xref: /openbmc/linux/drivers/acpi/acpica/exutils.c (revision e23feb16)
1 /******************************************************************************
2  *
3  * Module Name: exutils - interpreter/scanner utilities
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2013, 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 /*
45  * DEFINE_AML_GLOBALS is tested in amlcode.h
46  * to determine whether certain global names should be "defined" or only
47  * "declared" in the current compilation. This enhances maintainability
48  * by enabling a single header file to embody all knowledge of the names
49  * in question.
50  *
51  * Exactly one module of any executable should #define DEFINE_GLOBALS
52  * before #including the header files which use this convention. The
53  * names in question will be defined and initialized in that module,
54  * and declared as extern in all other modules which #include those
55  * header files.
56  */
57 
58 #define DEFINE_AML_GLOBALS
59 
60 #include <acpi/acpi.h>
61 #include "accommon.h"
62 #include "acinterp.h"
63 #include "amlcode.h"
64 
65 #define _COMPONENT          ACPI_EXECUTER
66 ACPI_MODULE_NAME("exutils")
67 
68 /* Local prototypes */
69 static u32 acpi_ex_digits_needed(u64 value, u32 base);
70 
71 #ifndef ACPI_NO_METHOD_EXECUTION
72 /*******************************************************************************
73  *
74  * FUNCTION:    acpi_ex_enter_interpreter
75  *
76  * PARAMETERS:  None
77  *
78  * RETURN:      None
79  *
80  * DESCRIPTION: Enter the interpreter execution region. Failure to enter
81  *              the interpreter region is a fatal system error. Used in
82  *              conjunction with exit_interpreter.
83  *
84  ******************************************************************************/
85 
86 void acpi_ex_enter_interpreter(void)
87 {
88 	acpi_status status;
89 
90 	ACPI_FUNCTION_TRACE(ex_enter_interpreter);
91 
92 	status = acpi_ut_acquire_mutex(ACPI_MTX_INTERPRETER);
93 	if (ACPI_FAILURE(status)) {
94 		ACPI_ERROR((AE_INFO,
95 			    "Could not acquire AML Interpreter mutex"));
96 	}
97 
98 	return_VOID;
99 }
100 
101 /*******************************************************************************
102  *
103  * FUNCTION:    acpi_ex_reacquire_interpreter
104  *
105  * PARAMETERS:  None
106  *
107  * RETURN:      None
108  *
109  * DESCRIPTION: Reacquire the interpreter execution region from within the
110  *              interpreter code. Failure to enter the interpreter region is a
111  *              fatal system error. Used in conjunction with
112  *              relinquish_interpreter
113  *
114  ******************************************************************************/
115 
116 void acpi_ex_reacquire_interpreter(void)
117 {
118 	ACPI_FUNCTION_TRACE(ex_reacquire_interpreter);
119 
120 	/*
121 	 * If the global serialized flag is set, do not release the interpreter,
122 	 * since it was not actually released by acpi_ex_relinquish_interpreter.
123 	 * This forces the interpreter to be single threaded.
124 	 */
125 	if (!acpi_gbl_all_methods_serialized) {
126 		acpi_ex_enter_interpreter();
127 	}
128 
129 	return_VOID;
130 }
131 
132 /*******************************************************************************
133  *
134  * FUNCTION:    acpi_ex_exit_interpreter
135  *
136  * PARAMETERS:  None
137  *
138  * RETURN:      None
139  *
140  * DESCRIPTION: Exit the interpreter execution region. This is the top level
141  *              routine used to exit the interpreter when all processing has
142  *              been completed.
143  *
144  ******************************************************************************/
145 
146 void acpi_ex_exit_interpreter(void)
147 {
148 	acpi_status status;
149 
150 	ACPI_FUNCTION_TRACE(ex_exit_interpreter);
151 
152 	status = acpi_ut_release_mutex(ACPI_MTX_INTERPRETER);
153 	if (ACPI_FAILURE(status)) {
154 		ACPI_ERROR((AE_INFO,
155 			    "Could not release AML Interpreter mutex"));
156 	}
157 
158 	return_VOID;
159 }
160 
161 /*******************************************************************************
162  *
163  * FUNCTION:    acpi_ex_relinquish_interpreter
164  *
165  * PARAMETERS:  None
166  *
167  * RETURN:      None
168  *
169  * DESCRIPTION: Exit the interpreter execution region, from within the
170  *              interpreter - before attempting an operation that will possibly
171  *              block the running thread.
172  *
173  * Cases where the interpreter is unlocked internally
174  *      1) Method to be blocked on a Sleep() AML opcode
175  *      2) Method to be blocked on an Acquire() AML opcode
176  *      3) Method to be blocked on a Wait() AML opcode
177  *      4) Method to be blocked to acquire the global lock
178  *      5) Method to be blocked waiting to execute a serialized control method
179  *          that is currently executing
180  *      6) About to invoke a user-installed opregion handler
181  *
182  ******************************************************************************/
183 
184 void acpi_ex_relinquish_interpreter(void)
185 {
186 	ACPI_FUNCTION_TRACE(ex_relinquish_interpreter);
187 
188 	/*
189 	 * If the global serialized flag is set, do not release the interpreter.
