xref: /openbmc/linux/drivers/acpi/acpica/exmisc.c (revision 7587eb18)
1 /******************************************************************************
2  *
3  * Module Name: exmisc - ACPI AML (p-code) execution - specific opcodes
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2016, 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 "acinterp.h"
47 #include "amlcode.h"
48 
49 #define _COMPONENT          ACPI_EXECUTER
50 ACPI_MODULE_NAME("exmisc")
51 
52 /*******************************************************************************
53  *
54  * FUNCTION:    acpi_ex_get_object_reference
55  *
56  * PARAMETERS:  obj_desc            - Create a reference to this object
57  *              return_desc         - Where to store the reference
58  *              walk_state          - Current state
59  *
60  * RETURN:      Status
61  *
62  * DESCRIPTION: Obtain and return a "reference" to the target object
63  *              Common code for the ref_of_op and the cond_ref_of_op.
64  *
65  ******************************************************************************/
66 acpi_status
67 acpi_ex_get_object_reference(union acpi_operand_object *obj_desc,
68 			     union acpi_operand_object **return_desc,
69 			     struct acpi_walk_state *walk_state)
70 {
71 	union acpi_operand_object *reference_obj;
72 	union acpi_operand_object *referenced_obj;
73 
74 	ACPI_FUNCTION_TRACE_PTR(ex_get_object_reference, obj_desc);
75 
76 	*return_desc = NULL;
77 
78 	switch (ACPI_GET_DESCRIPTOR_TYPE(obj_desc)) {
79 	case ACPI_DESC_TYPE_OPERAND:
80 
81 		if (obj_desc->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
82 			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
83 		}
84 
85 		/*
86 		 * Must be a reference to a Local or Arg
87 		 */
88 		switch (obj_desc->reference.class) {
89 		case ACPI_REFCLASS_LOCAL:
90 		case ACPI_REFCLASS_ARG:
91 		case ACPI_REFCLASS_DEBUG:
92 
93 			/* The referenced object is the pseudo-node for the local/arg */
94 
95 			referenced_obj = obj_desc->reference.object;
96 			break;
97 
98 		default:
99 
100 			ACPI_ERROR((AE_INFO, "Invalid Reference Class 0x%2.2X",
101 				    obj_desc->reference.class));
102 			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
103 		}
104 		break;
105 
106 	case ACPI_DESC_TYPE_NAMED:
107 		/*
108 		 * A named reference that has already been resolved to a Node
109 		 */
110 		referenced_obj = obj_desc;
111 		break;
112 
113 	default:
114 
115 		ACPI_ERROR((AE_INFO, "Invalid descriptor type 0x%X",
116 			    ACPI_GET_DESCRIPTOR_TYPE(obj_desc)));
117 		return_ACPI_STATUS(AE_TYPE);
118 	}
119 
120 	/* Create a new reference object */
121 
122 	reference_obj =
123 	    acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_REFERENCE);
124 	if (!reference_obj) {
125 		return_ACPI_STATUS(AE_NO_MEMORY);
126 	}
127 
128 	reference_obj->reference.class = ACPI_REFCLASS_REFOF;
129 	reference_obj->reference.object = referenced_obj;
130 	*return_desc = reference_obj;
131 
132 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
133 			  "Object %p Type [%s], returning Reference %p\n",
134 			  obj_desc, acpi_ut_get_object_type_name(obj_desc),
135 			  *return_desc));
136 
137 	return_ACPI_STATUS(AE_OK);
138 }
139 
140 /*******************************************************************************
141  *
142  * FUNCTION:    acpi_ex_do_math_op
143  *
144  * PARAMETERS:  opcode              - AML opcode
145  *              integer0            - Integer operand #0
146  *              integer1            - Integer operand #1
147  *
148  * RETURN:      Integer result of the operation
149  *
150  * DESCRIPTION: Execute a math AML opcode. The purpose of having all of the
151  *              math functions here is to prevent a lot of pointer dereferencing
152  *              to obtain the operands.
153  *
154  ******************************************************************************/
155 
156 u64 acpi_ex_do_math_op(u16 opcode, u64 integer0, u64 integer1)
157 {
158 
159 	ACPI_FUNCTION_ENTRY();
160 
161 	switch (opcode) {
162 	case AML_ADD_OP:	/* Add (Integer0, Integer1, Result) */
163 
164 		return (integer0 + integer1);
165 
166 	case AML_BIT_AND_OP:	/* And (Integer0, Integer1, Result) */
167 
168 		return (integer0 & integer1);
169 
170 	case AML_BIT_NAND_OP:	/* NAnd (Integer0, Integer1, Result) */
171 
172 		return (~(integer0 & integer1));
173 
174 	case AML_BIT_OR_OP:	/* Or (Integer0, Integer1, Result) */
175 
176 		return (integer0 | integer1);
177 
178 	case AML_BIT_NOR_OP:	/* NOr (Integer0, Integer1, Result) */
179 
180 		return (~(integer0 | integer1));
181 
182 	case AML_BIT_XOR_OP:	/* XOr (Integer0, Integer1, Result) */
183 
184 		return (integer0 ^ integer1);
185 
186 	case AML_MULTIPLY_OP:	/* Multiply (Integer0, Integer1, Result) */
187 
188 		return (integer0 * integer1);
189 
190 	case AML_SHIFT_LEFT_OP:	/* shift_left (Operand, shift_count, Result) */
191 
192 		/*
193 		 * We need to check if the shiftcount is larger than the integer bit
194 		 * width since the behavior of this is not well-defined in the C language.
