xref: /openbmc/linux/drivers/acpi/acpica/dsmthdat.c (revision e15a5365)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /*******************************************************************************
3  *
4  * Module Name: dsmthdat - control method arguments and local variables
5  *
6  ******************************************************************************/
7 
8 #include <acpi/acpi.h>
9 #include "accommon.h"
10 #include "acdispat.h"
11 #include "acnamesp.h"
12 #include "acinterp.h"
13 
14 #define _COMPONENT          ACPI_DISPATCHER
15 ACPI_MODULE_NAME("dsmthdat")
16 
17 /* Local prototypes */
18 static void
19 acpi_ds_method_data_delete_value(u8 type,
20 				 u32 index, struct acpi_walk_state *walk_state);
21 
22 static acpi_status
23 acpi_ds_method_data_set_value(u8 type,
24 			      u32 index,
25 			      union acpi_operand_object *object,
26 			      struct acpi_walk_state *walk_state);
27 
28 #ifdef ACPI_OBSOLETE_FUNCTIONS
29 acpi_object_type
30 acpi_ds_method_data_get_type(u16 opcode,
31 			     u32 index, struct acpi_walk_state *walk_state);
32 #endif
33 
34 /*******************************************************************************
35  *
36  * FUNCTION:    acpi_ds_method_data_init
37  *
38  * PARAMETERS:  walk_state          - Current walk state object
39  *
40  * RETURN:      Status
41  *
42  * DESCRIPTION: Initialize the data structures that hold the method's arguments
43  *              and locals. The data struct is an array of namespace nodes for
44  *              each - this allows ref_of and de_ref_of to work properly for these
45  *              special data types.
46  *
47  * NOTES:       walk_state fields are initialized to zero by the
48  *              ACPI_ALLOCATE_ZEROED().
49  *
50  *              A pseudo-Namespace Node is assigned to each argument and local
51  *              so that ref_of() can return a pointer to the Node.
52  *
53  ******************************************************************************/
54 
55 void acpi_ds_method_data_init(struct acpi_walk_state *walk_state)
56 {
57 	u32 i;
58 
59 	ACPI_FUNCTION_TRACE(ds_method_data_init);
60 
61 	/* Init the method arguments */
62 
63 	for (i = 0; i < ACPI_METHOD_NUM_ARGS; i++) {
64 		ACPI_MOVE_32_TO_32(&walk_state->arguments[i].name,
65 				   NAMEOF_ARG_NTE);
66 
67 		walk_state->arguments[i].name.integer |= (i << 24);
68 		walk_state->arguments[i].descriptor_type = ACPI_DESC_TYPE_NAMED;
69 		walk_state->arguments[i].type = ACPI_TYPE_ANY;
70 		walk_state->arguments[i].flags = ANOBJ_METHOD_ARG;
71 	}
72 
73 	/* Init the method locals */
74 
75 	for (i = 0; i < ACPI_METHOD_NUM_LOCALS; i++) {
76 		ACPI_MOVE_32_TO_32(&walk_state->local_variables[i].name,
77 				   NAMEOF_LOCAL_NTE);
78 
79 		walk_state->local_variables[i].name.integer |= (i << 24);
80 		walk_state->local_variables[i].descriptor_type =
81 		    ACPI_DESC_TYPE_NAMED;
82 		walk_state->local_variables[i].type = ACPI_TYPE_ANY;
83 		walk_state->local_variables[i].flags = ANOBJ_METHOD_LOCAL;
84 	}
85 
86 	return_VOID;
87 }
88 
89 /*******************************************************************************
90  *
91  * FUNCTION:    acpi_ds_method_data_delete_all
92  *
93  * PARAMETERS:  walk_state          - Current walk state object
94  *
95  * RETURN:      None
96  *
97  * DESCRIPTION: Delete method locals and arguments. Arguments are only
98  *              deleted if this method was called from another method.
