	default:
805 		return AE_ERROR;
806 	}
807 
808 	result = raw_pci_read(pci_id->segment, pci_id->bus,
809 				PCI_DEVFN(pci_id->device, pci_id->function),
810 				reg, size, &value32);
811 	*value = value32;
812 
813 	return (result ? AE_ERROR : AE_OK);
814 }
815 
816 acpi_status
817 acpi_os_write_pci_configuration(struct acpi_pci_id * pci_id, u32 reg,
818 				u64 value, u32 width)
819 {
820 	int result, size;
821 
822 	switch (width) {
823 	case 8:
824 		size = 1;
825 		break;
826 	case 16:
827 		size = 2;
828 		break;
829 	case 32:
830 		size = 4;
831 		break;
832 	default:
833 		return AE_ERROR;
834 	}
835 
836 	result = raw_pci_write(pci_id->segment, pci_id->bus,
837 				PCI_DEVFN(pci_id->device, pci_id->function),
838 				reg, size, value);
839 
840 	return (result ? AE_ERROR : AE_OK);
841 }
842 #endif
843 
844 static void acpi_os_execute_deferred(struct work_struct *work)
845 {
846 	struct acpi_os_dpc *dpc = container_of(work, struct acpi_os_dpc, work);
847 
848 	dpc->function(dpc->context);
849 	kfree(dpc);
850 }
851 
852 #ifdef CONFIG_ACPI_DEBUGGER
853 static struct acpi_debugger acpi_debugger;
854 static bool acpi_debugger_initialized;
855 
856 int acpi_register_debugger(struct module *owner,
857 			   const struct acpi_debugger_ops *ops)
858 {
859 	int ret = 0;
860 
861 	mutex_lock(&acpi_debugger.lock);
862 	if (acpi_debugger.ops) {
863 		ret = -EBUSY;
864 		goto err_lock;
865 	}
866 
867 	acpi_debugger.owner = owner;
868 	acpi_debugger.ops = ops;
869 
870 err_lock:
871 	mutex_unlock(&acpi_debugger.lock);
872 	return ret;
873 }
874 EXPORT_SYMBOL(acpi_register_debugger);
875 
876 void acpi_unregister_debugger(const struct acpi_debugger_ops *ops)
877 {
878 	mutex_lock(&acpi_debugger.lock);
879 	if (ops == acpi_debugger.ops) {
880 		acpi_debugger.ops = NULL;
881 		acpi_debugger.owner = NULL;
882 	}
883 	mutex_unlock(&acpi_debugger.lock);
884 }
885 EXPORT_SYMBOL(acpi_unregister_debugger);
886 
887 int acpi_debugger_create_thread(acpi_osd_exec_callback function, void *context)
888 {
889 	int ret;
890 	int (*func)(acpi_osd_exec_callback, void *);
891 	struct module *owner;
892 
893 	if (!acpi_debugger_initialized)
894 		return -ENODEV;
895 	mutex_lock(&acpi_debugger.lock);
896 	if (!acpi_debugger.ops) {
897 		ret = -ENODEV;
898 		goto err_lock;
899 	}
900 	if (!try_module_get(acpi_debugger.owner)) {
901 		ret = -ENODEV;
902 		goto err_lock;
903 	}
904 	func = acpi_debugger.ops->create_thread;
905 	owner = acpi_debugger.owner;
906 	mutex_unlock(&acpi_debugger.lock);
907 
908 	ret = func(function, context);
909 
910 	mutex_lock(&acpi_debugger.lock);
911 	module_put(owner);
912 err_lock:
913 	mutex_unlock(&acpi_debugger.lock);
914 	return ret;
915 }
916 
917 ssize_t acpi_debugger_write_log(const char *msg)
918 {
919 	ssize_t ret;
920 	ssize_t (*func)(const char *);
921 	struct module *owner;
922 
923 	if (!acpi_debugger_initialized)
924 		return -ENODEV;
925 	mutex_lock(&acpi_debugger.lock);
926 	if (!acpi_debugger.ops) {
927 		ret = -ENODEV;
928 		goto err_lock;
929 	}
930 	if (!try_module_get(acpi_debugger.owner)) {
931 		ret = -ENODEV;
932 		goto err_lock;
933 	}
934 	func = acpi_debugger.ops->write_log;
935 	owner = acpi_debugger.owner;
936 	mutex_unlock(&acpi_debugger.lock);
937 
938 	ret = func(msg);
939 
940 	mutex_lock(&acpi_debugger.lock);
941 	module_put(owner);
942 err_lock:
943 	mutex_unlock(&acpi_debugger.lock);
944 	return ret;
945 }
946 
947 ssize_t acpi_debugger_read_cmd(char *buffer, size_t buffer_length)
948 {
949 	ssize_t ret;
950 	ssize_t (*func)(char *, size_t);
951 	struct module *owner;
952 
953 	if (!acpi_debugger_initialized)
954 		return -ENODEV;
955 	mutex_lock(&acpi_debugger.lock);
956 	if (!acpi_debugger.ops) {
957 		ret = -ENODEV;
958 		goto err_lock;
959 	}
960 	if (!try_module_get(acpi_debugger.owner)) {
