xref: /openbmc/linux/drivers/acpi/acpica/evregion.c (revision 03fd525d)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: evregion - Operation Region support
5  *
6  * Copyright (C) 2000 - 2023, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acevents.h"
13 #include "acnamesp.h"
14 #include "acinterp.h"
15 
16 #define _COMPONENT          ACPI_EVENTS
17 ACPI_MODULE_NAME("evregion")
18 
19 extern u8 acpi_gbl_default_address_spaces[];
20 
21 /* Local prototypes */
22 
23 static void
24 acpi_ev_execute_orphan_reg_method(struct acpi_namespace_node *device_node,
25 				  acpi_adr_space_type space_id);
26 
27 static acpi_status
28 acpi_ev_reg_run(acpi_handle obj_handle,
29 		u32 level, void *context, void **return_value);
30 
31 /*******************************************************************************
32  *
33  * FUNCTION:    acpi_ev_initialize_op_regions
34  *
35  * PARAMETERS:  None
36  *
37  * RETURN:      Status
38  *
39  * DESCRIPTION: Execute _REG methods for all Operation Regions that have
40  *              an installed default region handler.
41  *
42  ******************************************************************************/
43 
acpi_ev_initialize_op_regions(void)44 acpi_status acpi_ev_initialize_op_regions(void)
45 {
46 	acpi_status status;
47 	u32 i;
48 
49 	ACPI_FUNCTION_TRACE(ev_initialize_op_regions);
50 
51 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
52 	if (ACPI_FAILURE(status)) {
53 		return_ACPI_STATUS(status);
54 	}
55 
56 	/* Run the _REG methods for op_regions in each default address space */
57 
58 	for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++) {
59 		/*
60 		 * Make sure the installed handler is the DEFAULT handler. If not the
61 		 * default, the _REG methods will have already been run (when the
62 		 * handler was installed)
63 		 */
64 		if (acpi_ev_has_default_handler(acpi_gbl_root_node,
65 						acpi_gbl_default_address_spaces
66 						[i])) {
67 			acpi_ev_execute_reg_methods(acpi_gbl_root_node,
68 						    ACPI_UINT32_MAX,
69 						    acpi_gbl_default_address_spaces
70 						    [i], ACPI_REG_CONNECT);
71 		}
72 	}
73 
74 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
75 	return_ACPI_STATUS(status);
76 }
77 
78 /*******************************************************************************
79  *
80  * FUNCTION:    acpi_ev_address_space_dispatch
81  *
82  * PARAMETERS:  region_obj          - Internal region object
83  *              field_obj           - Corresponding field. Can be NULL.
84  *              function            - Read or Write operation
85  *              region_offset       - Where in the region to read or write
86  *              bit_width           - Field width in bits (8, 16, 32, or 64)
87  *              value               - Pointer to in or out value, must be
88  *                                    a full 64-bit integer
89  *
90  * RETURN:      Status
91  *
92  * DESCRIPTION: Dispatch an address space or operation region access to
93  *              a previously installed handler.
94  *
95  * NOTE: During early initialization, we always install the default region
96  * handlers for Memory, I/O and PCI_Config. This ensures that these operation
97  * region address spaces are always available as per the ACPI specification.
98  * This is especially needed in order to support the execution of
99  * module-level AML code during loading of the ACPI tables.
