xref: /linux/drivers/acpi/osl.c (revision d8327c784b51b57dac2c26cfad87dce0d68dfd98)
1 /*
2  *  acpi_osl.c - OS-dependent functions ($Revision: 83 $)
3  *
4  *  Copyright (C) 2000       Andrew Henroid
5  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7  *
8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9  *
10  *  This program is free software; you can redistribute it and/or modify
11  *  it under the terms of the GNU General Public License as published by
12  *  the Free Software Foundation; either version 2 of the License, or
13  *  (at your option) any later version.
14  *
15  *  This program is distributed in the hope that it will be useful,
16  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  *  GNU General Public License for more details.
19  *
20  *  You should have received a copy of the GNU General Public License
21  *  along with this program; if not, write to the Free Software
22  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
23  *
24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25  *
26  */
27 
28 #include <linux/config.h>
29 #include <linux/module.h>
30 #include <linux/kernel.h>
31 #include <linux/slab.h>
32 #include <linux/mm.h>
33 #include <linux/pci.h>
34 #include <linux/smp_lock.h>
35 #include <linux/interrupt.h>
36 #include <linux/kmod.h>
37 #include <linux/delay.h>
38 #include <linux/workqueue.h>
39 #include <linux/nmi.h>
40 #include <acpi/acpi.h>
41 #include <asm/io.h>
42 #include <acpi/acpi_bus.h>
43 #include <acpi/processor.h>
44 #include <asm/uaccess.h>
45 
46 #include <linux/efi.h>
47 
48 #define _COMPONENT		ACPI_OS_SERVICES
49 ACPI_MODULE_NAME("osl")
50 #define PREFIX		"ACPI: "
51 struct acpi_os_dpc {
52 	acpi_osd_exec_callback function;
53 	void *context;
54 };
55 
56 #ifdef CONFIG_ACPI_CUSTOM_DSDT
57 #include CONFIG_ACPI_CUSTOM_DSDT_FILE
58 #endif
59 
60 #ifdef ENABLE_DEBUGGER
61 #include <linux/kdb.h>
62 
63 /* stuff for debugger support */
64 int acpi_in_debugger;
65 EXPORT_SYMBOL(acpi_in_debugger);
66 
67 extern char line_buf[80];
68 #endif				/*ENABLE_DEBUGGER */
69 
70 int acpi_specific_hotkey_enabled = TRUE;
71 EXPORT_SYMBOL(acpi_specific_hotkey_enabled);
72 
73 static unsigned int acpi_irq_irq;
74 static acpi_osd_handler acpi_irq_handler;
75 static void *acpi_irq_context;
76 static struct workqueue_struct *kacpid_wq;
77 
78 acpi_status acpi_os_initialize(void)
79 {
80 	return AE_OK;
81 }
82 
83 acpi_status acpi_os_initialize1(void)
84 {
85 	/*
86 	 * Initialize PCI configuration space access, as we'll need to access
87 	 * it while walking the namespace (bus 0 and root bridges w/ _BBNs).
88 	 */
89 	if (!raw_pci_ops) {
90 		printk(KERN_ERR PREFIX
91 		       "Access to PCI configuration space unavailable\n");
92 		return AE_NULL_ENTRY;
93 	}
94 	kacpid_wq = create_singlethread_workqueue("kacpid");
95 	BUG_ON(!kacpid_wq);
96 
97 	return AE_OK;
98 }
99 
100 acpi_status acpi_os_terminate(void)
101 {
102 	if (acpi_irq_handler) {
103 		acpi_os_remove_interrupt_handler(acpi_irq_irq,
104 						 acpi_irq_handler);
105 	}
106 
107 	destroy_workqueue(kacpid_wq);
108 
109 	return AE_OK;
110 }
111 
112 void acpi_os_printf(const char *fmt, ...)
