xref: /openbmc/linux/drivers/acpi/acpica/evregion.c (revision 565d76cb)
1 /******************************************************************************
2  *
3  * Module Name: evregion - ACPI address_space (op_region) handler dispatch
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2011, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acevents.h"
47 #include "acnamesp.h"
48 #include "acinterp.h"
49 
50 #define _COMPONENT          ACPI_EVENTS
51 ACPI_MODULE_NAME("evregion")
52 
53 /* Local prototypes */
54 static u8
55 acpi_ev_has_default_handler(struct acpi_namespace_node *node,
56 			    acpi_adr_space_type space_id);
57 
58 static acpi_status
59 acpi_ev_reg_run(acpi_handle obj_handle,
60 		u32 level, void *context, void **return_value);
61 
62 static acpi_status
63 acpi_ev_install_handler(acpi_handle obj_handle,
64 			u32 level, void *context, void **return_value);
65 
66 /* These are the address spaces that will get default handlers */
67 
68 #define ACPI_NUM_DEFAULT_SPACES     4
69 
70 static u8 acpi_gbl_default_address_spaces[ACPI_NUM_DEFAULT_SPACES] = {
71 	ACPI_ADR_SPACE_SYSTEM_MEMORY,
72 	ACPI_ADR_SPACE_SYSTEM_IO,
73 	ACPI_ADR_SPACE_PCI_CONFIG,
74 	ACPI_ADR_SPACE_DATA_TABLE
75 };
76 
77 /*******************************************************************************
78  *
79  * FUNCTION:    acpi_ev_install_region_handlers
80  *
81  * PARAMETERS:  None
82  *
83  * RETURN:      Status
84  *
85  * DESCRIPTION: Installs the core subsystem default address space handlers.
86  *
87  ******************************************************************************/
88 
89 acpi_status acpi_ev_install_region_handlers(void)
90 {
91 	acpi_status status;
92 	u32 i;
93 
94 	ACPI_FUNCTION_TRACE(ev_install_region_handlers);
95 
96 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
97 	if (ACPI_FAILURE(status)) {
98 		return_ACPI_STATUS(status);
99 	}
100 
101 	/*
102 	 * All address spaces (PCI Config, EC, SMBus) are scope dependent and
103 	 * registration must occur for a specific device.
104 	 *
105 	 * In the case of the system memory and IO address spaces there is
106 	 * currently no device associated with the address space. For these we
107 	 * use the root.
108 	 *
109 	 * We install the default PCI config space handler at the root so that
110 	 * this space is immediately available even though the we have not
111 	 * enumerated all the PCI Root Buses yet. This is to conform to the ACPI
112 	 * specification which states that the PCI config space must be always
113 	 * available -- even though we are nowhere near ready to find the PCI root
114 	 * buses at this point.
115 	 *
116 	 * NOTE: We ignore AE_ALREADY_EXISTS because this means that a handler
117 	 * has already been installed (via acpi_install_address_space_handler).
118 	 * Similar for AE_SAME_HANDLER.
119 	 */
120 	for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++) {
121 		status = acpi_ev_install_space_handler(acpi_gbl_root_node,
122 						       acpi_gbl_default_address_spaces
123 						       [i],
124 						       ACPI_DEFAULT_HANDLER,
125 						       NULL, NULL);
126 		switch (status) {
127 		case AE_OK:
128 		case AE_SAME_HANDLER:
129 		case AE_ALREADY_EXISTS:
130 
131 			/* These exceptions are all OK */
132 
133 			status = AE_OK;
134 			break;
135 
136 		default:
137 
138 			goto unlock_and_exit;
139 		}
140 	}
141 
142       unlock_and_exit:
143 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
144 	return_ACPI_STATUS(status);
145 }
146 
147 /*******************************************************************************
148  *
149  * FUNCTION:    acpi_ev_has_default_handler
150  *
151  * PARAMETERS:  Node                - Namespace node for the device
152  *              space_id            - The address space ID
153  *
154  * RETURN:      TRUE if default handler is installed, FALSE otherwise
155  *
156  * DESCRIPTION: Check if the default handler is installed for the requested
157  *              space ID.