100  *
101  ******************************************************************************/
102 
103 acpi_status
acpi_ev_address_space_dispatch(union acpi_operand_object * region_obj,union acpi_operand_object * field_obj,u32 function,u32 region_offset,u32 bit_width,u64 * value)104 acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj,
105 			       union acpi_operand_object *field_obj,
106 			       u32 function,
107 			       u32 region_offset, u32 bit_width, u64 *value)
108 {
109 	acpi_status status;
110 	acpi_adr_space_handler handler;
111 	acpi_adr_space_setup region_setup;
112 	union acpi_operand_object *handler_desc;
113 	union acpi_operand_object *region_obj2;
114 	void *region_context = NULL;
115 	struct acpi_connection_info *context;
116 	acpi_mutex context_mutex;
117 	u8 context_locked;
118 	acpi_physical_address address;
119 
120 	ACPI_FUNCTION_TRACE(ev_address_space_dispatch);
121 
122 	region_obj2 = acpi_ns_get_secondary_object(region_obj);
123 	if (!region_obj2) {
124 		return_ACPI_STATUS(AE_NOT_EXIST);
125 	}
126 
127 	/* Ensure that there is a handler associated with this region */
128 
129 	handler_desc = region_obj->region.handler;
130 	if (!handler_desc) {
131 		ACPI_ERROR((AE_INFO,
132 			    "No handler for Region [%4.4s] (%p) [%s]",
133 			    acpi_ut_get_node_name(region_obj->region.node),
134 			    region_obj,
135 			    acpi_ut_get_region_name(region_obj->region.
136 						    space_id)));
137 
138 		return_ACPI_STATUS(AE_NOT_EXIST);
139 	}
140 
141 	context = handler_desc->address_space.context;
142 	context_mutex = handler_desc->address_space.context_mutex;
143 	context_locked = FALSE;
144 
145 	/*
146 	 * It may be the case that the region has never been initialized.
147 	 * Some types of regions require special init code
148 	 */
149 	if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
150 
151 		/* This region has not been initialized yet, do it */
152 
153 		region_setup = handler_desc->address_space.setup;
154 		if (!region_setup) {
155 
156 			/* No initialization routine, exit with error */
157 
158 			ACPI_ERROR((AE_INFO,
159 				    "No init routine for region(%p) [%s]",
160 				    region_obj,
161 				    acpi_ut_get_region_name(region_obj->region.
162 							    space_id)));
163 			return_ACPI_STATUS(AE_NOT_EXIST);
164 		}
165 
166 		if (region_obj->region.space_id == ACPI_ADR_SPACE_PLATFORM_COMM) {
167 			struct acpi_pcc_info *ctx =
168 			    handler_desc->address_space.context;
169 
170 			ctx->internal_buffer =
171 			    field_obj->field.internal_pcc_buffer;
172 			ctx->length = (u16)region_obj->region.length;
173 			ctx->subspace_id = (u8)region_obj->region.address;
174 		}
175 
176 		if (region_obj->region.space_id ==
177 		    ACPI_ADR_SPACE_FIXED_HARDWARE) {
178 			struct acpi_ffh_info *ctx =
179 			    handler_desc->address_space.context;
180 
181 			ctx->length = region_obj->region.length;
182 			ctx->offset = region_obj->region.address;
183 		}
184 
185 		/*
186 		 * We must exit the interpreter because the region setup will
187 		 * potentially execute control methods (for example, the _REG method
188 		 * for this region)
189 		 */
190 		acpi_ex_exit_interpreter();
191 
192 		status = region_setup(region_obj, ACPI_REGION_ACTIVATE,
193 				      context, &region_context);
194 
195 		/* Re-enter the interpreter */
196 
197 		acpi_ex_enter_interpreter();
198 
199 		/* Check for failure of the Region Setup */
200 
201 		if (ACPI_FAILURE(status)) {
202 			ACPI_EXCEPTION((AE_INFO, status,
203 					"During region initialization: [%s]",
204 					acpi_ut_get_region_name(region_obj->
205 								region.
206 								space_id)));
207 			return_ACPI_STATUS(status);
208 		}
209 
210 		/* Region initialization may have been completed by region_setup */
211 
212 		if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
213 			region_obj->region.flags |= AOPOBJ_SETUP_COMPLETE;
214 
215 			/*
216 			 * Save the returned context for use in all accesses to
217 			 * the handler for this particular region
218 			 */
219 			if (!(region_obj2->extra.region_context)) {
220 				region_obj2->extra.region_context =
221 				    region_context;
222 			}
223 		}
224 	}
225 
226 	/* We have everything we need, we can invoke the address space handler */
227 
228 	handler = handler_desc->address_space.handler;
229 	address = (region_obj->region.address + region_offset);
230 
231 	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
232 			  "Handler %p (@%p) Address %8.8X%8.8X [%s]\n",
233 			  &region_obj->region.handler->address_space, handler,
234 			  ACPI_FORMAT_UINT64(address),
235 			  acpi_ut_get_region_name(region_obj->region.