961 		ret = -ENODEV;
962 		goto err_lock;
963 	}
964 	func = acpi_debugger.ops->read_cmd;
965 	owner = acpi_debugger.owner;
966 	mutex_unlock(&acpi_debugger.lock);
967 
968 	ret = func(buffer, buffer_length);
969 
970 	mutex_lock(&acpi_debugger.lock);
971 	module_put(owner);
972 err_lock:
973 	mutex_unlock(&acpi_debugger.lock);
974 	return ret;
975 }
976 
977 int acpi_debugger_wait_command_ready(void)
978 {
979 	int ret;
980 	int (*func)(bool, char *, size_t);
981 	struct module *owner;
982 
983 	if (!acpi_debugger_initialized)
984 		return -ENODEV;
985 	mutex_lock(&acpi_debugger.lock);
986 	if (!acpi_debugger.ops) {
987 		ret = -ENODEV;
988 		goto err_lock;
989 	}
990 	if (!try_module_get(acpi_debugger.owner)) {
991 		ret = -ENODEV;
992 		goto err_lock;
993 	}
994 	func = acpi_debugger.ops->wait_command_ready;
995 	owner = acpi_debugger.owner;
996 	mutex_unlock(&acpi_debugger.lock);
997 
998 	ret = func(acpi_gbl_method_executing,
999 		   acpi_gbl_db_line_buf, ACPI_DB_LINE_BUFFER_SIZE);
1000 
1001 	mutex_lock(&acpi_debugger.lock);
1002 	module_put(owner);
1003 err_lock:
1004 	mutex_unlock(&acpi_debugger.lock);
1005 	return ret;
1006 }
1007 
1008 int acpi_debugger_notify_command_complete(void)
1009 {
1010 	int ret;
1011 	int (*func)(void);
1012 	struct module *owner;
1013 
1014 	if (!acpi_debugger_initialized)
1015 		return -ENODEV;
1016 	mutex_lock(&acpi_debugger.lock);
1017 	if (!acpi_debugger.ops) {
1018 		ret = -ENODEV;
1019 		goto err_lock;
1020 	}
1021 	if (!try_module_get(acpi_debugger.owner)) {
1022 		ret = -ENODEV;
1023 		goto err_lock;
1024 	}
1025 	func = acpi_debugger.ops->notify_command_complete;
1026 	owner = acpi_debugger.owner;
1027 	mutex_unlock(&acpi_debugger.lock);
1028 
1029 	ret = func();
1030 
1031 	mutex_lock(&acpi_debugger.lock);
1032 	module_put(owner);
1033 err_lock:
1034 	mutex_unlock(&acpi_debugger.lock);
1035 	return ret;
1036 }
1037 
1038 int __init acpi_debugger_init(void)
1039 {
1040 	mutex_init(&acpi_debugger.lock);
1041 	acpi_debugger_initialized = true;
1042 	return 0;
1043 }
1044 #endif
1045 
1046 /*******************************************************************************
1047  *
1048  * FUNCTION:    acpi_os_execute
1049  *
1050  * PARAMETERS:  Type               - Type of the callback
1051  *              Function           - Function to be executed
1052  *              Context            - Function parameters
1053  *
1054  * RETURN:      Status
1055  *
1056  * DESCRIPTION: Depending on type, either queues function for deferred execution or
1057  *              immediately executes function on a separate thread.
1058  *
1059  ******************************************************************************/
1060 
1061 acpi_status acpi_os_execute(acpi_execute_type type,
1062 			    acpi_osd_exec_callback function, void *context)
1063 {
1064 	acpi_status status = AE_OK;
1065 	struct acpi_os_dpc *dpc;
1066 	struct workqueue_struct *queue;
1067 	int ret;
1068 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
1069 			  "Scheduling function [%p(%p)] for deferred execution.\n",
1070 			  function, context));
1071 
1072 	if (type == OSL_DEBUGGER_MAIN_THREAD) {
1073 		ret = acpi_debugger_create_thread(function, context);
1074 		if (ret) {
1075 			pr_err("Kernel thread creation failed\n");
1076 			status = AE_ERROR;
1077 		}
1078 		goto out_thread;
1079 	}
1080 
1081 	/*
1082 	 * Allocate/initialize DPC structure.  Note that this memory will be
1083 	 * freed by the callee.  The kernel handles the work_struct list  in a
1084 	 * way that allows us to also free its memory inside the callee.
1085 	 * Because we may want to schedule several tasks with different
1086 	 * parameters we can't use the approach some kernel code uses of
1087 	 * having a static work_struct.