158  *
159  ******************************************************************************/
160 
161 static u8
162 acpi_ev_has_default_handler(struct acpi_namespace_node *node,
163 			    acpi_adr_space_type space_id)
164 {
165 	union acpi_operand_object *obj_desc;
166 	union acpi_operand_object *handler_obj;
167 
168 	/* Must have an existing internal object */
169 
170 	obj_desc = acpi_ns_get_attached_object(node);
171 	if (obj_desc) {
172 		handler_obj = obj_desc->device.handler;
173 
174 		/* Walk the linked list of handlers for this object */
175 
176 		while (handler_obj) {
177 			if (handler_obj->address_space.space_id == space_id) {
178 				if (handler_obj->address_space.handler_flags &
179 				    ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
180 					return (TRUE);
181 				}
182 			}
183 
184 			handler_obj = handler_obj->address_space.next;
185 		}
186 	}
187 
188 	return (FALSE);
189 }
190 
191 /*******************************************************************************
192  *
193  * FUNCTION:    acpi_ev_initialize_op_regions
194  *
195  * PARAMETERS:  None
196  *
197  * RETURN:      Status
198  *
199  * DESCRIPTION: Execute _REG methods for all Operation Regions that have
200  *              an installed default region handler.
201  *
202  ******************************************************************************/
203 
204 acpi_status acpi_ev_initialize_op_regions(void)
205 {
206 	acpi_status status;
207 	u32 i;
208 
209 	ACPI_FUNCTION_TRACE(ev_initialize_op_regions);
210 
211 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
212 	if (ACPI_FAILURE(status)) {
213 		return_ACPI_STATUS(status);
214 	}
215 
216 	/* Run the _REG methods for op_regions in each default address space */
217 
218 	for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++) {
219 		/*
220 		 * Make sure the installed handler is the DEFAULT handler. If not the
221 		 * default, the _REG methods will have already been run (when the
222 		 * handler was installed)
223 		 */
224 		if (acpi_ev_has_default_handler(acpi_gbl_root_node,
225 						acpi_gbl_default_address_spaces
226 						[i])) {
227 			status =
228 			    acpi_ev_execute_reg_methods(acpi_gbl_root_node,
229 							acpi_gbl_default_address_spaces
230 							[i]);
231 		}
232 	}
233 
234 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
235 	return_ACPI_STATUS(status);
236 }
237 
238 /*******************************************************************************
239  *
240  * FUNCTION:    acpi_ev_execute_reg_method
241  *
242  * PARAMETERS:  region_obj          - Region object
243  *              Function            - Passed to _REG: On (1) or Off (0)
244  *
245  * RETURN:      Status
246  *
247  * DESCRIPTION: Execute _REG method for a region
248  *
249  ******************************************************************************/
250 
251 acpi_status
252 acpi_ev_execute_reg_method(union acpi_operand_object *region_obj, u32 function)
253 {
254 	struct acpi_evaluate_info *info;
255 	union acpi_operand_object *args[3];
256 	union acpi_operand_object *region_obj2;
257 	acpi_status status;
258 
259 	ACPI_FUNCTION_TRACE(ev_execute_reg_method);
260 
261 	region_obj2 = acpi_ns_get_secondary_object(region_obj);
262 	if (!region_obj2) {
263 		return_ACPI_STATUS(AE_NOT_EXIST);
264 	}
265 
266 	if (region_obj2->extra.method_REG == NULL) {
267 		return_ACPI_STATUS(AE_OK);
268 	}
269 
270 	/* Allocate and initialize the evaluation information block */
271 
272 	info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
273 	if (!info) {
274 		return_ACPI_STATUS(AE_NO_MEMORY);
275 	}
276 
277 	info->prefix_node = region_obj2->extra.method_REG;
278 	info->pathname = NULL;
279 	info->parameters = args;
280 	info->flags = ACPI_IGNORE_RETURN_VALUE;
281 
282 	/*
283 	 * The _REG method has two arguments:
284 	 *
285 	 * Arg0 - Integer:
286 	 *  Operation region space ID Same value as region_obj->Region.space_id
287 	 *
288 	 * Arg1 - Integer:
289 	 *  connection status 1 for connecting the handler, 0 for disconnecting
290 	 *  the handler (Passed as a parameter)
291 	 */
292 	args[0] =
293 	    acpi_ut_create_integer_object((u64) region_obj->region.space_id);
294 	if (!args[0]) {
295 		status = AE_NO_MEMORY;
296 		goto cleanup1;
297 	}
298 
299 	args[1] = acpi_ut_create_integer_object((u64) function);
300 	if (!args[1]) {
301 		status = AE_NO_MEMORY;
302 		goto cleanup2;
303 	}
304 
305 	args[2] = NULL;		/* Terminate list */
306 
307 	/* Execute the method, no return value */
308 
309 	ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
310 			(ACPI_TYPE_METHOD, info->prefix_node, NULL));
311 
312 	status = acpi_ns_evaluate(info);
313 	acpi_ut_remove_reference(args[1]);
314 
315       cleanup2:
316 	acpi_ut_remove_reference(args[0]);
317 
318       cleanup1:
319 	ACPI_FREE(info);
320 	return_ACPI_STATUS(status);
321 }
322 
323 /*******************************************************************************
324  *
325  * FUNCTION:    acpi_ev_address_space_dispatch
326  *
327  * PARAMETERS:  region_obj          - Internal region object
328  *              Function            - Read or Write operation
329  *              region_offset       - Where in the region to read or write
330  *              bit_width           - Field width in bits (8, 16, 32, or 64)
331  *              Value               - Pointer to in or out value, must be
332  *                                    a full 64-bit integer
333  *
334  * RETURN:      Status
335  *
336  * DESCRIPTION: Dispatch an address space or operation region access to
337  *              a previously installed handler.
