1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2/******************************************************************************
3 *
4 * Module Name: exmisc - ACPI AML (p-code) execution - specific opcodes
5 *
6 * Copyright (C) 2000 - 2023, Intel Corp.
7 *
8 *****************************************************************************/
9
10#include <acpi/acpi.h>
11#include "accommon.h"
12#include "acinterp.h"
13#include "amlcode.h"
14
15#define _COMPONENT          ACPI_EXECUTER
16ACPI_MODULE_NAME("exmisc")
17
18/*******************************************************************************
19 *
20 * FUNCTION:    acpi_ex_get_object_reference
21 *
22 * PARAMETERS:  obj_desc            - Create a reference to this object
23 *              return_desc         - Where to store the reference
24 *              walk_state          - Current state
25 *
26 * RETURN:      Status
27 *
28 * DESCRIPTION: Obtain and return a "reference" to the target object
29 *              Common code for the ref_of_op and the cond_ref_of_op.
30 *
31 ******************************************************************************/
32acpi_status
33acpi_ex_get_object_reference(union acpi_operand_object *obj_desc,
34			     union acpi_operand_object **return_desc,
35			     struct acpi_walk_state *walk_state)
36{
37	union acpi_operand_object *reference_obj;
38	union acpi_operand_object *referenced_obj;
39
40	ACPI_FUNCTION_TRACE_PTR(ex_get_object_reference, obj_desc);
41
42	*return_desc = NULL;
43
44	switch (ACPI_GET_DESCRIPTOR_TYPE(obj_desc)) {
45	case ACPI_DESC_TYPE_OPERAND:
46
47		if (obj_desc->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
48			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
49		}
50
51		/*
52		 * Must be a reference to a Local or Arg
53		 */
54		switch (obj_desc->reference.class) {
55		case ACPI_REFCLASS_LOCAL:
56		case ACPI_REFCLASS_ARG:
57		case ACPI_REFCLASS_DEBUG:
58
59			/* The referenced object is the pseudo-node for the local/arg */
60
61			referenced_obj = obj_desc->reference.object;
62			break;
63
64		default:
65
66			ACPI_ERROR((AE_INFO, "Invalid Reference Class 0x%2.2X",
67				    obj_desc->reference.class));
68			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
69		}
70		break;
71
72	case ACPI_DESC_TYPE_NAMED:
73		/*
74		 * A named reference that has already been resolved to a Node
75		 */
76		referenced_obj = obj_desc;
77		break;
78
79	default:
80
81		ACPI_ERROR((AE_INFO, "Invalid descriptor type 0x%X",
82			    ACPI_GET_DESCRIPTOR_TYPE(obj_desc)));
83		return_ACPI_STATUS(AE_TYPE);
84	}
85
86	/* Create a new reference object */
87
88	reference_obj =
89	    acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_REFERENCE);
90	if (!reference_obj) {
91		return_ACPI_STATUS(AE_NO_MEMORY);
92	}
93
94	reference_obj->reference.class = ACPI_REFCLASS_REFOF;
95	reference_obj->reference.object = referenced_obj;
96	*return_desc = reference_obj;
97
98	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
99			  "Object %p Type [%s], returning Reference %p\n",
100			  obj_desc, acpi_ut_get_object_type_name(obj_desc),
101			  *return_desc));
102
103	return_ACPI_STATUS(AE_OK);
104}
105
106/*******************************************************************************
107 *
108 * FUNCTION:    acpi_ex_do_math_op
109 *
110 * PARAMETERS:  opcode              - AML opcode
111 *              integer0            - Integer operand #0
112 *              integer1            - Integer operand #1
113 *
114 * RETURN:      Integer result of the operation
115 *
116 * DESCRIPTION: Execute a math AML opcode. The purpose of having all of the
117 *              math functions here is to prevent a lot of pointer dereferencing
118 *              to obtain the operands.
119 *
120 ******************************************************************************/
121
122u64 acpi_ex_do_math_op(u16 opcode, u64 integer0, u64 integer1)
123{
124
125	ACPI_FUNCTION_ENTRY();
126
127	switch (opcode) {
128	case AML_ADD_OP:	/* Add (Integer0, Integer1, Result) */
129
130		return (integer0 + integer1);
131
132	case AML_BIT_AND_OP:	/* And (Integer0, Integer1, Result) */
133
134		return (integer0 & integer1);
135
136	case AML_BIT_NAND_OP:	/* NAnd (Integer0, Integer1, Result) */
137
138		return (~(integer0 & integer1));
139
140	case AML_BIT_OR_OP:	/* Or (Integer0, Integer1, Result) */
141
142		return (integer0 | integer1);
143
144	case AML_BIT_NOR_OP:	/* NOr (Integer0, Integer1, Result) */
145
146		return (~(integer0 | integer1));
147
148	case AML_BIT_XOR_OP:	/* XOr (Integer0, Integer1, Result) */
149
150		return (integer0 ^ integer1);
151
152	case AML_MULTIPLY_OP:	/* Multiply (Integer0, Integer1, Result) */
153
154		return (integer0 * integer1);
155
156	case AML_SHIFT_LEFT_OP:	/* shift_left (Operand, shift_count, Result) */
157
158		/*
159		 * We need to check if the shiftcount is larger than the integer bit
160		 * width since the behavior of this is not well-defined in the C language.