1088 	 */
1089 
1090 	dpc = kzalloc(sizeof(struct acpi_os_dpc), GFP_ATOMIC);
1091 	if (!dpc)
1092 		return AE_NO_MEMORY;
1093 
1094 	dpc->function = function;
1095 	dpc->context = context;
1096 
1097 	/*
1098 	 * To prevent lockdep from complaining unnecessarily, make sure that
1099 	 * there is a different static lockdep key for each workqueue by using
1100 	 * INIT_WORK() for each of them separately.
1101 	 */
1102 	if (type == OSL_NOTIFY_HANDLER) {
1103 		queue = kacpi_notify_wq;
1104 		INIT_WORK(&dpc->work, acpi_os_execute_deferred);
1105 	} else if (type == OSL_GPE_HANDLER) {
1106 		queue = kacpid_wq;
1107 		INIT_WORK(&dpc->work, acpi_os_execute_deferred);
1108 	} else {
1109 		pr_err("Unsupported os_execute type %d.\n", type);
1110 		status = AE_ERROR;
1111 	}
1112 
1113 	if (ACPI_FAILURE(status))
1114 		goto err_workqueue;
1115 
1116 	/*
1117 	 * On some machines, a software-initiated SMI causes corruption unless
1118 	 * the SMI runs on CPU 0.  An SMI can be initiated by any AML, but
1119 	 * typically it's done in GPE-related methods that are run via
1120 	 * workqueues, so we can avoid the known corruption cases by always
1121 	 * queueing on CPU 0.
1122 	 */
1123 	ret = queue_work_on(0, queue, &dpc->work);
1124 	if (!ret) {
1125 		pr_err("Unable to queue work\n");
1126 		status = AE_ERROR;
1127 	}
1128 err_workqueue:
1129 	if (ACPI_FAILURE(status))
1130 		kfree(dpc);
1131 out_thread:
1132 	return status;
1133 }
1134 EXPORT_SYMBOL(acpi_os_execute);
1135 
1136 void acpi_os_wait_events_complete(void)
1137 {
1138 	/*
1139 	 * Make sure the GPE handler or the fixed event handler is not used
1140 	 * on another CPU after removal.
1141 	 */
1142 	if (acpi_sci_irq_valid())
1143 		synchronize_hardirq(acpi_sci_irq);
1144 	flush_workqueue(kacpid_wq);
1145 	flush_workqueue(kacpi_notify_wq);
1146 }
1147 EXPORT_SYMBOL(acpi_os_wait_events_complete);
1148 
1149 struct acpi_hp_work {
1150 	struct work_struct work;
1151 	struct acpi_device *adev;
1152 	u32 src;
1153 };
1154 
1155 static void acpi_hotplug_work_fn(struct work_struct *work)
1156 {
1157 	struct acpi_hp_work *hpw = container_of(work, struct acpi_hp_work, work);
1158 
1159 	acpi_os_wait_events_complete();
1160 	acpi_device_hotplug(hpw->adev, hpw->src);
1161 	kfree(hpw);
1162 }
1163 
1164 acpi_status acpi_hotplug_schedule(struct acpi_device *adev, u32 src)
1165 {
1166 	struct acpi_hp_work *hpw;
1167 
1168 	acpi_handle_debug(adev->handle,
1169 			  "Scheduling hotplug event %u for deferred handling\n",
1170 			   src);
1171 
1172 	hpw = kmalloc(sizeof(*hpw), GFP_KERNEL);
1173 	if (!hpw)
1174 		return AE_NO_MEMORY;
1175 
1176 	INIT_WORK(&hpw->work, acpi_hotplug_work_fn);
1177 	hpw->adev = adev;
1178 	hpw->src = src;
1179 	/*
1180 	 * We can't run hotplug code in kacpid_wq/kacpid_notify_wq etc., because
1181 	 * the hotplug code may call driver .remove() functions, which may
1182 	 * invoke flush_scheduled_work()/acpi_os_wait_events_complete() to flush
1183 	 * these workqueues.
1184 	 */
1185 	if (!queue_work(kacpi_hotplug_wq, &hpw->work)) {
1186 		kfree(hpw);
1187 		return AE_ERROR;
1188 	}
1189 	return AE_OK;
1190 }
1191 
1192 bool acpi_queue_hotplug_work(struct work_struct *work)
1193 {
1194 	return queue_work(kacpi_hotplug_wq, work);
1195 }
1196 
1197 acpi_status
1198 acpi_os_create_semaphore(u32 max_units, u32 initial_units, acpi_handle * handle)
1199 {
1200 	struct semaphore *sem = NULL;
1201 
1202 	sem = acpi_os_allocate_zeroed(sizeof(struct semaphore));
1203 	if (!sem)
1204 		return AE_NO_MEMORY;
1205 
1206 	sema_init(sem, initial_units);
1207 
1208 	*handle = (acpi_handle *) sem;
1209 
1210 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Creating semaphore[%p|%d].\n",
1211 			  *handle, initial_units));
1212 
1213 	return AE_OK;
1214 }
1215 
1216 /*
1217  * TODO: A better way to delete semaphores?  Linux doesn't have a
1218  * 'delete_semaphore()' function -- may result in an invalid
1219  * pointer dereference for non-synchronized consumers.	Should
1220  * we at least check for blocked threads and signal/cancel them?
