xref: /openbmc/linux/drivers/acpi/osl.c (revision 2dd6532e)
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 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_IA64) || defined(CONFIG_ARM64)
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 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
1071 			  "Scheduling function [%p(%p)] for deferred execution.\n",
1072 			  function, context));
1073 
1074 	if (type == OSL_DEBUGGER_MAIN_THREAD) {
1075 		ret = acpi_debugger_create_thread(function, context);
1076 		if (ret) {
1077 			pr_err("Kernel thread creation failed\n");
1078 			status = AE_ERROR;
1079 		}
1080 		goto out_thread;
1081 	}
1082 
1083 	/*
1084 	 * Allocate/initialize DPC structure.  Note that this memory will be
1085 	 * freed by the callee.  The kernel handles the work_struct list  in a
1086 	 * way that allows us to also free its memory inside the callee.
1087 	 * Because we may want to schedule several tasks with different
1088 	 * parameters we can't use the approach some kernel code uses of
1089 	 * having a static work_struct.
1090 	 */
1091 
1092 	dpc = kzalloc(sizeof(struct acpi_os_dpc), GFP_ATOMIC);
1093 	if (!dpc)
1094 		return AE_NO_MEMORY;
1095 
1096 	dpc->function = function;
1097 	dpc->context = context;
1098 
1099 	/*
1100 	 * To prevent lockdep from complaining unnecessarily, make sure that
1101 	 * there is a different static lockdep key for each workqueue by using
1102 	 * INIT_WORK() for each of them separately.
1103 	 */
1104 	if (type == OSL_NOTIFY_HANDLER) {
1105 		queue = kacpi_notify_wq;
1106 		INIT_WORK(&dpc->work, acpi_os_execute_deferred);
1107 	} else if (type == OSL_GPE_HANDLER) {
1108 		queue = kacpid_wq;
1109 		INIT_WORK(&dpc->work, acpi_os_execute_deferred);
1110 	} else {
1111 		pr_err("Unsupported os_execute type %d.\n", type);
1112 		status = AE_ERROR;
1113 	}
1114 
1115 	if (ACPI_FAILURE(status))
1116 		goto err_workqueue;
1117 
1118 	/*
1119 	 * On some machines, a software-initiated SMI causes corruption unless
1120 	 * the SMI runs on CPU 0.  An SMI can be initiated by any AML, but
1121 	 * typically it's done in GPE-related methods that are run via
1122 	 * workqueues, so we can avoid the known corruption cases by always
1123 	 * queueing on CPU 0.
1124 	 */
1125 	ret = queue_work_on(0, queue, &dpc->work);
1126 	if (!ret) {
1127 		pr_err("Unable to queue work\n");
1128 		status = AE_ERROR;
1129 	}
1130 err_workqueue:
1131 	if (ACPI_FAILURE(status))
1132 		kfree(dpc);
1133 out_thread:
1134 	return status;
1135 }
1136 EXPORT_SYMBOL(acpi_os_execute);
1137 
1138 void acpi_os_wait_events_complete(void)
1139 {
1140 	/*
1141 	 * Make sure the GPE handler or the fixed event handler is not used
1142 	 * on another CPU after removal.
1143 	 */
1144 	if (acpi_sci_irq_valid())
1145 		synchronize_hardirq(acpi_sci_irq);
1146 	flush_workqueue(kacpid_wq);
1147 	flush_workqueue(kacpi_notify_wq);
1148 }
1149 EXPORT_SYMBOL(acpi_os_wait_events_complete);
1150 
1151 struct acpi_hp_work {
1152 	struct work_struct work;
1153 	struct acpi_device *adev;
1154 	u32 src;
1155 };
1156 
1157 static void acpi_hotplug_work_fn(struct work_struct *work)
1158 {
1159 	struct acpi_hp_work *hpw = container_of(work, struct acpi_hp_work, work);
1160 
1161 	acpi_os_wait_events_complete();
1162 	acpi_device_hotplug(hpw->adev, hpw->src);
1163 	kfree(hpw);
1164 }
1165 
1166 acpi_status acpi_hotplug_schedule(struct acpi_device *adev, u32 src)
1167 {
1168 	struct acpi_hp_work *hpw;
1169 
1170 	acpi_handle_debug(adev->handle,
1171 			  "Scheduling hotplug event %u for deferred handling\n",
1172 			   src);
1173 
1174 	hpw = kmalloc(sizeof(*hpw), GFP_KERNEL);
1175 	if (!hpw)
1176 		return AE_NO_MEMORY;
1177 
1178 	INIT_WORK(&hpw->work, acpi_hotplug_work_fn);
1179 	hpw->adev = adev;
1180 	hpw->src = src;
1181 	/*
1182 	 * We can't run hotplug code in kacpid_wq/kacpid_notify_wq etc., because
1183 	 * the hotplug code may call driver .remove() functions, which may
1184 	 * invoke flush_scheduled_work()/acpi_os_wait_events_complete() to flush
1185 	 * these workqueues.