195 		 */
196 		if (integer1 >= acpi_gbl_integer_bit_width) {
197 			return (0);
198 		}
199 		return (integer0 << integer1);
200 
201 	case AML_SHIFT_RIGHT_OP:	/* shift_right (Operand, shift_count, Result) */
202 
203 		/*
204 		 * We need to check if the shiftcount is larger than the integer bit
205 		 * width since the behavior of this is not well-defined in the C language.
206 		 */
207 		if (integer1 >= acpi_gbl_integer_bit_width) {
208 			return (0);
209 		}
210 		return (integer0 >> integer1);
211 
212 	case AML_SUBTRACT_OP:	/* Subtract (Integer0, Integer1, Result) */
213 
214 		return (integer0 - integer1);
215 
216 	default:
217 
218 		return (0);
219 	}
220 }
221 
222 /*******************************************************************************
223  *
224  * FUNCTION:    acpi_ex_do_logical_numeric_op
225  *
226  * PARAMETERS:  opcode              - AML opcode
227  *              integer0            - Integer operand #0
228  *              integer1            - Integer operand #1
229  *              logical_result      - TRUE/FALSE result of the operation
230  *
231  * RETURN:      Status
232  *
233  * DESCRIPTION: Execute a logical "Numeric" AML opcode. For these Numeric
234  *              operators (LAnd and LOr), both operands must be integers.
235  *
236  *              Note: cleanest machine code seems to be produced by the code
237  *              below, rather than using statements of the form:
238  *                  Result = (Integer0 && Integer1);
239  *
240  ******************************************************************************/
241 
242 acpi_status
243 acpi_ex_do_logical_numeric_op(u16 opcode,
244 			      u64 integer0, u64 integer1, u8 *logical_result)
245 {
246 	acpi_status status = AE_OK;
247 	u8 local_result = FALSE;
248 
249 	ACPI_FUNCTION_TRACE(ex_do_logical_numeric_op);
250 
251 	switch (opcode) {
252 	case AML_LAND_OP:	/* LAnd (Integer0, Integer1) */
253 
254 		if (integer0 && integer1) {
255 			local_result = TRUE;
256 		}
257 		break;
258 
259 	case AML_LOR_OP:	/* LOr (Integer0, Integer1) */
260 
261 		if (integer0 || integer1) {
262 			local_result = TRUE;
263 		}
264 		break;
265 
266 	default:
267 
268 		status = AE_AML_INTERNAL;
269 		break;
270 	}
271 
272 	/* Return the logical result and status */
273 
274 	*logical_result = local_result;
275 	return_ACPI_STATUS(status);
276 }
277 
278 /*******************************************************************************
279  *
280  * FUNCTION:    acpi_ex_do_logical_op
281  *
282  * PARAMETERS:  opcode              - AML opcode
283  *              operand0            - operand #0
284  *              operand1            - operand #1
285  *              logical_result      - TRUE/FALSE result of the operation
286  *
287  * RETURN:      Status
288  *
289  * DESCRIPTION: Execute a logical AML opcode. The purpose of having all of the
290  *              functions here is to prevent a lot of pointer dereferencing
291  *              to obtain the operands and to simplify the generation of the
292  *              logical value. For the Numeric operators (LAnd and LOr), both
293  *              operands must be integers. For the other logical operators,
294  *              operands can be any combination of Integer/String/Buffer. The
295  *              first operand determines the type to which the second operand
296  *              will be converted.
297  *
298  *              Note: cleanest machine code seems to be produced by the code
299  *              below, rather than using statements of the form:
300  *                  Result = (Operand0 == Operand1);
301  *
302  ******************************************************************************/
303 
304 acpi_status
305 acpi_ex_do_logical_op(u16 opcode,
306 		      union acpi_operand_object *operand0,
307 		      union acpi_operand_object *operand1, u8 * logical_result)
308 {
309 	union acpi_operand_object *local_operand1 = operand1;
310 	u64 integer0;
311 	u64 integer1;
312 	u32 length0;
313 	u32 length1;
314 	acpi_status status = AE_OK;
315 	u8 local_result = FALSE;
316 	int compare;
317 
318 	ACPI_FUNCTION_TRACE(ex_do_logical_op);
319 
320 	/*
321 	 * Convert the second operand if necessary. The first operand
322 	 * determines the type of the second operand, (See the Data Types
323 	 * section of the ACPI 3.0+ specification.)  Both object types are
324 	 * guaranteed to be either Integer/String/Buffer by the operand
325 	 * resolution mechanism.