1221  */
1222 
1223 acpi_status acpi_os_delete_semaphore(acpi_handle handle)
1224 {
1225 	struct semaphore *sem = (struct semaphore *)handle;
1226 
1227 	if (!sem)
1228 		return AE_BAD_PARAMETER;
1229 
1230 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Deleting semaphore[%p].\n", handle));
1231 
1232 	BUG_ON(!list_empty(&sem->wait_list));
1233 	kfree(sem);
1234 	sem = NULL;
1235 
1236 	return AE_OK;
1237 }
1238 
1239 /*
1240  * TODO: Support for units > 1?
1241  */
1242 acpi_status acpi_os_wait_semaphore(acpi_handle handle, u32 units, u16 timeout)
1243 {
1244 	acpi_status status = AE_OK;
1245 	struct semaphore *sem = (struct semaphore *)handle;
1246 	long jiffies;
1247 	int ret = 0;
1248 
1249 	if (!acpi_os_initialized)
1250 		return AE_OK;
1251 
1252 	if (!sem || (units < 1))
1253 		return AE_BAD_PARAMETER;
1254 
1255 	if (units > 1)
1256 		return AE_SUPPORT;
1257 
1258 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Waiting for semaphore[%p|%d|%d]\n",
1259 			  handle, units, timeout));
1260 
1261 	if (timeout == ACPI_WAIT_FOREVER)
1262 		jiffies = MAX_SCHEDULE_TIMEOUT;
1263 	else
1264 		jiffies = msecs_to_jiffies(timeout);
1265 
1266 	ret = down_timeout(sem, jiffies);
1267 	if (ret)
1268 		status = AE_TIME;
1269 
1270 	if (ACPI_FAILURE(status)) {
1271 		ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
1272 				  "Failed to acquire semaphore[%p|%d|%d], %s",
1273 				  handle, units, timeout,
1274 				  acpi_format_exception(status)));
1275 	} else {
1276 		ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
1277 				  "Acquired semaphore[%p|%d|%d]", handle,
1278 				  units, timeout));
1279 	}
1280 
1281 	return status;
1282 }
1283 
1284 /*
1285  * TODO: Support for units > 1?
1286  */
1287 acpi_status acpi_os_signal_semaphore(acpi_handle handle, u32 units)
1288 {
1289 	struct semaphore *sem = (struct semaphore *)handle;
1290 
1291 	if (!acpi_os_initialized)
1292 		return AE_OK;
1293 
1294 	if (!sem || (units < 1))
1295 		return AE_BAD_PARAMETER;
1296 
1297 	if (units > 1)
1298 		return AE_SUPPORT;
1299 
1300 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Signaling semaphore[%p|%d]\n", handle,
1301 			  units));
1302 
1303 	up(sem);
1304 
1305 	return AE_OK;
1306 }
1307 
1308 acpi_status acpi_os_get_line(char *buffer, u32 buffer_length, u32 *bytes_read)
1309 {
1310 #ifdef ENABLE_DEBUGGER
1311 	if (acpi_in_debugger) {
1312 		u32 chars;
1313 
1314 		kdb_read(buffer, buffer_length);
1315 
1316 		/* remove the CR kdb includes */
1317 		chars = strlen(buffer) - 1;
1318 		buffer[chars] = '\0';
1319 	}
1320 #else
1321 	int ret;
1322 
1323 	ret = acpi_debugger_read_cmd(buffer, buffer_length);
1324 	if (ret < 0)
1325 		return AE_ERROR;
1326 	if (bytes_read)
1327 		*bytes_read = ret;
1328 #endif
1329 
1330 	return AE_OK;
1331 }
1332 EXPORT_SYMBOL(acpi_os_get_line);
1333 
1334 acpi_status acpi_os_wait_command_ready(void)
1335 {
1336 	int ret;
1337 
1338 	ret = acpi_debugger_wait_command_ready();
1339 	if (ret < 0)
1340 		return AE_ERROR;
1341 	return AE_OK;
1342 }
1343 
1344 acpi_status acpi_os_notify_command_complete(void)
1345 {
1346 	int ret;
1347 
1348 	ret = acpi_debugger_notify_command_complete();
1349 	if (ret < 0)
1350 		return AE_ERROR;
1351 	return AE_OK;
1352 }
1353 
1354 acpi_status acpi_os_signal(u32 function, void *info)
1355 {
1356 	switch (function) {
1357 	case ACPI_SIGNAL_FATAL:
1358 		pr_err("Fatal opcode executed\n");
1359 		break;
1360 	case ACPI_SIGNAL_BREAKPOINT:
1361 		/*
1362 		 * AML Breakpoint
1363 		 * ACPI spec. says to treat it as a NOP unless
1364 		 * you are debugging.  So if/when we integrate
1365 		 * AML debugger into the kernel debugger its
1366 		 * hook will go here.  But until then it is
1367 		 * not useful to print anything on breakpoints.
