xref: /openbmc/linux/drivers/acpi/acpica/evregion.c (revision 63dc02bd)
1 /******************************************************************************
2  *
3  * Module Name: evregion - ACPI address_space (op_region) handler dispatch
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2012, 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 void acpi_ev_orphan_ec_reg_method(void);
59 
60 static acpi_status
61 acpi_ev_reg_run(acpi_handle obj_handle,
62 		u32 level, void *context, void **return_value);
63 
64 static acpi_status
65 acpi_ev_install_handler(acpi_handle obj_handle,
66 			u32 level, void *context, void **return_value);
67 
68 /* These are the address spaces that will get default handlers */
69 
70 #define ACPI_NUM_DEFAULT_SPACES     4
71 
72 static u8 acpi_gbl_default_address_spaces[ACPI_NUM_DEFAULT_SPACES] = {
73 	ACPI_ADR_SPACE_SYSTEM_MEMORY,
74 	ACPI_ADR_SPACE_SYSTEM_IO,
75 	ACPI_ADR_SPACE_PCI_CONFIG,
76 	ACPI_ADR_SPACE_DATA_TABLE
77 };
78 
79 /*******************************************************************************
80  *
81  * FUNCTION:    acpi_ev_install_region_handlers
82  *
83  * PARAMETERS:  None
84  *
85  * RETURN:      Status
86  *
87  * DESCRIPTION: Installs the core subsystem default address space handlers.
88  *
89  ******************************************************************************/
90 
91 acpi_status acpi_ev_install_region_handlers(void)
92 {
93 	acpi_status status;
94 	u32 i;
95 
96 	ACPI_FUNCTION_TRACE(ev_install_region_handlers);
97 
98 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
99 	if (ACPI_FAILURE(status)) {
100 		return_ACPI_STATUS(status);
101 	}
102 
103 	/*
104 	 * All address spaces (PCI Config, EC, SMBus) are scope dependent and
105 	 * registration must occur for a specific device.
106 	 *
107 	 * In the case of the system memory and IO address spaces there is
108 	 * currently no device associated with the address space. For these we
109 	 * use the root.
110 	 *
111 	 * We install the default PCI config space handler at the root so that
112 	 * this space is immediately available even though the we have not
113 	 * enumerated all the PCI Root Buses yet. This is to conform to the ACPI
114 	 * specification which states that the PCI config space must be always
115 	 * available -- even though we are nowhere near ready to find the PCI root
116 	 * buses at this point.
117 	 *
118 	 * NOTE: We ignore AE_ALREADY_EXISTS because this means that a handler
119 	 * has already been installed (via acpi_install_address_space_handler).
120 	 * Similar for AE_SAME_HANDLER.
121 	 */
122 	for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++) {
123 		status = acpi_ev_install_space_handler(acpi_gbl_root_node,
124 						       acpi_gbl_default_address_spaces
125 						       [i],
126 						       ACPI_DEFAULT_HANDLER,
127 						       NULL, NULL);
128 		switch (status) {
129 		case AE_OK:
130 		case AE_SAME_HANDLER:
131 		case AE_ALREADY_EXISTS:
132 
133 			/* These exceptions are all OK */
134 
135 			status = AE_OK;
136 			break;
137 
138 		default:
139 
140 			goto unlock_and_exit;
141 		}
142 	}
143 
144       unlock_and_exit:
145 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
146 	return_ACPI_STATUS(status);
147 }
148 
149 /*******************************************************************************
150  *
151  * FUNCTION:    acpi_ev_has_default_handler
152  *
153  * PARAMETERS:  Node                - Namespace node for the device
154  *              space_id            - The address space ID
155  *
156  * RETURN:      TRUE if default handler is installed, FALSE otherwise
157  *
158  * DESCRIPTION: Check if the default handler is installed for the requested
159  *              space ID.
160  *
161  ******************************************************************************/
162 
163 static u8
164 acpi_ev_has_default_handler(struct acpi_namespace_node *node,
165 			    acpi_adr_space_type space_id)
166 {
167 	union acpi_operand_object *obj_desc;
168 	union acpi_operand_object *handler_obj;
169 
170 	/* Must have an existing internal object */
171 
172 	obj_desc = acpi_ns_get_attached_object(node);
173 	if (obj_desc) {
174 		handler_obj = obj_desc->device.handler;
175 
176 		/* Walk the linked list of handlers for this object */
177 
178 		while (handler_obj) {
179 			if (handler_obj->address_space.space_id == space_id) {
180 				if (handler_obj->address_space.handler_flags &
181 				    ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
182 					return (TRUE);
183 				}
184 			}
185 
186 			handler_obj = handler_obj->address_space.next;
187 		}
188 	}
189 
190 	return (FALSE);
191 }
192 
193 /*******************************************************************************
194  *
195  * FUNCTION:    acpi_ev_initialize_op_regions
196  *
197  * PARAMETERS:  None
198  *
199  * RETURN:      Status
200  *
201  * DESCRIPTION: Execute _REG methods for all Operation Regions that have
202  *              an installed default region handler.