338  *
339  ******************************************************************************/
340 
341 acpi_status
342 acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj,
343 			       u32 function,
344 			       u32 region_offset, u32 bit_width, u64 *value)
345 {
346 	acpi_status status;
347 	acpi_adr_space_handler handler;
348 	acpi_adr_space_setup region_setup;
349 	union acpi_operand_object *handler_desc;
350 	union acpi_operand_object *region_obj2;
351 	void *region_context = NULL;
352 
353 	ACPI_FUNCTION_TRACE(ev_address_space_dispatch);
354 
355 	region_obj2 = acpi_ns_get_secondary_object(region_obj);
356 	if (!region_obj2) {
357 		return_ACPI_STATUS(AE_NOT_EXIST);
358 	}
359 
360 	/* Ensure that there is a handler associated with this region */
361 
362 	handler_desc = region_obj->region.handler;
363 	if (!handler_desc) {
364 		ACPI_ERROR((AE_INFO,
365 			    "No handler for Region [%4.4s] (%p) [%s]",
366 			    acpi_ut_get_node_name(region_obj->region.node),
367 			    region_obj,
368 			    acpi_ut_get_region_name(region_obj->region.
369 						    space_id)));
370 
371 		return_ACPI_STATUS(AE_NOT_EXIST);
372 	}
373 
374 	/*
375 	 * It may be the case that the region has never been initialized.
376 	 * Some types of regions require special init code
377 	 */
378 	if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
379 
380 		/* This region has not been initialized yet, do it */
381 
382 		region_setup = handler_desc->address_space.setup;
383 		if (!region_setup) {
384 
385 			/* No initialization routine, exit with error */
386 
387 			ACPI_ERROR((AE_INFO,
388 				    "No init routine for region(%p) [%s]",
389 				    region_obj,
390 				    acpi_ut_get_region_name(region_obj->region.
391 							    space_id)));
392 			return_ACPI_STATUS(AE_NOT_EXIST);
393 		}
394 
395 		/*
396 		 * We must exit the interpreter because the region setup will
397 		 * potentially execute control methods (for example, the _REG method
398 		 * for this region)
399 		 */
400 		acpi_ex_exit_interpreter();
401 
402 		status = region_setup(region_obj, ACPI_REGION_ACTIVATE,
403 				      handler_desc->address_space.context,
404 				      &region_context);
405 
406 		/* Re-enter the interpreter */
407 
408 		acpi_ex_enter_interpreter();
409 
410 		/* Check for failure of the Region Setup */
411 
412 		if (ACPI_FAILURE(status)) {
413 			ACPI_EXCEPTION((AE_INFO, status,
414 					"During region initialization: [%s]",
415 					acpi_ut_get_region_name(region_obj->
416 								region.
417 								space_id)));
418 			return_ACPI_STATUS(status);
419 		}
420 
421 		/* Region initialization may have been completed by region_setup */
422 
423 		if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
424 			region_obj->region.flags |= AOPOBJ_SETUP_COMPLETE;
425 
426 			if (region_obj2->extra.region_context) {
427 
428 				/* The handler for this region was already installed */
429 
430 				ACPI_FREE(region_context);
431 			} else {
432 				/*
433 				 * Save the returned context for use in all accesses to
434 				 * this particular region
435 				 */
436 				region_obj2->extra.region_context =
437 				    region_context;
438 			}
439 		}
440 	}
441 
442 	/* We have everything we need, we can invoke the address space handler */
443 
444 	handler = handler_desc->address_space.handler;
445 
446 	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
447 			  "Handler %p (@%p) Address %8.8X%8.8X [%s]\n",
448 			  &region_obj->region.handler->address_space, handler,
449 			  ACPI_FORMAT_NATIVE_UINT(region_obj->region.address +
450 						  region_offset),
451 			  acpi_ut_get_region_name(region_obj->region.
