1 /******************************************************************************
2 *
3 * Module Name: dscontrol - Support for execution control opcodes -
4 * if/else/while/return
5 *
6 *****************************************************************************/
7
8 /*
9 * Copyright (C) 2000 - 2011, Intel Corp.
10 * All rights reserved.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions, and the following disclaimer,
17 * without modification.
18 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19 * substantially similar to the "NO WARRANTY" disclaimer below
20 * ("Disclaimer") and any redistribution must be conditioned upon
21 * including a substantially similar Disclaimer requirement for further
22 * binary redistribution.
23 * 3. Neither the names of the above-listed copyright holders nor the names
24 * of any contributors may be used to endorse or promote products derived
25 * from this software without specific prior written permission.
26 *
27 * Alternatively, this software may be distributed under the terms of the
28 * GNU General Public License ("GPL") version 2 as published by the Free
29 * Software Foundation.
69 ******************************************************************************/
70
71 ACPI_STATUS
72 AcpiDsExecBeginControlOp (
73 ACPI_WALK_STATE *WalkState,
74 ACPI_PARSE_OBJECT *Op)
75 {
76 ACPI_STATUS Status = AE_OK;
77 ACPI_GENERIC_STATE *ControlState;
78
79
80 ACPI_FUNCTION_NAME (DsExecBeginControlOp);
81
82
83 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Op=%p Opcode=%2.2X State=%p\n",
84 Op, Op->Common.AmlOpcode, WalkState));
85
86 switch (Op->Common.AmlOpcode)
87 {
88 case AML_WHILE_OP:
89
90 /*
91 * If this is an additional iteration of a while loop, continue.
92 * There is no need to allocate a new control state.
93 */
94 if (WalkState->ControlState)
95 {
96 if (WalkState->ControlState->Control.AmlPredicateStart ==
97 (WalkState->ParserState.Aml - 1))
98 {
99 /* Reset the state to start-of-loop */
100
101 WalkState->ControlState->Common.State =
102 ACPI_CONTROL_CONDITIONAL_EXECUTING;
103 break;
104 }
105 }
106
107 /*lint -fallthrough */
108
109 case AML_IF_OP:
110
111 /*
112 * IF/WHILE: Create a new control state to manage these
113 * constructs. We need to manage these as a stack, in order
114 * to handle nesting.
115 */
116 ControlState = AcpiUtCreateControlState ();
117 if (!ControlState)
118 {
119 Status = AE_NO_MEMORY;
120 break;
121 }
122 /*
123 * Save a pointer to the predicate for multiple executions
124 * of a loop
125 */
126 ControlState->Control.AmlPredicateStart = WalkState->ParserState.Aml - 1;
127 ControlState->Control.PackageEnd = WalkState->ParserState.PkgEnd;
128 ControlState->Control.Opcode = Op->Common.AmlOpcode;
129
130
133 AcpiUtPushGenericState (&WalkState->ControlState, ControlState);
134 break;
135
136 case AML_ELSE_OP:
137
138 /* Predicate is in the state object */
139 /* If predicate is true, the IF was executed, ignore ELSE part */
140
141 if (WalkState->LastPredicate)
142 {
143 Status = AE_CTRL_TRUE;
144 }
145
146 break;
147
148 case AML_RETURN_OP:
149
150 break;
151
152 default:
153 break;
154 }
155
156 return (Status);
157 }
158
159
160 /*******************************************************************************
161 *
162 * FUNCTION: AcpiDsExecEndControlOp
163 *
164 * PARAMETERS: WalkList - The list that owns the walk stack
165 * Op - The control Op
166 *
167 * RETURN: Status
168 *
169 * DESCRIPTION: Handles all control ops encountered during control method
170 * execution.
171 *
172 ******************************************************************************/
187 {
188 case AML_IF_OP:
189
190 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "[IF_OP] Op=%p\n", Op));
191
192 /*
193 * Save the result of the predicate in case there is an
194 * ELSE to come
195 */
196 WalkState->LastPredicate =
197 (BOOLEAN) WalkState->ControlState->Common.Value;
198
199 /*
200 * Pop the control state that was created at the start
201 * of the IF and free it
202 */
203 ControlState = AcpiUtPopGenericState (&WalkState->ControlState);
204 AcpiUtDeleteGenericState (ControlState);
205 break;
206
207
208 case AML_ELSE_OP:
209
210 break;
211
212
213 case AML_WHILE_OP:
214
215 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "[WHILE_OP] Op=%p\n", Op));
216
217 ControlState = WalkState->ControlState;
218 if (ControlState->Common.Value)
219 {
220 /* Predicate was true, the body of the loop was just executed */
221
222 /*
223 * This loop counter mechanism allows the interpreter to escape
224 * possibly infinite loops. This can occur in poorly written AML
225 * when the hardware does not respond within a while loop and the
226 * loop does not implement a timeout.