203  *
204  ******************************************************************************/
205 
206 acpi_status acpi_ev_initialize_op_regions(void)
207 {
208 	acpi_status status;
209 	u32 i;
210 
211 	ACPI_FUNCTION_TRACE(ev_initialize_op_regions);
212 
213 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
214 	if (ACPI_FAILURE(status)) {
215 		return_ACPI_STATUS(status);
216 	}
217 
218 	/* Run the _REG methods for op_regions in each default address space */
219 
220 	for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++) {
221 		/*
222 		 * Make sure the installed handler is the DEFAULT handler. If not the
223 		 * default, the _REG methods will have already been run (when the
224 		 * handler was installed)
225 		 */
226 		if (acpi_ev_has_default_handler(acpi_gbl_root_node,
227 						acpi_gbl_default_address_spaces
228 						[i])) {
229 			status =
230 			    acpi_ev_execute_reg_methods(acpi_gbl_root_node,
231 							acpi_gbl_default_address_spaces
232 							[i]);
233 		}
234 	}
235 
236 	acpi_gbl_reg_methods_executed = TRUE;
237 
238 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
239 	return_ACPI_STATUS(status);
240 }
241 
242 /*******************************************************************************
243  *
244  * FUNCTION:    acpi_ev_execute_reg_method
245  *
246  * PARAMETERS:  region_obj          - Region object
247  *              Function            - Passed to _REG: On (1) or Off (0)
248  *
249  * RETURN:      Status
250  *
251  * DESCRIPTION: Execute _REG method for a region
252  *
253  ******************************************************************************/
254 
255 acpi_status
256 acpi_ev_execute_reg_method(union acpi_operand_object *region_obj, u32 function)
257 {
258 	struct acpi_evaluate_info *info;
259 	union acpi_operand_object *args[3];
260 	union acpi_operand_object *region_obj2;
261 	acpi_status status;
262 
263 	ACPI_FUNCTION_TRACE(ev_execute_reg_method);
264 
265 	region_obj2 = acpi_ns_get_secondary_object(region_obj);
266 	if (!region_obj2) {
267 		return_ACPI_STATUS(AE_NOT_EXIST);
268 	}
269 
270 	if (region_obj2->extra.method_REG == NULL) {
271 		return_ACPI_STATUS(AE_OK);
272 	}
273 
274 	/* Allocate and initialize the evaluation information block */
275 
276 	info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
277 	if (!info) {
278 		return_ACPI_STATUS(AE_NO_MEMORY);
279 	}
280 
281 	info->prefix_node = region_obj2->extra.method_REG;
282 	info->pathname = NULL;
283 	info->parameters = args;
284 	info->flags = ACPI_IGNORE_RETURN_VALUE;
285 
286 	/*
287 	 * The _REG method has two arguments:
288 	 *
289 	 * Arg0 - Integer:
290 	 *  Operation region space ID Same value as region_obj->Region.space_id
291 	 *
292 	 * Arg1 - Integer:
293 	 *  connection status 1 for connecting the handler, 0 for disconnecting
294 	 *  the handler (Passed as a parameter)
295 	 */
296 	args[0] =
297 	    acpi_ut_create_integer_object((u64) region_obj->region.space_id);
298 	if (!args[0]) {
299 		status = AE_NO_MEMORY;
300 		goto cleanup1;
301 	}
302 
303 	args[1] = acpi_ut_create_integer_object((u64) function);
304 	if (!args[1]) {
305 		status = AE_NO_MEMORY;
306 		goto cleanup2;
307 	}
308 
309 	args[2] = NULL;		/* Terminate list */
310 
311 	/* Execute the method, no return value */
312 
313 	ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
314 			(ACPI_TYPE_METHOD, info->prefix_node, NULL));
315 
316 	status = acpi_ns_evaluate(info);
317 	acpi_ut_remove_reference(args[1]);
318 
319       cleanup2:
320 	acpi_ut_remove_reference(args[0]);
321 
322       cleanup1:
323 	ACPI_FREE(info);
324 	return_ACPI_STATUS(status);
325 }
326 
327 /*******************************************************************************
328  *
329  * FUNCTION:    acpi_ev_address_space_dispatch
330  *
331  * PARAMETERS:  region_obj          - Internal region object
332  *              field_obj           - Corresponding field. Can be NULL.
333  *              Function            - Read or Write operation
334  *              region_offset       - Where in the region to read or write
335  *              bit_width           - Field width in bits (8, 16, 32, or 64)
336  *              Value               - Pointer to in or out value, must be
337  *                                    a full 64-bit integer
338  *
339  * RETURN:      Status
340  *
341  * DESCRIPTION: Dispatch an address space or operation region access to
342  *              a previously installed handler.
343  *
344  ******************************************************************************/
345 
346 acpi_status
347 acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj,
348 			       union acpi_operand_object *field_obj,
349 			       u32 function,
350 			       u32 region_offset, u32 bit_width, u64 *value)
351 {
352 	acpi_status status;
353 	acpi_adr_space_handler handler;
354 	acpi_adr_space_setup region_setup;
355 	union acpi_operand_object *handler_desc;
356 	union acpi_operand_object *region_obj2;
357 	void *region_context = NULL;
358 	struct acpi_connection_info *context;
359 
360 	ACPI_FUNCTION_TRACE(ev_address_space_dispatch);
361 
362 	region_obj2 = acpi_ns_get_secondary_object(region_obj);
363 	if (!region_obj2) {
364 		return_ACPI_STATUS(AE_NOT_EXIST);
365 	}
366 
367 	/* Ensure that there is a handler associated with this region */
368 
369 	handler_desc = region_obj->region.handler;
370 	if (!handler_desc) {
371 		ACPI_ERROR((AE_INFO,
372 			    "No handler for Region [%4.4s] (%p) [%s]",
373 			    acpi_ut_get_node_name(region_obj->region.node),
374 			    region_obj,
375 			    acpi_ut_get_region_name(region_obj->region.
