xref: /openbmc/linux/drivers/acpi/acpica/exutils.c (revision b627b4ed)
1 
2 /******************************************************************************
3  *
4  * Module Name: exutils - interpreter/scanner utilities
5  *
6  *****************************************************************************/
7 
8 /*
9  * Copyright (C) 2000 - 2008, 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.
30  *
31  * NO WARRANTY
32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42  * POSSIBILITY OF SUCH DAMAGES.
43  */
44 
45 /*
46  * DEFINE_AML_GLOBALS is tested in amlcode.h
47  * to determine whether certain global names should be "defined" or only
48  * "declared" in the current compilation.  This enhances maintainability
49  * by enabling a single header file to embody all knowledge of the names
50  * in question.
51  *
52  * Exactly one module of any executable should #define DEFINE_GLOBALS
53  * before #including the header files which use this convention.  The
54  * names in question will be defined and initialized in that module,
55  * and declared as extern in all other modules which #include those
56  * header files.
57  */
58 
59 #define DEFINE_AML_GLOBALS
60 
61 #include <acpi/acpi.h>
62 #include "accommon.h"
63 #include "acinterp.h"
64 #include "amlcode.h"
65 
66 #define _COMPONENT          ACPI_EXECUTER
67 ACPI_MODULE_NAME("exutils")
68 
69 /* Local prototypes */
70 static u32 acpi_ex_digits_needed(acpi_integer value, u32 base);
71 
72 #ifndef ACPI_NO_METHOD_EXECUTION
73 /*******************************************************************************
74  *
75  * FUNCTION:    acpi_ex_enter_interpreter
76  *
77  * PARAMETERS:  None
78  *
79  * RETURN:      None
80  *
81  * DESCRIPTION: Enter the interpreter execution region. Failure to enter
82  *              the interpreter region is a fatal system error. Used in
83  *              conjunction with exit_interpreter.
84  *
85  ******************************************************************************/
86 
87 void acpi_ex_enter_interpreter(void)
88 {
89 	acpi_status status;
90 
91 	ACPI_FUNCTION_TRACE(ex_enter_interpreter);
92 
93 	status = acpi_ut_acquire_mutex(ACPI_MTX_INTERPRETER);
94 	if (ACPI_FAILURE(status)) {
95 		ACPI_ERROR((AE_INFO,
96 			    "Could not acquire AML Interpreter mutex"));
97 	}
98 
99 	return_VOID;
100 }
101 
102 /*******************************************************************************
103  *
104  * FUNCTION:    acpi_ex_reacquire_interpreter
105  *
106  * PARAMETERS:  None
107  *
108  * RETURN:      None
109  *
110  * DESCRIPTION: Reacquire the interpreter execution region from within the
111  *              interpreter code. Failure to enter the interpreter region is a
112  *              fatal system error. Used in  conjuction with
113  *              relinquish_interpreter
114  *
115  ******************************************************************************/
116 
117 void acpi_ex_reacquire_interpreter(void)
118 {
119 	ACPI_FUNCTION_TRACE(ex_reacquire_interpreter);
120 
121 	/*
122 	 * If the global serialized flag is set, do not release the interpreter,
123 	 * since it was not actually released by acpi_ex_relinquish_interpreter.
124 	 * This forces the interpreter to be single threaded.
125 	 */
126 	if (!acpi_gbl_all_methods_serialized) {
127 		acpi_ex_enter_interpreter();
128 	}
129 
130 	return_VOID;
131 }
132 
133 /*******************************************************************************
134  *
135  * FUNCTION:    acpi_ex_exit_interpreter
136  *
137  * PARAMETERS:  None
138  *
139  * RETURN:      None
140  *
141  * DESCRIPTION: Exit the interpreter execution region. This is the top level
142  *              routine used to exit the interpreter when all processing has
143  *              been completed.
144  *
145  ******************************************************************************/
146 
147 void acpi_ex_exit_interpreter(void)
148 {
149 	acpi_status status;
150 
151 	ACPI_FUNCTION_TRACE(ex_exit_interpreter);
152 
153 	status = acpi_ut_release_mutex(ACPI_MTX_INTERPRETER);
154 	if (ACPI_FAILURE(status)) {
155 		ACPI_ERROR((AE_INFO,
156 			    "Could not release AML Interpreter mutex"));
157 	}
158 
159 	return_VOID;
160 }
161 
162 /*******************************************************************************
163  *
164  * FUNCTION:    acpi_ex_relinquish_interpreter
165  *
166  * PARAMETERS:  None
167  *
168  * RETURN:      None
169  *
170  * DESCRIPTION: Exit the interpreter execution region, from within the
171  *              interpreter - before attempting an operation that will possibly
172  *              block the running thread.