452 						  space_id)));
453 
454 	if (!(handler_desc->address_space.handler_flags &
455 	      ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
456 		/*
457 		 * For handlers other than the default (supplied) handlers, we must
458 		 * exit the interpreter because the handler *might* block -- we don't
459 		 * know what it will do, so we can't hold the lock on the intepreter.
460 		 */
461 		acpi_ex_exit_interpreter();
462 	}
463 
464 	/* Call the handler */
465 
466 	status = handler(function,
467 			 (region_obj->region.address + region_offset),
468 			 bit_width, value, handler_desc->address_space.context,
469 			 region_obj2->extra.region_context);
470 
471 	if (ACPI_FAILURE(status)) {
472 		ACPI_EXCEPTION((AE_INFO, status, "Returned by Handler for [%s]",
473 				acpi_ut_get_region_name(region_obj->region.
474 							space_id)));
475 	}
476 
477 	if (!(handler_desc->address_space.handler_flags &
478 	      ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
479 		/*
480 		 * We just returned from a non-default handler, we must re-enter the
481 		 * interpreter
482 		 */
483 		acpi_ex_enter_interpreter();
484 	}
485 
486 	return_ACPI_STATUS(status);
487 }
488 
489 /*******************************************************************************
490  *
491  * FUNCTION:    acpi_ev_detach_region
492  *
493  * PARAMETERS:  region_obj          - Region Object
494  *              acpi_ns_is_locked   - Namespace Region Already Locked?
495  *
496  * RETURN:      None
497  *
498  * DESCRIPTION: Break the association between the handler and the region
499  *              this is a two way association.
500  *
501  ******************************************************************************/
502 
503 void
504 acpi_ev_detach_region(union acpi_operand_object *region_obj,
505 		      u8 acpi_ns_is_locked)
506 {
507 	union acpi_operand_object *handler_obj;
508 	union acpi_operand_object *obj_desc;
509 	union acpi_operand_object **last_obj_ptr;
510 	acpi_adr_space_setup region_setup;
511 	void **region_context;
512 	union acpi_operand_object *region_obj2;
513 	acpi_status status;
514 
515 	ACPI_FUNCTION_TRACE(ev_detach_region);
516 
517 	region_obj2 = acpi_ns_get_secondary_object(region_obj);
518 	if (!region_obj2) {
519 		return_VOID;
520 	}
521 	region_context = &region_obj2->extra.region_context;
522 
523 	/* Get the address handler from the region object */
524 
525 	handler_obj = region_obj->region.handler;
526 	if (!handler_obj) {
527 
528 		/* This region has no handler, all done */
529 
530 		return_VOID;
531 	}
532 
533 	/* Find this region in the handler's list */
534 
535 	obj_desc = handler_obj->address_space.region_list;
536 	last_obj_ptr = &handler_obj->address_space.region_list;
537 
538 	while (obj_desc) {
539 
540 		/* Is this the correct Region? */
541 
542 		if (obj_desc == region_obj) {
543 			ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
544 					  "Removing Region %p from address handler %p\n",
545 					  region_obj, handler_obj));
546 
547 			/* This is it, remove it from the handler's list */
548 
549 			*last_obj_ptr = obj_desc->region.next;
550 			obj_desc->region.next = NULL;	/* Must clear field */
551 
552 			if (acpi_ns_is_locked) {
553 				status =
554 				    acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
555 				if (ACPI_FAILURE(status)) {
556 					return_VOID;
557 				}
558 			}
559 
560 			/* Now stop region accesses by executing the _REG method */
561 
562 			status = acpi_ev_execute_reg_method(region_obj, 0);
563 			if (ACPI_FAILURE(status)) {
564 				ACPI_EXCEPTION((AE_INFO, status,
565 						"from region _REG, [%s]",
566 						acpi_ut_get_region_name
567 						(region_obj->region.space_id)));
568 			}
569 
570 			if (acpi_ns_is_locked) {
571 				status =
572 				    acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
573 				if (ACPI_FAILURE(status)) {
574 					return_VOID;
575 				}
576 			}
577 
578 			/*
579 			 * If the region has been activated, call the setup handler with
580 			 * the deactivate notification
581 			 */
582 			if (region_obj->region.flags & AOPOBJ_SETUP_COMPLETE) {
583 				region_setup = handler_obj->address_space.setup;
584 				status =
585 				    region_setup(region_obj,
586 						 ACPI_REGION_DEACTIVATE,
587 						 handler_obj->address_space.