376 						    space_id)));
377 
378 		return_ACPI_STATUS(AE_NOT_EXIST);
379 	}
380 
381 	context = handler_desc->address_space.context;
382 
383 	/*
384 	 * It may be the case that the region has never been initialized.
385 	 * Some types of regions require special init code
386 	 */
387 	if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
388 
389 		/* This region has not been initialized yet, do it */
390 
391 		region_setup = handler_desc->address_space.setup;
392 		if (!region_setup) {
393 
394 			/* No initialization routine, exit with error */
395 
396 			ACPI_ERROR((AE_INFO,
397 				    "No init routine for region(%p) [%s]",
398 				    region_obj,
399 				    acpi_ut_get_region_name(region_obj->region.
400 							    space_id)));
401 			return_ACPI_STATUS(AE_NOT_EXIST);
402 		}
403 
404 		/*
405 		 * We must exit the interpreter because the region setup will
406 		 * potentially execute control methods (for example, the _REG method
407 		 * for this region)
408 		 */
409 		acpi_ex_exit_interpreter();
410 
411 		status = region_setup(region_obj, ACPI_REGION_ACTIVATE,
412 				      context, &region_context);
413 
414 		/* Re-enter the interpreter */
415 
416 		acpi_ex_enter_interpreter();
417 
418 		/* Check for failure of the Region Setup */
419 
420 		if (ACPI_FAILURE(status)) {
421 			ACPI_EXCEPTION((AE_INFO, status,
422 					"During region initialization: [%s]",
423 					acpi_ut_get_region_name(region_obj->
424 								region.
425 								space_id)));
426 			return_ACPI_STATUS(status);
427 		}
428 
429 		/* Region initialization may have been completed by region_setup */
430 
431 		if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
432 			region_obj->region.flags |= AOPOBJ_SETUP_COMPLETE;
433 
434 			if (region_obj2->extra.region_context) {
435 
436 				/* The handler for this region was already installed */
437 
438 				ACPI_FREE(region_context);
439 			} else {
440 				/*
441 				 * Save the returned context for use in all accesses to
442 				 * this particular region
443 				 */
444 				region_obj2->extra.region_context =
445 				    region_context;
446 			}
447 		}
448 	}
449 
450 	/* We have everything we need, we can invoke the address space handler */
451 
452 	handler = handler_desc->address_space.handler;
453 
454 	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
455 			  "Handler %p (@%p) Address %8.8X%8.8X [%s]\n",
456 			  &region_obj->region.handler->address_space, handler,
457 			  ACPI_FORMAT_NATIVE_UINT(region_obj->region.address +
458 						  region_offset),
459 			  acpi_ut_get_region_name(region_obj->region.
460 						  space_id)));
461 
462 	/*
463 	 * Special handling for generic_serial_bus and general_purpose_io:
464 	 * There are three extra parameters that must be passed to the
465 	 * handler via the context:
466 	 *   1) Connection buffer, a resource template from Connection() op.
467 	 *   2) Length of the above buffer.
468 	 *   3) Actual access length from the access_as() op.
469 	 */
470 	if (((region_obj->region.space_id == ACPI_ADR_SPACE_GSBUS) ||
471 	     (region_obj->region.space_id == ACPI_ADR_SPACE_GPIO)) &&
472 	    context && field_obj) {
473 
474 		/* Get the Connection (resource_template) buffer */
475 
476 		context->connection = field_obj->field.resource_buffer;
477 		context->length = field_obj->field.resource_length;
478 		context->access_length = field_obj->field.access_length;
479 	}
480 
481 	if (!(handler_desc->address_space.handler_flags &
482 	      ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
483 		/*
484 		 * For handlers other than the default (supplied) handlers, we must
485 		 * exit the interpreter because the handler *might* block -- we don't
486 		 * know what it will do, so we can't hold the lock on the intepreter.
487 		 */
488 		acpi_ex_exit_interpreter();
489 	}
490 
491 	/* Call the handler */
492 
493 	status = handler(function,
494 			 (region_obj->region.address + region_offset),
495 			 bit_width, value, context,
496 			 region_obj2->extra.region_context);
497 
498 	if (ACPI_FAILURE(status)) {
499 		ACPI_EXCEPTION((AE_INFO, status, "Returned by Handler for [%s]",
500 				acpi_ut_get_region_name(region_obj->region.
501 							space_id)));
502 	}
503 
504 	if (!(handler_desc->address_space.handler_flags &
505 	      ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
506 		/*
507 		 * We just returned from a non-default handler, we must re-enter the
508 		 * interpreter
509 		 */
510 		acpi_ex_enter_interpreter();
511 	}
512 
513 	return_ACPI_STATUS(status);
514 }
515 
516 /*******************************************************************************
517  *
518  * FUNCTION:    acpi_ev_detach_region
519  *
520  * PARAMETERS:  region_obj          - Region Object
521  *              acpi_ns_is_locked   - Namespace Region Already Locked?