99  *
100  ******************************************************************************/
101 
102 void acpi_ds_method_data_delete_all(struct acpi_walk_state *walk_state)
103 {
104 	u32 index;
105 
106 	ACPI_FUNCTION_TRACE(ds_method_data_delete_all);
107 
108 	/* Detach the locals */
109 
110 	for (index = 0; index < ACPI_METHOD_NUM_LOCALS; index++) {
111 		if (walk_state->local_variables[index].object) {
112 			ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Deleting Local%u=%p\n",
113 					  index,
114 					  walk_state->local_variables[index].
115 					  object));
116 
117 			/* Detach object (if present) and remove a reference */
118 
119 			acpi_ns_detach_object(&walk_state->
120 					      local_variables[index]);
121 		}
122 	}
123 
124 	/* Detach the arguments */
125 
126 	for (index = 0; index < ACPI_METHOD_NUM_ARGS; index++) {
127 		if (walk_state->arguments[index].object) {
128 			ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Deleting Arg%u=%p\n",
129 					  index,
130 					  walk_state->arguments[index].object));
131 
132 			/* Detach object (if present) and remove a reference */
133 
134 			acpi_ns_detach_object(&walk_state->arguments[index]);
135 		}
136 	}
137 
138 	return_VOID;
139 }
140 
141 /*******************************************************************************
142  *
143  * FUNCTION:    acpi_ds_method_data_init_args
144  *
145  * PARAMETERS:  *params         - Pointer to a parameter list for the method
146  *              max_param_count - The arg count for this method
147  *              walk_state      - Current walk state object
148  *
149  * RETURN:      Status
150  *
151  * DESCRIPTION: Initialize arguments for a method. The parameter list is a list
152  *              of ACPI operand objects, either null terminated or whose length
153  *              is defined by max_param_count.
154  *
155  ******************************************************************************/
156 
157 acpi_status
158 acpi_ds_method_data_init_args(union acpi_operand_object **params,
159 			      u32 max_param_count,
160 			      struct acpi_walk_state *walk_state)
161 {
162 	acpi_status status;
163 	u32 index = 0;
164 
165 	ACPI_FUNCTION_TRACE_PTR(ds_method_data_init_args, params);
166 
167 	if (!params) {
168 		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
169 				  "No parameter list passed to method\n"));
170 		return_ACPI_STATUS(AE_OK);
171 	}
172 
173 	/* Copy passed parameters into the new method stack frame */
174 
175 	while ((index < ACPI_METHOD_NUM_ARGS) &&
176 	       (index < max_param_count) && params[index]) {
177 		/*
178 		 * A valid parameter.
179 		 * Store the argument in the method/walk descriptor.
180 		 * Do not copy the arg in order to implement call by reference
181 		 */
182 		status =
183 		    acpi_ds_method_data_set_value(ACPI_REFCLASS_ARG, index,
184 						  params[index], walk_state);
185 		if (ACPI_FAILURE(status)) {
186 			return_ACPI_STATUS(status);
187 		}
188 
189 		index++;
190 	}
191 
192 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "%u args passed to method\n", index));
193 	return_ACPI_STATUS(AE_OK);
194 }
195 
196 /*******************************************************************************
197  *
198  * FUNCTION:    acpi_ds_method_data_get_node
199  *
200  * PARAMETERS:  type                - Either ACPI_REFCLASS_LOCAL or
201  *                                    ACPI_REFCLASS_ARG
202  *              index               - Which Local or Arg whose type to get
203  *              walk_state          - Current walk state object
204  *              node                - Where the node is returned.
205  *
206  * RETURN:      Status and node
207  *
208  * DESCRIPTION: Get the Node associated with a local or arg.