113 {
114 	va_list args;
115 	va_start(args, fmt);
116 	acpi_os_vprintf(fmt, args);
117 	va_end(args);
118 }
119 
120 EXPORT_SYMBOL(acpi_os_printf);
121 
122 void acpi_os_vprintf(const char *fmt, va_list args)
123 {
124 	static char buffer[512];
125 
126 	vsprintf(buffer, fmt, args);
127 
128 #ifdef ENABLE_DEBUGGER
129 	if (acpi_in_debugger) {
130 		kdb_printf("%s", buffer);
131 	} else {
132 		printk("%s", buffer);
133 	}
134 #else
135 	printk("%s", buffer);
136 #endif
137 }
138 
139 extern int acpi_in_resume;
140 void *acpi_os_allocate(acpi_size size)
141 {
142 	if (acpi_in_resume)
143 		return kmalloc(size, GFP_ATOMIC);
144 	else
145 		return kmalloc(size, GFP_KERNEL);
146 }
147 
148 void acpi_os_free(void *ptr)
149 {
150 	kfree(ptr);
151 }
152 
153 EXPORT_SYMBOL(acpi_os_free);
154 
155 acpi_status acpi_os_get_root_pointer(u32 flags, struct acpi_pointer *addr)
156 {
157 	if (efi_enabled) {
158 		addr->pointer_type = ACPI_PHYSICAL_POINTER;
159 		if (efi.acpi20)
160 			addr->pointer.physical =
161 			    (acpi_physical_address) virt_to_phys(efi.acpi20);
162 		else if (efi.acpi)
163 			addr->pointer.physical =
164 			    (acpi_physical_address) virt_to_phys(efi.acpi);
165 		else {
166 			printk(KERN_ERR PREFIX
167 			       "System description tables not found\n");
168 			return AE_NOT_FOUND;
169 		}
170 	} else {
171 		if (ACPI_FAILURE(acpi_find_root_pointer(flags, addr))) {
172 			printk(KERN_ERR PREFIX
173 			       "System description tables not found\n");
174 			return AE_NOT_FOUND;
175 		}
176 	}
177 
178 	return AE_OK;
179 }
180 
181 acpi_status
182 acpi_os_map_memory(acpi_physical_address phys, acpi_size size,
183 		   void __iomem ** virt)
184 {
185 	if (efi_enabled) {
186 		if (EFI_MEMORY_WB & efi_mem_attributes(phys)) {
187 			*virt = (void __iomem *)phys_to_virt(phys);
188 		} else {
189 			*virt = ioremap(phys, size);
190 		}
191 	} else {
192 		if (phys > ULONG_MAX) {
193 			printk(KERN_ERR PREFIX "Cannot map memory that high\n");
194 			return AE_BAD_PARAMETER;
195 		}
196 		/*
197 		 * ioremap checks to ensure this is in reserved space
198 		 */
199 		*virt = ioremap((unsigned long)phys, size);
200 	}
201 
202 	if (!*virt)
203 		return AE_NO_MEMORY;
204 
205 	return AE_OK;
206 }
207 EXPORT_SYMBOL_GPL(acpi_os_map_memory);
208 
209 void acpi_os_unmap_memory(void __iomem * virt, acpi_size size)
210 {
211 	iounmap(virt);
212 }
213 EXPORT_SYMBOL_GPL(acpi_os_unmap_memory);
214 
215 #ifdef ACPI_FUTURE_USAGE
216 acpi_status
217 acpi_os_get_physical_address(void *virt, acpi_physical_address * phys)
218 {
219 	if (!phys || !virt)
220 		return AE_BAD_PARAMETER;
221 
222 	*phys = virt_to_phys(virt);
223 
224 	return AE_OK;
225 }
226 #endif
227 
228 #define ACPI_MAX_OVERRIDE_LEN 100
229 
230 static char acpi_os_name[ACPI_MAX_OVERRIDE_LEN];
231 
232 acpi_status
233 acpi_os_predefined_override(const struct acpi_predefined_names *init_val,
234 			    acpi_string * new_val)
235 {
236 	if (!init_val || !new_val)
237 		return AE_BAD_PARAMETER;
238 
239 	*new_val = NULL;
240 	if (!memcmp(init_val->name, "_OS_", 4) && strlen(acpi_os_name)) {
241 		printk(KERN_INFO PREFIX "Overriding _OS definition to '%s'\n",
242 		       acpi_os_name);
243 		*new_val = acpi_os_name;
244 	}
245 
246 	return AE_OK;
247 }
248 
249 acpi_status
250 acpi_os_table_override(struct acpi_table_header * existing_table,
251 		       struct acpi_table_header ** new_table)
252 {
253 	if (!existing_table || !new_table)
254 		return AE_BAD_PARAMETER;
255 
256 #ifdef CONFIG_ACPI_CUSTOM_DSDT
257 	if (strncmp(existing_table->signature, "DSDT", 4) == 0)
258 		*new_table = (struct acpi_table_header *)AmlCode;
259 	else
260 		*new_table = NULL;
261 #else
262 	*new_table = NULL;
263 #endif
264 	return AE_OK;
265 }
266 
267 static irqreturn_t acpi_irq(int irq, void *dev_id, struct pt_regs *regs)
268 {
269 	return (*acpi_irq_handler) (acpi_irq_context) ? IRQ_HANDLED : IRQ_NONE;
270 }
271 
272 acpi_status
273 acpi_os_install_interrupt_handler(u32 gsi, acpi_osd_handler handler,
274 				  void *context)
275 {
276 	unsigned int irq;
277 
278 	/*
279 	 * Ignore the GSI from the core, and use the value in our copy of the
280 	 * FADT. It may not be the same if an interrupt source override exists
281 	 * for the SCI.