1186 	 */
1187 	if (!queue_work(kacpi_hotplug_wq, &hpw->work)) {
1188 		kfree(hpw);
1189 		return AE_ERROR;
1190 	}
1191 	return AE_OK;
1192 }
1193 
1194 bool acpi_queue_hotplug_work(struct work_struct *work)
1195 {
1196 	return queue_work(kacpi_hotplug_wq, work);
1197 }
1198 
1199 acpi_status
1200 acpi_os_create_semaphore(u32 max_units, u32 initial_units, acpi_handle * handle)
1201 {
1202 	struct semaphore *sem = NULL;
1203 
1204 	sem = acpi_os_allocate_zeroed(sizeof(struct semaphore));
1205 	if (!sem)
1206 		return AE_NO_MEMORY;
1207 
1208 	sema_init(sem, initial_units);
1209 
1210 	*handle = (acpi_handle *) sem;
1211 
1212 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Creating semaphore[%p|%d].\n",
1213 			  *handle, initial_units));
1214 
1215 	return AE_OK;
1216 }
1217 
1218 /*
1219  * TODO: A better way to delete semaphores?  Linux doesn't have a
1220  * 'delete_semaphore()' function -- may result in an invalid
1221  * pointer dereference for non-synchronized consumers.	Should
1222  * we at least check for blocked threads and signal/cancel them?
1223  */
1224 
1225 acpi_status acpi_os_delete_semaphore(acpi_handle handle)
1226 {
1227 	struct semaphore *sem = (struct semaphore *)handle;
1228 
1229 	if (!sem)
1230 		return AE_BAD_PARAMETER;
1231 
1232 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Deleting semaphore[%p].\n", handle));
1233 
1234 	BUG_ON(!list_empty(&sem->wait_list));
1235 	kfree(sem);
1236 	sem = NULL;
1237 
1238 	return AE_OK;
1239 }
1240 
1241 /*
1242  * TODO: Support for units > 1?
1243  */
1244 acpi_status acpi_os_wait_semaphore(acpi_handle handle, u32 units, u16 timeout)
1245 {
1246 	acpi_status status = AE_OK;
1247 	struct semaphore *sem = (struct semaphore *)handle;
1248 	long jiffies;
1249 	int ret = 0;
1250 
1251 	if (!acpi_os_initialized)
1252 		return AE_OK;
1253 
1254 	if (!sem || (units < 1))
1255 		return AE_BAD_PARAMETER;
1256 
1257 	if (units > 1)
1258 		return AE_SUPPORT;
1259 
1260 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Waiting for semaphore[%p|%d|%d]\n",
1261 			  handle, units, timeout));
1262 
1263 	if (timeout == ACPI_WAIT_FOREVER)
1264 		jiffies = MAX_SCHEDULE_TIMEOUT;
1265 	else
1266 		jiffies = msecs_to_jiffies(timeout);
1267 
1268 	ret = down_timeout(sem, jiffies);
1269 	if (ret)
1270 		status = AE_TIME;
1271 
1272 	if (ACPI_FAILURE(status)) {
1273 		ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
1274 				  "Failed to acquire semaphore[%p|%d|%d], %s",
1275 				  handle, units, timeout,
1276 				  acpi_format_exception(status)));
1277 	} else {
1278 		ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
1279 				  "Acquired semaphore[%p|%d|%d]", handle,
1280 				  units, timeout));
1281 	}
1282 
1283 	return status;
1284 }
1285 
1286 /*
1287  * TODO: Support for units > 1?