227 */
228 ControlState->Control.LoopCount++;
229 if (ControlState->Control.LoopCount > ACPI_MAX_LOOP_ITERATIONS)
230 {
231 Status = AE_AML_INFINITE_LOOP;
232 break;
235 /*
236 * Go back and evaluate the predicate and maybe execute the loop
237 * another time
238 */
239 Status = AE_CTRL_PENDING;
240 WalkState->AmlLastWhile = ControlState->Control.AmlPredicateStart;
241 break;
242 }
243
244 /* Predicate was false, terminate this while loop */
245
246 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
247 "[WHILE_OP] termination! Op=%p\n",Op));
248
249 /* Pop this control state and free it */
250
251 ControlState = AcpiUtPopGenericState (&WalkState->ControlState);
252 AcpiUtDeleteGenericState (ControlState);
253 break;
254
255
256 case AML_RETURN_OP:
257
258 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
259 "[RETURN_OP] Op=%p Arg=%p\n",Op, Op->Common.Value.Arg));
260
261 /*
262 * One optional operand -- the return value
263 * It can be either an immediate operand or a result that
264 * has been bubbled up the tree
265 */
266 if (Op->Common.Value.Arg)
267 {
268 /* Since we have a real Return(), delete any implicit return */
269
270 AcpiDsClearImplicitReturn (WalkState);
271
272 /* Return statement has an immediate operand */
273
274 Status = AcpiDsCreateOperands (WalkState, Op->Common.Value.Arg);
275 if (ACPI_FAILURE (Status))
331 if (WalkState->NumOperands)
332 {
333 AcpiUtRemoveReference (WalkState->Operands [0]);
334 }
335
336 WalkState->Operands [0] = NULL;
337 WalkState->NumOperands = 0;
338 WalkState->ReturnDesc = NULL;
339 }
340
341
342 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
343 "Completed RETURN_OP State=%p, RetVal=%p\n",
344 WalkState, WalkState->ReturnDesc));
345
346 /* End the control method execution right now */
347
348 Status = AE_CTRL_TERMINATE;
349 break;
350
351
352 case AML_NOOP_OP:
353
354 /* Just do nothing! */
355 break;
356
357
358 case AML_BREAK_POINT_OP:
359
360 /*
361 * Set the single-step flag. This will cause the debugger (if present)
362 * to break to the console within the AML debugger at the start of the
363 * next AML instruction.
364 */
365 ACPI_DEBUGGER_EXEC (
366 AcpiGbl_CmSingleStep = TRUE);
367 ACPI_DEBUGGER_EXEC (
368 AcpiOsPrintf ("**break** Executed AML BreakPoint opcode\n"));
369
370 /* Call to the OSL in case OS wants a piece of the action */
371
372 Status = AcpiOsSignal (ACPI_SIGNAL_BREAKPOINT,
373 "Executed AML Breakpoint opcode");
374 break;
375
376
377 case AML_BREAK_OP:
378 case AML_CONTINUE_OP: /* ACPI 2.0 */
379
380
381 /* Pop and delete control states until we find a while */
382
383 while (WalkState->ControlState &&
384 (WalkState->ControlState->Control.Opcode != AML_WHILE_OP))
385 {
386 ControlState = AcpiUtPopGenericState (&WalkState->ControlState);
387 AcpiUtDeleteGenericState (ControlState);
388 }
389
390 /* No while found? */
391
392 if (!WalkState->ControlState)
393 {
394 return (AE_AML_NO_WHILE);
395 }
396
397 /* Was: WalkState->AmlLastWhile = WalkState->ControlState->Control.AmlPredicateStart; */
398
399 WalkState->AmlLastWhile = WalkState->ControlState->Control.PackageEnd;
400
401 /* Return status depending on opcode */
402
403 if (Op->Common.AmlOpcode == AML_BREAK_OP)
404 {
405 Status = AE_CTRL_BREAK;
406 }
407 else
408 {
409 Status = AE_CTRL_CONTINUE;
410 }
411 break;
412
413
414 default:
415
416 ACPI_ERROR ((AE_INFO, "Unknown control opcode=0x%X Op=%p",
417 Op->Common.AmlOpcode, Op));
418
419 Status = AE_AML_BAD_OPCODE;
420 break;
421 }
422
423 return (Status);
424 }
|
1 /******************************************************************************
2 *
3 * Module Name: dscontrol - Support for execution control opcodes -
4 * if/else/while/return
5 *
6 *****************************************************************************/
7
8 /*
9 * Copyright (C) 2000 - 2013, Intel Corp.