282 	 */
283 	gsi = acpi_fadt.sci_int;
284 	if (acpi_gsi_to_irq(gsi, &irq) < 0) {
285 		printk(KERN_ERR PREFIX "SCI (ACPI GSI %d) not registered\n",
286 		       gsi);
287 		return AE_OK;
288 	}
289 
290 	acpi_irq_handler = handler;
291 	acpi_irq_context = context;
292 	if (request_irq(irq, acpi_irq, SA_SHIRQ, "acpi", acpi_irq)) {
293 		printk(KERN_ERR PREFIX "SCI (IRQ%d) allocation failed\n", irq);
294 		return AE_NOT_ACQUIRED;
295 	}
296 	acpi_irq_irq = irq;
297 
298 	return AE_OK;
299 }
300 
301 acpi_status acpi_os_remove_interrupt_handler(u32 irq, acpi_osd_handler handler)
302 {
303 	if (irq) {
304 		free_irq(irq, acpi_irq);
305 		acpi_irq_handler = NULL;
306 		acpi_irq_irq = 0;
307 	}
308 
309 	return AE_OK;
310 }
311 
312 /*
313  * Running in interpreter thread context, safe to sleep
314  */
315 
316 void acpi_os_sleep(acpi_integer ms)
317 {
318 	schedule_timeout_interruptible(msecs_to_jiffies(ms));
319 }
320 
321 EXPORT_SYMBOL(acpi_os_sleep);
322 
323 void acpi_os_stall(u32 us)
324 {
325 	while (us) {
326 		u32 delay = 1000;
327 
328 		if (delay > us)
329 			delay = us;
330 		udelay(delay);
331 		touch_nmi_watchdog();
332 		us -= delay;
333 	}
334 }
335 
336 EXPORT_SYMBOL(acpi_os_stall);
337 
338 /*
339  * Support ACPI 3.0 AML Timer operand
340  * Returns 64-bit free-running, monotonically increasing timer
341  * with 100ns granularity
342  */
343 u64 acpi_os_get_timer(void)
344 {
345 	static u64 t;
346 
347 #ifdef	CONFIG_HPET
348 	/* TBD: use HPET if available */
349 #endif
350 
351 #ifdef	CONFIG_X86_PM_TIMER
352 	/* TBD: default to PM timer if HPET was not available */
353 #endif
354 	if (!t)
355 		printk(KERN_ERR PREFIX "acpi_os_get_timer() TBD\n");
356 
357 	return ++t;
358 }
359 
360 acpi_status acpi_os_read_port(acpi_io_address port, u32 * value, u32 width)
361 {
362 	u32 dummy;
363 
364 	if (!value)
365 		value = &dummy;
366 
367 	switch (width) {
368 	case 8:
369 		*(u8 *) value = inb(port);
370 		break;
371 	case 16:
372 		*(u16 *) value = inw(port);
373 		break;
374 	case 32:
375 		*(u32 *) value = inl(port);
376 		break;
377 	default:
378 		BUG();
379 	}
380 
381 	return AE_OK;
382 }
383 
384 EXPORT_SYMBOL(acpi_os_read_port);
385 
386 acpi_status acpi_os_write_port(acpi_io_address port, u32 value, u32 width)
387 {
388 	switch (width) {
389 	case 8:
390 		outb(value, port);
391 		break;
392 	case 16:
393 		outw(value, port);
394 		break;
395 	case 32:
396 		outl(value, port);
397 		break;
398 	default:
399 		BUG();
400 	}
401 
402 	return AE_OK;
403 }
404 
405 EXPORT_SYMBOL(acpi_os_write_port);
406 
407 acpi_status
408 acpi_os_read_memory(acpi_physical_address phys_addr, u32 * value, u32 width)
409 {
410 	u32 dummy;
411 	void __iomem *virt_addr;
412 	int iomem = 0;
413 
414 	if (efi_enabled) {
415 		if (EFI_MEMORY_WB & efi_mem_attributes(phys_addr)) {
416 			/* HACK ALERT! We can use readb/w/l on real memory too.. */
417 			virt_addr = (void __iomem *)phys_to_virt(phys_addr);
418 		} else {
419 			iomem = 1;
420 			virt_addr = ioremap(phys_addr, width);
421 		}
422 	} else
423 		virt_addr = (void __iomem *)phys_to_virt(phys_addr);
424 	if (!value)
425 		value = &dummy;
426 
427 	switch (width) {
428 	case 8:
429 		*(u8 *) value = readb(virt_addr);
430 		break;
431 	case 16:
432 		*(u16 *) value = readw(virt_addr);
433 		break;
434 	case 32:
435 		*(u32 *) value = readl(virt_addr);
436 		break;
437 	default:
438 		BUG();
439 	}
440 
441 	if (efi_enabled) {
442 		if (iomem)
443 			iounmap(virt_addr);
444 	}
445 
446 	return AE_OK;
447 }
448 
449 acpi_status
450 acpi_os_write_memory(acpi_physical_address phys_addr, u32 value, u32 width)
451 {
452 	void __iomem *virt_addr;
453 	int iomem = 0;
454 
455 	if (efi_enabled) {
456 		if (EFI_MEMORY_WB & efi_mem_attributes(phys_addr)) {
457 			/* HACK ALERT! We can use writeb/w/l on real memory too */
458 			virt_addr = (void __iomem *)phys_to_virt(phys_addr);
459 		} else {
460 			iomem = 1;