1368 		 */
1369 		break;
1370 	default:
1371 		break;
1372 	}
1373 
1374 	return AE_OK;
1375 }
1376 
1377 static int __init acpi_os_name_setup(char *str)
1378 {
1379 	char *p = acpi_os_name;
1380 	int count = ACPI_MAX_OVERRIDE_LEN - 1;
1381 
1382 	if (!str || !*str)
1383 		return 0;
1384 
1385 	for (; count-- && *str; str++) {
1386 		if (isalnum(*str) || *str == ' ' || *str == ':')
1387 			*p++ = *str;
1388 		else if (*str == '\'' || *str == '"')
1389 			continue;
1390 		else
1391 			break;
1392 	}
1393 	*p = 0;
1394 
1395 	return 1;
1396 
1397 }
1398 
1399 __setup("acpi_os_name=", acpi_os_name_setup);
1400 
1401 /*
1402  * Disable the auto-serialization of named objects creation methods.
1403  *
1404  * This feature is enabled by default.  It marks the AML control methods
1405  * that contain the opcodes to create named objects as "Serialized".
1406  */
1407 static int __init acpi_no_auto_serialize_setup(char *str)
1408 {
1409 	acpi_gbl_auto_serialize_methods = FALSE;
1410 	pr_info("Auto-serialization disabled\n");
1411 
1412 	return 1;
1413 }
1414 
1415 __setup("acpi_no_auto_serialize", acpi_no_auto_serialize_setup);
1416 
1417 /* Check of resource interference between native drivers and ACPI
1418  * OperationRegions (SystemIO and System Memory only).
1419  * IO ports and memory declared in ACPI might be used by the ACPI subsystem
1420  * in arbitrary AML code and can interfere with legacy drivers.
1421  * acpi_enforce_resources= can be set to:
1422  *
1423  *   - strict (default) (2)
1424  *     -> further driver trying to access the resources will not load
1425  *   - lax              (1)
1426  *     -> further driver trying to access the resources will load, but you
1427  *     get a system message that something might go wrong...
1428  *
1429  *   - no               (0)
1430  *     -> ACPI Operation Region resources will not be registered
1431  *
1432  */
1433 #define ENFORCE_RESOURCES_STRICT 2
1434 #define ENFORCE_RESOURCES_LAX    1
1435 #define ENFORCE_RESOURCES_NO     0
1436 
1437 static unsigned int acpi_enforce_resources = ENFORCE_RESOURCES_STRICT;
1438 
1439 static int __init acpi_enforce_resources_setup(char *str)
1440 {
1441 	if (str == NULL || *str == '\0')
1442 		return 0;
1443 
1444 	if (!strcmp("strict", str))
1445 		acpi_enforce_resources = ENFORCE_RESOURCES_STRICT;
1446 	else if (!strcmp("lax", str))
1447 		acpi_enforce_resources = ENFORCE_RESOURCES_LAX;
1448 	else if (!strcmp("no", str))
1449 		acpi_enforce_resources = ENFORCE_RESOURCES_NO;
1450 
1451 	return 1;
1452 }
1453 
1454 __setup("acpi_enforce_resources=", acpi_enforce_resources_setup);
1455 
1456 /* Check for resource conflicts between ACPI OperationRegions and native
1457  * drivers */
1458 int acpi_check_resource_conflict(const struct resource *res)
1459 {
1460 	acpi_adr_space_type space_id;
1461 
1462 	if (acpi_enforce_resources == ENFORCE_RESOURCES_NO)
1463 		return 0;
1464 
1465 	if (res->flags & IORESOURCE_IO)
1466 		space_id = ACPI_ADR_SPACE_SYSTEM_IO;
1467 	else if (res->flags & IORESOURCE_MEM)
1468 		space_id = ACPI_ADR_SPACE_SYSTEM_MEMORY;
1469 	else
1470 		return 0;
1471 
1472 	if (!acpi_check_address_range(space_id, res->start, resource_size(res), 1))
1473 		return 0;
1474 
1475 	pr_info("Resource conflict; ACPI support missing from driver?\n");
1476 
1477 	if (acpi_enforce_resources == ENFORCE_RESOURCES_STRICT)
1478 		return -EBUSY;
1479 
1480 	if (acpi_enforce_resources == ENFORCE_RESOURCES_LAX)
1481 		pr_notice("Resource conflict: System may be unstable or behave erratically\n");
1482 
1483 	return 0;
1484 }
1485 EXPORT_SYMBOL(acpi_check_resource_conflict);
1486 
1487 int acpi_check_region(resource_size_t start, resource_size_t n,
1488 		      const char *name)
1489 {
1490 	struct resource res = {
1491 		.start = start,
1492 		.end   = start + n - 1,