236 						  space_id)));
237 
238 	if (!(handler_desc->address_space.handler_flags &
239 	      ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
240 		/*
241 		 * For handlers other than the default (supplied) handlers, we must
242 		 * exit the interpreter because the handler *might* block -- we don't
243 		 * know what it will do, so we can't hold the lock on the interpreter.
244 		 */
245 		acpi_ex_exit_interpreter();
246 	}
247 
248 	/*
249 	 * Special handling for generic_serial_bus and general_purpose_io:
250 	 * There are three extra parameters that must be passed to the
251 	 * handler via the context:
252 	 *   1) Connection buffer, a resource template from Connection() op
253 	 *   2) Length of the above buffer
254 	 *   3) Actual access length from the access_as() op
255 	 *
256 	 * Since we pass these extra parameters via the context, which is
257 	 * shared between threads, we must lock the context to avoid these
258 	 * parameters being changed from another thread before the handler
259 	 * has completed running.
260 	 *
261 	 * In addition, for general_purpose_io, the Address and bit_width fields
262 	 * are defined as follows:
263 	 *   1) Address is the pin number index of the field (bit offset from
264 	 *      the previous Connection)
265 	 *   2) bit_width is the actual bit length of the field (number of pins)
266 	 */
267 	if ((region_obj->region.space_id == ACPI_ADR_SPACE_GSBUS ||
268 	     region_obj->region.space_id == ACPI_ADR_SPACE_GPIO) &&
269 	    context && field_obj) {
270 
271 		status =
272 		    acpi_os_acquire_mutex(context_mutex, ACPI_WAIT_FOREVER);
273 		if (ACPI_FAILURE(status)) {
274 			goto re_enter_interpreter;
275 		}
276 
277 		context_locked = TRUE;
278 
279 		/* Get the Connection (resource_template) buffer */
280 
281 		context->connection = field_obj->field.resource_buffer;
282 		context->length = field_obj->field.resource_length;
283 		context->access_length = field_obj->field.access_length;
284 
285 		if (region_obj->region.space_id == ACPI_ADR_SPACE_GPIO) {
286 			address = field_obj->field.pin_number_index;
287 			bit_width = field_obj->field.bit_length;
288 		}
289 	}
290 
291 	/* Call the handler */
292 
293 	status = handler(function, address, bit_width, value, context,
294 			 region_obj2->extra.region_context);
295 
296 	if (context_locked) {
297 		acpi_os_release_mutex(context_mutex);
298 	}
299 
300 	if (ACPI_FAILURE(status)) {
301 		ACPI_EXCEPTION((AE_INFO, status, "Returned by Handler for [%s]",
302 				acpi_ut_get_region_name(region_obj->region.
303 							space_id)));
304 
305 		/*
306 		 * Special case for an EC timeout. These are seen so frequently
307 		 * that an additional error message is helpful
308 		 */
309 		if ((region_obj->region.space_id == ACPI_ADR_SPACE_EC) &&
310 		    (status == AE_TIME)) {
311 			ACPI_ERROR((AE_INFO,
312 				    "Timeout from EC hardware or EC device driver"));
313 		}
314 	}
315 
316 re_enter_interpreter:
317 	if (!(handler_desc->address_space.handler_flags &
318 	      ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
319 		/*
320 		 * We just returned from a non-default handler, we must re-enter the
321 		 * interpreter
322 		 */
323 		acpi_ex_enter_interpreter();
324 	}
325 
326 	return_ACPI_STATUS(status);
327 }
328 
329 /*******************************************************************************
330  *
331  * FUNCTION:    acpi_ev_detach_region
332  *
333  * PARAMETERS:  region_obj          - Region Object
334  *              acpi_ns_is_locked   - Namespace Region Already Locked?