461 			virt_addr = ioremap(phys_addr, width);
462 		}
463 	} else
464 		virt_addr = (void __iomem *)phys_to_virt(phys_addr);
465 
466 	switch (width) {
467 	case 8:
468 		writeb(value, virt_addr);
469 		break;
470 	case 16:
471 		writew(value, virt_addr);
472 		break;
473 	case 32:
474 		writel(value, virt_addr);
475 		break;
476 	default:
477 		BUG();
478 	}
479 
480 	if (iomem)
481 		iounmap(virt_addr);
482 
483 	return AE_OK;
484 }
485 
486 acpi_status
487 acpi_os_read_pci_configuration(struct acpi_pci_id * pci_id, u32 reg,
488 			       void *value, u32 width)
489 {
490 	int result, size;
491 
492 	if (!value)
493 		return AE_BAD_PARAMETER;
494 
495 	switch (width) {
496 	case 8:
497 		size = 1;
498 		break;
499 	case 16:
500 		size = 2;
501 		break;
502 	case 32:
503 		size = 4;
504 		break;
505 	default:
506 		return AE_ERROR;
507 	}
508 
509 	BUG_ON(!raw_pci_ops);
510 
511 	result = raw_pci_ops->read(pci_id->segment, pci_id->bus,
512 				   PCI_DEVFN(pci_id->device, pci_id->function),
513 				   reg, size, value);
514 
515 	return (result ? AE_ERROR : AE_OK);
516 }
517 
518 EXPORT_SYMBOL(acpi_os_read_pci_configuration);
519 
520 acpi_status
521 acpi_os_write_pci_configuration(struct acpi_pci_id * pci_id, u32 reg,
522 				acpi_integer value, u32 width)
523 {
524 	int result, size;
525 
526 	switch (width) {
527 	case 8:
528 		size = 1;
529 		break;
530 	case 16:
531 		size = 2;
532 		break;
533 	case 32:
534 		size = 4;
535 		break;
536 	default:
537 		return AE_ERROR;
538 	}
539 
540 	BUG_ON(!raw_pci_ops);
541 
542 	result = raw_pci_ops->write(pci_id->segment, pci_id->bus,
543 				    PCI_DEVFN(pci_id->device, pci_id->function),
544 				    reg, size, value);
545 
546 	return (result ? AE_ERROR : AE_OK);
547 }
548 
549 /* TODO: Change code to take advantage of driver model more */
550 static void acpi_os_derive_pci_id_2(acpi_handle rhandle,	/* upper bound  */
551 				    acpi_handle chandle,	/* current node */
552 				    struct acpi_pci_id **id,
553 				    int *is_bridge, u8 * bus_number)
554 {
555 	acpi_handle handle;
556 	struct acpi_pci_id *pci_id = *id;
557 	acpi_status status;
558 	unsigned long temp;
559 	acpi_object_type type;
560 	u8 tu8;
561 
562 	acpi_get_parent(chandle, &handle);
563 	if (handle != rhandle) {
564 		acpi_os_derive_pci_id_2(rhandle, handle, &pci_id, is_bridge,
565 					bus_number);
566 
567 		status = acpi_get_type(handle, &type);
568 		if ((ACPI_FAILURE(status)) || (type != ACPI_TYPE_DEVICE))
569 			return;
570 
571 		status =
572 		    acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL,
573 					  &temp);
574 		if (ACPI_SUCCESS(status)) {
575 			pci_id->device = ACPI_HIWORD(ACPI_LODWORD(temp));
576 			pci_id->function = ACPI_LOWORD(ACPI_LODWORD(temp));
577 
578 			if (*is_bridge)
579 				pci_id->bus = *bus_number;
580 
581 			/* any nicer way to get bus number of bridge ? */
582 			status =
583 			    acpi_os_read_pci_configuration(pci_id, 0x0e, &tu8,
584 							   8);
585 			if (ACPI_SUCCESS(status)
586 			    && ((tu8 & 0x7f) == 1 || (tu8 & 0x7f) == 2)) {
587 				status =
588 				    acpi_os_read_pci_configuration(pci_id, 0x18,
589 								   &tu8, 8);
590 				if (!ACPI_SUCCESS(status)) {
591 					/* Certainly broken...  FIX ME */
592 					return;
593 				}
594 				*is_bridge = 1;
595 				pci_id->bus = tu8;
596 				status =
597 				    acpi_os_read_pci_configuration(pci_id, 0x19,
598 								   &tu8, 8);
599 				if (ACPI_SUCCESS(status)) {
600 					*bus_number = tu8;
601 				}
602 			} else
603 				*is_bridge = 0;
604 		}
605 	}
606 }
607 
608 void acpi_os_derive_pci_id(acpi_handle rhandle,	/* upper bound  */
609 			   acpi_handle chandle,	/* current node */
610 			   struct acpi_pci_id **id)
611 {
612 	int is_bridge = 1;
613 	u8 bus_number = (*id)->bus;
614 
615 	acpi_os_derive_pci_id_2(rhandle, chandle, id, &is_bridge, &bus_number);
616 }
617 
618 static void acpi_os_execute_deferred(void *context)
619 {