1288  */
1289 acpi_status acpi_os_signal_semaphore(acpi_handle handle, u32 units)
1290 {
1291 	struct semaphore *sem = (struct semaphore *)handle;
1292 
1293 	if (!acpi_os_initialized)
1294 		return AE_OK;
1295 
1296 	if (!sem || (units < 1))
1297 		return AE_BAD_PARAMETER;
1298 
1299 	if (units > 1)
1300 		return AE_SUPPORT;
1301 
1302 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Signaling semaphore[%p|%d]\n", handle,
1303 			  units));
1304 
1305 	up(sem);
1306 
1307 	return AE_OK;
1308 }
1309 
1310 acpi_status acpi_os_get_line(char *buffer, u32 buffer_length, u32 *bytes_read)
1311 {
1312 #ifdef ENABLE_DEBUGGER
1313 	if (acpi_in_debugger) {
1314 		u32 chars;
1315 
1316 		kdb_read(buffer, buffer_length);
1317 
1318 		/* remove the CR kdb includes */
1319 		chars = strlen(buffer) - 1;
1320 		buffer[chars] = '\0';
1321 	}
1322 #else
1323 	int ret;
1324 
1325 	ret = acpi_debugger_read_cmd(buffer, buffer_length);
1326 	if (ret < 0)
1327 		return AE_ERROR;
1328 	if (bytes_read)
1329 		*bytes_read = ret;
1330 #endif
1331 
1332 	return AE_OK;
1333 }
1334 EXPORT_SYMBOL(acpi_os_get_line);
1335 
1336 acpi_status acpi_os_wait_command_ready(void)
1337 {
1338 	int ret;
1339 
1340 	ret = acpi_debugger_wait_command_ready();
1341 	if (ret < 0)
1342 		return AE_ERROR;
1343 	return AE_OK;
1344 }
1345 
1346 acpi_status acpi_os_notify_command_complete(void)
1347 {
1348 	int ret;
1349 
1350 	ret = acpi_debugger_notify_command_complete();
1351 	if (ret < 0)
1352 		return AE_ERROR;
1353 	return AE_OK;
1354 }
1355 
1356 acpi_status acpi_os_signal(u32 function, void *info)
1357 {
1358 	switch (function) {
1359 	case ACPI_SIGNAL_FATAL:
1360 		pr_err("Fatal opcode executed\n");
1361 		break;
1362 	case ACPI_SIGNAL_BREAKPOINT:
1363 		/*
1364 		 * AML Breakpoint
1365 		 * ACPI spec. says to treat it as a NOP unless
1366 		 * you are debugging.  So if/when we integrate
1367 		 * AML debugger into the kernel debugger its
1368 		 * hook will go here.  But until then it is
1369 		 * not useful to print anything on breakpoints.
1370 		 */
1371 		break;
1372 	default:
1373 		break;
1374 	}
1375 
1376 	return AE_OK;
1377 }
1378 
1379 static int __init acpi_os_name_setup(char *str)
1380 {
1381 	char *p = acpi_os_name;
1382 	int count = ACPI_MAX_OVERRIDE_LEN - 1;
1383 
1384 	if (!str || !*str)
1385 		return 0;
1386 
1387 	for (; count-- && *str; str++) {
1388 		if (isalnum(*str) || *str == ' ' || *str == ':')
1389 			*p++ = *str;
1390 		else if (*str == '\'' || *str == '"')
1391 			continue;
1392 		else
1393 			break;
1394 	}
1395 	*p = 0;
1396 
1397 	return 1;
1398 
1399 }
1400 
1401 __setup("acpi_os_name=", acpi_os_name_setup);
1402 
1403 /*
1404  * Disable the auto-serialization of named objects creation methods.
1405  *
1406  * This feature is enabled by default.  It marks the AML control methods
1407  * that contain the opcodes to create named objects as "Serialized".
1408  */
1409 static int __init acpi_no_auto_serialize_setup(char *str)
1410 {
1411 	acpi_gbl_auto_serialize_methods = FALSE;
1412 	pr_info("Auto-serialization disabled\n");
1413 
1414 	return 1;
1415 }
1416 
1417 __setup("acpi_no_auto_serialize", acpi_no_auto_serialize_setup);
1418 
1419 /* Check of resource interference between native drivers and ACPI
1420  * OperationRegions (SystemIO and System Memory only).
1421  * IO ports and memory declared in ACPI might be used by the ACPI subsystem
1422  * in arbitrary AML code and can interfere with legacy drivers.
1423  * acpi_enforce_resources= can be set to:
1424  *
1425  *   - strict (default) (2)
1426  *     -> further driver trying to access the resources will not load
1427  *   - lax              (1)
1428  *     -> further driver trying to access the resources will load, but you
1429  *     get a system message that something might go wrong...
