xref: /linux/drivers/acpi/osl.c (revision d642ef71)
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 "internal.h"
40 
41 /* Definitions for ACPI_DEBUG_PRINT() */
42 #define _COMPONENT		ACPI_OS_SERVICES
43 ACPI_MODULE_NAME("osl");
44 
45 struct acpi_os_dpc {
46 	acpi_osd_exec_callback function;
47 	void *context;
48 	struct work_struct work;
49 };
50 
51 #ifdef ENABLE_DEBUGGER
52 #include <linux/kdb.h>
53 
54 /* stuff for debugger support */
55 int acpi_in_debugger;
56 EXPORT_SYMBOL(acpi_in_debugger);
57 #endif				/*ENABLE_DEBUGGER */
58 
59 static int (*__acpi_os_prepare_sleep)(u8 sleep_state, u32 pm1a_ctrl,
60 				      u32 pm1b_ctrl);
61 static int (*__acpi_os_prepare_extended_sleep)(u8 sleep_state, u32 val_a,
62 				      u32 val_b);
63 
64 static acpi_osd_handler acpi_irq_handler;
65 static void *acpi_irq_context;
66 static struct workqueue_struct *kacpid_wq;
67 static struct workqueue_struct *kacpi_notify_wq;
68 static struct workqueue_struct *kacpi_hotplug_wq;
69 static bool acpi_os_initialized;
70 unsigned int acpi_sci_irq = INVALID_ACPI_IRQ;
71 bool acpi_permanent_mmap = false;
72 
73 /*
74  * This list of permanent mappings is for memory that may be accessed from
75  * interrupt context, where we can't do the ioremap().
76  */
77 struct acpi_ioremap {
78 	struct list_head list;
79 	void __iomem *virt;
80 	acpi_physical_address phys;
81 	acpi_size size;
82 	union {
83 		unsigned long refcount;
84 		struct rcu_work rwork;
85 	} track;
86 };
87 
88 static LIST_HEAD(acpi_ioremaps);
89 static DEFINE_MUTEX(acpi_ioremap_lock);
90 #define acpi_ioremap_lock_held() lock_is_held(&acpi_ioremap_lock.dep_map)
91 
92 static void __init acpi_request_region (struct acpi_generic_address *gas,
93 	unsigned int length, char *desc)
94 {
95 	u64 addr;
96 
97 	/* Handle possible alignment issues */
98 	memcpy(&addr, &gas->address, sizeof(addr));
99 	if (!addr || !length)
100 		return;
101 
102 	/* Resources are never freed */
103 	if (gas->space_id == ACPI_ADR_SPACE_SYSTEM_IO)
104 		request_region(addr, length, desc);
105 	else if (gas->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY)
106 		request_mem_region(addr, length, desc);
107 }
108 
109 static int __init acpi_reserve_resources(void)
110 {
111 	acpi_request_region(&acpi_gbl_FADT.xpm1a_event_block, acpi_gbl_FADT.pm1_event_length,
112 		"ACPI PM1a_EVT_BLK");
113 
114 	acpi_request_region(&acpi_gbl_FADT.xpm1b_event_block, acpi_gbl_FADT.pm1_event_length,
115 		"ACPI PM1b_EVT_BLK");
116 
117 	acpi_request_region(&acpi_gbl_FADT.xpm1a_control_block, acpi_gbl_FADT.pm1_control_length,
118 		"ACPI PM1a_CNT_BLK");
119 
120 	acpi_request_region(&acpi_gbl_FADT.xpm1b_control_block, acpi_gbl_FADT.pm1_control_length,
121 		"ACPI PM1b_CNT_BLK");
122 
123 	if (acpi_gbl_FADT.pm_timer_length == 4)
124 		acpi_request_region(&acpi_gbl_FADT.xpm_timer_block, 4, "ACPI PM_TMR");
125 
126 	acpi_request_region(&acpi_gbl_FADT.xpm2_control_block, acpi_gbl_FADT.pm2_control_length,
127 		"ACPI PM2_CNT_BLK");
128 
129 	/* Length of GPE blocks must be a non-negative multiple of 2 */
130 
131 	if (!(acpi_gbl_FADT.gpe0_block_length & 0x1))
132 		acpi_request_region(&acpi_gbl_FADT.xgpe0_block,
133 			       acpi_gbl_FADT.gpe0_block_length, "ACPI GPE0_BLK");
134 
135 	if (!(acpi_gbl_FADT.gpe1_block_length & 0x1))
136 		acpi_request_region(&acpi_gbl_FADT.xgpe1_block,
137 			       acpi_gbl_FADT.gpe1_block_length, "ACPI GPE1_BLK");
138 
139 	return 0;
140 }
141 fs_initcall_sync(acpi_reserve_resources);
142 
143 void acpi_os_printf(const char *fmt, ...)
144 {
145 	va_list args;
146 	va_start(args, fmt);
147 	acpi_os_vprintf(fmt, args);
148 	va_end(args);
149 }
150 EXPORT_SYMBOL(acpi_os_printf);
151 
152 void __printf(1, 0) acpi_os_vprintf(const char *fmt, va_list args)
153 {
154 	static char buffer[512];
155 
156 	vsprintf(buffer, fmt, args);
157 
158 #ifdef ENABLE_DEBUGGER
159 	if (acpi_in_debugger) {
160 		kdb_printf("%s", buffer);
161 	} else {
162 		if (printk_get_level(buffer))
163 			printk("%s", buffer);
164 		else
165 			printk(KERN_CONT "%s", buffer);
166 	}
167 #else
168 	if (acpi_debugger_write_log(buffer) < 0) {
169 		if (printk_get_level(buffer))
170 			printk("%s", buffer);
171 		else
172 			printk(KERN_CONT "%s", buffer);
173 	}
174 #endif
175 }
176 
177 #ifdef CONFIG_KEXEC
178 static unsigned long acpi_rsdp;
179 static int __init setup_acpi_rsdp(char *arg)
180 {
181 	return kstrtoul(arg, 16, &acpi_rsdp);
182 }
183 early_param("acpi_rsdp", setup_acpi_rsdp);
184 #endif
185 
186 acpi_physical_address __init acpi_os_get_root_pointer(void)
187 {
188 	acpi_physical_address pa;
189 
190 #ifdef CONFIG_KEXEC
191 	/*
192 	 * We may have been provided with an RSDP on the command line,
193 	 * but if a malicious user has done so they may be pointing us
194 	 * at modified ACPI tables that could alter kernel behaviour -
195 	 * so, we check the lockdown status before making use of
196 	 * it. If we trust it then also stash it in an architecture
197 	 * specific location (if appropriate) so it can be carried
198 	 * over further kexec()s.