620 	struct acpi_os_dpc *dpc = NULL;
621 
622 	ACPI_FUNCTION_TRACE("os_execute_deferred");
623 
624 	dpc = (struct acpi_os_dpc *)context;
625 	if (!dpc) {
626 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid (NULL) context.\n"));
627 		return_VOID;
628 	}
629 
630 	dpc->function(dpc->context);
631 
632 	kfree(dpc);
633 
634 	return_VOID;
635 }
636 
637 acpi_status
638 acpi_os_queue_for_execution(u32 priority,
639 			    acpi_osd_exec_callback function, void *context)
640 {
641 	acpi_status status = AE_OK;
642 	struct acpi_os_dpc *dpc;
643 	struct work_struct *task;
644 
645 	ACPI_FUNCTION_TRACE("os_queue_for_execution");
646 
647 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
648 			  "Scheduling function [%p(%p)] for deferred execution.\n",
649 			  function, context));
650 
651 	if (!function)
652 		return_ACPI_STATUS(AE_BAD_PARAMETER);
653 
654 	/*
655 	 * Allocate/initialize DPC structure.  Note that this memory will be
656 	 * freed by the callee.  The kernel handles the tq_struct list  in a
657 	 * way that allows us to also free its memory inside the callee.
658 	 * Because we may want to schedule several tasks with different
659 	 * parameters we can't use the approach some kernel code uses of
660 	 * having a static tq_struct.
661 	 * We can save time and code by allocating the DPC and tq_structs
662 	 * from the same memory.
663 	 */
664 
665 	dpc =
666 	    kmalloc(sizeof(struct acpi_os_dpc) + sizeof(struct work_struct),
667 		    GFP_ATOMIC);
668 	if (!dpc)
669 		return_ACPI_STATUS(AE_NO_MEMORY);
670 
671 	dpc->function = function;
672 	dpc->context = context;
673 
674 	task = (void *)(dpc + 1);
675 	INIT_WORK(task, acpi_os_execute_deferred, (void *)dpc);
676 
677 	if (!queue_work(kacpid_wq, task)) {
678 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
679 				  "Call to queue_work() failed.\n"));
680 		kfree(dpc);
681 		status = AE_ERROR;
682 	}
683 
684 	return_ACPI_STATUS(status);
685 }
686 
687 EXPORT_SYMBOL(acpi_os_queue_for_execution);
688 
689 void acpi_os_wait_events_complete(void *context)
690 {
691 	flush_workqueue(kacpid_wq);
692 }
693 
694 EXPORT_SYMBOL(acpi_os_wait_events_complete);
695 
696 /*
697  * Allocate the memory for a spinlock and initialize it.
698  */
699 acpi_status acpi_os_create_lock(acpi_handle * out_handle)
700 {
701 	spinlock_t *lock_ptr;
702 
703 	ACPI_FUNCTION_TRACE("os_create_lock");
704 
705 	lock_ptr = acpi_os_allocate(sizeof(spinlock_t));
706 
707 	spin_lock_init(lock_ptr);
708 
709 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Creating spinlock[%p].\n", lock_ptr));
710 
711 	*out_handle = lock_ptr;
712 
713 	return_ACPI_STATUS(AE_OK);
714 }
715 
716 /*
717  * Deallocate the memory for a spinlock.
718  */
719 void acpi_os_delete_lock(acpi_handle handle)
720 {
721 	ACPI_FUNCTION_TRACE("os_create_lock");
722 
723 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Deleting spinlock[%p].\n", handle));
724 
725 	acpi_os_free(handle);
726 
727 	return_VOID;
728 }
729 
730 acpi_status
731 acpi_os_create_semaphore(u32 max_units, u32 initial_units, acpi_handle * handle)
732 {
733 	struct semaphore *sem = NULL;
734 
735 	ACPI_FUNCTION_TRACE("os_create_semaphore");
736 
737 	sem = acpi_os_allocate(sizeof(struct semaphore));
738 	if (!sem)
739 		return_ACPI_STATUS(AE_NO_MEMORY);
740 	memset(sem, 0, sizeof(struct semaphore));
741 
742 	sema_init(sem, initial_units);
743 
744 	*handle = (acpi_handle *) sem;
745 
746 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Creating semaphore[%p|%d].\n",
747 			  *handle, initial_units));
748 
749 	return_ACPI_STATUS(AE_OK);
750 }
751 
752 EXPORT_SYMBOL(acpi_os_create_semaphore);
753 
754 /*
755  * TODO: A better way to delete semaphores?  Linux doesn't have a
756  * 'delete_semaphore()' function -- may result in an invalid
757  * pointer dereference for non-synchronized consumers.	Should
758  * we at least check for blocked threads and signal/cancel them?