335  *
336  * RETURN:      None
337  *
338  * DESCRIPTION: Break the association between the handler and the region
339  *              this is a two way association.
340  *
341  ******************************************************************************/
342 
343 void
acpi_ev_detach_region(union acpi_operand_object * region_obj,u8 acpi_ns_is_locked)344 acpi_ev_detach_region(union acpi_operand_object *region_obj,
345 		      u8 acpi_ns_is_locked)
346 {
347 	union acpi_operand_object *handler_obj;
348 	union acpi_operand_object *obj_desc;
349 	union acpi_operand_object *start_desc;
350 	union acpi_operand_object **last_obj_ptr;
351 	acpi_adr_space_setup region_setup;
352 	void **region_context;
353 	union acpi_operand_object *region_obj2;
354 	acpi_status status;
355 
356 	ACPI_FUNCTION_TRACE(ev_detach_region);
357 
358 	region_obj2 = acpi_ns_get_secondary_object(region_obj);
359 	if (!region_obj2) {
360 		return_VOID;
361 	}
362 	region_context = &region_obj2->extra.region_context;
363 
364 	/* Get the address handler from the region object */
365 
366 	handler_obj = region_obj->region.handler;
367 	if (!handler_obj) {
368 
369 		/* This region has no handler, all done */
370 
371 		return_VOID;
372 	}
373 
374 	/* Find this region in the handler's list */
375 
376 	obj_desc = handler_obj->address_space.region_list;
377 	start_desc = obj_desc;
378 	last_obj_ptr = &handler_obj->address_space.region_list;
379 
380 	while (obj_desc) {
381 
382 		/* Is this the correct Region? */
383 
384 		if (obj_desc == region_obj) {
385 			ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
386 					  "Removing Region %p from address handler %p\n",
387 					  region_obj, handler_obj));
388 
389 			/* This is it, remove it from the handler's list */
390 
391 			*last_obj_ptr = obj_desc->region.next;
392 			obj_desc->region.next = NULL;	/* Must clear field */
393 
394 			if (acpi_ns_is_locked) {
395 				status =
396 				    acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
397 				if (ACPI_FAILURE(status)) {
398 					return_VOID;
399 				}
400 			}
401 
402 			/* Now stop region accesses by executing the _REG method */
403 
404 			status =
405 			    acpi_ev_execute_reg_method(region_obj,
406 						       ACPI_REG_DISCONNECT);
407 			if (ACPI_FAILURE(status)) {
408 				ACPI_EXCEPTION((AE_INFO, status,
409 						"from region _REG, [%s]",
410 						acpi_ut_get_region_name
411 						(region_obj->region.space_id)));
412 			}
413 
414 			if (acpi_ns_is_locked) {
415 				status =
416 				    acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
417 				if (ACPI_FAILURE(status)) {
418 					return_VOID;
419 				}
420 			}
421 
422 			/*
423 			 * If the region has been activated, call the setup handler with
424 			 * the deactivate notification
425 			 */
426 			if (region_obj->region.flags & AOPOBJ_SETUP_COMPLETE) {
427 				region_setup = handler_obj->address_space.setup;
428 				status =
429 				    region_setup(region_obj,
430 						 ACPI_REGION_DEACTIVATE,
431 						 handler_obj->address_space.
432 						 context, region_context);
433 
434 				/*
435 				 * region_context should have been released by the deactivate
436 				 * operation. We don't need access to it anymore here.
437 				 */
438 				if (region_context) {
439 					*region_context = NULL;
440 				}
441 
442 				/* Init routine may fail, Just ignore errors */
443 
444 				if (ACPI_FAILURE(status)) {
445 					ACPI_EXCEPTION((AE_INFO, status,
446 							"from region handler - deactivate, [%s]",
447 							acpi_ut_get_region_name
448 							(region_obj->region.