1493 		.name  = name,
1494 		.flags = IORESOURCE_IO,
1495 	};
1496 
1497 	return acpi_check_resource_conflict(&res);
1498 }
1499 EXPORT_SYMBOL(acpi_check_region);
1500 
1501 static acpi_status acpi_deactivate_mem_region(acpi_handle handle, u32 level,
1502 					      void *_res, void **return_value)
1503 {
1504 	struct acpi_mem_space_context **mem_ctx;
1505 	union acpi_operand_object *handler_obj;
1506 	union acpi_operand_object *region_obj2;
1507 	union acpi_operand_object *region_obj;
1508 	struct resource *res = _res;
1509 	acpi_status status;
1510 
1511 	region_obj = acpi_ns_get_attached_object(handle);
1512 	if (!region_obj)
1513 		return AE_OK;
1514 
1515 	handler_obj = region_obj->region.handler;
1516 	if (!handler_obj)
1517 		return AE_OK;
1518 
1519 	if (region_obj->region.space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY)
1520 		return AE_OK;
1521 
1522 	if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE))
1523 		return AE_OK;
1524 
1525 	region_obj2 = acpi_ns_get_secondary_object(region_obj);
1526 	if (!region_obj2)
1527 		return AE_OK;
1528 
1529 	mem_ctx = (void *)&region_obj2->extra.region_context;
1530 
1531 	if (!(mem_ctx[0]->address >= res->start &&
1532 	      mem_ctx[0]->address < res->end))
1533 		return AE_OK;
1534 
1535 	status = handler_obj->address_space.setup(region_obj,
1536 						  ACPI_REGION_DEACTIVATE,
1537 						  NULL, (void **)mem_ctx);
1538 	if (ACPI_SUCCESS(status))
1539 		region_obj->region.flags &= ~(AOPOBJ_SETUP_COMPLETE);
1540 
1541 	return status;
1542 }
1543 
1544 /**
1545  * acpi_release_memory - Release any mappings done to a memory region
1546  * @handle: Handle to namespace node
1547  * @res: Memory resource
1548  * @level: A level that terminates the search
1549  *
1550  * Walks through @handle and unmaps all SystemMemory Operation Regions that
1551  * overlap with @res and that have already been activated (mapped).
1552  *
1553  * This is a helper that allows drivers to place special requirements on memory
1554  * region that may overlap with operation regions, primarily allowing them to
1555  * safely map the region as non-cached memory.
1556  *
1557  * The unmapped Operation Regions will be automatically remapped next time they
1558  * are called, so the drivers do not need to do anything else.
1559  */
1560 acpi_status acpi_release_memory(acpi_handle handle, struct resource *res,
1561 				u32 level)
1562 {
1563 	acpi_status status;
1564 
1565 	if (!(res->flags & IORESOURCE_MEM))
1566 		return AE_TYPE;
1567 
1568 	status = acpi_walk_namespace(ACPI_TYPE_REGION, handle, level,
1569 				     acpi_deactivate_mem_region, NULL,
1570 				     res, NULL);
1571 	if (ACPI_FAILURE(status))
1572 		return status;
1573 
1574 	/*
1575 	 * Wait for all of the mappings queued up for removal by
1576 	 * acpi_deactivate_mem_region() to actually go away.
1577 	 */
1578 	synchronize_rcu();
1579 	rcu_barrier();
1580 	flush_scheduled_work();
1581 
1582 	return AE_OK;
1583 }
1584 EXPORT_SYMBOL_GPL(acpi_release_memory);
1585 
1586 /*
1587  * Let drivers know whether the resource checks are effective
1588  */
1589 int acpi_resources_are_enforced(void)
1590 {
1591 	return acpi_enforce_resources == ENFORCE_RESOURCES_STRICT;
1592 }
1593 EXPORT_SYMBOL(acpi_resources_are_enforced);
1594 
1595 /*
1596  * Deallocate the memory for a spinlock.
1597  */
1598 void acpi_os_delete_lock(acpi_spinlock handle)
1599 {
1600 	ACPI_FREE(handle);
1601 }
1602 
1603 /*
1604  * Acquire a spinlock.
1605  *
1606  * handle is a pointer to the spinlock_t.
1607  */
1608 
1609 acpi_cpu_flags acpi_os_acquire_lock(acpi_spinlock lockp)
1610 	__acquires(lockp)
1611 {
1612 	acpi_cpu_flags flags;
1613 	spin_lock_irqsave(lockp, flags);
1614 	return flags;
1615 }
1616 
1617 /*
1618  * Release a spinlock. See above.