588 						 context, region_context);
589 
590 				/* Init routine may fail, Just ignore errors */
591 
592 				if (ACPI_FAILURE(status)) {
593 					ACPI_EXCEPTION((AE_INFO, status,
594 							"from region handler - deactivate, [%s]",
595 							acpi_ut_get_region_name
596 							(region_obj->region.
597 							 space_id)));
598 				}
599 
600 				region_obj->region.flags &=
601 				    ~(AOPOBJ_SETUP_COMPLETE);
602 			}
603 
604 			/*
605 			 * Remove handler reference in the region
606 			 *
607 			 * NOTE: this doesn't mean that the region goes away, the region
608 			 * is just inaccessible as indicated to the _REG method
609 			 *
610 			 * If the region is on the handler's list, this must be the
611 			 * region's handler
612 			 */
613 			region_obj->region.handler = NULL;
614 			acpi_ut_remove_reference(handler_obj);
615 
616 			return_VOID;
617 		}
618 
619 		/* Walk the linked list of handlers */
620 
621 		last_obj_ptr = &obj_desc->region.next;
622 		obj_desc = obj_desc->region.next;
623 	}
624 
625 	/* If we get here, the region was not in the handler's region list */
626 
627 	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
628 			  "Cannot remove region %p from address handler %p\n",
629 			  region_obj, handler_obj));
630 
631 	return_VOID;
632 }
633 
634 /*******************************************************************************
635  *
636  * FUNCTION:    acpi_ev_attach_region
637  *
638  * PARAMETERS:  handler_obj         - Handler Object
639  *              region_obj          - Region Object
640  *              acpi_ns_is_locked   - Namespace Region Already Locked?
641  *
642  * RETURN:      None
643  *
644  * DESCRIPTION: Create the association between the handler and the region
645  *              this is a two way association.
646  *
647  ******************************************************************************/
648 
649 acpi_status
650 acpi_ev_attach_region(union acpi_operand_object *handler_obj,
651 		      union acpi_operand_object *region_obj,
652 		      u8 acpi_ns_is_locked)
653 {
654 
655 	ACPI_FUNCTION_TRACE(ev_attach_region);
656 
657 	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
658 			  "Adding Region [%4.4s] %p to address handler %p [%s]\n",
659 			  acpi_ut_get_node_name(region_obj->region.node),
660 			  region_obj, handler_obj,
661 			  acpi_ut_get_region_name(region_obj->region.
662 						  space_id)));
663 
664 	/* Link this region to the front of the handler's list */
665 
666 	region_obj->region.next = handler_obj->address_space.region_list;
667 	handler_obj->address_space.region_list = region_obj;
668 
669 	/* Install the region's handler */
670 
671 	if (region_obj->region.handler) {
672 		return_ACPI_STATUS(AE_ALREADY_EXISTS);
673 	}
674 
675 	region_obj->region.handler = handler_obj;
676 	acpi_ut_add_reference(handler_obj);
677 
678 	return_ACPI_STATUS(AE_OK);
679 }
680 
681 /*******************************************************************************
682  *
683  * FUNCTION:    acpi_ev_install_handler
684  *
685  * PARAMETERS:  walk_namespace callback
686  *
687  * DESCRIPTION: This routine installs an address handler into objects that are
688  *              of type Region or Device.
689  *
690  *              If the Object is a Device, and the device has a handler of
691  *              the same type then the search is terminated in that branch.
692  *
693  *              This is because the existing handler is closer in proximity
694  *              to any more regions than the one we are trying to install.