449 							 space_id)));
450 				}
451 
452 				region_obj->region.flags &=
453 				    ~(AOPOBJ_SETUP_COMPLETE);
454 			}
455 
456 			/*
457 			 * Remove handler reference in the region
458 			 *
459 			 * NOTE: this doesn't mean that the region goes away, the region
460 			 * is just inaccessible as indicated to the _REG method
461 			 *
462 			 * If the region is on the handler's list, this must be the
463 			 * region's handler
464 			 */
465 			region_obj->region.handler = NULL;
466 			acpi_ut_remove_reference(handler_obj);
467 
468 			return_VOID;
469 		}
470 
471 		/* Walk the linked list of handlers */
472 
473 		last_obj_ptr = &obj_desc->region.next;
474 		obj_desc = obj_desc->region.next;
475 
476 		/* Prevent infinite loop if list is corrupted */
477 
478 		if (obj_desc == start_desc) {
479 			ACPI_ERROR((AE_INFO,
480 				    "Circular handler list in region object %p",
481 				    region_obj));
482 			return_VOID;
483 		}
484 	}
485 
486 	/* If we get here, the region was not in the handler's region list */
487 
488 	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
489 			  "Cannot remove region %p from address handler %p\n",
490 			  region_obj, handler_obj));
491 
492 	return_VOID;
493 }
494 
495 /*******************************************************************************
496  *
497  * FUNCTION:    acpi_ev_attach_region
498  *
499  * PARAMETERS:  handler_obj         - Handler Object
500  *              region_obj          - Region Object
501  *              acpi_ns_is_locked   - Namespace Region Already Locked?
502  *
503  * RETURN:      None
504  *
505  * DESCRIPTION: Create the association between the handler and the region
506  *              this is a two way association.
507  *
508  ******************************************************************************/
509 
510 acpi_status
acpi_ev_attach_region(union acpi_operand_object * handler_obj,union acpi_operand_object * region_obj,u8 acpi_ns_is_locked)511 acpi_ev_attach_region(union acpi_operand_object *handler_obj,
512 		      union acpi_operand_object *region_obj,
513 		      u8 acpi_ns_is_locked)
514 {
515 
516 	ACPI_FUNCTION_TRACE(ev_attach_region);
517 
518 	/* Install the region's handler */
519 
520 	if (region_obj->region.handler) {
521 		return_ACPI_STATUS(AE_ALREADY_EXISTS);
522 	}
523 
524 	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
525 			  "Adding Region [%4.4s] %p to address handler %p [%s]\n",
526 			  acpi_ut_get_node_name(region_obj->region.node),
527 			  region_obj, handler_obj,
528 			  acpi_ut_get_region_name(region_obj->region.
529 						  space_id)));
530 
531 	/* Link this region to the front of the handler's list */
532 
533 	region_obj->region.next = handler_obj->address_space.region_list;
534 	handler_obj->address_space.region_list = region_obj;
535 	region_obj->region.handler = handler_obj;
536 	acpi_ut_add_reference(handler_obj);
537 
538 	return_ACPI_STATUS(AE_OK);
539 }
540 
541 /*******************************************************************************
542  *
543  * FUNCTION:    acpi_ev_execute_reg_method
544  *
545  * PARAMETERS:  region_obj          - Region object
546  *              function            - Passed to _REG: On (1) or Off (0)
547  *
548  * RETURN:      Status
549  *
550  * DESCRIPTION: Execute _REG method for a region
551  *
552  ******************************************************************************/
553 
554 acpi_status
acpi_ev_execute_reg_method(union acpi_operand_object * region_obj,u32 function)555 acpi_ev_execute_reg_method(union acpi_operand_object *region_obj, u32 function)
556 {
557 	struct acpi_evaluate_info *info;
558 	union acpi_operand_object *args[3];
559 	union acpi_operand_object *region_obj2;
560 	const acpi_name *reg_name_ptr =
561 	    ACPI_CAST_PTR(acpi_name, METHOD_NAME__REG);
562 	struct acpi_namespace_node *method_node;
563 	struct acpi_namespace_node *node;
564 	acpi_status status;
565 
566 	ACPI_FUNCTION_TRACE(ev_execute_reg_method);
567 
568 	if (!acpi_gbl_namespace_initialized ||
569 	    region_obj->region.handler == NULL) {
570 		return_ACPI_STATUS(AE_OK);
571 	}
572 
573 	region_obj2 = acpi_ns_get_secondary_object(region_obj);
574 	if (!region_obj2) {
575 		return_ACPI_STATUS(AE_NOT_EXIST);
576 	}
577 
578 	/*
579 	 * Find any "_REG" method associated with this region definition.