173  *
174  * Cases where the interpreter is unlocked internally
175  *      1) Method to be blocked on a Sleep() AML opcode
176  *      2) Method to be blocked on an Acquire() AML opcode
177  *      3) Method to be blocked on a Wait() AML opcode
178  *      4) Method to be blocked to acquire the global lock
179  *      5) Method to be blocked waiting to execute a serialized control method
180  *          that is currently executing
181  *      6) About to invoke a user-installed opregion handler
182  *
183  ******************************************************************************/
184 
185 void acpi_ex_relinquish_interpreter(void)
186 {
187 	ACPI_FUNCTION_TRACE(ex_relinquish_interpreter);
188 
189 	/*
190 	 * If the global serialized flag is set, do not release the interpreter.
191 	 * This forces the interpreter to be single threaded.
192 	 */
193 	if (!acpi_gbl_all_methods_serialized) {
194 		acpi_ex_exit_interpreter();
195 	}
196 
197 	return_VOID;
198 }
199 
200 /*******************************************************************************
201  *
202  * FUNCTION:    acpi_ex_truncate_for32bit_table
203  *
204  * PARAMETERS:  obj_desc        - Object to be truncated
205  *
206  * RETURN:      none
207  *
208  * DESCRIPTION: Truncate an ACPI Integer to 32 bits if the execution mode is
209  *              32-bit, as determined by the revision of the DSDT.
210  *
211  ******************************************************************************/
212 
213 void acpi_ex_truncate_for32bit_table(union acpi_operand_object *obj_desc)
214 {
215 
216 	ACPI_FUNCTION_ENTRY();
217 
218 	/*
219 	 * Object must be a valid number and we must be executing
220 	 * a control method. NS node could be there for AML_INT_NAMEPATH_OP.
221 	 */
222 	if ((!obj_desc) ||
223 	    (ACPI_GET_DESCRIPTOR_TYPE(obj_desc) != ACPI_DESC_TYPE_OPERAND) ||
224 	    (obj_desc->common.type != ACPI_TYPE_INTEGER)) {
225 		return;
226 	}
227 
228 	if (acpi_gbl_integer_byte_width == 4) {
229 		/*
230 		 * We are running a method that exists in a 32-bit ACPI table.
231 		 * Truncate the value to 32 bits by zeroing out the upper 32-bit field
232 		 */
233 		obj_desc->integer.value &= (acpi_integer) ACPI_UINT32_MAX;
234 	}
235 }
236 
237 /*******************************************************************************
238  *
239  * FUNCTION:    acpi_ex_acquire_global_lock
240  *
241  * PARAMETERS:  field_flags           - Flags with Lock rule:
242  *                                      always_lock or never_lock
243  *
244  * RETURN:      None
245  *
246  * DESCRIPTION: Obtain the ACPI hardware Global Lock, only if the field
247  *              flags specifiy that it is to be obtained before field access.
248  *
249  ******************************************************************************/
250 
251 void acpi_ex_acquire_global_lock(u32 field_flags)
252 {
253 	acpi_status status;
254 
255 	ACPI_FUNCTION_TRACE(ex_acquire_global_lock);
256 
257 	/* Only use the lock if the always_lock bit is set */
258 
259 	if (!(field_flags & AML_FIELD_LOCK_RULE_MASK)) {
260 		return_VOID;
261 	}
262 
263 	/* Attempt to get the global lock, wait forever */
264 
265 	status = acpi_ex_acquire_mutex_object(ACPI_WAIT_FOREVER,
266 					      acpi_gbl_global_lock_mutex,
267 					      acpi_os_get_thread_id());
268 
269 	if (ACPI_FAILURE(status)) {
270 		ACPI_EXCEPTION((AE_INFO, status,
271 				"Could not acquire Global Lock"));
272 	}
273 
274 	return_VOID;
275 }
276 
277 /*******************************************************************************
278  *
279  * FUNCTION:    acpi_ex_release_global_lock
280  *
281  * PARAMETERS:  field_flags           - Flags with Lock rule:
282  *                                      always_lock or never_lock
283  *
284  * RETURN:      None
285  *
286  * DESCRIPTION: Release the ACPI hardware Global Lock
287  *
288  ******************************************************************************/
289 
290 void acpi_ex_release_global_lock(u32 field_flags)
291 {
292 	acpi_status status;
293 
294 	ACPI_FUNCTION_TRACE(ex_release_global_lock);
295 
296 	/* Only use the lock if the always_lock bit is set */
297 
298 	if (!(field_flags & AML_FIELD_LOCK_RULE_MASK)) {
299 		return_VOID;
300 	}
301 
302 	/* Release the global lock */
303 
304 	status = acpi_ex_release_mutex_object(acpi_gbl_global_lock_mutex);
305 	if (ACPI_FAILURE(status)) {
306 
307 		/* Report the error, but there isn't much else we can do */
308 
309 		ACPI_EXCEPTION((AE_INFO, status,
310 				"Could not release Global Lock"));
311 	}
312 
313 	return_VOID;
314 }
315 
316 /*******************************************************************************
317  *
318  * FUNCTION:    acpi_ex_digits_needed
319  *
320  * PARAMETERS:  Value           - Value to be represented
321  *              Base            - Base of representation
322  *
323  * RETURN:      The number of digits.