695  *
696  ******************************************************************************/
697 
698 static acpi_status
699 acpi_ev_install_handler(acpi_handle obj_handle,
700 			u32 level, void *context, void **return_value)
701 {
702 	union acpi_operand_object *handler_obj;
703 	union acpi_operand_object *next_handler_obj;
704 	union acpi_operand_object *obj_desc;
705 	struct acpi_namespace_node *node;
706 	acpi_status status;
707 
708 	ACPI_FUNCTION_NAME(ev_install_handler);
709 
710 	handler_obj = (union acpi_operand_object *)context;
711 
712 	/* Parameter validation */
713 
714 	if (!handler_obj) {
715 		return (AE_OK);
716 	}
717 
718 	/* Convert and validate the device handle */
719 
720 	node = acpi_ns_validate_handle(obj_handle);
721 	if (!node) {
722 		return (AE_BAD_PARAMETER);
723 	}
724 
725 	/*
726 	 * We only care about regions and objects that are allowed to have
727 	 * address space handlers
728 	 */
729 	if ((node->type != ACPI_TYPE_DEVICE) &&
730 	    (node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
731 		return (AE_OK);
732 	}
733 
734 	/* Check for an existing internal object */
735 
736 	obj_desc = acpi_ns_get_attached_object(node);
737 	if (!obj_desc) {
738 
739 		/* No object, just exit */
740 
741 		return (AE_OK);
742 	}
743 
744 	/* Devices are handled different than regions */
745 
746 	if (obj_desc->common.type == ACPI_TYPE_DEVICE) {
747 
748 		/* Check if this Device already has a handler for this address space */
749 
750 		next_handler_obj = obj_desc->device.handler;
751 		while (next_handler_obj) {
752 
753 			/* Found a handler, is it for the same address space? */
754 
755 			if (next_handler_obj->address_space.space_id ==
756 			    handler_obj->address_space.space_id) {
757 				ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
758 						  "Found handler for region [%s] in device %p(%p) "
759 						  "handler %p\n",
760 						  acpi_ut_get_region_name
761 						  (handler_obj->address_space.
762 						   space_id), obj_desc,
763 						  next_handler_obj,
764 						  handler_obj));
765 
766 				/*
767 				 * Since the object we found it on was a device, then it
768 				 * means that someone has already installed a handler for
769 				 * the branch of the namespace from this device on. Just
770 				 * bail out telling the walk routine to not traverse this
771 				 * branch. This preserves the scoping rule for handlers.
772 				 */
773 				return (AE_CTRL_DEPTH);
774 			}
775 
776 			/* Walk the linked list of handlers attached to this device */
777 
778 			next_handler_obj = next_handler_obj->address_space.next;
779 		}
780 
781 		/*
782 		 * As long as the device didn't have a handler for this space we
783 		 * don't care about it. We just ignore it and proceed.
784 		 */
785 		return (AE_OK);
786 	}
787 
788 	/* Object is a Region */
789 
790 	if (obj_desc->region.space_id != handler_obj->address_space.space_id) {
791 
792 		/* This region is for a different address space, just ignore it */
793 
794 		return (AE_OK);
795 	}
796 
797 	/*
798 	 * Now we have a region and it is for the handler's address space type.
799 	 *
800 	 * First disconnect region for any previous handler (if any)
801 	 */
802 	acpi_ev_detach_region(obj_desc, FALSE);
803 
804 	/* Connect the region to the new handler */
805 
806 	status = acpi_ev_attach_region(handler_obj, obj_desc, FALSE);
807 	return (status);
808 }
809 
810 /*******************************************************************************
811  *
812  * FUNCTION:    acpi_ev_install_space_handler
813  *
814  * PARAMETERS:  Node            - Namespace node for the device
815  *              space_id        - The address space ID
816  *              Handler         - Address of the handler
817  *              Setup           - Address of the setup function
818  *              Context         - Value passed to the handler on each access
819  *
820  * RETURN:      Status
821  *
822  * DESCRIPTION: Install a handler for all op_regions of a given space_id.
823  *              Assumes namespace is locked
824  *
825  ******************************************************************************/
826 
827 acpi_status
828 acpi_ev_install_space_handler(struct acpi_namespace_node * node,
829 			      acpi_adr_space_type space_id,
830 			      acpi_adr_space_handler handler,
831 			      acpi_adr_space_setup setup, void *context)
832 {
833 	union acpi_operand_object *obj_desc;
834 	union acpi_operand_object *handler_obj;
835 	acpi_status status;
836 	acpi_object_type type;
837 	u8 flags = 0;
838 
839 	ACPI_FUNCTION_TRACE(ev_install_space_handler);
840 
841 	/*
842 	 * This registration is valid for only the types below and the root. This
843 	 * is where the default handlers get placed.