1430  *
1431  *   - no               (0)
1432  *     -> ACPI Operation Region resources will not be registered
1433  *
1434  */
1435 #define ENFORCE_RESOURCES_STRICT 2
1436 #define ENFORCE_RESOURCES_LAX    1
1437 #define ENFORCE_RESOURCES_NO     0
1438 
1439 static unsigned int acpi_enforce_resources = ENFORCE_RESOURCES_STRICT;
1440 
1441 static int __init acpi_enforce_resources_setup(char *str)
1442 {
1443 	if (str == NULL || *str == '\0')
1444 		return 0;
1445 
1446 	if (!strcmp("strict", str))
1447 		acpi_enforce_resources = ENFORCE_RESOURCES_STRICT;
1448 	else if (!strcmp("lax", str))
1449 		acpi_enforce_resources = ENFORCE_RESOURCES_LAX;
1450 	else if (!strcmp("no", str))
1451 		acpi_enforce_resources = ENFORCE_RESOURCES_NO;
1452 
1453 	return 1;
1454 }
1455 
1456 __setup("acpi_enforce_resources=", acpi_enforce_resources_setup);
1457 
1458 /* Check for resource conflicts between ACPI OperationRegions and native
1459  * drivers */
1460 int acpi_check_resource_conflict(const struct resource *res)
1461 {
1462 	acpi_adr_space_type space_id;
1463 
1464 	if (acpi_enforce_resources == ENFORCE_RESOURCES_NO)
1465 		return 0;
1466 
1467 	if (res->flags & IORESOURCE_IO)
1468 		space_id = ACPI_ADR_SPACE_SYSTEM_IO;
1469 	else if (res->flags & IORESOURCE_MEM)
1470 		space_id = ACPI_ADR_SPACE_SYSTEM_MEMORY;
1471 	else
1472 		return 0;
1473 
1474 	if (!acpi_check_address_range(space_id, res->start, resource_size(res), 1))
1475 		return 0;
1476 
1477 	pr_info("Resource conflict; ACPI support missing from driver?\n");
1478 
1479 	if (acpi_enforce_resources == ENFORCE_RESOURCES_STRICT)
1480 		return -EBUSY;
1481 
1482 	if (acpi_enforce_resources == ENFORCE_RESOURCES_LAX)
1483 		pr_notice("Resource conflict: System may be unstable or behave erratically\n");
1484 
1485 	return 0;
1486 }
1487 EXPORT_SYMBOL(acpi_check_resource_conflict);
1488 
1489 int acpi_check_region(resource_size_t start, resource_size_t n,
1490 		      const char *name)
1491 {
1492 	struct resource res = DEFINE_RES_IO_NAMED(start, n, name);
1493 
1494 	return acpi_check_resource_conflict(&res);
1495 }
1496 EXPORT_SYMBOL(acpi_check_region);
1497 
1498 /*
1499  * Let drivers know whether the resource checks are effective
1500  */
1501 int acpi_resources_are_enforced(void)
1502 {
1503 	return acpi_enforce_resources == ENFORCE_RESOURCES_STRICT;
1504 }
1505 EXPORT_SYMBOL(acpi_resources_are_enforced);
1506 
1507 /*
1508  * Deallocate the memory for a spinlock.
1509  */
1510 void acpi_os_delete_lock(acpi_spinlock handle)
1511 {
1512 	ACPI_FREE(handle);
1513 }
1514 
1515 /*
1516  * Acquire a spinlock.
1517  *
1518  * handle is a pointer to the spinlock_t.
1519  */
1520 
1521 acpi_cpu_flags acpi_os_acquire_lock(acpi_spinlock lockp)
1522 	__acquires(lockp)
1523 {
1524 	acpi_cpu_flags flags;
1525 	spin_lock_irqsave(lockp, flags);
1526 	return flags;
1527 }
1528 
1529 /*
1530  * Release a spinlock. See above.