209  *
210  ******************************************************************************/
211 
212 acpi_status
213 acpi_ds_method_data_get_node(u8 type,
214 			     u32 index,
215 			     struct acpi_walk_state *walk_state,
216 			     struct acpi_namespace_node **node)
217 {
218 	ACPI_FUNCTION_TRACE(ds_method_data_get_node);
219 
220 	/*
221 	 * Method Locals and Arguments are supported
222 	 */
223 	switch (type) {
224 	case ACPI_REFCLASS_LOCAL:
225 
226 		if (index > ACPI_METHOD_MAX_LOCAL) {
227 			ACPI_ERROR((AE_INFO,
228 				    "Local index %u is invalid (max %u)",
229 				    index, ACPI_METHOD_MAX_LOCAL));
230 			return_ACPI_STATUS(AE_AML_INVALID_INDEX);
231 		}
232 
233 		/* Return a pointer to the pseudo-node */
234 
235 		*node = &walk_state->local_variables[index];
236 		break;
237 
238 	case ACPI_REFCLASS_ARG:
239 
240 		if (index > ACPI_METHOD_MAX_ARG) {
241 			ACPI_ERROR((AE_INFO,
242 				    "Arg index %u is invalid (max %u)",
243 				    index, ACPI_METHOD_MAX_ARG));
244 			return_ACPI_STATUS(AE_AML_INVALID_INDEX);
245 		}
246 
247 		/* Return a pointer to the pseudo-node */
248 
249 		*node = &walk_state->arguments[index];
250 		break;
251 
252 	default:
253 
254 		ACPI_ERROR((AE_INFO, "Type %u is invalid", type));
255 		return_ACPI_STATUS(AE_TYPE);
256 	}
257 
258 	return_ACPI_STATUS(AE_OK);
259 }
260 
261 /*******************************************************************************
262  *
263  * FUNCTION:    acpi_ds_method_data_set_value
264  *
265  * PARAMETERS:  type                - Either ACPI_REFCLASS_LOCAL or
266  *                                    ACPI_REFCLASS_ARG
267  *              index               - Which Local or Arg to get
268  *              object              - Object to be inserted into the stack entry
269  *              walk_state          - Current walk state object
270  *
271  * RETURN:      Status
272  *
273  * DESCRIPTION: Insert an object onto the method stack at entry Opcode:Index.
274  *              Note: There is no "implicit conversion" for locals.
275  *
276  ******************************************************************************/
277 
278 static acpi_status
279 acpi_ds_method_data_set_value(u8 type,
280 			      u32 index,
281 			      union acpi_operand_object *object,
282 			      struct acpi_walk_state *walk_state)
283 {
284 	acpi_status status;
285 	struct acpi_namespace_node *node;
286 
287 	ACPI_FUNCTION_TRACE(ds_method_data_set_value);
288 
289 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
290 			  "NewObj %p Type %2.2X, Refs=%u [%s]\n", object,
291 			  type, object->common.reference_count,
292 			  acpi_ut_get_type_name(object->common.type)));
293 
294 	/* Get the namespace node for the arg/local */
295 
296 	status = acpi_ds_method_data_get_node(type, index, walk_state, &node);
297 	if (ACPI_FAILURE(status)) {
298 		return_ACPI_STATUS(status);
299 	}
300 
301 	/*
302 	 * Increment ref count so object can't be deleted while installed.
303 	 * NOTE: We do not copy the object in order to preserve the call by
304 	 * reference semantics of ACPI Control Method invocation.
305 	 * (See ACPI Specification 2.0C)
306 	 */
307 	acpi_ut_add_reference(object);
308 
309 	/* Install the object */
310 
311 	node->object = object;
312 	return_ACPI_STATUS(status);
313 }
314 
315 /*******************************************************************************
316  *
317  * FUNCTION:    acpi_ds_method_data_get_value
318  *
319  * PARAMETERS:  type                - Either ACPI_REFCLASS_LOCAL or
320  *                                    ACPI_REFCLASS_ARG
321  *              index               - Which localVar or argument to get
322  *              walk_state          - Current walk state object
323  *              dest_desc           - Where Arg or Local value is returned
324  *
325  * RETURN:      Status
326  *
327  * DESCRIPTION: Retrieve value of selected Arg or Local for this method
328  *              Used only in acpi_ex_resolve_to_value().