522  *
523  * RETURN:      None
524  *
525  * DESCRIPTION: Break the association between the handler and the region
526  *              this is a two way association.
527  *
528  ******************************************************************************/
529 
530 void
531 acpi_ev_detach_region(union acpi_operand_object *region_obj,
532 		      u8 acpi_ns_is_locked)
533 {
534 	union acpi_operand_object *handler_obj;
535 	union acpi_operand_object *obj_desc;
536 	union acpi_operand_object **last_obj_ptr;
537 	acpi_adr_space_setup region_setup;
538 	void **region_context;
539 	union acpi_operand_object *region_obj2;
540 	acpi_status status;
541 
542 	ACPI_FUNCTION_TRACE(ev_detach_region);
543 
544 	region_obj2 = acpi_ns_get_secondary_object(region_obj);
545 	if (!region_obj2) {
546 		return_VOID;
547 	}
548 	region_context = &region_obj2->extra.region_context;
549 
550 	/* Get the address handler from the region object */
551 
552 	handler_obj = region_obj->region.handler;
553 	if (!handler_obj) {
554 
555 		/* This region has no handler, all done */
556 
557 		return_VOID;
558 	}
559 
560 	/* Find this region in the handler's list */
561 
562 	obj_desc = handler_obj->address_space.region_list;
563 	last_obj_ptr = &handler_obj->address_space.region_list;
564 
565 	while (obj_desc) {
566 
567 		/* Is this the correct Region? */
568 
569 		if (obj_desc == region_obj) {
570 			ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
571 					  "Removing Region %p from address handler %p\n",
572 					  region_obj, handler_obj));
573 
574 			/* This is it, remove it from the handler's list */
575 
576 			*last_obj_ptr = obj_desc->region.next;
577 			obj_desc->region.next = NULL;	/* Must clear field */
578 
579 			if (acpi_ns_is_locked) {
580 				status =
581 				    acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
582 				if (ACPI_FAILURE(status)) {
583 					return_VOID;
584 				}
585 			}
586 
587 			/* Now stop region accesses by executing the _REG method */
588 
589 			status =
590 			    acpi_ev_execute_reg_method(region_obj,
591 						       ACPI_REG_DISCONNECT);
592 			if (ACPI_FAILURE(status)) {
593 				ACPI_EXCEPTION((AE_INFO, status,
594 						"from region _REG, [%s]",
595 						acpi_ut_get_region_name
596 						(region_obj->region.space_id)));
597 			}
598 
599 			if (acpi_ns_is_locked) {
600 				status =
601 				    acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
602 				if (ACPI_FAILURE(status)) {
603 					return_VOID;
604 				}
605 			}
606 
607 			/*
608 			 * If the region has been activated, call the setup handler with
609 			 * the deactivate notification
610 			 */
611 			if (region_obj->region.flags & AOPOBJ_SETUP_COMPLETE) {
612 				region_setup = handler_obj->address_space.setup;
613 				status =
614 				    region_setup(region_obj,
615 						 ACPI_REGION_DEACTIVATE,
616 						 handler_obj->address_space.
617 						 context, region_context);
618 
619 				/* Init routine may fail, Just ignore errors */
620 
621 				if (ACPI_FAILURE(status)) {
622 					ACPI_EXCEPTION((AE_INFO, status,
623 							"from region handler - deactivate, [%s]",
624 							acpi_ut_get_region_name
625 							(region_obj->region.
626 							 space_id)));
627 				}
628 
629 				region_obj->region.flags &=
630 				    ~(AOPOBJ_SETUP_COMPLETE);
631 			}
632 
633 			/*
634 			 * Remove handler reference in the region
635 			 *
636 			 * NOTE: this doesn't mean that the region goes away, the region
637 			 * is just inaccessible as indicated to the _REG method
638 			 *
639 			 * If the region is on the handler's list, this must be the
640 			 * region's handler
641 			 */
642 			region_obj->region.handler = NULL;
643 			acpi_ut_remove_reference(handler_obj);
644 
645 			return_VOID;
646 		}
647 
648 		/* Walk the linked list of handlers */
649 
650 		last_obj_ptr = &obj_desc->region.next;
651 		obj_desc = obj_desc->region.next;
652 	}
653 
654 	/* If we get here, the region was not in the handler's region list */
655 
656 	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
657 			  "Cannot remove region %p from address handler %p\n",
658 			  region_obj, handler_obj));
659 
660 	return_VOID;
661 }
662 
663 /*******************************************************************************
664  *
665  * FUNCTION:    acpi_ev_attach_region
666  *
667  * PARAMETERS:  handler_obj         - Handler Object
668  *              region_obj          - Region Object
669  *              acpi_ns_is_locked   - Namespace Region Already Locked?
670  *
671  * RETURN:      None
672  *
673  * DESCRIPTION: Create the association between the handler and the region
674  *              this is a two way association.