10 * All rights reserved.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions, and the following disclaimer,
17 * without modification.
18 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19 * substantially similar to the "NO WARRANTY" disclaimer below
20 * ("Disclaimer") and any redistribution must be conditioned upon
21 * including a substantially similar Disclaimer requirement for further
22 * binary redistribution.
23 * 3. Neither the names of the above-listed copyright holders nor the names
24 * of any contributors may be used to endorse or promote products derived
25 * from this software without specific prior written permission.
26 *
27 * Alternatively, this software may be distributed under the terms of the
28 * GNU General Public License ("GPL") version 2 as published by the Free
29 * Software Foundation.
69 ******************************************************************************/
70
71 ACPI_STATUS
72 AcpiDsExecBeginControlOp (
73 ACPI_WALK_STATE *WalkState,
74 ACPI_PARSE_OBJECT *Op)
75 {
76 ACPI_STATUS Status = AE_OK;
77 ACPI_GENERIC_STATE *ControlState;
78
79
80 ACPI_FUNCTION_NAME (DsExecBeginControlOp);
81
82
83 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Op=%p Opcode=%2.2X State=%p\n",
84 Op, Op->Common.AmlOpcode, WalkState));
85
86 switch (Op->Common.AmlOpcode)
87 {
88 case AML_WHILE_OP:
89 /*
90 * If this is an additional iteration of a while loop, continue.
91 * There is no need to allocate a new control state.
92 */
93 if (WalkState->ControlState)
94 {
95 if (WalkState->ControlState->Control.AmlPredicateStart ==
96 (WalkState->ParserState.Aml - 1))
97 {
98 /* Reset the state to start-of-loop */
99
100 WalkState->ControlState->Common.State =
101 ACPI_CONTROL_CONDITIONAL_EXECUTING;
102 break;
103 }
104 }
105
106 /*lint -fallthrough */
107
108 case AML_IF_OP:
109 /*
110 * IF/WHILE: Create a new control state to manage these
111 * constructs. We need to manage these as a stack, in order
112 * to handle nesting.
113 */
114 ControlState = AcpiUtCreateControlState ();
115 if (!ControlState)
116 {
117 Status = AE_NO_MEMORY;
118 break;
119 }
120 /*
121 * Save a pointer to the predicate for multiple executions
122 * of a loop
123 */
124 ControlState->Control.AmlPredicateStart = WalkState->ParserState.Aml - 1;
125 ControlState->Control.PackageEnd = WalkState->ParserState.PkgEnd;
126 ControlState->Control.Opcode = Op->Common.AmlOpcode;
127
128
131 AcpiUtPushGenericState (&WalkState->ControlState, ControlState);
132 break;
133
134 case AML_ELSE_OP:
135
136 /* Predicate is in the state object */
137 /* If predicate is true, the IF was executed, ignore ELSE part */
138
139 if (WalkState->LastPredicate)
140 {
141 Status = AE_CTRL_TRUE;
142 }
143
144 break;
145
146 case AML_RETURN_OP:
147
148 break;
149
150 default:
151
152 break;
153 }
154
155 return (Status);
156 }
157
158
159 /*******************************************************************************
160 *
161 * FUNCTION: AcpiDsExecEndControlOp
162 *
163 * PARAMETERS: WalkList - The list that owns the walk stack
164 * Op - The control Op
165 *
166 * RETURN: Status
167 *
168 * DESCRIPTION: Handles all control ops encountered during control method
169 * execution.
170 *
171 ******************************************************************************/
186 {
187 case AML_IF_OP:
188
189 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "[IF_OP] Op=%p\n", Op));
190
191 /*
192 * Save the result of the predicate in case there is an
193 * ELSE to come
194 */
195 WalkState->LastPredicate =
196 (BOOLEAN) WalkState->ControlState->Common.Value;
197
198 /*
199 * Pop the control state that was created at the start
200 * of the IF and free it
201 */
202 ControlState = AcpiUtPopGenericState (&WalkState->ControlState);
203 AcpiUtDeleteGenericState (ControlState);
204 break;
205
206 case AML_ELSE_OP:
207
208 break;
209
210 case AML_WHILE_OP:
211
212 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "[WHILE_OP] Op=%p\n", Op));
213
214 ControlState = WalkState->ControlState;
215 if (ControlState->Common.Value)
216 {
217 /* Predicate was true, the body of the loop was just executed */
218
219 /*
220 * This loop counter mechanism allows the interpreter to escape
221 * possibly infinite loops. This can occur in poorly written AML
222 * when the hardware does not respond within a while loop and the
223 * loop does not implement a timeout.