844 	 */
845 	if ((node->type != ACPI_TYPE_DEVICE) &&
846 	    (node->type != ACPI_TYPE_PROCESSOR) &&
847 	    (node->type != ACPI_TYPE_THERMAL) && (node != acpi_gbl_root_node)) {
848 		status = AE_BAD_PARAMETER;
849 		goto unlock_and_exit;
850 	}
851 
852 	if (handler == ACPI_DEFAULT_HANDLER) {
853 		flags = ACPI_ADDR_HANDLER_DEFAULT_INSTALLED;
854 
855 		switch (space_id) {
856 		case ACPI_ADR_SPACE_SYSTEM_MEMORY:
857 			handler = acpi_ex_system_memory_space_handler;
858 			setup = acpi_ev_system_memory_region_setup;
859 			break;
860 
861 		case ACPI_ADR_SPACE_SYSTEM_IO:
862 			handler = acpi_ex_system_io_space_handler;
863 			setup = acpi_ev_io_space_region_setup;
864 			break;
865 
866 		case ACPI_ADR_SPACE_PCI_CONFIG:
867 			handler = acpi_ex_pci_config_space_handler;
868 			setup = acpi_ev_pci_config_region_setup;
869 			break;
870 
871 		case ACPI_ADR_SPACE_CMOS:
872 			handler = acpi_ex_cmos_space_handler;
873 			setup = acpi_ev_cmos_region_setup;
874 			break;
875 
876 		case ACPI_ADR_SPACE_PCI_BAR_TARGET:
877 			handler = acpi_ex_pci_bar_space_handler;
878 			setup = acpi_ev_pci_bar_region_setup;
879 			break;
880 
881 		case ACPI_ADR_SPACE_DATA_TABLE:
882 			handler = acpi_ex_data_table_space_handler;
883 			setup = NULL;
884 			break;
885 
886 		default:
887 			status = AE_BAD_PARAMETER;
888 			goto unlock_and_exit;
889 		}
890 	}
891 
892 	/* If the caller hasn't specified a setup routine, use the default */
893 
894 	if (!setup) {
895 		setup = acpi_ev_default_region_setup;
896 	}
897 
898 	/* Check for an existing internal object */
899 
900 	obj_desc = acpi_ns_get_attached_object(node);
901 	if (obj_desc) {
902 		/*
903 		 * The attached device object already exists. Make sure the handler
904 		 * is not already installed.
905 		 */
906 		handler_obj = obj_desc->device.handler;
907 
908 		/* Walk the handler list for this device */
909 
910 		while (handler_obj) {
911 
912 			/* Same space_id indicates a handler already installed */
913 
914 			if (handler_obj->address_space.space_id == space_id) {
915 				if (handler_obj->address_space.handler ==
916 				    handler) {
917 					/*
918 					 * It is (relatively) OK to attempt to install the SAME
919 					 * handler twice. This can easily happen with the
920 					 * PCI_Config space.
921 					 */
922 					status = AE_SAME_HANDLER;
923 					goto unlock_and_exit;
924 				} else {
925 					/* A handler is already installed */
926 
927 					status = AE_ALREADY_EXISTS;
928 				}
929 				goto unlock_and_exit;
930 			}
931 
932 			/* Walk the linked list of handlers */
933 
934 			handler_obj = handler_obj->address_space.next;
935 		}
936 	} else {
937 		ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
938 				  "Creating object on Device %p while installing handler\n",
939 				  node));
940 
941 		/* obj_desc does not exist, create one */
942 
943 		if (node->type == ACPI_TYPE_ANY) {
944 			type = ACPI_TYPE_DEVICE;
945 		} else {
946 			type = node->type;
947 		}
948 
949 		obj_desc = acpi_ut_create_internal_object(type);
950 		if (!obj_desc) {
951 			status = AE_NO_MEMORY;
952 			goto unlock_and_exit;
953 		}
954 
955 		/* Init new descriptor */
956 
957 		obj_desc->common.type = (u8) type;
958 
959 		/* Attach the new object to the Node */
960 
961 		status = acpi_ns_attach_object(node, obj_desc, type);
962 
963 		/* Remove local reference to the object */
964 
965 		acpi_ut_remove_reference(obj_desc);
966 
967 		if (ACPI_FAILURE(status)) {
968 			goto unlock_and_exit;
969 		}
970 	}
971 
972 	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
973 			  "Installing address handler for region %s(%X) on Device %4.4s %p(%p)\n",
974 			  acpi_ut_get_region_name(space_id), space_id,
975 			  acpi_ut_get_node_name(node), node, obj_desc));
976 
977 	/*
978 	 * Install the handler
979 	 *
980 	 * At this point there is no existing handler. Just allocate the object
981 	 * for the handler and link it into the list.
982 	 */
983 	handler_obj =
984 	    acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_ADDRESS_HANDLER);
985 	if (!handler_obj) {
986 		status = AE_NO_MEMORY;
987 		goto unlock_and_exit;
988 	}
989 
990 	/* Init handler obj */
991 
992 	handler_obj->address_space.space_id = (u8) space_id;
993 	handler_obj->address_space.handler_flags = flags;
994 	handler_obj->address_space.region_list = NULL;
995 	handler_obj->address_space.node = node;
996 	handler_obj->address_space.handler = handler;
997 	handler_obj->address_space.context = context;
998 	handler_obj->address_space.setup = setup;
999 
1000 	/* Install at head of Device.address_space list */
1001 
1002 	handler_obj->address_space.next = obj_desc->device.handler;
1003 
1004 	/*
1005 	 * The Device object is the first reference on the handler_obj.