199 	 */
200 	if (acpi_rsdp && !security_locked_down(LOCKDOWN_ACPI_TABLES)) {
201 		acpi_arch_set_root_pointer(acpi_rsdp);
202 		return acpi_rsdp;
203 	}
204 #endif
205 	pa = acpi_arch_get_root_pointer();
206 	if (pa)
207 		return pa;
208 
209 	if (efi_enabled(EFI_CONFIG_TABLES)) {
210 		if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
211 			return efi.acpi20;
212 		if (efi.acpi != EFI_INVALID_TABLE_ADDR)
213 			return efi.acpi;
214 		pr_err("System description tables not found\n");
215 	} else if (IS_ENABLED(CONFIG_ACPI_LEGACY_TABLES_LOOKUP)) {
216 		acpi_find_root_pointer(&pa);
217 	}
218 
219 	return pa;
220 }
221 
222 /* Must be called with 'acpi_ioremap_lock' or RCU read lock held. */
223 static struct acpi_ioremap *
224 acpi_map_lookup(acpi_physical_address phys, acpi_size size)
225 {
226 	struct acpi_ioremap *map;
227 
228 	list_for_each_entry_rcu(map, &acpi_ioremaps, list, acpi_ioremap_lock_held())
229 		if (map->phys <= phys &&
230 		    phys + size <= map->phys + map->size)
231 			return map;
232 
233 	return NULL;
234 }
235 
236 /* Must be called with 'acpi_ioremap_lock' or RCU read lock held. */
237 static void __iomem *
238 acpi_map_vaddr_lookup(acpi_physical_address phys, unsigned int size)
239 {
240 	struct acpi_ioremap *map;
241 
242 	map = acpi_map_lookup(phys, size);
243 	if (map)
244 		return map->virt + (phys - map->phys);
245 
246 	return NULL;
247 }
248 
249 void __iomem *acpi_os_get_iomem(acpi_physical_address phys, unsigned int size)
250 {
251 	struct acpi_ioremap *map;
252 	void __iomem *virt = NULL;
253 
254 	mutex_lock(&acpi_ioremap_lock);
255 	map = acpi_map_lookup(phys, size);
256 	if (map) {
257 		virt = map->virt + (phys - map->phys);
258 		map->track.refcount++;
259 	}
260 	mutex_unlock(&acpi_ioremap_lock);
261 	return virt;
262 }
263 EXPORT_SYMBOL_GPL(acpi_os_get_iomem);
264 
265 /* Must be called with 'acpi_ioremap_lock' or RCU read lock held. */
266 static struct acpi_ioremap *
267 acpi_map_lookup_virt(void __iomem *virt, acpi_size size)
268 {
269 	struct acpi_ioremap *map;
270 
271 	list_for_each_entry_rcu(map, &acpi_ioremaps, list, acpi_ioremap_lock_held())
272 		if (map->virt <= virt &&
273 		    virt + size <= map->virt + map->size)
274 			return map;
275 
276 	return NULL;
277 }
278 
279 #if defined(CONFIG_ARM64) || defined(CONFIG_RISCV)
280 /* ioremap will take care of cache attributes */
281 #define should_use_kmap(pfn)   0
282 #else
283 #define should_use_kmap(pfn)   page_is_ram(pfn)
284 #endif
285 
286 static void __iomem *acpi_map(acpi_physical_address pg_off, unsigned long pg_sz)
287 {
288 	unsigned long pfn;
289 
290 	pfn = pg_off >> PAGE_SHIFT;
291 	if (should_use_kmap(pfn)) {
292 		if (pg_sz > PAGE_SIZE)
293 			return NULL;
294 		return (void __iomem __force *)kmap(pfn_to_page(pfn));
295 	} else
296 		return acpi_os_ioremap(pg_off, pg_sz);
297 }
298 
299 static void acpi_unmap(acpi_physical_address pg_off, void __iomem *vaddr)
300 {
301 	unsigned long pfn;
302 
303 	pfn = pg_off >> PAGE_SHIFT;
304 	if (should_use_kmap(pfn))
305 		kunmap(pfn_to_page(pfn));
306 	else
307 		iounmap(vaddr);
308 }
309 
310 /**
311  * acpi_os_map_iomem - Get a virtual address for a given physical address range.
312  * @phys: Start of the physical address range to map.
313  * @size: Size of the physical address range to map.
314  *
315  * Look up the given physical address range in the list of existing ACPI memory
316  * mappings.  If found, get a reference to it and return a pointer to it (its
317  * virtual address).  If not found, map it, add it to that list and return a
318  * pointer to it.
319  *
320  * During early init (when acpi_permanent_mmap has not been set yet) this
321  * routine simply calls __acpi_map_table() to get the job done.
322  */
323 void __iomem __ref
324 *acpi_os_map_iomem(acpi_physical_address phys, acpi_size size)
325 {
326 	struct acpi_ioremap *map;
327 	void __iomem *virt;
328 	acpi_physical_address pg_off;
329 	acpi_size pg_sz;
330 
331 	if (phys > ULONG_MAX) {
332 		pr_err("Cannot map memory that high: 0x%llx\n", phys);
333 		return NULL;
334 	}
335 
336 	if (!acpi_permanent_mmap)
337 		return __acpi_map_table((unsigned long)phys, size);
338 
339 	mutex_lock(&acpi_ioremap_lock);
340 	/* Check if there's a suitable mapping already. */
341 	map = acpi_map_lookup(phys, size);
342 	if (map) {
343 		map->track.refcount++;
344 		goto out;
345 	}
346 
347 	map = kzalloc(sizeof(*map), GFP_KERNEL);
348 	if (!map) {
349 		mutex_unlock(&acpi_ioremap_lock);
350 		return NULL;
351 	}
352 
353 	pg_off = round_down(phys, PAGE_SIZE);
354 	pg_sz = round_up(phys + size, PAGE_SIZE) - pg_off;
355 	virt = acpi_map(phys, size);
356 	if (!virt) {
357 		mutex_unlock(&acpi_ioremap_lock);
358 		kfree(map);
359 		return NULL;
360 	}
361 
362 	INIT_LIST_HEAD(&map->list);
363 	map->virt = (void __iomem __force *)((unsigned long)virt & PAGE_MASK);
364 	map->phys = pg_off;
365 	map->size = pg_sz;
366 	map->track.refcount = 1;
367 
368 	list_add_tail_rcu(&map->list, &acpi_ioremaps);
369 
370 out:
371 	mutex_unlock(&acpi_ioremap_lock);
372 	return map->virt + (phys - map->phys);
373 }
374 EXPORT_SYMBOL_GPL(acpi_os_map_iomem);
375 
376 void *__ref acpi_os_map_memory(acpi_physical_address phys, acpi_size size)
377 {
378 	return (void *)acpi_os_map_iomem(phys, size);
379 }
380 EXPORT_SYMBOL_GPL(acpi_os_map_memory);
381 
382 static void acpi_os_map_remove(struct work_struct *work)
383 {
384 	struct acpi_ioremap *map = container_of(to_rcu_work(work),
385 						struct acpi_ioremap,
386 						track.rwork);
387 
388 	acpi_unmap(map->phys, map->virt);
389 	kfree(map);
390 }
391 
392 /* Must be called with mutex_lock(&acpi_ioremap_lock) */
393 static void acpi_os_drop_map_ref(struct acpi_ioremap *map)
394 {
395 	if (--map->track.refcount)
396 		return;
397 
398 	list_del_rcu(&map->list);
399 
400 	INIT_RCU_WORK(&map->track.rwork, acpi_os_map_remove);
401 	queue_rcu_work(system_wq, &map->track.rwork);
402 }
403 
404 /**
405  * acpi_os_unmap_iomem - Drop a memory mapping reference.
406  * @virt: Start of the address range to drop a reference to.
407  * @size: Size of the address range to drop a reference to.
408  *
409  * Look up the given virtual address range in the list of existing ACPI memory
410  * mappings, drop a reference to it and if there are no more active references
411  * to it, queue it up for later removal.
412  *
413  * During early init (when acpi_permanent_mmap has not been set yet) this
414  * routine simply calls __acpi_unmap_table() to get the job done.  Since
415  * __acpi_unmap_table() is an __init function, the __ref annotation is needed
416  * here.
417  */
418 void __ref acpi_os_unmap_iomem(void __iomem *virt, acpi_size size)
419 {
420 	struct acpi_ioremap *map;
421 
422 	if (!acpi_permanent_mmap) {
423 		__acpi_unmap_table(virt, size);
424 		return;
425 	}
426 
427 	mutex_lock(&acpi_ioremap_lock);
428 
429 	map = acpi_map_lookup_virt(virt, size);
430 	if (!map) {
431 		mutex_unlock(&acpi_ioremap_lock);
432 		WARN(true, "ACPI: %s: bad address %p\n", __func__, virt);
433 		return;
434 	}
435 	acpi_os_drop_map_ref(map);
436 
437 	mutex_unlock(&acpi_ioremap_lock);
438 }
439 EXPORT_SYMBOL_GPL(acpi_os_unmap_iomem);
440 
441 /**
442  * acpi_os_unmap_memory - Drop a memory mapping reference.