224 */
225 ControlState->Control.LoopCount++;
226 if (ControlState->Control.LoopCount > ACPI_MAX_LOOP_ITERATIONS)
227 {
228 Status = AE_AML_INFINITE_LOOP;
229 break;
232 /*
233 * Go back and evaluate the predicate and maybe execute the loop
234 * another time
235 */
236 Status = AE_CTRL_PENDING;
237 WalkState->AmlLastWhile = ControlState->Control.AmlPredicateStart;
238 break;
239 }
240
241 /* Predicate was false, terminate this while loop */
242
243 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
244 "[WHILE_OP] termination! Op=%p\n",Op));
245
246 /* Pop this control state and free it */
247
248 ControlState = AcpiUtPopGenericState (&WalkState->ControlState);
249 AcpiUtDeleteGenericState (ControlState);
250 break;
251
252 case AML_RETURN_OP:
253
254 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
255 "[RETURN_OP] Op=%p Arg=%p\n",Op, Op->Common.Value.Arg));
256
257 /*
258 * One optional operand -- the return value
259 * It can be either an immediate operand or a result that
260 * has been bubbled up the tree
261 */
262 if (Op->Common.Value.Arg)
263 {
264 /* Since we have a real Return(), delete any implicit return */
265
266 AcpiDsClearImplicitReturn (WalkState);
267
268 /* Return statement has an immediate operand */
269
270 Status = AcpiDsCreateOperands (WalkState, Op->Common.Value.Arg);
271 if (ACPI_FAILURE (Status))
327 if (WalkState->NumOperands)
328 {
329 AcpiUtRemoveReference (WalkState->Operands [0]);
330 }
331
332 WalkState->Operands [0] = NULL;
333 WalkState->NumOperands = 0;
334 WalkState->ReturnDesc = NULL;
335 }
336
337
338 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
339 "Completed RETURN_OP State=%p, RetVal=%p\n",
340 WalkState, WalkState->ReturnDesc));
341
342 /* End the control method execution right now */
343
344 Status = AE_CTRL_TERMINATE;
345 break;
346
347 case AML_NOOP_OP:
348
349 /* Just do nothing! */
350
351 break;
352
353 case AML_BREAK_POINT_OP:
354
355 /*
356 * Set the single-step flag. This will cause the debugger (if present)
357 * to break to the console within the AML debugger at the start of the
358 * next AML instruction.
359 */
360 ACPI_DEBUGGER_EXEC (
361 AcpiGbl_CmSingleStep = TRUE);
362 ACPI_DEBUGGER_EXEC (
363 AcpiOsPrintf ("**break** Executed AML BreakPoint opcode\n"));
364
365 /* Call to the OSL in case OS wants a piece of the action */
366
367 Status = AcpiOsSignal (ACPI_SIGNAL_BREAKPOINT,
368 "Executed AML Breakpoint opcode");
369 break;
370
371 case AML_BREAK_OP:
372 case AML_CONTINUE_OP: /* ACPI 2.0 */
373
374 /* Pop and delete control states until we find a while */
375
376 while (WalkState->ControlState &&
377 (WalkState->ControlState->Control.Opcode != AML_WHILE_OP))
378 {
379 ControlState = AcpiUtPopGenericState (&WalkState->ControlState);
380 AcpiUtDeleteGenericState (ControlState);
381 }
382
383 /* No while found? */
384
385 if (!WalkState->ControlState)
386 {
387 return (AE_AML_NO_WHILE);
388 }
389
390 /* Was: WalkState->AmlLastWhile = WalkState->ControlState->Control.AmlPredicateStart; */
391
392 WalkState->AmlLastWhile = WalkState->ControlState->Control.PackageEnd;
393
394 /* Return status depending on opcode */
395
396 if (Op->Common.AmlOpcode == AML_BREAK_OP)
397 {
398 Status = AE_CTRL_BREAK;
399 }
400 else
401 {
402 Status = AE_CTRL_CONTINUE;
403 }
404 break;
405
406 default:
407
408 ACPI_ERROR ((AE_INFO, "Unknown control opcode=0x%X Op=%p",
409 Op->Common.AmlOpcode, Op));
410
411 Status = AE_AML_BAD_OPCODE;
412 break;
413 }
414
415 return (Status);
416 }
|