675  *
676  ******************************************************************************/
677 
678 acpi_status
679 acpi_ev_attach_region(union acpi_operand_object *handler_obj,
680 		      union acpi_operand_object *region_obj,
681 		      u8 acpi_ns_is_locked)
682 {
683 
684 	ACPI_FUNCTION_TRACE(ev_attach_region);
685 
686 	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
687 			  "Adding Region [%4.4s] %p to address handler %p [%s]\n",
688 			  acpi_ut_get_node_name(region_obj->region.node),
689 			  region_obj, handler_obj,
690 			  acpi_ut_get_region_name(region_obj->region.
691 						  space_id)));
692 
693 	/* Link this region to the front of the handler's list */
694 
695 	region_obj->region.next = handler_obj->address_space.region_list;
696 	handler_obj->address_space.region_list = region_obj;
697 
698 	/* Install the region's handler */
699 
700 	if (region_obj->region.handler) {
701 		return_ACPI_STATUS(AE_ALREADY_EXISTS);
702 	}
703 
704 	region_obj->region.handler = handler_obj;
705 	acpi_ut_add_reference(handler_obj);
706 
707 	return_ACPI_STATUS(AE_OK);
708 }
709 
710 /*******************************************************************************
711  *
712  * FUNCTION:    acpi_ev_install_handler
713  *
714  * PARAMETERS:  walk_namespace callback
715  *
716  * DESCRIPTION: This routine installs an address handler into objects that are
717  *              of type Region or Device.
718  *
719  *              If the Object is a Device, and the device has a handler of
720  *              the same type then the search is terminated in that branch.
721  *
722  *              This is because the existing handler is closer in proximity
723  *              to any more regions than the one we are trying to install.
724  *
725  ******************************************************************************/
726 
727 static acpi_status
728 acpi_ev_install_handler(acpi_handle obj_handle,
729 			u32 level, void *context, void **return_value)
730 {
731 	union acpi_operand_object *handler_obj;
732 	union acpi_operand_object *next_handler_obj;
733 	union acpi_operand_object *obj_desc;
734 	struct acpi_namespace_node *node;
735 	acpi_status status;
736 
737 	ACPI_FUNCTION_NAME(ev_install_handler);
738 
739 	handler_obj = (union acpi_operand_object *)context;
740 
741 	/* Parameter validation */
742 
743 	if (!handler_obj) {
744 		return (AE_OK);
745 	}
746 
747 	/* Convert and validate the device handle */
748 
749 	node = acpi_ns_validate_handle(obj_handle);
750 	if (!node) {
751 		return (AE_BAD_PARAMETER);
752 	}
753 
754 	/*
755 	 * We only care about regions and objects that are allowed to have
756 	 * address space handlers
757 	 */
758 	if ((node->type != ACPI_TYPE_DEVICE) &&
759 	    (node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
760 		return (AE_OK);
761 	}
762 
763 	/* Check for an existing internal object */
764 
765 	obj_desc = acpi_ns_get_attached_object(node);
766 	if (!obj_desc) {
767 
768 		/* No object, just exit */
769 
770 		return (AE_OK);
771 	}
772 
773 	/* Devices are handled different than regions */
774 
775 	if (obj_desc->common.type == ACPI_TYPE_DEVICE) {
776 
777 		/* Check if this Device already has a handler for this address space */
778 
779 		next_handler_obj = obj_desc->device.handler;
780 		while (next_handler_obj) {
781 
782 			/* Found a handler, is it for the same address space? */
783 
784 			if (next_handler_obj->address_space.space_id ==
785 			    handler_obj->address_space.space_id) {
786 				ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
787 						  "Found handler for region [%s] in device %p(%p) "
788 						  "handler %p\n",
789 						  acpi_ut_get_region_name
790 						  (handler_obj->address_space.
791 						   space_id), obj_desc,
792 						  next_handler_obj,
793 						  handler_obj));
794 
795 				/*
796 				 * Since the object we found it on was a device, then it
797 				 * means that someone has already installed a handler for
798 				 * the branch of the namespace from this device on. Just
799 				 * bail out telling the walk routine to not traverse this
800 				 * branch. This preserves the scoping rule for handlers.
801 				 */
802 				return (AE_CTRL_DEPTH);
803 			}
804 
805 			/* Walk the linked list of handlers attached to this device */
806 
807 			next_handler_obj = next_handler_obj->address_space.next;
808 		}
809 
810 		/*
811 		 * As long as the device didn't have a handler for this space we
812 		 * don't care about it. We just ignore it and proceed.
813 		 */
814 		return (AE_OK);
815 	}
816 
817 	/* Object is a Region */
818 
819 	if (obj_desc->region.space_id != handler_obj->address_space.space_id) {
820 
821 		/* This region is for a different address space, just ignore it */
822 
823 		return (AE_OK);
824 	}
825 
826 	/*
827 	 * Now we have a region and it is for the handler's address space type.