190 	 * This forces the interpreter to be single threaded.
191 	 */
192 	if (!acpi_gbl_all_methods_serialized) {
193 		acpi_ex_exit_interpreter();
194 	}
195 
196 	return_VOID;
197 }
198 
199 /*******************************************************************************
200  *
201  * FUNCTION:    acpi_ex_truncate_for32bit_table
202  *
203  * PARAMETERS:  obj_desc        - Object to be truncated
204  *
205  * RETURN:      TRUE if a truncation was performed, FALSE otherwise.
206  *
207  * DESCRIPTION: Truncate an ACPI Integer to 32 bits if the execution mode is
208  *              32-bit, as determined by the revision of the DSDT.
209  *
210  ******************************************************************************/
211 
212 u8 acpi_ex_truncate_for32bit_table(union acpi_operand_object *obj_desc)
213 {
214 
215 	ACPI_FUNCTION_ENTRY();
216 
217 	/*
218 	 * Object must be a valid number and we must be executing
219 	 * a control method. Object could be NS node for AML_INT_NAMEPATH_OP.
220 	 */
221 	if ((!obj_desc) ||
222 	    (ACPI_GET_DESCRIPTOR_TYPE(obj_desc) != ACPI_DESC_TYPE_OPERAND) ||
223 	    (obj_desc->common.type != ACPI_TYPE_INTEGER)) {
224 		return (FALSE);
225 	}
226 
227 	if ((acpi_gbl_integer_byte_width == 4) &&
228 	    (obj_desc->integer.value > (u64)ACPI_UINT32_MAX)) {
229 		/*
230 		 * We are executing 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 &= (u64)ACPI_UINT32_MAX;
234 		return (TRUE);
235 	}
236 
237 	return (FALSE);
238 }
239 
240 /*******************************************************************************
241  *
242  * FUNCTION:    acpi_ex_acquire_global_lock
243  *
244  * PARAMETERS:  field_flags           - Flags with Lock rule:
245  *                                      always_lock or never_lock
246  *
247  * RETURN:      None
248  *
249  * DESCRIPTION: Obtain the ACPI hardware Global Lock, only if the field
250  *              flags specifiy that it is to be obtained before field access.
251  *
252  ******************************************************************************/
253 
254 void acpi_ex_acquire_global_lock(u32 field_flags)
255 {
256 	acpi_status status;
257 
258 	ACPI_FUNCTION_TRACE(ex_acquire_global_lock);
259 
260 	/* Only use the lock if the always_lock bit is set */
261 
262 	if (!(field_flags & AML_FIELD_LOCK_RULE_MASK)) {
263 		return_VOID;
264 	}
265 
266 	/* Attempt to get the global lock, wait forever */
267 
268 	status = acpi_ex_acquire_mutex_object(ACPI_WAIT_FOREVER,
269 					      acpi_gbl_global_lock_mutex,
270 					      acpi_os_get_thread_id());
271 
272 	if (ACPI_FAILURE(status)) {
273 		ACPI_EXCEPTION((AE_INFO, status,
274 				"Could not acquire Global Lock"));
275 	}
276 
277 	return_VOID;
278 }
279 
280 /*******************************************************************************
281  *
282  * FUNCTION:    acpi_ex_release_global_lock
283  *
284  * PARAMETERS:  field_flags           - Flags with Lock rule:
285  *                                      always_lock or never_lock
286  *
287  * RETURN:      None
288  *
289  * DESCRIPTION: Release the ACPI hardware Global Lock
290  *
291  ******************************************************************************/
292 
293 void acpi_ex_release_global_lock(u32 field_flags)
294 {
295 	acpi_status status;
296 
297 	ACPI_FUNCTION_TRACE(ex_release_global_lock);
298 
299 	/* Only use the lock if the always_lock bit is set */
300 
301 	if (!(field_flags & AML_FIELD_LOCK_RULE_MASK)) {
302 		return_VOID;
303 	}
304 
305 	/* Release the global lock */
306 
307 	status = acpi_ex_release_mutex_object(acpi_gbl_global_lock_mutex);
308 	if (ACPI_FAILURE(status)) {
309 
310 		/* Report the error, but there isn't much else we can do */
311 
312 		ACPI_EXCEPTION((AE_INFO, status,
313 				"Could not release Global Lock"));
314 	}
315 
316 	return_VOID;
317 }
318 
319 /*******************************************************************************
320  *
321  * FUNCTION:    acpi_ex_digits_needed
322  *
323  * PARAMETERS:  value           - Value to be represented
324  *              base            - Base of representation
325  *
326  * RETURN:      The number of digits.