1619  */
1620 
1621 void acpi_os_release_lock(acpi_spinlock lockp, acpi_cpu_flags flags)
1622 	__releases(lockp)
1623 {
1624 	spin_unlock_irqrestore(lockp, flags);
1625 }
1626 
1627 #ifndef ACPI_USE_LOCAL_CACHE
1628 
1629 /*******************************************************************************
1630  *
1631  * FUNCTION:    acpi_os_create_cache
1632  *
1633  * PARAMETERS:  name      - Ascii name for the cache
1634  *              size      - Size of each cached object
1635  *              depth     - Maximum depth of the cache (in objects) <ignored>
1636  *              cache     - Where the new cache object is returned
1637  *
1638  * RETURN:      status
1639  *
1640  * DESCRIPTION: Create a cache object
1641  *
1642  ******************************************************************************/
1643 
1644 acpi_status
1645 acpi_os_create_cache(char *name, u16 size, u16 depth, acpi_cache_t ** cache)
1646 {
1647 	*cache = kmem_cache_create(name, size, 0, 0, NULL);
1648 	if (*cache == NULL)
1649 		return AE_ERROR;
1650 	else
1651 		return AE_OK;
1652 }
1653 
1654 /*******************************************************************************
1655  *
1656  * FUNCTION:    acpi_os_purge_cache
1657  *
1658  * PARAMETERS:  Cache           - Handle to cache object
1659  *
1660  * RETURN:      Status
1661  *
1662  * DESCRIPTION: Free all objects within the requested cache.
1663  *
1664  ******************************************************************************/
1665 
1666 acpi_status acpi_os_purge_cache(acpi_cache_t * cache)
1667 {
1668 	kmem_cache_shrink(cache);
1669 	return (AE_OK);
1670 }
1671 
1672 /*******************************************************************************
1673  *
1674  * FUNCTION:    acpi_os_delete_cache
1675  *
1676  * PARAMETERS:  Cache           - Handle to cache object
1677  *
1678  * RETURN:      Status
1679  *
1680  * DESCRIPTION: Free all objects within the requested cache and delete the
1681  *              cache object.
1682  *
1683  ******************************************************************************/
1684 
1685 acpi_status acpi_os_delete_cache(acpi_cache_t * cache)
1686 {
1687 	kmem_cache_destroy(cache);
1688 	return (AE_OK);
1689 }
1690 
1691 /*******************************************************************************
1692  *
1693  * FUNCTION:    acpi_os_release_object
1694  *
1695  * PARAMETERS:  Cache       - Handle to cache object
1696  *              Object      - The object to be released
1697  *
1698  * RETURN:      None
1699  *
1700  * DESCRIPTION: Release an object to the specified cache.  If cache is full,
1701  *              the object is deleted.
1702  *
1703  ******************************************************************************/
1704 
1705 acpi_status acpi_os_release_object(acpi_cache_t * cache, void *object)
1706 {
1707 	kmem_cache_free(cache, object);
1708 	return (AE_OK);
1709 }
1710 #endif
1711 
1712 static int __init acpi_no_static_ssdt_setup(char *s)
1713 {
1714 	acpi_gbl_disable_ssdt_table_install = TRUE;
1715 	pr_info("Static SSDT installation disabled\n");
1716 
1717 	return 0;
1718 }
1719 
1720 early_param("acpi_no_static_ssdt", acpi_no_static_ssdt_setup);
1721 
1722 static int __init acpi_disable_return_repair(char *s)
1723 {
1724 	pr_notice("Predefined validation mechanism disabled\n");
1725 	acpi_gbl_disable_auto_repair = TRUE;
1726 
1727 	return 1;
1728 }
1729 
1730 __setup("acpica_no_return_repair", acpi_disable_return_repair);
1731 
1732 acpi_status __init acpi_os_initialize(void)
1733 {
1734 	acpi_os_map_generic_address(&acpi_gbl_FADT.xpm1a_event_block);
1735 	acpi_os_map_generic_address(&acpi_gbl_FADT.xpm1b_event_block);
1736 
1737 	acpi_gbl_xgpe0_block_logical_address =
1738 		(unsigned long)acpi_os_map_generic_address(&acpi_gbl_FADT.xgpe0_block);
1739 	acpi_gbl_xgpe1_block_logical_address =
1740 		(unsigned long)acpi_os_map_generic_address(&acpi_gbl_FADT.xgpe1_block);
1741 
1742 	if (acpi_gbl_FADT.flags & ACPI_FADT_RESET_REGISTER) {
1743 		/*
1744 		 * Use acpi_os_map_generic_address to pre-map the reset
1745 		 * register if it's in system memory.