580 	 * The method should always be updated as this function may be
581 	 * invoked after a namespace change.
582 	 */
583 	node = region_obj->region.node->parent;
584 	status =
585 	    acpi_ns_search_one_scope(*reg_name_ptr, node, ACPI_TYPE_METHOD,
586 				     &method_node);
587 	if (ACPI_SUCCESS(status)) {
588 		/*
589 		 * The _REG method is optional and there can be only one per
590 		 * region definition. This will be executed when the handler is
591 		 * attached or removed.
592 		 */
593 		region_obj2->extra.method_REG = method_node;
594 	}
595 	if (region_obj2->extra.method_REG == NULL) {
596 		return_ACPI_STATUS(AE_OK);
597 	}
598 
599 	/* _REG(DISCONNECT) should be paired with _REG(CONNECT) */
600 
601 	if ((function == ACPI_REG_CONNECT &&
602 	     region_obj->common.flags & AOPOBJ_REG_CONNECTED) ||
603 	    (function == ACPI_REG_DISCONNECT &&
604 	     !(region_obj->common.flags & AOPOBJ_REG_CONNECTED))) {
605 		return_ACPI_STATUS(AE_OK);
606 	}
607 
608 	/* Allocate and initialize the evaluation information block */
609 
610 	info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
611 	if (!info) {
612 		return_ACPI_STATUS(AE_NO_MEMORY);
613 	}
614 
615 	info->prefix_node = region_obj2->extra.method_REG;
616 	info->relative_pathname = NULL;
617 	info->parameters = args;
618 	info->flags = ACPI_IGNORE_RETURN_VALUE;
619 
620 	/*
621 	 * The _REG method has two arguments:
622 	 *
623 	 * arg0 - Integer:
624 	 *  Operation region space ID Same value as region_obj->Region.space_id
625 	 *
626 	 * arg1 - Integer:
627 	 *  connection status 1 for connecting the handler, 0 for disconnecting
628 	 *  the handler (Passed as a parameter)
629 	 */
630 	args[0] =
631 	    acpi_ut_create_integer_object((u64)region_obj->region.space_id);
632 	if (!args[0]) {
633 		status = AE_NO_MEMORY;
634 		goto cleanup1;
635 	}
636 
637 	args[1] = acpi_ut_create_integer_object((u64)function);
638 	if (!args[1]) {
639 		status = AE_NO_MEMORY;
640 		goto cleanup2;
641 	}
642 
643 	args[2] = NULL;		/* Terminate list */
644 
645 	/* Execute the method, no return value */
646 
647 	ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
648 			(ACPI_TYPE_METHOD, info->prefix_node, NULL));
649 
650 	status = acpi_ns_evaluate(info);
651 	acpi_ut_remove_reference(args[1]);
652 
653 	if (ACPI_FAILURE(status)) {
654 		goto cleanup2;
655 	}
656 
657 	if (function == ACPI_REG_CONNECT) {
658 		region_obj->common.flags |= AOPOBJ_REG_CONNECTED;
659 	} else {
660 		region_obj->common.flags &= ~AOPOBJ_REG_CONNECTED;
661 	}
662 
663 cleanup2:
664 	acpi_ut_remove_reference(args[0]);
665 
666 cleanup1:
667 	ACPI_FREE(info);
668 	return_ACPI_STATUS(status);
669 }
670 
671 /*******************************************************************************
672  *
673  * FUNCTION:    acpi_ev_execute_reg_methods
674  *
675  * PARAMETERS:  node            - Namespace node for the device
676  *              max_depth       - Depth to which search for _REG
677  *              space_id        - The address space ID
678  *              function        - Passed to _REG: On (1) or Off (0)
679  *
680  * RETURN:      None
681  *
682  * DESCRIPTION: Run all _REG methods for the input Space ID;
683  *              Note: assumes namespace is locked, or system init time.