1006 	 * Each region that uses the handler adds a reference.
1007 	 */
1008 	obj_desc->device.handler = handler_obj;
1009 
1010 	/*
1011 	 * Walk the namespace finding all of the regions this
1012 	 * handler will manage.
1013 	 *
1014 	 * Start at the device and search the branch toward
1015 	 * the leaf nodes until either the leaf is encountered or
1016 	 * a device is detected that has an address handler of the
1017 	 * same type.
1018 	 *
1019 	 * In either case, back up and search down the remainder
1020 	 * of the branch
1021 	 */
1022 	status = acpi_ns_walk_namespace(ACPI_TYPE_ANY, node, ACPI_UINT32_MAX,
1023 					ACPI_NS_WALK_UNLOCK,
1024 					acpi_ev_install_handler, NULL,
1025 					handler_obj, NULL);
1026 
1027       unlock_and_exit:
1028 	return_ACPI_STATUS(status);
1029 }
1030 
1031 /*******************************************************************************
1032  *
1033  * FUNCTION:    acpi_ev_execute_reg_methods
1034  *
1035  * PARAMETERS:  Node            - Namespace node for the device
1036  *              space_id        - The address space ID
1037  *
1038  * RETURN:      Status
1039  *
1040  * DESCRIPTION: Run all _REG methods for the input Space ID;
1041  *              Note: assumes namespace is locked, or system init time.
1042  *
1043  ******************************************************************************/
1044 
1045 acpi_status
1046 acpi_ev_execute_reg_methods(struct acpi_namespace_node *node,
1047 			    acpi_adr_space_type space_id)
1048 {
1049 	acpi_status status;
1050 
1051 	ACPI_FUNCTION_TRACE(ev_execute_reg_methods);
1052 
1053 	/*
1054 	 * Run all _REG methods for all Operation Regions for this space ID. This
1055 	 * is a separate walk in order to handle any interdependencies between
1056 	 * regions and _REG methods. (i.e. handlers must be installed for all
1057 	 * regions of this Space ID before we can run any _REG methods)
1058 	 */
1059 	status = acpi_ns_walk_namespace(ACPI_TYPE_ANY, node, ACPI_UINT32_MAX,
1060 					ACPI_NS_WALK_UNLOCK, acpi_ev_reg_run,
1061 					NULL, &space_id, NULL);
1062 
1063 	return_ACPI_STATUS(status);
1064 }
1065 
1066 /*******************************************************************************
1067  *
1068  * FUNCTION:    acpi_ev_reg_run
1069  *
1070  * PARAMETERS:  walk_namespace callback
1071  *
1072  * DESCRIPTION: Run _REG method for region objects of the requested space_iD
1073  *
1074  ******************************************************************************/
1075 
1076 static acpi_status
1077 acpi_ev_reg_run(acpi_handle obj_handle,
1078 		u32 level, void *context, void **return_value)
1079 {
1080 	union acpi_operand_object *obj_desc;
1081 	struct acpi_namespace_node *node;
1082 	acpi_adr_space_type space_id;
1083 	acpi_status status;
1084 
1085 	space_id = *ACPI_CAST_PTR(acpi_adr_space_type, context);
1086 
1087 	/* Convert and validate the device handle */
1088 
1089 	node = acpi_ns_validate_handle(obj_handle);
1090 	if (!node) {
1091 		return (AE_BAD_PARAMETER);
1092 	}
1093 
1094 	/*
1095 	 * We only care about regions.and objects that are allowed to have address
1096 	 * space handlers
1097 	 */
1098 	if ((node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
1099 		return (AE_OK);
1100 	}
1101 
1102 	/* Check for an existing internal object */
1103 
1104 	obj_desc = acpi_ns_get_attached_object(node);
1105 	if (!obj_desc) {
1106 
1107 		/* No object, just exit */
1108 
1109 		return (AE_OK);
1110 	}
1111 
1112 	/* Object is a Region */
1113 
1114 	if (obj_desc->region.space_id != space_id) {
1115 
1116 		/* This region is for a different address space, just ignore it */
1117 
1118 		return (AE_OK);
1119 	}
1120 
1121 	status = acpi_ev_execute_reg_method(obj_desc, 1);
1122 	return (status);
1123 }
1124