828 	 *
829 	 * First disconnect region for any previous handler (if any)
830 	 */
831 	acpi_ev_detach_region(obj_desc, FALSE);
832 
833 	/* Connect the region to the new handler */
834 
835 	status = acpi_ev_attach_region(handler_obj, obj_desc, FALSE);
836 	return (status);
837 }
838 
839 /*******************************************************************************
840  *
841  * FUNCTION:    acpi_ev_install_space_handler
842  *
843  * PARAMETERS:  Node            - Namespace node for the device
844  *              space_id        - The address space ID
845  *              Handler         - Address of the handler
846  *              Setup           - Address of the setup function
847  *              Context         - Value passed to the handler on each access
848  *
849  * RETURN:      Status
850  *
851  * DESCRIPTION: Install a handler for all op_regions of a given space_id.
852  *              Assumes namespace is locked
853  *
854  ******************************************************************************/
855 
856 acpi_status
857 acpi_ev_install_space_handler(struct acpi_namespace_node * node,
858 			      acpi_adr_space_type space_id,
859 			      acpi_adr_space_handler handler,
860 			      acpi_adr_space_setup setup, void *context)
861 {
862 	union acpi_operand_object *obj_desc;
863 	union acpi_operand_object *handler_obj;
864 	acpi_status status;
865 	acpi_object_type type;
866 	u8 flags = 0;
867 
868 	ACPI_FUNCTION_TRACE(ev_install_space_handler);
869 
870 	/*
871 	 * This registration is valid for only the types below and the root. This
872 	 * is where the default handlers get placed.
873 	 */
874 	if ((node->type != ACPI_TYPE_DEVICE) &&
875 	    (node->type != ACPI_TYPE_PROCESSOR) &&
876 	    (node->type != ACPI_TYPE_THERMAL) && (node != acpi_gbl_root_node)) {
877 		status = AE_BAD_PARAMETER;
878 		goto unlock_and_exit;
879 	}
880 
881 	if (handler == ACPI_DEFAULT_HANDLER) {
882 		flags = ACPI_ADDR_HANDLER_DEFAULT_INSTALLED;
883 
884 		switch (space_id) {
885 		case ACPI_ADR_SPACE_SYSTEM_MEMORY:
886 			handler = acpi_ex_system_memory_space_handler;
887 			setup = acpi_ev_system_memory_region_setup;
888 			break;
889 
890 		case ACPI_ADR_SPACE_SYSTEM_IO:
891 			handler = acpi_ex_system_io_space_handler;
892 			setup = acpi_ev_io_space_region_setup;
893 			break;
894 
895 		case ACPI_ADR_SPACE_PCI_CONFIG:
896 			handler = acpi_ex_pci_config_space_handler;
897 			setup = acpi_ev_pci_config_region_setup;
898 			break;
899 
900 		case ACPI_ADR_SPACE_CMOS:
901 			handler = acpi_ex_cmos_space_handler;
902 			setup = acpi_ev_cmos_region_setup;
903 			break;
904 
905 		case ACPI_ADR_SPACE_PCI_BAR_TARGET:
906 			handler = acpi_ex_pci_bar_space_handler;
907 			setup = acpi_ev_pci_bar_region_setup;
908 			break;
909 
910 		case ACPI_ADR_SPACE_DATA_TABLE:
911 			handler = acpi_ex_data_table_space_handler;
912 			setup = NULL;
913 			break;
914 
915 		default:
916 			status = AE_BAD_PARAMETER;
917 			goto unlock_and_exit;
918 		}
919 	}
920 
921 	/* If the caller hasn't specified a setup routine, use the default */
922 
923 	if (!setup) {
924 		setup = acpi_ev_default_region_setup;
925 	}
926 
927 	/* Check for an existing internal object */
928 
929 	obj_desc = acpi_ns_get_attached_object(node);
930 	if (obj_desc) {
931 		/*
932 		 * The attached device object already exists. Make sure the handler
933 		 * is not already installed.
934 		 */
935 		handler_obj = obj_desc->device.handler;
936 
937 		/* Walk the handler list for this device */
938 
939 		while (handler_obj) {
940 
941 			/* Same space_id indicates a handler already installed */
942 
943 			if (handler_obj->address_space.space_id == space_id) {
944 				if (handler_obj->address_space.handler ==
945 				    handler) {
946 					/*
947 					 * It is (relatively) OK to attempt to install the SAME
948 					 * handler twice. This can easily happen with the
949 					 * PCI_Config space.
950 					 */
951 					status = AE_SAME_HANDLER;
952 					goto unlock_and_exit;
953 				} else {
954 					/* A handler is already installed */
955 
956 					status = AE_ALREADY_EXISTS;
957 				}
958 				goto unlock_and_exit;
959 			}
960 
961 			/* Walk the linked list of handlers */
962 
963 			handler_obj = handler_obj->address_space.next;
964 		}
965 	} else {
966 		ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
967 				  "Creating object on Device %p while installing handler\n",
968 				  node));
969 
970 		/* obj_desc does not exist, create one */
971 
972 		if (node->type == ACPI_TYPE_ANY) {
973 			type = ACPI_TYPE_DEVICE;
974 		} else {
975 			type = node->type;
976 		}
977 
978 		obj_desc = acpi_ut_create_internal_object(type);
979 		if (!obj_desc) {
980 			status = AE_NO_MEMORY;
981 			goto unlock_and_exit;
982 		}
983 
984 		/* Init new descriptor */
985 
986 		obj_desc->common.type = (u8) type;
987 
988 		/* Attach the new object to the Node */
989 
990 		status = acpi_ns_attach_object(node, obj_desc, type);
991 
992 		/* Remove local reference to the object */
993 
994 		acpi_ut_remove_reference(obj_desc);
995 
996 		if (ACPI_FAILURE(status)) {
997 			goto unlock_and_exit;
998 		}
999 	}
1000 
1001 	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
1002 			  "Installing address handler for region %s(%X) on Device %4.4s %p(%p)\n",
1003 			  acpi_ut_get_region_name(space_id), space_id,
1004 			  acpi_ut_get_node_name(node), node, obj_desc));
1005 
1006 	/*
1007 	 * Install the handler
1008 	 *
1009 	 * At this point there is no existing handler. Just allocate the object
1010 	 * for the handler and link it into the list.