443  * @virt: Start of the address range to drop a reference to.
444  * @size: Size of the address range to drop a reference to.
445  */
446 void __ref acpi_os_unmap_memory(void *virt, acpi_size size)
447 {
448 	acpi_os_unmap_iomem((void __iomem *)virt, size);
449 }
450 EXPORT_SYMBOL_GPL(acpi_os_unmap_memory);
451 
452 void __iomem *acpi_os_map_generic_address(struct acpi_generic_address *gas)
453 {
454 	u64 addr;
455 
456 	if (gas->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY)
457 		return NULL;
458 
459 	/* Handle possible alignment issues */
460 	memcpy(&addr, &gas->address, sizeof(addr));
461 	if (!addr || !gas->bit_width)
462 		return NULL;
463 
464 	return acpi_os_map_iomem(addr, gas->bit_width / 8);
465 }
466 EXPORT_SYMBOL(acpi_os_map_generic_address);
467 
468 void acpi_os_unmap_generic_address(struct acpi_generic_address *gas)
469 {
470 	u64 addr;
471 	struct acpi_ioremap *map;
472 
473 	if (gas->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY)
474 		return;
475 
476 	/* Handle possible alignment issues */
477 	memcpy(&addr, &gas->address, sizeof(addr));
478 	if (!addr || !gas->bit_width)
479 		return;
480 
481 	mutex_lock(&acpi_ioremap_lock);
482 
483 	map = acpi_map_lookup(addr, gas->bit_width / 8);
484 	if (!map) {
485 		mutex_unlock(&acpi_ioremap_lock);
486 		return;
487 	}
488 	acpi_os_drop_map_ref(map);
489 
490 	mutex_unlock(&acpi_ioremap_lock);
491 }
492 EXPORT_SYMBOL(acpi_os_unmap_generic_address);
493 
494 #ifdef ACPI_FUTURE_USAGE
495 acpi_status
496 acpi_os_get_physical_address(void *virt, acpi_physical_address *phys)
497 {
498 	if (!phys || !virt)
499 		return AE_BAD_PARAMETER;
500 
501 	*phys = virt_to_phys(virt);
502 
503 	return AE_OK;
504 }
505 #endif
506 
507 #ifdef CONFIG_ACPI_REV_OVERRIDE_POSSIBLE
508 static bool acpi_rev_override;
509 
510 int __init acpi_rev_override_setup(char *str)
511 {
512 	acpi_rev_override = true;
513 	return 1;
514 }
515 __setup("acpi_rev_override", acpi_rev_override_setup);
516 #else
517 #define acpi_rev_override	false
518 #endif
519 
520 #define ACPI_MAX_OVERRIDE_LEN 100
521 
522 static char acpi_os_name[ACPI_MAX_OVERRIDE_LEN];
523 
524 acpi_status
525 acpi_os_predefined_override(const struct acpi_predefined_names *init_val,
526 			    acpi_string *new_val)
527 {
528 	if (!init_val || !new_val)
529 		return AE_BAD_PARAMETER;
530 
531 	*new_val = NULL;
532 	if (!memcmp(init_val->name, "_OS_", 4) && strlen(acpi_os_name)) {
533 		pr_info("Overriding _OS definition to '%s'\n", acpi_os_name);
534 		*new_val = acpi_os_name;
535 	}
536 
537 	if (!memcmp(init_val->name, "_REV", 4) && acpi_rev_override) {
538 		pr_info("Overriding _REV return value to 5\n");
539 		*new_val = (char *)5;
540 	}
541 
542 	return AE_OK;
543 }
544 
545 static irqreturn_t acpi_irq(int irq, void *dev_id)
546 {
547 	u32 handled;
548 
549 	handled = (*acpi_irq_handler) (acpi_irq_context);
550 
551 	if (handled) {
552 		acpi_irq_handled++;
553 		return IRQ_HANDLED;
554 	} else {
555 		acpi_irq_not_handled++;
556 		return IRQ_NONE;
557 	}
558 }
559 
560 acpi_status
561 acpi_os_install_interrupt_handler(u32 gsi, acpi_osd_handler handler,
562 				  void *context)
563 {
564 	unsigned int irq;
565 
566 	acpi_irq_stats_init();
567 
568 	/*
569 	 * ACPI interrupts different from the SCI in our copy of the FADT are
570 	 * not supported.
571 	 */
572 	if (gsi != acpi_gbl_FADT.sci_interrupt)
573 		return AE_BAD_PARAMETER;
574 
575 	if (acpi_irq_handler)
576 		return AE_ALREADY_ACQUIRED;
577 
578 	if (acpi_gsi_to_irq(gsi, &irq) < 0) {
579 		pr_err("SCI (ACPI GSI %d) not registered\n", gsi);
580 		return AE_OK;
581 	}
582 
583 	acpi_irq_handler = handler;
584 	acpi_irq_context = context;
585 	if (request_irq(irq, acpi_irq, IRQF_SHARED, "acpi", acpi_irq)) {
586 		pr_err("SCI (IRQ%d) allocation failed\n", irq);
587 		acpi_irq_handler = NULL;
588 		return AE_NOT_ACQUIRED;
589 	}
590 	acpi_sci_irq = irq;
591 
592 	return AE_OK;
593 }
594 
595 acpi_status acpi_os_remove_interrupt_handler(u32 gsi, acpi_osd_handler handler)
596 {
597 	if (gsi != acpi_gbl_FADT.sci_interrupt || !acpi_sci_irq_valid())
598 		return AE_BAD_PARAMETER;
599 
600 	free_irq(acpi_sci_irq, acpi_irq);
601 	acpi_irq_handler = NULL;
602 	acpi_sci_irq = INVALID_ACPI_IRQ;
603 
604 	return AE_OK;
605 }
606 
607 /*
608  * Running in interpreter thread context, safe to sleep
609  */
610 
611 void acpi_os_sleep(u64 ms)
612 {
613 	msleep(ms);
614 }
615 
616 void acpi_os_stall(u32 us)
617 {
618 	while (us) {
619 		u32 delay = 1000;
620 
621 		if (delay > us)
622 			delay = us;
623 		udelay(delay);
624 		touch_nmi_watchdog();
625 		us -= delay;
626 	}
627 }
628 
629 /*
630  * Support ACPI 3.0 AML Timer operand. Returns a 64-bit free-running,
631  * monotonically increasing timer with 100ns granularity. Do not use
632  * ktime_get() to implement this function because this function may get
633  * called after timekeeping has been suspended. Note: calling this function
634  * after timekeeping has been suspended may lead to unexpected results
635  * because when timekeeping is suspended the jiffies counter is not
636  * incremented. See also timekeeping_suspend().