1531  */
1532 
1533 void acpi_os_release_lock(acpi_spinlock lockp, acpi_cpu_flags flags)
1534 	__releases(lockp)
1535 {
1536 	spin_unlock_irqrestore(lockp, flags);
1537 }
1538 
1539 #ifndef ACPI_USE_LOCAL_CACHE
1540 
1541 /*******************************************************************************
1542  *
1543  * FUNCTION:    acpi_os_create_cache
1544  *
1545  * PARAMETERS:  name      - Ascii name for the cache
1546  *              size      - Size of each cached object
1547  *              depth     - Maximum depth of the cache (in objects) <ignored>
1548  *              cache     - Where the new cache object is returned
1549  *
1550  * RETURN:      status
1551  *
1552  * DESCRIPTION: Create a cache object
1553  *
1554  ******************************************************************************/
1555 
1556 acpi_status
1557 acpi_os_create_cache(char *name, u16 size, u16 depth, acpi_cache_t ** cache)
1558 {
1559 	*cache = kmem_cache_create(name, size, 0, 0, NULL);
1560 	if (*cache == NULL)
1561 		return AE_ERROR;
1562 	else
1563 		return AE_OK;
1564 }
1565 
1566 /*******************************************************************************
1567  *
1568  * FUNCTION:    acpi_os_purge_cache
1569  *
1570  * PARAMETERS:  Cache           - Handle to cache object
1571  *
1572  * RETURN:      Status
1573  *
1574  * DESCRIPTION: Free all objects within the requested cache.
1575  *
1576  ******************************************************************************/
1577 
1578 acpi_status acpi_os_purge_cache(acpi_cache_t * cache)
1579 {
1580 	kmem_cache_shrink(cache);
1581 	return (AE_OK);
1582 }
1583 
1584 /*******************************************************************************
1585  *
1586  * FUNCTION:    acpi_os_delete_cache
1587  *
1588  * PARAMETERS:  Cache           - Handle to cache object
1589  *
1590  * RETURN:      Status
1591  *
1592  * DESCRIPTION: Free all objects within the requested cache and delete the
1593  *              cache object.
1594  *
1595  ******************************************************************************/
1596 
1597 acpi_status acpi_os_delete_cache(acpi_cache_t * cache)
1598 {
1599 	kmem_cache_destroy(cache);
1600 	return (AE_OK);
1601 }
1602 
1603 /*******************************************************************************
1604  *
1605  * FUNCTION:    acpi_os_release_object
1606  *
1607  * PARAMETERS:  Cache       - Handle to cache object
1608  *              Object      - The object to be released
1609  *
1610  * RETURN:      None
1611  *
1612  * DESCRIPTION: Release an object to the specified cache.  If cache is full,
1613  *              the object is deleted.
1614  *
1615  ******************************************************************************/
1616 
1617 acpi_status acpi_os_release_object(acpi_cache_t * cache, void *object)
1618 {
1619 	kmem_cache_free(cache, object);
1620 	return (AE_OK);
1621 }
1622 #endif
1623 
1624 static int __init acpi_no_static_ssdt_setup(char *s)
1625 {
1626 	acpi_gbl_disable_ssdt_table_install = TRUE;
1627 	pr_info("Static SSDT installation disabled\n");
1628 
1629 	return 0;
1630 }
1631 
1632 early_param("acpi_no_static_ssdt", acpi_no_static_ssdt_setup);
1633 
1634 static int __init acpi_disable_return_repair(char *s)
1635 {
1636 	pr_notice("Predefined validation mechanism disabled\n");
1637 	acpi_gbl_disable_auto_repair = TRUE;
1638 
1639 	return 1;
1640 }
1641 
1642 __setup("acpica_no_return_repair", acpi_disable_return_repair);
1643 
1644 acpi_status __init acpi_os_initialize(void)
1645 {
1646 	acpi_os_map_generic_address(&acpi_gbl_FADT.xpm1a_event_block);
1647 	acpi_os_map_generic_address(&acpi_gbl_FADT.xpm1b_event_block);
1648 
1649 	acpi_gbl_xgpe0_block_logical_address =
1650 		(unsigned long)acpi_os_map_generic_address(&acpi_gbl_FADT.xgpe0_block);
1651 	acpi_gbl_xgpe1_block_logical_address =
1652 		(unsigned long)acpi_os_map_generic_address(&acpi_gbl_FADT.xgpe1_block);
1653 
1654 	if (acpi_gbl_FADT.flags & ACPI_FADT_RESET_REGISTER) {
1655 		/*
1656 		 * Use acpi_os_map_generic_address to pre-map the reset
1657 		 * register if it's in system memory.