1011 	 */
1012 	handler_obj =
1013 	    acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_ADDRESS_HANDLER);
1014 	if (!handler_obj) {
1015 		status = AE_NO_MEMORY;
1016 		goto unlock_and_exit;
1017 	}
1018 
1019 	/* Init handler obj */
1020 
1021 	handler_obj->address_space.space_id = (u8) space_id;
1022 	handler_obj->address_space.handler_flags = flags;
1023 	handler_obj->address_space.region_list = NULL;
1024 	handler_obj->address_space.node = node;
1025 	handler_obj->address_space.handler = handler;
1026 	handler_obj->address_space.context = context;
1027 	handler_obj->address_space.setup = setup;
1028 
1029 	/* Install at head of Device.address_space list */
1030 
1031 	handler_obj->address_space.next = obj_desc->device.handler;
1032 
1033 	/*
1034 	 * The Device object is the first reference on the handler_obj.
1035 	 * Each region that uses the handler adds a reference.
1036 	 */
1037 	obj_desc->device.handler = handler_obj;
1038 
1039 	/*
1040 	 * Walk the namespace finding all of the regions this
1041 	 * handler will manage.
1042 	 *
1043 	 * Start at the device and search the branch toward
1044 	 * the leaf nodes until either the leaf is encountered or
1045 	 * a device is detected that has an address handler of the
1046 	 * same type.
1047 	 *
1048 	 * In either case, back up and search down the remainder
1049 	 * of the branch
1050 	 */
1051 	status = acpi_ns_walk_namespace(ACPI_TYPE_ANY, node, ACPI_UINT32_MAX,
1052 					ACPI_NS_WALK_UNLOCK,
1053 					acpi_ev_install_handler, NULL,
1054 					handler_obj, NULL);
1055 
1056       unlock_and_exit:
1057 	return_ACPI_STATUS(status);
1058 }
1059 
1060 /*******************************************************************************
1061  *
1062  * FUNCTION:    acpi_ev_execute_reg_methods
1063  *
1064  * PARAMETERS:  Node            - Namespace node for the device
1065  *              space_id        - The address space ID
1066  *
1067  * RETURN:      Status
1068  *
1069  * DESCRIPTION: Run all _REG methods for the input Space ID;
1070  *              Note: assumes namespace is locked, or system init time.
1071  *
1072  ******************************************************************************/
1073 
1074 acpi_status
1075 acpi_ev_execute_reg_methods(struct acpi_namespace_node *node,
1076 			    acpi_adr_space_type space_id)
1077 {
1078 	acpi_status status;
1079 
1080 	ACPI_FUNCTION_TRACE(ev_execute_reg_methods);
1081 
1082 	/*
1083 	 * Run all _REG methods for all Operation Regions for this space ID. This
1084 	 * is a separate walk in order to handle any interdependencies between
1085 	 * regions and _REG methods. (i.e. handlers must be installed for all
1086 	 * regions of this Space ID before we can run any _REG methods)
1087 	 */
1088 	status = acpi_ns_walk_namespace(ACPI_TYPE_ANY, node, ACPI_UINT32_MAX,
1089 					ACPI_NS_WALK_UNLOCK, acpi_ev_reg_run,
1090 					NULL, &space_id, NULL);
1091 
1092 	/* Special case for EC: handle "orphan" _REG methods with no region */
1093 
1094 	if (space_id == ACPI_ADR_SPACE_EC) {
1095 		acpi_ev_orphan_ec_reg_method();
1096 	}
1097 
1098 	return_ACPI_STATUS(status);
1099 }
1100 
1101 /*******************************************************************************
1102  *
1103  * FUNCTION:    acpi_ev_reg_run
1104  *
1105  * PARAMETERS:  walk_namespace callback
1106  *
1107  * DESCRIPTION: Run _REG method for region objects of the requested space_iD
1108  *
1109  ******************************************************************************/
1110 
1111 static acpi_status
1112 acpi_ev_reg_run(acpi_handle obj_handle,
1113 		u32 level, void *context, void **return_value)
1114 {
1115 	union acpi_operand_object *obj_desc;
1116 	struct acpi_namespace_node *node;
1117 	acpi_adr_space_type space_id;
1118 	acpi_status status;
1119 
1120 	space_id = *ACPI_CAST_PTR(acpi_adr_space_type, context);
1121 
1122 	/* Convert and validate the device handle */
1123 
1124 	node = acpi_ns_validate_handle(obj_handle);
1125 	if (!node) {
1126 		return (AE_BAD_PARAMETER);
1127 	}
1128 
1129 	/*
1130 	 * We only care about regions.and objects that are allowed to have address
1131 	 * space handlers
1132 	 */
1133 	if ((node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
1134 		return (AE_OK);
1135 	}
1136 
1137 	/* Check for an existing internal object */
1138 
1139 	obj_desc = acpi_ns_get_attached_object(node);
1140 	if (!obj_desc) {
1141 
1142 		/* No object, just exit */
1143 
1144 		return (AE_OK);
1145 	}
1146 
1147 	/* Object is a Region */
1148 
1149 	if (obj_desc->region.space_id != space_id) {
1150 
1151 		/* This region is for a different address space, just ignore it */
1152 
1153 		return (AE_OK);
1154 	}
1155 
1156 	status = acpi_ev_execute_reg_method(obj_desc, ACPI_REG_CONNECT);
1157 	return (status);
1158 }
1159 
1160 /*******************************************************************************
1161  *
1162  * FUNCTION:    acpi_ev_orphan_ec_reg_method
1163  *
1164  * PARAMETERS:  None
1165  *
1166  * RETURN:      None
1167  *
1168  * DESCRIPTION: Execute an "orphan" _REG method that appears under the EC
1169  *              device. This is a _REG method that has no corresponding region
1170  *              within the EC device scope. The orphan _REG method appears to
1171  *              have been enabled by the description of the ECDT in the ACPI
1172  *              specification: "The availability of the region space can be
1173  *              detected by providing a _REG method object underneath the
1174  *              Embedded Controller device."