637  */
638 u64 acpi_os_get_timer(void)
639 {
640 	return (get_jiffies_64() - INITIAL_JIFFIES) *
641 		(ACPI_100NSEC_PER_SEC / HZ);
642 }
643 
644 acpi_status acpi_os_read_port(acpi_io_address port, u32 *value, u32 width)
645 {
646 	u32 dummy;
647 
648 	if (value)
649 		*value = 0;
650 	else
651 		value = &dummy;
652 
653 	if (width <= 8) {
654 		*value = inb(port);
655 	} else if (width <= 16) {
656 		*value = inw(port);
657 	} else if (width <= 32) {
658 		*value = inl(port);
659 	} else {
660 		pr_debug("%s: Access width %d not supported\n", __func__, width);
661 		return AE_BAD_PARAMETER;
662 	}
663 
664 	return AE_OK;
665 }
666 
667 EXPORT_SYMBOL(acpi_os_read_port);
668 
669 acpi_status acpi_os_write_port(acpi_io_address port, u32 value, u32 width)
670 {
671 	if (width <= 8) {
672 		outb(value, port);
673 	} else if (width <= 16) {
674 		outw(value, port);
675 	} else if (width <= 32) {
676 		outl(value, port);
677 	} else {
678 		pr_debug("%s: Access width %d not supported\n", __func__, width);
679 		return AE_BAD_PARAMETER;
680 	}
681 
682 	return AE_OK;
683 }
684 
685 EXPORT_SYMBOL(acpi_os_write_port);
686 
687 int acpi_os_read_iomem(void __iomem *virt_addr, u64 *value, u32 width)
688 {
689 
690 	switch (width) {
691 	case 8:
692 		*(u8 *) value = readb(virt_addr);
693 		break;
694 	case 16:
695 		*(u16 *) value = readw(virt_addr);
696 		break;
697 	case 32:
698 		*(u32 *) value = readl(virt_addr);
699 		break;
700 	case 64:
701 		*(u64 *) value = readq(virt_addr);
702 		break;
703 	default:
704 		return -EINVAL;
705 	}
706 
707 	return 0;
708 }
709 
710 acpi_status
711 acpi_os_read_memory(acpi_physical_address phys_addr, u64 *value, u32 width)
712 {
713 	void __iomem *virt_addr;
714 	unsigned int size = width / 8;
715 	bool unmap = false;
716 	u64 dummy;
717 	int error;
718 
719 	rcu_read_lock();
720 	virt_addr = acpi_map_vaddr_lookup(phys_addr, size);
721 	if (!virt_addr) {
722 		rcu_read_unlock();
723 		virt_addr = acpi_os_ioremap(phys_addr, size);
724 		if (!virt_addr)
725 			return AE_BAD_ADDRESS;
726 		unmap = true;
727 	}
728 
729 	if (!value)
730 		value = &dummy;
731 
732 	error = acpi_os_read_iomem(virt_addr, value, width);
733 	BUG_ON(error);
734 
735 	if (unmap)
736 		iounmap(virt_addr);
737 	else
738 		rcu_read_unlock();
739 
740 	return AE_OK;
741 }
742 
743 acpi_status
744 acpi_os_write_memory(acpi_physical_address phys_addr, u64 value, u32 width)
745 {
746 	void __iomem *virt_addr;
747 	unsigned int size = width / 8;
748 	bool unmap = false;
749 
750 	rcu_read_lock();
751 	virt_addr = acpi_map_vaddr_lookup(phys_addr, size);
752 	if (!virt_addr) {
753 		rcu_read_unlock();
754 		virt_addr = acpi_os_ioremap(phys_addr, size);
755 		if (!virt_addr)
756 			return AE_BAD_ADDRESS;
757 		unmap = true;
758 	}
759 
760 	switch (width) {
761 	case 8:
762 		writeb(value, virt_addr);
763 		break;
764 	case 16:
765 		writew(value, virt_addr);
766 		break;
767 	case 32:
768 		writel(value, virt_addr);
769 		break;
770 	case 64:
771 		writeq(value, virt_addr);
772 		break;
773 	default:
774 		BUG();
775 	}
776 
777 	if (unmap)
778 		iounmap(virt_addr);
779 	else
780 		rcu_read_unlock();
781 
782 	return AE_OK;
783 }
784 
785 #ifdef CONFIG_PCI
786 acpi_status
787 acpi_os_read_pci_configuration(struct acpi_pci_id *pci_id, u32 reg,
788 			       u64 *value, u32 width)
789 {
790 	int result, size;
791 	u32 value32;
792 
793 	if (!value)
794 		return AE_BAD_PARAMETER;
795 
796 	switch (width) {
797 	case 8:
798 		size = 1;
799 		break;
800 	case 16:
801 		size = 2;
802 		break;
803 	case 32:
804 		size = 4;
805 		break;
806 	default:
807 		return AE_ERROR;
808 	}
809 
810 	result = raw_pci_read(pci_id->segment, pci_id->bus,
811 				PCI_DEVFN(pci_id->device, pci_id->function),
812 				reg, size, &value32);
813 	*value = value32;
814 
815 	return (result ? AE_ERROR : AE_OK);
816 }
817 
818 acpi_status
819 acpi_os_write_pci_configuration(struct acpi_pci_id *pci_id, u32 reg,
820 				u64 value, u32 width)
821 {
822 	int result, size;
823 
824 	switch (width) {
825 	case 8:
826 		size = 1;
827 		break;
828 	case 16:
829 		size = 2;
830 		break;
831 	case 32:
832 		size = 4;
833 		break;
834 	default:
835 		return AE_ERROR;
836 	}
837 
838 	result = raw_pci_write(pci_id->segment, pci_id->bus,
839 				PCI_DEVFN(pci_id->device, pci_id->function),
840 				reg, size, value);
841 
842 	return (result ? AE_ERROR : AE_OK);
843 }
844 #endif
845 
846 static void acpi_os_execute_deferred(struct work_struct *work)
847 {
848 	struct acpi_os_dpc *dpc = container_of(work, struct acpi_os_dpc, work);
849 
850 	dpc->function(dpc->context);
851 	kfree(dpc);
852 }
853 
854 #ifdef CONFIG_ACPI_DEBUGGER
855 static struct acpi_debugger acpi_debugger;
856 static bool acpi_debugger_initialized;
857 
858 int acpi_register_debugger(struct module *owner,
859 			   const struct acpi_debugger_ops *ops)
860 {
861 	int ret = 0;
862 
863 	mutex_lock(&acpi_debugger.lock);
864 	if (acpi_debugger.ops) {
865 		ret = -EBUSY;
866 		goto err_lock;
867 	}
868 
869 	acpi_debugger.owner = owner;
870 	acpi_debugger.ops = ops;
871 
872 err_lock:
873 	mutex_unlock(&acpi_debugger.lock);
874 	return ret;
875 }
876 EXPORT_SYMBOL(acpi_register_debugger);
877 
878 void acpi_unregister_debugger(const struct acpi_debugger_ops *ops)
879 {
880 	mutex_lock(&acpi_debugger.lock);
881 	if (ops == acpi_debugger.ops) {
882 		acpi_debugger.ops = NULL;
883 		acpi_debugger.owner = NULL;
884 	}
885 	mutex_unlock(&acpi_debugger.lock);
886 }
887 EXPORT_SYMBOL(acpi_unregister_debugger);
888 
889 int acpi_debugger_create_thread(acpi_osd_exec_callback function, void *context)
890 {
891 	int ret;
892 	int (*func)(acpi_osd_exec_callback, void *);
893 	struct module *owner;
894 
895 	if (!acpi_debugger_initialized)
896 		return -ENODEV;
897 	mutex_lock(&acpi_debugger.lock);
898 	if (!acpi_debugger.ops) {
899 		ret = -ENODEV;
900 		goto err_lock;
901 	}
902 	if (!try_module_get(acpi_debugger.owner)) {
903 		ret = -ENODEV;
904 		goto err_lock;
905 	}
906 	func = acpi_debugger.ops->create_thread;
907 	owner = acpi_debugger.owner;
908 	mutex_unlock(&acpi_debugger.lock);
909 
910 	ret = func(function, context);
911 
912 	mutex_lock(&acpi_debugger.lock);
913 	module_put(owner);
914 err_lock:
915 	mutex_unlock(&acpi_debugger.lock);
916 	return ret;
917 }
918 
919 ssize_t acpi_debugger_write_log(const char *msg)
920 {
921 	ssize_t ret;
922 	ssize_t (*func)(const char *);