324  *
325  * DESCRIPTION: Calculate the number of digits needed to represent the Value
326  *              in the given Base (Radix)
327  *
328  ******************************************************************************/
329 
330 static u32 acpi_ex_digits_needed(acpi_integer value, u32 base)
331 {
332 	u32 num_digits;
333 	acpi_integer current_value;
334 
335 	ACPI_FUNCTION_TRACE(ex_digits_needed);
336 
337 	/* acpi_integer is unsigned, so we don't worry about a '-' prefix */
338 
339 	if (value == 0) {
340 		return_UINT32(1);
341 	}
342 
343 	current_value = value;
344 	num_digits = 0;
345 
346 	/* Count the digits in the requested base */
347 
348 	while (current_value) {
349 		(void)acpi_ut_short_divide(current_value, base, &current_value,
350 					   NULL);
351 		num_digits++;
352 	}
353 
354 	return_UINT32(num_digits);
355 }
356 
357 /*******************************************************************************
358  *
359  * FUNCTION:    acpi_ex_eisa_id_to_string
360  *
361  * PARAMETERS:  numeric_id      - EISA ID to be converted
362  *              out_string      - Where to put the converted string (8 bytes)
363  *
364  * RETURN:      None
365  *
366  * DESCRIPTION: Convert a numeric EISA ID to string representation
367  *
368  ******************************************************************************/
369 
370 void acpi_ex_eisa_id_to_string(u32 numeric_id, char *out_string)
371 {
372 	u32 eisa_id;
373 
374 	ACPI_FUNCTION_ENTRY();
375 
376 	/* Swap ID to big-endian to get contiguous bits */
377 
378 	eisa_id = acpi_ut_dword_byte_swap(numeric_id);
379 
380 	out_string[0] = (char)('@' + (((unsigned long)eisa_id >> 26) & 0x1f));
381 	out_string[1] = (char)('@' + ((eisa_id >> 21) & 0x1f));
382 	out_string[2] = (char)('@' + ((eisa_id >> 16) & 0x1f));
383 	out_string[3] = acpi_ut_hex_to_ascii_char((acpi_integer) eisa_id, 12);
384 	out_string[4] = acpi_ut_hex_to_ascii_char((acpi_integer) eisa_id, 8);
385 	out_string[5] = acpi_ut_hex_to_ascii_char((acpi_integer) eisa_id, 4);
386 	out_string[6] = acpi_ut_hex_to_ascii_char((acpi_integer) eisa_id, 0);
387 	out_string[7] = 0;
388 }
389 
390 /*******************************************************************************
391  *
392  * FUNCTION:    acpi_ex_unsigned_integer_to_string
393  *
394  * PARAMETERS:  Value           - Value to be converted
395  *              out_string      - Where to put the converted string (8 bytes)
396  *
397  * RETURN:      None, string
398  *
399  * DESCRIPTION: Convert a number to string representation. Assumes string
400  *              buffer is large enough to hold the string.
401  *
402  ******************************************************************************/
403 
404 void acpi_ex_unsigned_integer_to_string(acpi_integer value, char *out_string)
405 {
406 	u32 count;
407 	u32 digits_needed;
408 	u32 remainder;
409 
410 	ACPI_FUNCTION_ENTRY();
411 
412 	digits_needed = acpi_ex_digits_needed(value, 10);
413 	out_string[digits_needed] = 0;
414 
415 	for (count = digits_needed; count > 0; count--) {
416 		(void)acpi_ut_short_divide(value, 10, &value, &remainder);
417 		out_string[count - 1] = (char)('0' + remainder);
418 	}
419 }
420 
421 #endif
422