1658 		 */
1659 		void *rv;
1660 
1661 		rv = acpi_os_map_generic_address(&acpi_gbl_FADT.reset_register);
1662 		pr_debug("%s: Reset register mapping %s\n", __func__,
1663 			 rv ? "successful" : "failed");
1664 	}
1665 	acpi_os_initialized = true;
1666 
1667 	return AE_OK;
1668 }
1669 
1670 acpi_status __init acpi_os_initialize1(void)
1671 {
1672 	kacpid_wq = alloc_workqueue("kacpid", 0, 1);
1673 	kacpi_notify_wq = alloc_workqueue("kacpi_notify", 0, 1);
1674 	kacpi_hotplug_wq = alloc_ordered_workqueue("kacpi_hotplug", 0);
1675 	BUG_ON(!kacpid_wq);
1676 	BUG_ON(!kacpi_notify_wq);
1677 	BUG_ON(!kacpi_hotplug_wq);
1678 	acpi_osi_init();
1679 	return AE_OK;
1680 }
1681 
1682 acpi_status acpi_os_terminate(void)
1683 {
1684 	if (acpi_irq_handler) {
1685 		acpi_os_remove_interrupt_handler(acpi_gbl_FADT.sci_interrupt,
1686 						 acpi_irq_handler);
1687 	}
1688 
1689 	acpi_os_unmap_generic_address(&acpi_gbl_FADT.xgpe1_block);
1690 	acpi_os_unmap_generic_address(&acpi_gbl_FADT.xgpe0_block);
1691 	acpi_gbl_xgpe0_block_logical_address = 0UL;
1692 	acpi_gbl_xgpe1_block_logical_address = 0UL;
1693 
1694 	acpi_os_unmap_generic_address(&acpi_gbl_FADT.xpm1b_event_block);
1695 	acpi_os_unmap_generic_address(&acpi_gbl_FADT.xpm1a_event_block);
1696 
1697 	if (acpi_gbl_FADT.flags & ACPI_FADT_RESET_REGISTER)
1698 		acpi_os_unmap_generic_address(&acpi_gbl_FADT.reset_register);
1699 
1700 	destroy_workqueue(kacpid_wq);
1701 	destroy_workqueue(kacpi_notify_wq);
1702 	destroy_workqueue(kacpi_hotplug_wq);
1703 
1704 	return AE_OK;
1705 }
1706 
1707 acpi_status acpi_os_prepare_sleep(u8 sleep_state, u32 pm1a_control,
1708 				  u32 pm1b_control)
1709 {
1710 	int rc = 0;
1711 	if (__acpi_os_prepare_sleep)
1712 		rc = __acpi_os_prepare_sleep(sleep_state,
1713 					     pm1a_control, pm1b_control);
1714 	if (rc < 0)
1715 		return AE_ERROR;
1716 	else if (rc > 0)
1717 		return AE_CTRL_TERMINATE;
1718 
1719 	return AE_OK;
1720 }
1721 
1722 void acpi_os_set_prepare_sleep(int (*func)(u8 sleep_state,
1723 			       u32 pm1a_ctrl, u32 pm1b_ctrl))
1724 {
1725 	__acpi_os_prepare_sleep = func;
1726 }
1727 
1728 #if (ACPI_REDUCED_HARDWARE)
1729 acpi_status acpi_os_prepare_extended_sleep(u8 sleep_state, u32 val_a,
1730 				  u32 val_b)
1731 {
1732 	int rc = 0;
1733 	if (__acpi_os_prepare_extended_sleep)
1734 		rc = __acpi_os_prepare_extended_sleep(sleep_state,
1735 					     val_a, val_b);
1736 	if (rc < 0)
1737 		return AE_ERROR;
1738 	else if (rc > 0)
1739 		return AE_CTRL_TERMINATE;
1740 
1741 	return AE_OK;
1742 }
1743 #else
1744 acpi_status acpi_os_prepare_extended_sleep(u8 sleep_state, u32 val_a,
1745 				  u32 val_b)
1746 {
1747 	return AE_OK;
1748 }
1749 #endif
1750 
1751 void acpi_os_set_prepare_extended_sleep(int (*func)(u8 sleep_state,
1752 			       u32 val_a, u32 val_b))
1753 {
1754 	__acpi_os_prepare_extended_sleep = func;
1755 }
1756 
1757 acpi_status acpi_os_enter_sleep(u8 sleep_state,
1758 				u32 reg_a_value, u32 reg_b_value)
1759 {
1760 	acpi_status status;
1761 
1762 	if (acpi_gbl_reduced_hardware)
1763 		status = acpi_os_prepare_extended_sleep(sleep_state,
1764 							reg_a_value,
1765 							reg_b_value);
1766 	else
1767 		status = acpi_os_prepare_sleep(sleep_state,
1768 					       reg_a_value, reg_b_value);
1769 	return status;
1770 }
1771