923 	struct module *owner;
924 
925 	if (!acpi_debugger_initialized)
926 		return -ENODEV;
927 	mutex_lock(&acpi_debugger.lock);
928 	if (!acpi_debugger.ops) {
929 		ret = -ENODEV;
930 		goto err_lock;
931 	}
932 	if (!try_module_get(acpi_debugger.owner)) {
933 		ret = -ENODEV;
934 		goto err_lock;
935 	}
936 	func = acpi_debugger.ops->write_log;
937 	owner = acpi_debugger.owner;
938 	mutex_unlock(&acpi_debugger.lock);
939 
940 	ret = func(msg);
941 
942 	mutex_lock(&acpi_debugger.lock);
943 	module_put(owner);
944 err_lock:
945 	mutex_unlock(&acpi_debugger.lock);
946 	return ret;
947 }
948 
949 ssize_t acpi_debugger_read_cmd(char *buffer, size_t buffer_length)
950 {
951 	ssize_t ret;
952 	ssize_t (*func)(char *, size_t);
953 	struct module *owner;
954 
955 	if (!acpi_debugger_initialized)
956 		return -ENODEV;
957 	mutex_lock(&acpi_debugger.lock);
958 	if (!acpi_debugger.ops) {
959 		ret = -ENODEV;
960 		goto err_lock;
961 	}
962 	if (!try_module_get(acpi_debugger.owner)) {
963 		ret = -ENODEV;
964 		goto err_lock;
965 	}
966 	func = acpi_debugger.ops->read_cmd;
967 	owner = acpi_debugger.owner;
968 	mutex_unlock(&acpi_debugger.lock);
969 
970 	ret = func(buffer, buffer_length);
971 
972 	mutex_lock(&acpi_debugger.lock);
973 	module_put(owner);
974 err_lock:
975 	mutex_unlock(&acpi_debugger.lock);
976 	return ret;
977 }
978 
979 int acpi_debugger_wait_command_ready(void)
980 {
981 	int ret;
982 	int (*func)(bool, char *, size_t);
983 	struct module *owner;
984 
985 	if (!acpi_debugger_initialized)
986 		return -ENODEV;
987 	mutex_lock(&acpi_debugger.lock);
988 	if (!acpi_debugger.ops) {
989 		ret = -ENODEV;
990 		goto err_lock;
991 	}
992 	if (!try_module_get(acpi_debugger.owner)) {
993 		ret = -ENODEV;
994 		goto err_lock;
995 	}
996 	func = acpi_debugger.ops->wait_command_ready;
997 	owner = acpi_debugger.owner;
998 	mutex_unlock(&acpi_debugger.lock);
999 
1000 	ret = func(acpi_gbl_method_executing,
1001 		   acpi_gbl_db_line_buf, ACPI_DB_LINE_BUFFER_SIZE);
1002 
1003 	mutex_lock(&acpi_debugger.lock);
1004 	module_put(owner);
1005 err_lock:
1006 	mutex_unlock(&acpi_debugger.lock);
1007 	return ret;
1008 }
1009 
1010 int acpi_debugger_notify_command_complete(void)
1011 {
1012 	int ret;
1013 	int (*func)(void);
1014 	struct module *owner;
1015 
1016 	if (!acpi_debugger_initialized)
1017 		return -ENODEV;
1018 	mutex_lock(&acpi_debugger.lock);
1019 	if (!acpi_debugger.ops) {
1020 		ret = -ENODEV;
1021 		goto err_lock;
1022 	}
1023 	if (!try_module_get(acpi_debugger.owner)) {
1024 		ret = -ENODEV;
1025 		goto err_lock;
1026 	}
1027 	func = acpi_debugger.ops->notify_command_complete;
1028 	owner = acpi_debugger.owner;
1029 	mutex_unlock(&acpi_debugger.lock);
1030 
1031 	ret = func();
1032 
1033 	mutex_lock(&acpi_debugger.lock);
1034 	module_put(owner);
1035 err_lock:
1036 	mutex_unlock(&acpi_debugger.lock);
1037 	return ret;
1038 }
1039 
1040 int __init acpi_debugger_init(void)
1041 {
1042 	mutex_init(&acpi_debugger.lock);
1043 	acpi_debugger_initialized = true;
1044 	return 0;
1045 }
1046 #endif
1047 
1048 /*******************************************************************************
1049  *
1050  * FUNCTION:    acpi_os_execute
1051  *
1052  * PARAMETERS:  Type               - Type of the callback
1053  *              Function           - Function to be executed
1054  *              Context            - Function parameters
1055  *
1056  * RETURN:      Status
1057  *
1058  * DESCRIPTION: Depending on type, either queues function for deferred execution or
1059  *              immediately executes function on a separate thread.
1060  *
1061  ******************************************************************************/
1062 
1063 acpi_status acpi_os_execute(acpi_execute_type type,
1064 			    acpi_osd_exec_callback function, void *context)
1065 {
1066 	acpi_status status = AE_OK;
1067 	struct acpi_os_dpc *dpc;
1068 	struct workqueue_struct *queue;
1069 	int ret;
1070 
1071 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
1072 			  "Scheduling function [%p(%p)] for deferred execution.\n",
1073 			  function, context));
1074 
1075 	if (type == OSL_DEBUGGER_MAIN_THREAD) {
1076 		ret = acpi_debugger_create_thread(function, context);
1077 		if (ret) {
1078 			pr_err("Kernel thread creation failed\n");
1079 			status = AE_ERROR;
1080 		}
1081 		goto out_thread;
1082 	}
1083 
1084 	/*
1085 	 * Allocate/initialize DPC structure.  Note that this memory will be
1086 	 * freed by the callee.  The kernel handles the work_struct list  in a
1087 	 * way that allows us to also free its memory inside the callee.
1088 	 * Because we may want to schedule several tasks with different
1089 	 * parameters we can't use the approach some kernel code uses of
1090 	 * having a static work_struct.
1091 	 */
1092 
1093 	dpc = kzalloc(sizeof(struct acpi_os_dpc), GFP_ATOMIC);
1094 	if (!dpc)
1095 		return AE_NO_MEMORY;
1096 
1097 	dpc->function = function;
1098 	dpc->context = context;
1099 
1100 	/*
1101 	 * To prevent lockdep from complaining unnecessarily, make sure that
1102 	 * there is a different static lockdep key for each workqueue by using
1103 	 * INIT_WORK() for each of them separately.
1104 	 */
1105 	if (type == OSL_NOTIFY_HANDLER) {
1106 		queue = kacpi_notify_wq;
1107 		INIT_WORK(&dpc->work, acpi_os_execute_deferred);
1108 	} else if (type == OSL_GPE_HANDLER) {
1109 		queue = kacpid_wq;
1110 		INIT_WORK(&dpc->work, acpi_os_execute_deferred);
1111 	} else {
1112 		pr_err("Unsupported os_execute type %d.\n", type);
1113 		status = AE_ERROR;
1114 	}
1115 
1116 	if (ACPI_FAILURE(status))
1117 		goto err_workqueue;
1118 
1119 	/*
1120 	 * On some machines, a software-initiated SMI causes corruption unless
1121 	 * the SMI runs on CPU 0.  An SMI can be initiated by any AML, but
1122 	 * typically it's done in GPE-related methods that are run via
1123 	 * workqueues, so we can avoid the known corruption cases by always
1124 	 * queueing on CPU 0.
1125 	 */
1126 	ret = queue_work_on(0, queue, &dpc->work);
1127 	if (!ret) {
1128 		pr_err("Unable to queue work\n");
1129 		status = AE_ERROR;
1130 	}
1131 err_workqueue:
1132 	if (ACPI_FAILURE(status))
1133 		kfree(dpc);
1134 out_thread:
1135 	return status;
1136 }
1137 EXPORT_SYMBOL(acpi_os_execute);
1138 
1139 void acpi_os_wait_events_complete(void)
1140 {
1141 	/*
1142 	 * Make sure the GPE handler or the fixed event handler is not used
1143 	 * on another CPU after removal.