759  */
760 
761 acpi_status acpi_os_delete_semaphore(acpi_handle handle)
762 {
763 	struct semaphore *sem = (struct semaphore *)handle;
764 
765 	ACPI_FUNCTION_TRACE("os_delete_semaphore");
766 
767 	if (!sem)
768 		return_ACPI_STATUS(AE_BAD_PARAMETER);
769 
770 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Deleting semaphore[%p].\n", handle));
771 
772 	acpi_os_free(sem);
773 	sem = NULL;
774 
775 	return_ACPI_STATUS(AE_OK);
776 }
777 
778 EXPORT_SYMBOL(acpi_os_delete_semaphore);
779 
780 /*
781  * TODO: The kernel doesn't have a 'down_timeout' function -- had to
782  * improvise.  The process is to sleep for one scheduler quantum
783  * until the semaphore becomes available.  Downside is that this
784  * may result in starvation for timeout-based waits when there's
785  * lots of semaphore activity.
786  *
787  * TODO: Support for units > 1?
788  */
789 acpi_status acpi_os_wait_semaphore(acpi_handle handle, u32 units, u16 timeout)
790 {
791 	acpi_status status = AE_OK;
792 	struct semaphore *sem = (struct semaphore *)handle;
793 	int ret = 0;
794 
795 	ACPI_FUNCTION_TRACE("os_wait_semaphore");
796 
797 	if (!sem || (units < 1))
798 		return_ACPI_STATUS(AE_BAD_PARAMETER);
799 
800 	if (units > 1)
801 		return_ACPI_STATUS(AE_SUPPORT);
802 
803 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Waiting for semaphore[%p|%d|%d]\n",
804 			  handle, units, timeout));
805 
806 	if (in_atomic())
807 		timeout = 0;
808 
809 	switch (timeout) {
810 		/*
811 		 * No Wait:
812 		 * --------
813 		 * A zero timeout value indicates that we shouldn't wait - just
814 		 * acquire the semaphore if available otherwise return AE_TIME
815 		 * (a.k.a. 'would block').
816 		 */
817 	case 0:
818 		if (down_trylock(sem))
819 			status = AE_TIME;
820 		break;
821 
822 		/*
823 		 * Wait Indefinitely:
824 		 * ------------------
825 		 */
826 	case ACPI_WAIT_FOREVER:
827 		down(sem);
828 		break;
829 
830 		/*
831 		 * Wait w/ Timeout:
832 		 * ----------------
833 		 */
834 	default:
835 		// TODO: A better timeout algorithm?
836 		{
837 			int i = 0;
838 			static const int quantum_ms = 1000 / HZ;
839 
840 			ret = down_trylock(sem);
841 			for (i = timeout; (i > 0 && ret != 0); i -= quantum_ms) {
842 				schedule_timeout_interruptible(1);
843 				ret = down_trylock(sem);
844 			}
845 
846 			if (ret != 0)
847 				status = AE_TIME;
848 		}
849 		break;
850 	}
851 
852 	if (ACPI_FAILURE(status)) {
853 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
854 				  "Failed to acquire semaphore[%p|%d|%d], %s\n",
855 				  handle, units, timeout,
856 				  acpi_format_exception(status)));
857 	} else {
858 		ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
859 				  "Acquired semaphore[%p|%d|%d]\n", handle,
860 				  units, timeout));
861 	}
862 
863 	return_ACPI_STATUS(status);
864 }
865 
866 EXPORT_SYMBOL(acpi_os_wait_semaphore);
867 
868 /*
869  * TODO: Support for units > 1?