329  *
330  ******************************************************************************/
331 
332 acpi_status
333 acpi_ds_method_data_get_value(u8 type,
334 			      u32 index,
335 			      struct acpi_walk_state *walk_state,
336 			      union acpi_operand_object **dest_desc)
337 {
338 	acpi_status status;
339 	struct acpi_namespace_node *node;
340 	union acpi_operand_object *object;
341 
342 	ACPI_FUNCTION_TRACE(ds_method_data_get_value);
343 
344 	/* Validate the object descriptor */
345 
346 	if (!dest_desc) {
347 		ACPI_ERROR((AE_INFO, "Null object descriptor pointer"));
348 		return_ACPI_STATUS(AE_BAD_PARAMETER);
349 	}
350 
351 	/* Get the namespace node for the arg/local */
352 
353 	status = acpi_ds_method_data_get_node(type, index, walk_state, &node);
354 	if (ACPI_FAILURE(status)) {
355 		return_ACPI_STATUS(status);
356 	}
357 
358 	/* Get the object from the node */
359 
360 	object = node->object;
361 
362 	/* Examine the returned object, it must be valid. */
363 
364 	if (!object) {
365 		/*
366 		 * Index points to uninitialized object.
367 		 * This means that either 1) The expected argument was
368 		 * not passed to the method, or 2) A local variable
369 		 * was referenced by the method (via the ASL)
370 		 * before it was initialized. Either case is an error.
371 		 */
372 
373 		/* If slack enabled, init the local_x/arg_x to an Integer of value zero */
374 
375 		if (acpi_gbl_enable_interpreter_slack) {
376 			object = acpi_ut_create_integer_object((u64) 0);
377 			if (!object) {
378 				return_ACPI_STATUS(AE_NO_MEMORY);
379 			}
380 
381 			node->object = object;
382 		}
383 
384 		/* Otherwise, return the error */
385 
386 		else
387 			switch (type) {
388 			case ACPI_REFCLASS_ARG:
389 
390 				ACPI_ERROR((AE_INFO,
391 					    "Uninitialized Arg[%u] at node %p",
392 					    index, node));
393 
394 				return_ACPI_STATUS(AE_AML_UNINITIALIZED_ARG);
395 
396 			case ACPI_REFCLASS_LOCAL:
397 				/*
398 				 * No error message for this case, will be trapped again later to
399 				 * detect and ignore cases of Store(local_x,local_x)
400 				 */
401 				return_ACPI_STATUS(AE_AML_UNINITIALIZED_LOCAL);
402 
403 			default:
404 
405 				ACPI_ERROR((AE_INFO,
406 					    "Not a Arg/Local opcode: 0x%X",
407 					    type));
408 				return_ACPI_STATUS(AE_AML_INTERNAL);
409 			}
410 	}
411 
412 	/*
413 	 * The Index points to an initialized and valid object.
414 	 * Return an additional reference to the object
415 	 */
416 	*dest_desc = object;
417 	acpi_ut_add_reference(object);
418 
419 	return_ACPI_STATUS(AE_OK);
420 }
421 
422 /*******************************************************************************
423  *
424  * FUNCTION:    acpi_ds_method_data_delete_value
425  *
426  * PARAMETERS:  type                - Either ACPI_REFCLASS_LOCAL or
427  *                                    ACPI_REFCLASS_ARG
428  *              index               - Which localVar or argument to delete
429  *              walk_state          - Current walk state object
430  *
431  * RETURN:      None
432  *
433  * DESCRIPTION: Delete the entry at Opcode:Index. Inserts
434  *              a null into the stack slot after the object is deleted.
435  *
436  ******************************************************************************/
437 
438 static void
439 acpi_ds_method_data_delete_value(u8 type,
440 				 u32 index, struct acpi_walk_state *walk_state)
441 {
442 	acpi_status status;
443 	struct acpi_namespace_node *node;
444 	union acpi_operand_object *object;
445 
446 	ACPI_FUNCTION_TRACE(ds_method_data_delete_value);
447 
448 	/* Get the namespace node for the arg/local */
449 
450 	status = acpi_ds_method_data_get_node(type, index, walk_state, &node);
451 	if (ACPI_FAILURE(status)) {
452 		return_VOID;
453 	}
454 
455 	/* Get the associated object */
456 
457 	object = acpi_ns_get_attached_object(node);
458 
459 	/*
460 	 * Undefine the Arg or Local by setting its descriptor
461 	 * pointer to NULL. Locals/Args can contain both
462 	 * ACPI_OPERAND_OBJECTS and ACPI_NAMESPACE_NODEs
463 	 */
464 	node->object = NULL;
465 
466 	if ((object) &&
467 	    (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_OPERAND)) {
468 		/*
469 		 * There is a valid object.