1144 	 */
1145 	if (acpi_sci_irq_valid())
1146 		synchronize_hardirq(acpi_sci_irq);
1147 	flush_workqueue(kacpid_wq);
1148 	flush_workqueue(kacpi_notify_wq);
1149 }
1150 EXPORT_SYMBOL(acpi_os_wait_events_complete);
1151 
1152 struct acpi_hp_work {
1153 	struct work_struct work;
1154 	struct acpi_device *adev;
1155 	u32 src;
1156 };
1157 
1158 static void acpi_hotplug_work_fn(struct work_struct *work)
1159 {
1160 	struct acpi_hp_work *hpw = container_of(work, struct acpi_hp_work, work);
1161 
1162 	acpi_os_wait_events_complete();
1163 	acpi_device_hotplug(hpw->adev, hpw->src);
1164 	kfree(hpw);
1165 }
1166 
1167 acpi_status acpi_hotplug_schedule(struct acpi_device *adev, u32 src)
1168 {
1169 	struct acpi_hp_work *hpw;
1170 
1171 	acpi_handle_debug(adev->handle,
1172 			  "Scheduling hotplug event %u for deferred handling\n",
1173 			   src);
1174 
1175 	hpw = kmalloc(sizeof(*hpw), GFP_KERNEL);
1176 	if (!hpw)
1177 		return AE_NO_MEMORY;
1178 
1179 	INIT_WORK(&hpw->work, acpi_hotplug_work_fn);
1180 	hpw->adev = adev;
1181 	hpw->src = src;
1182 	/*
1183 	 * We can't run hotplug code in kacpid_wq/kacpid_notify_wq etc., because
1184 	 * the hotplug code may call driver .remove() functions, which may
1185 	 * invoke flush_scheduled_work()/acpi_os_wait_events_complete() to flush
1186 	 * these workqueues.
1187 	 */
1188 	if (!queue_work(kacpi_hotplug_wq, &hpw->work)) {
1189 		kfree(hpw);
1190 		return AE_ERROR;
1191 	}
1192 	return AE_OK;
1193 }
1194 
1195 bool acpi_queue_hotplug_work(struct work_struct *work)
1196 {
1197 	return queue_work(kacpi_hotplug_wq, work);
1198 }
1199 
1200 acpi_status
1201 acpi_os_create_semaphore(u32 max_units, u32 initial_units, acpi_handle *handle)
1202 {
1203 	struct semaphore *sem = NULL;
1204 
1205 	sem = acpi_os_allocate_zeroed(sizeof(struct semaphore));
1206 	if (!sem)
1207 		return AE_NO_MEMORY;
1208 
1209 	sema_init(sem, initial_units);
1210 
1211 	*handle = (acpi_handle *) sem;
1212 
1213 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Creating semaphore[%p|%d].\n",
1214 			  *handle, initial_units));
1215 
1216 	return AE_OK;
1217 }
1218 
1219 /*
1220  * TODO: A better way to delete semaphores?  Linux doesn't have a
1221  * 'delete_semaphore()' function -- may result in an invalid
1222  * pointer dereference for non-synchronized consumers.	Should
1223  * we at least check for blocked threads and signal/cancel them?
1224  */
1225 
1226 acpi_status acpi_os_delete_semaphore(acpi_handle handle)
1227 {
1228 	struct semaphore *sem = (struct semaphore *)handle;
1229 
1230 	if (!sem)
1231 		return AE_BAD_PARAMETER;
1232 
1233 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Deleting semaphore[%p].\n", handle));
1234 
1235 	BUG_ON(!list_empty(&sem->wait_list));
1236 	kfree(sem);
1237 	sem = NULL;
1238 
1239 	return AE_OK;
1240 }
1241 
1242 /*
1243  * TODO: Support for units > 1?
1244  */
1245 acpi_status acpi_os_wait_semaphore(acpi_handle handle, u32 units, u16 timeout)
1246 {
1247 	acpi_status status = AE_OK;
1248 	struct semaphore *sem = (struct semaphore *)handle;
1249 	long jiffies;
1250 	int ret = 0;
1251 
1252 	if (!acpi_os_initialized)
1253 		return AE_OK;
1254 
1255 	if (!sem || (units < 1))
1256 		return AE_BAD_PARAMETER;
1257 
1258 	if (units > 1)
1259 		return AE_SUPPORT;
1260 
1261 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Waiting for semaphore[%p|%d|%d]\n",
1262 			  handle, units, timeout));
1263 
1264 	if (timeout == ACPI_WAIT_FOREVER)
1265 		jiffies = MAX_SCHEDULE_TIMEOUT;
1266 	else
1267 		jiffies = msecs_to_jiffies(timeout);
1268 
1269 	ret = down_timeout(sem, jiffies);
1270 	if (ret)
1271 		status = AE_TIME;
1272 
1273 	if (ACPI_FAILURE(status)) {
1274 		ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
1275 				  "Failed to acquire semaphore[%p|%d|%d], %s",
1276 				  handle, units, timeout,
1277 				  acpi_format_exception(status)));
1278 	} else {
1279 		ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
1280 				  "Acquired semaphore[%p|%d|%d]", handle,
1281 				  units, timeout));
1282 	}
1283 
1284 	return status;
1285 }
1286 
1287 /*
1288  * TODO: Support for units > 1?
1289  */
1290 acpi_status acpi_os_signal_semaphore(acpi_handle handle, u32 units)
1291 {
1292 	struct semaphore *sem = (struct semaphore *)handle;
1293 
1294 	if (!acpi_os_initialized)
1295 		return AE_OK;
1296 
1297 	if (!sem || (units < 1))
1298 		return AE_BAD_PARAMETER;
1299 
1300 	if (units > 1)
1301 		return AE_SUPPORT;
1302 
1303 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Signaling semaphore[%p|%d]\n", handle,
1304 			  units));
1305 
1306 	up(sem);
1307 
1308 	return AE_OK;
1309 }
1310 
1311 acpi_status acpi_os_get_line(char *buffer, u32 buffer_length, u32 *bytes_read)
1312 {
1313 #ifdef ENABLE_DEBUGGER
1314 	if (acpi_in_debugger) {
1315 		u32 chars;
1316 
1317 		kdb_read(buffer, buffer_length);
1318 
1319 		/* remove the CR kdb includes */
1320 		chars = strlen(buffer) - 1;
1321 		buffer[chars] = '\0';
1322 	}
1323 #else
1324 	int ret;
1325 
1326 	ret = acpi_debugger_read_cmd(buffer, buffer_length);
1327 	if (ret < 0)
1328 		return AE_ERROR;
1329 	if (bytes_read)
1330 		*bytes_read = ret;
1331 #endif
1332 
1333 	return AE_OK;
1334 }
1335 EXPORT_SYMBOL(acpi_os_get_line);
1336 
1337 acpi_status acpi_os_wait_command_ready(void)
1338 {
1339 	int ret;
1340 
1341 	ret = acpi_debugger_wait_command_ready();
1342 	if (ret < 0)
1343 		return AE_ERROR;
1344 	return AE_OK;
1345 }
1346 
1347 acpi_status acpi_os_notify_command_complete(void)
1348 {
1349 	int ret;
1350 
1351 	ret = acpi_debugger_notify_command_complete();
1352 	if (ret < 0)
1353 		return AE_ERROR;
1354 	return AE_OK;
1355 }
1356 
1357 acpi_status acpi_os_signal(u32 function, void *info)
1358 {
1359 	switch (function) {
1360 	case ACPI_SIGNAL_FATAL:
1361 		pr_err("Fatal opcode executed\n");
1362 		break;
1363 	case ACPI_SIGNAL_BREAKPOINT:
1364 		/*
1365 		 * AML Breakpoint
1366 		 * ACPI spec. says to treat it as a NOP unless
1367 		 * you are debugging.  So if/when we integrate
1368 		 * AML debugger into the kernel debugger its
1369 		 * hook will go here.  But until then it is
1370 		 * not useful to print anything on breakpoints.