870  */
871 acpi_status acpi_os_signal_semaphore(acpi_handle handle, u32 units)
872 {
873 	struct semaphore *sem = (struct semaphore *)handle;
874 
875 	ACPI_FUNCTION_TRACE("os_signal_semaphore");
876 
877 	if (!sem || (units < 1))
878 		return_ACPI_STATUS(AE_BAD_PARAMETER);
879 
880 	if (units > 1)
881 		return_ACPI_STATUS(AE_SUPPORT);
882 
883 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Signaling semaphore[%p|%d]\n", handle,
884 			  units));
885 
886 	up(sem);
887 
888 	return_ACPI_STATUS(AE_OK);
889 }
890 
891 EXPORT_SYMBOL(acpi_os_signal_semaphore);
892 
893 #ifdef ACPI_FUTURE_USAGE
894 u32 acpi_os_get_line(char *buffer)
895 {
896 
897 #ifdef ENABLE_DEBUGGER
898 	if (acpi_in_debugger) {
899 		u32 chars;
900 
901 		kdb_read(buffer, sizeof(line_buf));
902 
903 		/* remove the CR kdb includes */
904 		chars = strlen(buffer) - 1;
905 		buffer[chars] = '\0';
906 	}
907 #endif
908 
909 	return 0;
910 }
911 #endif				/*  ACPI_FUTURE_USAGE  */
912 
913 /* Assumes no unreadable holes inbetween */
914 u8 acpi_os_readable(void *ptr, acpi_size len)
915 {
916 #if defined(__i386__) || defined(__x86_64__)
917 	char tmp;
918 	return !__get_user(tmp, (char __user *)ptr)
919 	    && !__get_user(tmp, (char __user *)ptr + len - 1);
920 #endif
921 	return 1;
922 }
923 
924 #ifdef ACPI_FUTURE_USAGE
925 u8 acpi_os_writable(void *ptr, acpi_size len)
926 {
927 	/* could do dummy write (racy) or a kernel page table lookup.
928 	   The later may be difficult at early boot when kmap doesn't work yet. */
929 	return 1;
930 }
931 #endif
932 
933 u32 acpi_os_get_thread_id(void)
934 {
935 	if (!in_atomic())
936 		return current->pid;
937 
938 	return 0;
939 }
940 
941 acpi_status acpi_os_signal(u32 function, void *info)
942 {
943 	switch (function) {
944 	case ACPI_SIGNAL_FATAL:
945 		printk(KERN_ERR PREFIX "Fatal opcode executed\n");
946 		break;
947 	case ACPI_SIGNAL_BREAKPOINT:
948 		/*
949 		 * AML Breakpoint
950 		 * ACPI spec. says to treat it as a NOP unless
951 		 * you are debugging.  So if/when we integrate
952 		 * AML debugger into the kernel debugger its
953 		 * hook will go here.  But until then it is
954 		 * not useful to print anything on breakpoints.
955 		 */
956 		break;
957 	default:
958 		break;
959 	}
960 
961 	return AE_OK;
962 }
963 
964 EXPORT_SYMBOL(acpi_os_signal);
965 
966 static int __init acpi_os_name_setup(char *str)
967 {
968 	char *p = acpi_os_name;
969 	int count = ACPI_MAX_OVERRIDE_LEN - 1;
970 
971 	if (!str || !*str)
972 		return 0;
973 
974 	for (; count-- && str && *str; str++) {
975 		if (isalnum(*str) || *str == ' ' || *str == ':')
976 			*p++ = *str;
977 		else if (*str == '\'' || *str == '"')
978 			continue;
979 		else
980 			break;
981 	}
982 	*p = 0;
983 
984 	return 1;
985 
986 }
987 
988 __setup("acpi_os_name=", acpi_os_name_setup);
989 
990 /*
991  * _OSI control
992  * empty string disables _OSI
993  * TBD additional string adds to _OSI
994  */
995 static int __init acpi_osi_setup(char *str)
996 {
997 	if (str == NULL || *str == '\0') {
998 		printk(KERN_INFO PREFIX "_OSI method disabled\n");
999 		acpi_gbl_create_osi_method = FALSE;
1000 	} else {
1001 		/* TBD */
1002 		printk(KERN_ERR PREFIX "_OSI additional string ignored -- %s\n",
1003 		       str);
1004 	}
1005 
1006 	return 1;
1007 }
1008 
1009 __setup("acpi_osi=", acpi_osi_setup);
1010 
1011 /* enable serialization to combat AE_ALREADY_EXISTS errors */
1012 static int __init acpi_serialize_setup(char *str)
1013 {
1014 	printk(KERN_INFO PREFIX "serialize enabled\n");
1015 
1016 	acpi_gbl_all_methods_serialized = TRUE;
1017 
1018 	return 1;
1019 }
1020 
1021 __setup("acpi_serialize", acpi_serialize_setup);
1022 
1023 /*
1024  * Wake and Run-Time GPES are expected to be separate.
1025  * We disable wake-GPEs at run-time to prevent spurious
1026  * interrupts.
1027  *
1028  * However, if a system exists that shares Wake and
1029  * Run-time events on the same GPE this flag is available
1030  * to tell Linux to keep the wake-time GPEs enabled at run-time.