684  *
685  ******************************************************************************/
686 
687 void
acpi_ev_execute_reg_methods(struct acpi_namespace_node * node,u32 max_depth,acpi_adr_space_type space_id,u32 function)688 acpi_ev_execute_reg_methods(struct acpi_namespace_node *node, u32 max_depth,
689 			    acpi_adr_space_type space_id, u32 function)
690 {
691 	struct acpi_reg_walk_info info;
692 
693 	ACPI_FUNCTION_TRACE(ev_execute_reg_methods);
694 
695 	/*
696 	 * These address spaces do not need a call to _REG, since the ACPI
697 	 * specification defines them as: "must always be accessible". Since
698 	 * they never change state (never become unavailable), no need to ever
699 	 * call _REG on them. Also, a data_table is not a "real" address space,
700 	 * so do not call _REG. September 2018.
701 	 */
702 	if ((space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) ||
703 	    (space_id == ACPI_ADR_SPACE_SYSTEM_IO) ||
704 	    (space_id == ACPI_ADR_SPACE_DATA_TABLE)) {
705 		return_VOID;
706 	}
707 
708 	info.space_id = space_id;
709 	info.function = function;
710 	info.reg_run_count = 0;
711 
712 	ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES,
713 			      "    Running _REG methods for SpaceId %s\n",
714 			      acpi_ut_get_region_name(info.space_id)));
715 
716 	/*
717 	 * Run all _REG methods for all Operation Regions for this space ID. This
718 	 * is a separate walk in order to handle any interdependencies between
719 	 * regions and _REG methods. (i.e. handlers must be installed for all
720 	 * regions of this Space ID before we can run any _REG methods)
721 	 */
722 	(void)acpi_ns_walk_namespace(ACPI_TYPE_ANY, node, max_depth,
723 				     ACPI_NS_WALK_UNLOCK, acpi_ev_reg_run, NULL,
724 				     &info, NULL);
725 
726 	/*
727 	 * Special case for EC and GPIO: handle "orphan" _REG methods with
728 	 * no region.
729 	 */
730 	if (space_id == ACPI_ADR_SPACE_EC || space_id == ACPI_ADR_SPACE_GPIO) {
731 		acpi_ev_execute_orphan_reg_method(node, space_id);
732 	}
733 
734 	ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES,
735 			      "    Executed %u _REG methods for SpaceId %s\n",
736 			      info.reg_run_count,
737 			      acpi_ut_get_region_name(info.space_id)));
738 
739 	return_VOID;
740 }
741 
742 /*******************************************************************************
743  *
744  * FUNCTION:    acpi_ev_reg_run
745  *
746  * PARAMETERS:  walk_namespace callback
747  *
748  * DESCRIPTION: Run _REG method for region objects of the requested spaceID
749  *
750  ******************************************************************************/
751 
752 static acpi_status
acpi_ev_reg_run(acpi_handle obj_handle,u32 level,void * context,void ** return_value)753 acpi_ev_reg_run(acpi_handle obj_handle,
754 		u32 level, void *context, void **return_value)
755 {
756 	union acpi_operand_object *obj_desc;
757 	struct acpi_namespace_node *node;
758 	acpi_status status;
759 	struct acpi_reg_walk_info *info;
760 
761 	info = ACPI_CAST_PTR(struct acpi_reg_walk_info, context);
762 
763 	/* Convert and validate the device handle */
764 
765 	node = acpi_ns_validate_handle(obj_handle);
766 	if (!node) {
767 		return (AE_BAD_PARAMETER);
768 	}
769 
770 	/*
771 	 * We only care about regions and objects that are allowed to have
772 	 * address space handlers
773 	 */
774 	if ((node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
775 		return (AE_OK);
776 	}
777 
778 	/* Check for an existing internal object */
779 
780 	obj_desc = acpi_ns_get_attached_object(node);
781 	if (!obj_desc) {
782 
783 		/* No object, just exit */