326 	 */
327 	switch (operand0->common.type) {
328 	case ACPI_TYPE_INTEGER:
329 
330 		status =
331 		    acpi_ex_convert_to_integer(operand1, &local_operand1, 16);
332 		break;
333 
334 	case ACPI_TYPE_STRING:
335 
336 		status =
337 		    acpi_ex_convert_to_string(operand1, &local_operand1,
338 					      ACPI_IMPLICIT_CONVERT_HEX);
339 		break;
340 
341 	case ACPI_TYPE_BUFFER:
342 
343 		status = acpi_ex_convert_to_buffer(operand1, &local_operand1);
344 		break;
345 
346 	default:
347 
348 		status = AE_AML_INTERNAL;
349 		break;
350 	}
351 
352 	if (ACPI_FAILURE(status)) {
353 		goto cleanup;
354 	}
355 
356 	/*
357 	 * Two cases: 1) Both Integers, 2) Both Strings or Buffers
358 	 */
359 	if (operand0->common.type == ACPI_TYPE_INTEGER) {
360 		/*
361 		 * 1) Both operands are of type integer
362 		 *    Note: local_operand1 may have changed above
363 		 */
364 		integer0 = operand0->integer.value;
365 		integer1 = local_operand1->integer.value;
366 
367 		switch (opcode) {
368 		case AML_LEQUAL_OP:	/* LEqual (Operand0, Operand1) */
369 
370 			if (integer0 == integer1) {
371 				local_result = TRUE;
372 			}
373 			break;
374 
375 		case AML_LGREATER_OP:	/* LGreater (Operand0, Operand1) */
376 
377 			if (integer0 > integer1) {
378 				local_result = TRUE;
379 			}
380 			break;
381 
382 		case AML_LLESS_OP:	/* LLess (Operand0, Operand1) */
383 
384 			if (integer0 < integer1) {
385 				local_result = TRUE;
386 			}
387 			break;
388 
389 		default:
390 
391 			status = AE_AML_INTERNAL;
392 			break;
393 		}
394 	} else {
395 		/*
396 		 * 2) Both operands are Strings or both are Buffers
397 		 *    Note: Code below takes advantage of common Buffer/String
398 		 *          object fields. local_operand1 may have changed above. Use
399 		 *          memcmp to handle nulls in buffers.
400 		 */
401 		length0 = operand0->buffer.length;
402 		length1 = local_operand1->buffer.length;
403 
404 		/* Lexicographic compare: compare the data bytes */
405 
406 		compare = memcmp(operand0->buffer.pointer,
407 				 local_operand1->buffer.pointer,
408 				 (length0 > length1) ? length1 : length0);
409 
410 		switch (opcode) {
411 		case AML_LEQUAL_OP:	/* LEqual (Operand0, Operand1) */
412 
413 			/* Length and all bytes must be equal */
414 
415 			if ((length0 == length1) && (compare == 0)) {
416 
417 				/* Length and all bytes match ==> TRUE */
418 
419 				local_result = TRUE;
420 			}
421 			break;
422 
423 		case AML_LGREATER_OP:	/* LGreater (Operand0, Operand1) */
424 
425 			if (compare > 0) {
426 				local_result = TRUE;
427 				goto cleanup;	/* TRUE */
428 			}
429 			if (compare < 0) {
430 				goto cleanup;	/* FALSE */
431 			}
432 
433 			/* Bytes match (to shortest length), compare lengths */
434 
435 			if (length0 > length1) {
436 				local_result = TRUE;
437 			}
438 			break;
439 
440 		case AML_LLESS_OP:	/* LLess (Operand0, Operand1) */
441 
442 			if (compare > 0) {
443 				goto cleanup;	/* FALSE */
444 			}
445 			if (compare < 0) {
446 				local_result = TRUE;
447 				goto cleanup;	/* TRUE */
448 			}
449 
450 			/* Bytes match (to shortest length), compare lengths */
451 
452 			if (length0 < length1) {
453 				local_result = TRUE;
454 			}
455 			break;
456 
457 		default:
458 
459 			status = AE_AML_INTERNAL;
460 			break;
461 		}
462 	}
463 
464 cleanup:
465 
466 	/* New object was created if implicit conversion performed - delete */
467 
468 	if (local_operand1 != operand1) {
469 		acpi_ut_remove_reference(local_operand1);
470 	}
471 
472 	/* Return the logical result and status */
473 
474 	*logical_result = local_result;
475 	return_ACPI_STATUS(status);
476 }
477