1371 		 */
1372 		break;
1373 	default:
1374 		break;
1375 	}
1376 
1377 	return AE_OK;
1378 }
1379 
1380 static int __init acpi_os_name_setup(char *str)
1381 {
1382 	char *p = acpi_os_name;
1383 	int count = ACPI_MAX_OVERRIDE_LEN - 1;
1384 
1385 	if (!str || !*str)
1386 		return 0;
1387 
1388 	for (; count-- && *str; str++) {
1389 		if (isalnum(*str) || *str == ' ' || *str == ':')
1390 			*p++ = *str;
1391 		else if (*str == '\'' || *str == '"')
1392 			continue;
1393 		else
1394 			break;
1395 	}
1396 	*p = 0;
1397 
1398 	return 1;
1399 
1400 }
1401 
1402 __setup("acpi_os_name=", acpi_os_name_setup);
1403 
1404 /*
1405  * Disable the auto-serialization of named objects creation methods.
1406  *
1407  * This feature is enabled by default.  It marks the AML control methods
1408  * that contain the opcodes to create named objects as "Serialized".
1409  */
1410 static int __init acpi_no_auto_serialize_setup(char *str)
1411 {
1412 	acpi_gbl_auto_serialize_methods = FALSE;
1413 	pr_info("Auto-serialization disabled\n");
1414 
1415 	return 1;
1416 }
1417 
1418 __setup("acpi_no_auto_serialize", acpi_no_auto_serialize_setup);
1419 
1420 /* Check of resource interference between native drivers and ACPI
1421  * OperationRegions (SystemIO and System Memory only).
1422  * IO ports and memory declared in ACPI might be used by the ACPI subsystem
1423  * in arbitrary AML code and can interfere with legacy drivers.
1424  * acpi_enforce_resources= can be set to:
1425  *
1426  *   - strict (default) (2)
1427  *     -> further driver trying to access the resources will not load
1428  *   - lax              (1)
1429  *     -> further driver trying to access the resources will load, but you
1430  *     get a system message that something might go wrong...
1431  *
1432  *   - no               (0)
1433  *     -> ACPI Operation Region resources will not be registered
1434  *
1435  */
1436 #define ENFORCE_RESOURCES_STRICT 2
1437 #define ENFORCE_RESOURCES_LAX    1
1438 #define ENFORCE_RESOURCES_NO     0
1439 
1440 static unsigned int acpi_enforce_resources = ENFORCE_RESOURCES_STRICT;
1441 
1442 static int __init acpi_enforce_resources_setup(char *str)
1443 {
1444 	if (str == NULL || *str == '\0')
1445 		return 0;
1446 
1447 	if (!strcmp("strict", str))
1448 		acpi_enforce_resources = ENFORCE_RESOURCES_STRICT;
1449 	else if (!strcmp("lax", str))
1450 		acpi_enforce_resources = ENFORCE_RESOURCES_LAX;
1451 	else if (!strcmp("no", str))
1452 		acpi_enforce_resources = ENFORCE_RESOURCES_NO;
1453 
1454 	return 1;
1455 }
1456 
1457 __setup("acpi_enforce_resources=", acpi_enforce_resources_setup);
1458 
1459 /* Check for resource conflicts between ACPI OperationRegions and native
1460  * drivers */
1461 int acpi_check_resource_conflict(const struct resource *res)
1462 {
1463 	acpi_adr_space_type space_id;
1464 
1465 	if (acpi_enforce_resources == ENFORCE_RESOURCES_NO)
1466 		return 0;
1467 
1468 	if (res->flags & IORESOURCE_IO)
1469 		space_id = ACPI_ADR_SPACE_SYSTEM_IO;
1470 	else if (res->flags & IORESOURCE_MEM)
1471 		space_id = ACPI_ADR_SPACE_SYSTEM_MEMORY;
1472 	else
1473 		return 0;
1474 
1475 	if (!acpi_check_address_range(space_id, res->start, resource_size(res), 1))
1476 		return 0;
1477 
1478 	pr_info("Resource conflict; ACPI support missing from driver?\n");
1479 
1480 	if (acpi_enforce_resources == ENFORCE_RESOURCES_STRICT)
1481 		return -EBUSY;
1482 
1483 	if (acpi_enforce_resources == ENFORCE_RESOURCES_LAX)
1484 		pr_notice("Resource conflict: System may be unstable or behave erratically\n");
1485 
1486 	return 0;
1487 }
1488 EXPORT_SYMBOL(acpi_check_resource_conflict);
1489 
1490 int acpi_check_region(resource_size_t start, resource_size_t n,
1491 		      const char *name)
1492 {
1493 	struct resource res = DEFINE_RES_IO_NAMED(start, n, name);
1494 
1495 	return acpi_check_resource_conflict(&res);
1496 }
1497 EXPORT_SYMBOL(acpi_check_region);
1498 
1499 /*
1500  * Let drivers know whether the resource checks are effective
1501  */
1502 int acpi_resources_are_enforced(void)
1503 {
1504 	return acpi_enforce_resources == ENFORCE_RESOURCES_STRICT;
1505 }
1506 EXPORT_SYMBOL(acpi_resources_are_enforced);
1507 
1508 /*
1509  * Deallocate the memory for a spinlock.
1510  */
1511 void acpi_os_delete_lock(acpi_spinlock handle)
1512 {
1513 	ACPI_FREE(handle);
1514 }
1515 
1516 /*
1517  * Acquire a spinlock.
1518  *
1519  * handle is a pointer to the spinlock_t.
1520  */
1521 
1522 acpi_cpu_flags acpi_os_acquire_lock(acpi_spinlock lockp)
1523 	__acquires(lockp)
1524 {
1525 	acpi_cpu_flags flags;
1526 
1527 	spin_lock_irqsave(lockp, flags);
1528 	return flags;
1529 }
1530 
1531 /*
1532  * Release a spinlock. See above.
1533  */
1534 
1535 void acpi_os_release_lock(acpi_spinlock lockp, acpi_cpu_flags flags)
1536 	__releases(lockp)
1537 {
1538 	spin_unlock_irqrestore(lockp, flags);
1539 }
1540 
1541 #ifndef ACPI_USE_LOCAL_CACHE
1542 
1543 /*******************************************************************************
1544  *
1545  * FUNCTION:    acpi_os_create_cache
1546  *
1547  * PARAMETERS:  name      - Ascii name for the cache
1548  *              size      - Size of each cached object
1549  *              depth     - Maximum depth of the cache (in objects) <ignored>
1550  *              cache     - Where the new cache object is returned
1551  *
1552  * RETURN:      status
1553  *
1554  * DESCRIPTION: Create a cache object
1555  *
1556  ******************************************************************************/
1557 
1558 acpi_status
1559 acpi_os_create_cache(char *name, u16 size, u16 depth, acpi_cache_t **cache)
1560 {
1561 	*cache = kmem_cache_create(name, size, 0, 0, NULL);
1562 	if (*cache == NULL)
1563 		return AE_ERROR;
1564 	else
1565 		return AE_OK;
1566 }
1567 
1568 /*******************************************************************************
1569  *
1570  * FUNCTION:    acpi_os_purge_cache
1571  *
1572  * PARAMETERS:  Cache           - Handle to cache object
1573  *
1574  * RETURN:      Status
1575  *
1576  * DESCRIPTION: Free all objects within the requested cache.