784 
785 		return (AE_OK);
786 	}
787 
788 	/* Object is a Region */
789 
790 	if (obj_desc->region.space_id != info->space_id) {
791 
792 		/* This region is for a different address space, just ignore it */
793 
794 		return (AE_OK);
795 	}
796 
797 	info->reg_run_count++;
798 	status = acpi_ev_execute_reg_method(obj_desc, info->function);
799 	return (status);
800 }
801 
802 /*******************************************************************************
803  *
804  * FUNCTION:    acpi_ev_execute_orphan_reg_method
805  *
806  * PARAMETERS:  device_node         - Namespace node for an ACPI device
807  *              space_id            - The address space ID
808  *
809  * RETURN:      None
810  *
811  * DESCRIPTION: Execute an "orphan" _REG method that appears under an ACPI
812  *              device. This is a _REG method that has no corresponding region
813  *              within the device's scope. ACPI tables depending on these
814  *              "orphan" _REG methods have been seen for both EC and GPIO
815  *              Operation Regions. Presumably the Windows ACPI implementation
816  *              always calls the _REG method independent of the presence of
817  *              an actual Operation Region with the correct address space ID.
818  *
819  *  MUTEX:      Assumes the namespace is locked
820  *
821  ******************************************************************************/
822 
823 static void
acpi_ev_execute_orphan_reg_method(struct acpi_namespace_node * device_node,acpi_adr_space_type space_id)824 acpi_ev_execute_orphan_reg_method(struct acpi_namespace_node *device_node,
825 				  acpi_adr_space_type space_id)
826 {
827 	acpi_handle reg_method;
828 	struct acpi_namespace_node *next_node;
829 	acpi_status status;
830 	struct acpi_object_list args;
831 	union acpi_object objects[2];
832 
833 	ACPI_FUNCTION_TRACE(ev_execute_orphan_reg_method);
834 
835 	if (!device_node) {
836 		return_VOID;
837 	}
838 
839 	/* Namespace is currently locked, must release */
840 
841 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
842 
843 	/* Get a handle to a _REG method immediately under the EC device */
844 
845 	status = acpi_get_handle(device_node, METHOD_NAME__REG, &reg_method);
846 	if (ACPI_FAILURE(status)) {
847 		goto exit;	/* There is no _REG method present */
848 	}
849 
850 	/*
851 	 * Execute the _REG method only if there is no Operation Region in
852 	 * this scope with the Embedded Controller space ID. Otherwise, it
853 	 * will already have been executed. Note, this allows for Regions
854 	 * with other space IDs to be present; but the code below will then
855 	 * execute the _REG method with the embedded_control space_ID argument.
856 	 */
857 	next_node = acpi_ns_get_next_node(device_node, NULL);
858 	while (next_node) {
859 		if ((next_node->type == ACPI_TYPE_REGION) &&
860 		    (next_node->object) &&
861 		    (next_node->object->region.space_id == space_id)) {
862 			goto exit;	/* Do not execute the _REG */
863 		}
864 
865 		next_node = acpi_ns_get_next_node(device_node, next_node);
866 	}
867 
868 	/* Evaluate the _REG(space_id,Connect) method */
869 
870 	args.count = 2;
871 	args.pointer = objects;
872 	objects[0].type = ACPI_TYPE_INTEGER;
873 	objects[0].integer.value = space_id;
874 	objects[1].type = ACPI_TYPE_INTEGER;
875 	objects[1].integer.value = ACPI_REG_CONNECT;
876 
877 	(void)acpi_evaluate_object(reg_method, NULL, &args, NULL);
878 
879 exit:
880 	/* We ignore all errors from above, don't care */
881 
882 	(void)acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
883 	return_VOID;
884 }
885