1175  *
1176  *              To quickly access the EC device, we use the EC_ID that appears
1177  *              within the ECDT. Otherwise, we would need to perform a time-
1178  *              consuming namespace walk, executing _HID methods to find the
1179  *              EC device.
1180  *
1181  ******************************************************************************/
1182 
1183 static void acpi_ev_orphan_ec_reg_method(void)
1184 {
1185 	struct acpi_table_ecdt *table;
1186 	acpi_status status;
1187 	struct acpi_object_list args;
1188 	union acpi_object objects[2];
1189 	struct acpi_namespace_node *ec_device_node;
1190 	struct acpi_namespace_node *reg_method;
1191 	struct acpi_namespace_node *next_node;
1192 
1193 	ACPI_FUNCTION_TRACE(ev_orphan_ec_reg_method);
1194 
1195 	/* Get the ECDT (if present in system) */
1196 
1197 	status = acpi_get_table(ACPI_SIG_ECDT, 0,
1198 				ACPI_CAST_INDIRECT_PTR(struct acpi_table_header,
1199 						       &table));
1200 	if (ACPI_FAILURE(status)) {
1201 		return_VOID;
1202 	}
1203 
1204 	/* We need a valid EC_ID string */
1205 
1206 	if (!(*table->id)) {
1207 		return_VOID;
1208 	}
1209 
1210 	/* Namespace is currently locked, must release */
1211 
1212 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
1213 
1214 	/* Get a handle to the EC device referenced in the ECDT */
1215 
1216 	status = acpi_get_handle(NULL,
1217 				 ACPI_CAST_PTR(char, table->id),
1218 				 ACPI_CAST_PTR(acpi_handle, &ec_device_node));
1219 	if (ACPI_FAILURE(status)) {
1220 		goto exit;
1221 	}
1222 
1223 	/* Get a handle to a _REG method immediately under the EC device */
1224 
1225 	status = acpi_get_handle(ec_device_node,
1226 				 METHOD_NAME__REG, ACPI_CAST_PTR(acpi_handle,
1227 								 &reg_method));
1228 	if (ACPI_FAILURE(status)) {
1229 		goto exit;
1230 	}
1231 
1232 	/*
1233 	 * Execute the _REG method only if there is no Operation Region in
1234 	 * this scope with the Embedded Controller space ID. Otherwise, it
1235 	 * will already have been executed. Note, this allows for Regions
1236 	 * with other space IDs to be present; but the code below will then
1237 	 * execute the _REG method with the EC space ID argument.
1238 	 */
1239 	next_node = acpi_ns_get_next_node(ec_device_node, NULL);
1240 	while (next_node) {
1241 		if ((next_node->type == ACPI_TYPE_REGION) &&
1242 		    (next_node->object) &&
1243 		    (next_node->object->region.space_id == ACPI_ADR_SPACE_EC)) {
1244 			goto exit;	/* Do not execute _REG */
1245 		}
1246 		next_node = acpi_ns_get_next_node(ec_device_node, next_node);
1247 	}
1248 
1249 	/* Evaluate the _REG(EC,Connect) method */
1250 
1251 	args.count = 2;
1252 	args.pointer = objects;
1253 	objects[0].type = ACPI_TYPE_INTEGER;
1254 	objects[0].integer.value = ACPI_ADR_SPACE_EC;
1255 	objects[1].type = ACPI_TYPE_INTEGER;
1256 	objects[1].integer.value = ACPI_REG_CONNECT;
1257 
1258 	status = acpi_evaluate_object(reg_method, NULL, &args, NULL);
1259 
1260       exit:
1261 	/* We ignore all errors from above, don't care */
1262 
1263 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
1264 	return_VOID;
1265 }
1266