1031  */
1032 static int __init acpi_wake_gpes_always_on_setup(char *str)
1033 {
1034 	printk(KERN_INFO PREFIX "wake GPEs not disabled\n");
1035 
1036 	acpi_gbl_leave_wake_gpes_disabled = FALSE;
1037 
1038 	return 1;
1039 }
1040 
1041 __setup("acpi_wake_gpes_always_on", acpi_wake_gpes_always_on_setup);
1042 
1043 static int __init acpi_hotkey_setup(char *str)
1044 {
1045 	acpi_specific_hotkey_enabled = FALSE;
1046 	return 1;
1047 }
1048 
1049 __setup("acpi_generic_hotkey", acpi_hotkey_setup);
1050 
1051 /*
1052  * max_cstate is defined in the base kernel so modules can
1053  * change it w/o depending on the state of the processor module.
1054  */
1055 unsigned int max_cstate = ACPI_PROCESSOR_MAX_POWER;
1056 
1057 EXPORT_SYMBOL(max_cstate);
1058 
1059 /*
1060  * Acquire a spinlock.
1061  *
1062  * handle is a pointer to the spinlock_t.
1063  */
1064 
1065 acpi_cpu_flags acpi_os_acquire_lock(acpi_handle handle)
1066 {
1067 	acpi_cpu_flags flags;
1068 	spin_lock_irqsave((spinlock_t *) handle, flags);
1069 	return flags;
1070 }
1071 
1072 /*
1073  * Release a spinlock. See above.
1074  */
1075 
1076 void acpi_os_release_lock(acpi_handle handle, acpi_cpu_flags flags)
1077 {
1078 	spin_unlock_irqrestore((spinlock_t *) handle, flags);
1079 }
1080 
1081 #ifndef ACPI_USE_LOCAL_CACHE
1082 
1083 /*******************************************************************************
1084  *
1085  * FUNCTION:    acpi_os_create_cache
1086  *
1087  * PARAMETERS:  CacheName       - Ascii name for the cache
1088  *              ObjectSize      - Size of each cached object
1089  *              MaxDepth        - Maximum depth of the cache (in objects)
1090  *              ReturnCache     - Where the new cache object is returned
1091  *
1092  * RETURN:      Status
1093  *
1094  * DESCRIPTION: Create a cache object
1095  *
1096  ******************************************************************************/
1097 
1098 acpi_status
1099 acpi_os_create_cache(char *name, u16 size, u16 depth, acpi_cache_t ** cache)
1100 {
1101 	*cache = kmem_cache_create(name, size, 0, 0, NULL, NULL);
1102 	return AE_OK;
1103 }
1104 
1105 /*******************************************************************************
1106  *
1107  * FUNCTION:    acpi_os_purge_cache
1108  *
1109  * PARAMETERS:  Cache           - Handle to cache object
1110  *
1111  * RETURN:      Status
1112  *
1113  * DESCRIPTION: Free all objects within the requested cache.
1114  *
1115  ******************************************************************************/
1116 
1117 acpi_status acpi_os_purge_cache(acpi_cache_t * cache)
1118 {
1119 	(void)kmem_cache_shrink(cache);
1120 	return (AE_OK);
1121 }
1122 
1123 /*******************************************************************************
1124  *
1125  * FUNCTION:    acpi_os_delete_cache
1126  *
1127  * PARAMETERS:  Cache           - Handle to cache object
1128  *
1129  * RETURN:      Status
1130  *
1131  * DESCRIPTION: Free all objects within the requested cache and delete the
1132  *              cache object.
1133  *
1134  ******************************************************************************/
1135 
1136 acpi_status acpi_os_delete_cache(acpi_cache_t * cache)
1137 {
1138 	(void)kmem_cache_destroy(cache);
1139 	return (AE_OK);
1140 }
1141 
1142 /*******************************************************************************
1143  *
1144  * FUNCTION:    acpi_os_release_object
1145  *
1146  * PARAMETERS:  Cache       - Handle to cache object
1147  *              Object      - The object to be released
1148  *
1149  * RETURN:      None
1150  *
1151  * DESCRIPTION: Release an object to the specified cache.  If cache is full,
1152  *              the object is deleted.
1153  *
1154  ******************************************************************************/
1155 
1156 acpi_status acpi_os_release_object(acpi_cache_t * cache, void *object)
1157 {
1158 	kmem_cache_free(cache, object);
1159 	return (AE_OK);
1160 }
1161 
1162 /*******************************************************************************
1163  *
1164  * FUNCTION:    acpi_os_acquire_object
1165  *
1166  * PARAMETERS:  Cache           - Handle to cache object
1167  *              ReturnObject    - Where the object is returned
1168  *
1169  * RETURN:      Status
1170  *
1171  * DESCRIPTION: Get an object from the specified cache.  If cache is empty,
1172  *              the object is allocated.
1173  *
1174  ******************************************************************************/
1175 
1176 void *acpi_os_acquire_object(acpi_cache_t * cache)
1177 {
1178 	void *object = kmem_cache_alloc(cache, GFP_KERNEL);
1179 	WARN_ON(!object);
1180 	return object;
1181 }
1182 
1183 #endif
1184