1577  *
1578  ******************************************************************************/
1579 
1580 acpi_status acpi_os_purge_cache(acpi_cache_t *cache)
1581 {
1582 	kmem_cache_shrink(cache);
1583 	return AE_OK;
1584 }
1585 
1586 /*******************************************************************************
1587  *
1588  * FUNCTION:    acpi_os_delete_cache
1589  *
1590  * PARAMETERS:  Cache           - Handle to cache object
1591  *
1592  * RETURN:      Status
1593  *
1594  * DESCRIPTION: Free all objects within the requested cache and delete the
1595  *              cache object.
1596  *
1597  ******************************************************************************/
1598 
1599 acpi_status acpi_os_delete_cache(acpi_cache_t *cache)
1600 {
1601 	kmem_cache_destroy(cache);
1602 	return AE_OK;
1603 }
1604 
1605 /*******************************************************************************
1606  *
1607  * FUNCTION:    acpi_os_release_object
1608  *
1609  * PARAMETERS:  Cache       - Handle to cache object
1610  *              Object      - The object to be released
1611  *
1612  * RETURN:      None
1613  *
1614  * DESCRIPTION: Release an object to the specified cache.  If cache is full,
1615  *              the object is deleted.
1616  *
1617  ******************************************************************************/
1618 
1619 acpi_status acpi_os_release_object(acpi_cache_t *cache, void *object)
1620 {
1621 	kmem_cache_free(cache, object);
1622 	return AE_OK;
1623 }
1624 #endif
1625 
1626 static int __init acpi_no_static_ssdt_setup(char *s)
1627 {
1628 	acpi_gbl_disable_ssdt_table_install = TRUE;
1629 	pr_info("Static SSDT installation disabled\n");
1630 
1631 	return 0;
1632 }
1633 
1634 early_param("acpi_no_static_ssdt", acpi_no_static_ssdt_setup);
1635 
1636 static int __init acpi_disable_return_repair(char *s)
1637 {
1638 	pr_notice("Predefined validation mechanism disabled\n");
1639 	acpi_gbl_disable_auto_repair = TRUE;
1640 
1641 	return 1;
1642 }
1643 
1644 __setup("acpica_no_return_repair", acpi_disable_return_repair);
1645 
1646 acpi_status __init acpi_os_initialize(void)
1647 {
1648 	acpi_os_map_generic_address(&acpi_gbl_FADT.xpm1a_event_block);
1649 	acpi_os_map_generic_address(&acpi_gbl_FADT.xpm1b_event_block);
1650 
1651 	acpi_gbl_xgpe0_block_logical_address =
1652 		(unsigned long)acpi_os_map_generic_address(&acpi_gbl_FADT.xgpe0_block);
1653 	acpi_gbl_xgpe1_block_logical_address =
1654 		(unsigned long)acpi_os_map_generic_address(&acpi_gbl_FADT.xgpe1_block);
1655 
1656 	if (acpi_gbl_FADT.flags & ACPI_FADT_RESET_REGISTER) {
1657 		/*
1658 		 * Use acpi_os_map_generic_address to pre-map the reset
1659 		 * register if it's in system memory.
1660 		 */
1661 		void *rv;
1662 
1663 		rv = acpi_os_map_generic_address(&acpi_gbl_FADT.reset_register);
1664 		pr_debug("%s: Reset register mapping %s\n", __func__,
1665 			 rv ? "successful" : "failed");
1666 	}
1667 	acpi_os_initialized = true;
1668 
1669 	return AE_OK;
1670 }
1671 
1672 acpi_status __init acpi_os_initialize1(void)
1673 {
1674 	kacpid_wq = alloc_workqueue("kacpid", 0, 1);
1675 	kacpi_notify_wq = alloc_workqueue("kacpi_notify", 0, 1);
1676 	kacpi_hotplug_wq = alloc_ordered_workqueue("kacpi_hotplug", 0);
1677 	BUG_ON(!kacpid_wq);
1678 	BUG_ON(!kacpi_notify_wq);
1679 	BUG_ON(!kacpi_hotplug_wq);
1680 	acpi_osi_init();
1681 	return AE_OK;
1682 }
1683 
1684 acpi_status acpi_os_terminate(void)
1685 {
1686 	if (acpi_irq_handler) {
1687 		acpi_os_remove_interrupt_handler(acpi_gbl_FADT.sci_interrupt,
1688 						 acpi_irq_handler);
1689 	}
1690 
1691 	acpi_os_unmap_generic_address(&acpi_gbl_FADT.xgpe1_block);
1692 	acpi_os_unmap_generic_address(&acpi_gbl_FADT.xgpe0_block);
1693 	acpi_gbl_xgpe0_block_logical_address = 0UL;
1694 	acpi_gbl_xgpe1_block_logical_address = 0UL;
1695 
1696 	acpi_os_unmap_generic_address(&acpi_gbl_FADT.xpm1b_event_block);
1697 	acpi_os_unmap_generic_address(&acpi_gbl_FADT.xpm1a_event_block);
1698 
1699 	if (acpi_gbl_FADT.flags & ACPI_FADT_RESET_REGISTER)
1700 		acpi_os_unmap_generic_address(&acpi_gbl_FADT.reset_register);
1701 
1702 	destroy_workqueue(kacpid_wq);
1703 	destroy_workqueue(kacpi_notify_wq);
1704 	destroy_workqueue(kacpi_hotplug_wq);
1705 
1706 	return AE_OK;
1707 }
1708 
1709 acpi_status acpi_os_prepare_sleep(u8 sleep_state, u32 pm1a_control,
1710 				  u32 pm1b_control)
1711 {
1712 	int rc = 0;
1713 
1714 	if (__acpi_os_prepare_sleep)
1715 		rc = __acpi_os_prepare_sleep(sleep_state,
1716 					     pm1a_control, pm1b_control);
1717 	if (rc < 0)
1718 		return AE_ERROR;
1719 	else if (rc > 0)
1720 		return AE_CTRL_TERMINATE;
1721 
1722 	return AE_OK;
1723 }
1724 
1725 void acpi_os_set_prepare_sleep(int (*func)(u8 sleep_state,
1726 			       u32 pm1a_ctrl, u32 pm1b_ctrl))
1727 {
1728 	__acpi_os_prepare_sleep = func;
1729 }
1730 
1731 #if (ACPI_REDUCED_HARDWARE)
1732 acpi_status acpi_os_prepare_extended_sleep(u8 sleep_state, u32 val_a,
1733 				  u32 val_b)
1734 {
1735 	int rc = 0;
1736 
1737 	if (__acpi_os_prepare_extended_sleep)
1738 		rc = __acpi_os_prepare_extended_sleep(sleep_state,
1739 					     val_a, val_b);
1740 	if (rc < 0)
1741 		return AE_ERROR;
1742 	else if (rc > 0)
1743 		return AE_CTRL_TERMINATE;
1744 
1745 	return AE_OK;
1746 }
1747 #else
1748 acpi_status acpi_os_prepare_extended_sleep(u8 sleep_state, u32 val_a,
1749 				  u32 val_b)
1750 {
1751 	return AE_OK;
1752 }
1753 #endif
1754 
1755 void acpi_os_set_prepare_extended_sleep(int (*func)(u8 sleep_state,
1756 			       u32 val_a, u32 val_b))
1757 {
1758 	__acpi_os_prepare_extended_sleep = func;
1759 }
1760 
1761 acpi_status acpi_os_enter_sleep(u8 sleep_state,
1762 				u32 reg_a_value, u32 reg_b_value)
1763 {
1764 	acpi_status status;
1765 
1766 	if (acpi_gbl_reduced_hardware)
1767 		status = acpi_os_prepare_extended_sleep(sleep_state,
1768 							reg_a_value,
1769 							reg_b_value);
1770 	else
1771 		status = acpi_os_prepare_sleep(sleep_state,
1772 					       reg_a_value, reg_b_value);
1773 	return status;
1774 }
1775