470 		 * Decrement the reference count by one to balance the
471 		 * increment when the object was stored.
472 		 */
473 		acpi_ut_remove_reference(object);
474 	}
475 
476 	return_VOID;
477 }
478 
479 /*******************************************************************************
480  *
481  * FUNCTION:    acpi_ds_store_object_to_local
482  *
483  * PARAMETERS:  type                - Either ACPI_REFCLASS_LOCAL or
484  *                                    ACPI_REFCLASS_ARG
485  *              index               - Which Local or Arg to set
486  *              obj_desc            - Value to be stored
487  *              walk_state          - Current walk state
488  *
489  * RETURN:      Status
490  *
491  * DESCRIPTION: Store a value in an Arg or Local. The obj_desc is installed
492  *              as the new value for the Arg or Local and the reference count
493  *              for obj_desc is incremented.
494  *
495  ******************************************************************************/
496 
497 acpi_status
498 acpi_ds_store_object_to_local(u8 type,
499 			      u32 index,
500 			      union acpi_operand_object *obj_desc,
501 			      struct acpi_walk_state *walk_state)
502 {
503 	acpi_status status;
504 	struct acpi_namespace_node *node;
505 	union acpi_operand_object *current_obj_desc;
506 	union acpi_operand_object *new_obj_desc;
507 
508 	ACPI_FUNCTION_TRACE(ds_store_object_to_local);
509 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Type=%2.2X Index=%u Obj=%p\n",
510 			  type, index, obj_desc));
511 
512 	/* Parameter validation */
513 
514 	if (!obj_desc) {
515 		return_ACPI_STATUS(AE_BAD_PARAMETER);
516 	}
517 
518 	/* Get the namespace node for the arg/local */
519 
520 	status = acpi_ds_method_data_get_node(type, index, walk_state, &node);
521 	if (ACPI_FAILURE(status)) {
522 		return_ACPI_STATUS(status);
523 	}
524 
525 	current_obj_desc = acpi_ns_get_attached_object(node);
526 	if (current_obj_desc == obj_desc) {
527 		ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p already installed!\n",
528 				  obj_desc));
529 		return_ACPI_STATUS(status);
530 	}
531 
532 	/*
533 	 * If the reference count on the object is more than one, we must
534 	 * take a copy of the object before we store. A reference count
535 	 * of exactly 1 means that the object was just created during the
536 	 * evaluation of an expression, and we can safely use it since it
537 	 * is not used anywhere else.
538 	 */
539 	new_obj_desc = obj_desc;
540 	if (obj_desc->common.reference_count > 1) {
541 		status =
542 		    acpi_ut_copy_iobject_to_iobject(obj_desc, &new_obj_desc,
543 						    walk_state);
544 		if (ACPI_FAILURE(status)) {
545 			return_ACPI_STATUS(status);
546 		}
547 	}
548 
549 	/*
550 	 * If there is an object already in this slot, we either
551 	 * have to delete it, or if this is an argument and there
552 	 * is an object reference stored there, we have to do
553 	 * an indirect store!
554 	 */
555 	if (current_obj_desc) {
556 		/*
557 		 * Check for an indirect store if an argument
558 		 * contains an object reference (stored as an Node).
559 		 * We don't allow this automatic dereferencing for
560 		 * locals, since a store to a local should overwrite
561 		 * anything there, including an object reference.
562 		 *
563 		 * If both Arg0 and Local0 contain ref_of (Local4):
564 		 *
565 		 * Store (1, Arg0)             - Causes indirect store to local4
566 		 * Store (1, Local0)           - Stores 1 in local0, overwriting
567 		 *                                  the reference to local4
568 		 * Store (1, de_refof (Local0)) - Causes indirect store to local4
569 		 *
570 		 * Weird, but true.