161		 */
162		if (integer1 >= acpi_gbl_integer_bit_width) {
163			return (0);
164		}
165		return (integer0 << integer1);
166
167	case AML_SHIFT_RIGHT_OP:	/* shift_right (Operand, shift_count, Result) */
168
169		/*
170		 * We need to check if the shiftcount is larger than the integer bit
171		 * width since the behavior of this is not well-defined in the C language.
172		 */
173		if (integer1 >= acpi_gbl_integer_bit_width) {
174			return (0);
175		}
176		return (integer0 >> integer1);
177
178	case AML_SUBTRACT_OP:	/* Subtract (Integer0, Integer1, Result) */
179
180		return (integer0 - integer1);
181
182	default:
183
184		return (0);
185	}
186}
187
188/*******************************************************************************
189 *
190 * FUNCTION:    acpi_ex_do_logical_numeric_op
191 *
192 * PARAMETERS:  opcode              - AML opcode
193 *              integer0            - Integer operand #0
194 *              integer1            - Integer operand #1
195 *              logical_result      - TRUE/FALSE result of the operation
196 *
197 * RETURN:      Status
198 *
199 * DESCRIPTION: Execute a logical "Numeric" AML opcode. For these Numeric
200 *              operators (LAnd and LOr), both operands must be integers.
201 *
202 *              Note: cleanest machine code seems to be produced by the code
203 *              below, rather than using statements of the form:
204 *                  Result = (Integer0 && Integer1);
205 *
206 ******************************************************************************/
207
208acpi_status
209acpi_ex_do_logical_numeric_op(u16 opcode,
210			      u64 integer0, u64 integer1, u8 *logical_result)
211{
212	acpi_status status = AE_OK;
213	u8 local_result = FALSE;
214
215	ACPI_FUNCTION_TRACE(ex_do_logical_numeric_op);
216
217	switch (opcode) {
218	case AML_LOGICAL_AND_OP:	/* LAnd (Integer0, Integer1) */
219
220		if (integer0 && integer1) {
221			local_result = TRUE;
222		}
223		break;
224
225	case AML_LOGICAL_OR_OP:	/* LOr (Integer0, Integer1) */
226
227		if (integer0 || integer1) {
228			local_result = TRUE;
229		}
230		break;
231
232	default:
233
234		ACPI_ERROR((AE_INFO,
235			    "Invalid numeric logical opcode: %X", opcode));
236		status = AE_AML_INTERNAL;
237		break;
238	}
239
240	/* Return the logical result and status */
241
242	*logical_result = local_result;
243	return_ACPI_STATUS(status);
244}
245
246/*******************************************************************************
247 *
248 * FUNCTION:    acpi_ex_do_logical_op
249 *
250 * PARAMETERS:  opcode              - AML opcode
251 *              operand0            - operand #0
252 *              operand1            - operand #1
253 *              logical_result      - TRUE/FALSE result of the operation
254 *
255 * RETURN:      Status
256 *
257 * DESCRIPTION: Execute a logical AML opcode. The purpose of having all of the
258 *              functions here is to prevent a lot of pointer dereferencing
259 *              to obtain the operands and to simplify the generation of the
260 *              logical value. For the Numeric operators (LAnd and LOr), both
261 *              operands must be integers. For the other logical operators,
262 *              operands can be any combination of Integer/String/Buffer. The
263 *              first operand determines the type to which the second operand
264 *              will be converted.
265 *
266 *              Note: cleanest machine code seems to be produced by the code
267 *              below, rather than using statements of the form:
268 *                  Result = (Operand0 == Operand1);
269 *
270 ******************************************************************************/
271
272acpi_status
273acpi_ex_do_logical_op(u16 opcode,
274		      union acpi_operand_object *operand0,
275		      union acpi_operand_object *operand1, u8 * logical_result)
276{
277	union acpi_operand_object *local_operand1 = operand1;
278	u64 integer0;
279	u64 integer1;
280	u32 length0;
281	u32 length1;
282	acpi_status status = AE_OK;
283	u8 local_result = FALSE;
284	int compare;
285
286	ACPI_FUNCTION_TRACE(ex_do_logical_op);
287
288	/*
289	 * Convert the second operand if necessary. The first operand
290	 * determines the type of the second operand, (See the Data Types
291	 * section of the ACPI 3.0+ specification.)  Both object types are
292	 * guaranteed to be either Integer/String/Buffer by the operand
293	 * resolution mechanism.