1746 		 */
1747 		void *rv;
1748 
1749 		rv = acpi_os_map_generic_address(&acpi_gbl_FADT.reset_register);
1750 		pr_debug("%s: Reset register mapping %s\n", __func__,
1751 			 rv ? "successful" : "failed");
1752 	}
1753 	acpi_os_initialized = true;
1754 
1755 	return AE_OK;
1756 }
1757 
1758 acpi_status __init acpi_os_initialize1(void)
1759 {
1760 	kacpid_wq = alloc_workqueue("kacpid", 0, 1);
1761 	kacpi_notify_wq = alloc_workqueue("kacpi_notify", 0, 1);
1762 	kacpi_hotplug_wq = alloc_ordered_workqueue("kacpi_hotplug", 0);
1763 	BUG_ON(!kacpid_wq);
1764 	BUG_ON(!kacpi_notify_wq);
1765 	BUG_ON(!kacpi_hotplug_wq);
1766 	acpi_osi_init();
1767 	return AE_OK;
1768 }
1769 
1770 acpi_status acpi_os_terminate(void)
1771 {
1772 	if (acpi_irq_handler) {
1773 		acpi_os_remove_interrupt_handler(acpi_gbl_FADT.sci_interrupt,
1774 						 acpi_irq_handler);
1775 	}
1776 
1777 	acpi_os_unmap_generic_address(&acpi_gbl_FADT.xgpe1_block);
1778 	acpi_os_unmap_generic_address(&acpi_gbl_FADT.xgpe0_block);
1779 	acpi_gbl_xgpe0_block_logical_address = 0UL;
1780 	acpi_gbl_xgpe1_block_logical_address = 0UL;
1781 
1782 	acpi_os_unmap_generic_address(&acpi_gbl_FADT.xpm1b_event_block);
1783 	acpi_os_unmap_generic_address(&acpi_gbl_FADT.xpm1a_event_block);
1784 
1785 	if (acpi_gbl_FADT.flags & ACPI_FADT_RESET_REGISTER)
1786 		acpi_os_unmap_generic_address(&acpi_gbl_FADT.reset_register);
1787 
1788 	destroy_workqueue(kacpid_wq);
1789 	destroy_workqueue(kacpi_notify_wq);
1790 	destroy_workqueue(kacpi_hotplug_wq);
1791 
1792 	return AE_OK;
1793 }
1794 
1795 acpi_status acpi_os_prepare_sleep(u8 sleep_state, u32 pm1a_control,
1796 				  u32 pm1b_control)
1797 {
1798 	int rc = 0;
1799 	if (__acpi_os_prepare_sleep)
1800 		rc = __acpi_os_prepare_sleep(sleep_state,
1801 					     pm1a_control, pm1b_control);
1802 	if (rc < 0)
1803 		return AE_ERROR;
1804 	else if (rc > 0)
1805 		return AE_CTRL_TERMINATE;
1806 
1807 	return AE_OK;
1808 }
1809 
1810 void acpi_os_set_prepare_sleep(int (*func)(u8 sleep_state,
1811 			       u32 pm1a_ctrl, u32 pm1b_ctrl))
1812 {
1813 	__acpi_os_prepare_sleep = func;
1814 }
1815 
1816 #if (ACPI_REDUCED_HARDWARE)
1817 acpi_status acpi_os_prepare_extended_sleep(u8 sleep_state, u32 val_a,
1818 				  u32 val_b)
1819 {
1820 	int rc = 0;
1821 	if (__acpi_os_prepare_extended_sleep)
1822 		rc = __acpi_os_prepare_extended_sleep(sleep_state,
1823 					     val_a, val_b);
1824 	if (rc < 0)
1825 		return AE_ERROR;
1826 	else if (rc > 0)
1827 		return AE_CTRL_TERMINATE;
1828 
1829 	return AE_OK;
1830 }
1831 #else
1832 acpi_status acpi_os_prepare_extended_sleep(u8 sleep_state, u32 val_a,
1833 				  u32 val_b)
1834 {
1835 	return AE_OK;
1836 }
1837 #endif
1838 
1839 void acpi_os_set_prepare_extended_sleep(int (*func)(u8 sleep_state,
1840 			       u32 val_a, u32 val_b))
1841 {
1842 	__acpi_os_prepare_extended_sleep = func;
1843 }
1844 
1845 acpi_status acpi_os_enter_sleep(u8 sleep_state,
1846 				u32 reg_a_value, u32 reg_b_value)
1847 {
1848 	acpi_status status;
1849 
1850 	if (acpi_gbl_reduced_hardware)
1851 		status = acpi_os_prepare_extended_sleep(sleep_state,
1852 							reg_a_value,
1853 							reg_b_value);
1854 	else
1855 		status = acpi_os_prepare_sleep(sleep_state,
1856 					       reg_a_value, reg_b_value);
1857 	return status;
1858 }
1859