327  *
328  * DESCRIPTION: Calculate the number of digits needed to represent the Value
329  *              in the given Base (Radix)
330  *
331  ******************************************************************************/
332 
333 static u32 acpi_ex_digits_needed(u64 value, u32 base)
334 {
335 	u32 num_digits;
336 	u64 current_value;
337 
338 	ACPI_FUNCTION_TRACE(ex_digits_needed);
339 
340 	/* u64 is unsigned, so we don't worry about a '-' prefix */
341 
342 	if (value == 0) {
343 		return_UINT32(1);
344 	}
345 
346 	current_value = value;
347 	num_digits = 0;
348 
349 	/* Count the digits in the requested base */
350 
351 	while (current_value) {
352 		(void)acpi_ut_short_divide(current_value, base, &current_value,
353 					   NULL);
354 		num_digits++;
355 	}
356 
357 	return_UINT32(num_digits);
358 }
359 
360 /*******************************************************************************
361  *
362  * FUNCTION:    acpi_ex_eisa_id_to_string
363  *
364  * PARAMETERS:  compressed_id   - EISAID to be converted
365  *              out_string      - Where to put the converted string (8 bytes)
366  *
367  * RETURN:      None
368  *
369  * DESCRIPTION: Convert a numeric EISAID to string representation. Return
370  *              buffer must be large enough to hold the string. The string
371  *              returned is always exactly of length ACPI_EISAID_STRING_SIZE
372  *              (includes null terminator). The EISAID is always 32 bits.
373  *
374  ******************************************************************************/
375 
376 void acpi_ex_eisa_id_to_string(char *out_string, u64 compressed_id)
377 {
378 	u32 swapped_id;
379 
380 	ACPI_FUNCTION_ENTRY();
381 
382 	/* The EISAID should be a 32-bit integer */
383 
384 	if (compressed_id > ACPI_UINT32_MAX) {
385 		ACPI_WARNING((AE_INFO,
386 			      "Expected EISAID is larger than 32 bits: 0x%8.8X%8.8X, truncating",
387 			      ACPI_FORMAT_UINT64(compressed_id)));
388 	}
389 
390 	/* Swap ID to big-endian to get contiguous bits */
391 
392 	swapped_id = acpi_ut_dword_byte_swap((u32)compressed_id);
393 
394 	/* First 3 bytes are uppercase letters. Next 4 bytes are hexadecimal */
395 
396 	out_string[0] =
397 	    (char)(0x40 + (((unsigned long)swapped_id >> 26) & 0x1F));
398 	out_string[1] = (char)(0x40 + ((swapped_id >> 21) & 0x1F));
399 	out_string[2] = (char)(0x40 + ((swapped_id >> 16) & 0x1F));
400 	out_string[3] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 12);
401 	out_string[4] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 8);
402 	out_string[5] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 4);
403 	out_string[6] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 0);
404 	out_string[7] = 0;
405 }
406 
407 /*******************************************************************************
408  *
409  * FUNCTION:    acpi_ex_integer_to_string
410  *
411  * PARAMETERS:  out_string      - Where to put the converted string. At least
412  *                                21 bytes are needed to hold the largest
413  *                                possible 64-bit integer.
414  *              value           - Value to be converted
415  *
416  * RETURN:      None, string
417  *
418  * DESCRIPTION: Convert a 64-bit integer to decimal string representation.
419  *              Assumes string buffer is large enough to hold the string. The
420  *              largest string is (ACPI_MAX64_DECIMAL_DIGITS + 1).
421  *
422  ******************************************************************************/
423 
424 void acpi_ex_integer_to_string(char *out_string, u64 value)
425 {
426 	u32 count;
427 	u32 digits_needed;
428 	u32 remainder;
429 
430 	ACPI_FUNCTION_ENTRY();
431 
432 	digits_needed = acpi_ex_digits_needed(value, 10);
433 	out_string[digits_needed] = 0;
434 
435 	for (count = digits_needed; count > 0; count--) {
436 		(void)acpi_ut_short_divide(value, 10, &value, &remainder);
437 		out_string[count - 1] = (char)('0' + remainder);
438 	}
439 }
440 
441 /*******************************************************************************
442  *
443  * FUNCTION:    acpi_is_valid_space_id
444  *
445  * PARAMETERS:  space_id            - ID to be validated
446  *
447  * RETURN:      TRUE if valid/supported ID.
448  *
449  * DESCRIPTION: Validate an operation region space_ID.
450  *
451  ******************************************************************************/
452 
453 u8 acpi_is_valid_space_id(u8 space_id)
454 {
455 
456 	if ((space_id >= ACPI_NUM_PREDEFINED_REGIONS) &&
457 	    (space_id < ACPI_USER_REGION_BEGIN) &&
458 	    (space_id != ACPI_ADR_SPACE_DATA_TABLE) &&
459 	    (space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) {
460 		return (FALSE);
461 	}
462 
463 	return (TRUE);
464 }
465 
466 #endif
467