294	 */
295	switch (operand0->common.type) {
296	case ACPI_TYPE_INTEGER:
297
298		status = acpi_ex_convert_to_integer(operand1, &local_operand1,
299						    ACPI_IMPLICIT_CONVERSION);
300		break;
301
302	case ACPI_TYPE_STRING:
303
304		status =
305		    acpi_ex_convert_to_string(operand1, &local_operand1,
306					      ACPI_IMPLICIT_CONVERT_HEX);
307		break;
308
309	case ACPI_TYPE_BUFFER:
310
311		status = acpi_ex_convert_to_buffer(operand1, &local_operand1);
312		break;
313
314	default:
315
316		ACPI_ERROR((AE_INFO,
317			    "Invalid object type for logical operator: %X",
318			    operand0->common.type));
319		status = AE_AML_INTERNAL;
320		break;
321	}
322
323	if (ACPI_FAILURE(status)) {
324		goto cleanup;
325	}
326
327	/*
328	 * Two cases: 1) Both Integers, 2) Both Strings or Buffers
329	 */
330	if (operand0->common.type == ACPI_TYPE_INTEGER) {
331		/*
332		 * 1) Both operands are of type integer
333		 *    Note: local_operand1 may have changed above
334		 */
335		integer0 = operand0->integer.value;
336		integer1 = local_operand1->integer.value;
337
338		switch (opcode) {
339		case AML_LOGICAL_EQUAL_OP:	/* LEqual (Operand0, Operand1) */
340
341			if (integer0 == integer1) {
342				local_result = TRUE;
343			}
344			break;
345
346		case AML_LOGICAL_GREATER_OP:	/* LGreater (Operand0, Operand1) */
347
348			if (integer0 > integer1) {
349				local_result = TRUE;
350			}
351			break;
352
353		case AML_LOGICAL_LESS_OP:	/* LLess (Operand0, Operand1) */
354
355			if (integer0 < integer1) {
356				local_result = TRUE;
357			}
358			break;
359
360		default:
361
362			ACPI_ERROR((AE_INFO,
363				    "Invalid comparison opcode: %X", opcode));
364			status = AE_AML_INTERNAL;
365			break;
366		}
367	} else {
368		/*
369		 * 2) Both operands are Strings or both are Buffers
370		 *    Note: Code below takes advantage of common Buffer/String
371		 *          object fields. local_operand1 may have changed above. Use
372		 *          memcmp to handle nulls in buffers.
373		 */
374		length0 = operand0->buffer.length;
375		length1 = local_operand1->buffer.length;
376
377		/* Lexicographic compare: compare the data bytes */
378
379		compare = memcmp(operand0->buffer.pointer,
380				 local_operand1->buffer.pointer,
381				 (length0 > length1) ? length1 : length0);
382
383		switch (opcode) {
384		case AML_LOGICAL_EQUAL_OP:	/* LEqual (Operand0, Operand1) */
385
386			/* Length and all bytes must be equal */
387
388			if ((length0 == length1) && (compare == 0)) {
389
390				/* Length and all bytes match ==> TRUE */
391
392				local_result = TRUE;
393			}
394			break;
395
396		case AML_LOGICAL_GREATER_OP:	/* LGreater (Operand0, Operand1) */
397
398			if (compare > 0) {
399				local_result = TRUE;
400				goto cleanup;	/* TRUE */
401			}
402			if (compare < 0) {
403				goto cleanup;	/* FALSE */
404			}
405
406			/* Bytes match (to shortest length), compare lengths */
407
408			if (length0 > length1) {
409				local_result = TRUE;
410			}
411			break;
412
413		case AML_LOGICAL_LESS_OP:	/* LLess (Operand0, Operand1) */
414
415			if (compare > 0) {
416				goto cleanup;	/* FALSE */
417			}
418			if (compare < 0) {
419				local_result = TRUE;
420				goto cleanup;	/* TRUE */
421			}
422
423			/* Bytes match (to shortest length), compare lengths */
424
425			if (length0 < length1) {
426				local_result = TRUE;
427			}
428			break;
429
430		default:
431
432			ACPI_ERROR((AE_INFO,
433				    "Invalid comparison opcode: %X", opcode));
434			status = AE_AML_INTERNAL;
435			break;
436		}
437	}
438
439cleanup:
440
441	/* New object was created if implicit conversion performed - delete */
442
443	if (local_operand1 != operand1) {
444		acpi_ut_remove_reference(local_operand1);
445	}
446
447	/* Return the logical result and status */
448
449	*logical_result = local_result;
450	return_ACPI_STATUS(status);
451}
452