571 		 */
572 		if (type == ACPI_REFCLASS_ARG) {
573 			/*
574 			 * If we have a valid reference object that came from ref_of(),
575 			 * do the indirect store
576 			 */
577 			if ((ACPI_GET_DESCRIPTOR_TYPE(current_obj_desc) ==
578 			     ACPI_DESC_TYPE_OPERAND) &&
579 			    (current_obj_desc->common.type ==
580 			     ACPI_TYPE_LOCAL_REFERENCE) &&
581 			    (current_obj_desc->reference.class ==
582 			     ACPI_REFCLASS_REFOF)) {
583 				ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
584 						  "Arg (%p) is an ObjRef(Node), storing in node %p\n",
585 						  new_obj_desc,
586 						  current_obj_desc));
587 
588 				/*
589 				 * Store this object to the Node (perform the indirect store)
590 				 * NOTE: No implicit conversion is performed, as per the ACPI
591 				 * specification rules on storing to Locals/Args.
592 				 */
593 				status =
594 				    acpi_ex_store_object_to_node(new_obj_desc,
595 								 current_obj_desc->
596 								 reference.
597 								 object,
598 								 walk_state,
599 								 ACPI_NO_IMPLICIT_CONVERSION);
600 
601 				/* Remove local reference if we copied the object above */
602 
603 				if (new_obj_desc != obj_desc) {
604 					acpi_ut_remove_reference(new_obj_desc);
605 				}
606 
607 				return_ACPI_STATUS(status);
608 			}
609 		}
610 
611 		/* Delete the existing object before storing the new one */
612 
613 		acpi_ds_method_data_delete_value(type, index, walk_state);
614 	}
615 
616 	/*
617 	 * Install the Obj descriptor (*new_obj_desc) into
618 	 * the descriptor for the Arg or Local.
619 	 * (increments the object reference count by one)
620 	 */
621 	status =
622 	    acpi_ds_method_data_set_value(type, index, new_obj_desc,
623 					  walk_state);
624 
625 	/* Remove local reference if we copied the object above */
626 
627 	if (new_obj_desc != obj_desc) {
628 		acpi_ut_remove_reference(new_obj_desc);
629 	}
630 
631 	return_ACPI_STATUS(status);
632 }
633 
634 #ifdef ACPI_OBSOLETE_FUNCTIONS
635 /*******************************************************************************
636  *
637  * FUNCTION:    acpi_ds_method_data_get_type
638  *
639  * PARAMETERS:  opcode              - Either AML_FIRST LOCAL_OP or
640  *                                    AML_FIRST_ARG_OP
641  *              index               - Which Local or Arg whose type to get
642  *              walk_state          - Current walk state object
643  *
644  * RETURN:      Data type of current value of the selected Arg or Local
645  *
646  * DESCRIPTION: Get the type of the object stored in the Local or Arg
647  *
648  ******************************************************************************/
649 
650 acpi_object_type
651 acpi_ds_method_data_get_type(u16 opcode,
652 			     u32 index, struct acpi_walk_state *walk_state)
653 {
654 	acpi_status status;
655 	struct acpi_namespace_node *node;
656 	union acpi_operand_object *object;
657 
658 	ACPI_FUNCTION_TRACE(ds_method_data_get_type);
659 
660 	/* Get the namespace node for the arg/local */
661 
662 	status = acpi_ds_method_data_get_node(opcode, index, walk_state, &node);
663 	if (ACPI_FAILURE(status)) {
664 		return_VALUE((ACPI_TYPE_NOT_FOUND));
665 	}
666 
667 	/* Get the object */
668 
669 	object = acpi_ns_get_attached_object(node);
670 	if (!object) {
671 
672 		/* Uninitialized local/arg, return TYPE_ANY */
673 
674 		return_VALUE(ACPI_TYPE_ANY);
675 	}
676 
677 	/* Get the object type */
678 
679 	return_VALUE(object->type);
680 }
681 #endif
682