xref: /openbmc/linux/drivers/acpi/acpica/exutils.c (revision 4f3db074)
1 /******************************************************************************
2  *
3  * Module Name: exutils - interpreter/scanner utilities
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2015, 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_exit_interpreter
104  *
105  * PARAMETERS:  None
106  *
107  * RETURN:      None
108  *
109  * DESCRIPTION: Exit the interpreter execution region. This is the top level
110  *              routine used to exit the interpreter when all processing has
111  *              been completed, or when the method blocks.
112  *
113  * Cases where the interpreter is unlocked internally:
114  *      1) Method will be blocked on a Sleep() AML opcode
115  *      2) Method will be blocked on an Acquire() AML opcode
116  *      3) Method will be blocked on a Wait() AML opcode
117  *      4) Method will be blocked to acquire the global lock
118  *      5) Method will be blocked waiting to execute a serialized control
119  *          method that is currently executing
120  *      6) About to invoke a user-installed opregion handler
121  *
122  ******************************************************************************/
123 
124 void acpi_ex_exit_interpreter(void)
125 {
126 	acpi_status status;
127 
128 	ACPI_FUNCTION_TRACE(ex_exit_interpreter);
129 
130 	status = acpi_ut_release_mutex(ACPI_MTX_INTERPRETER);
131 	if (ACPI_FAILURE(status)) {
132 		ACPI_ERROR((AE_INFO,
133 			    "Could not release AML Interpreter mutex"));
134 	}
135 
136 	return_VOID;
137 }
138 
139 /*******************************************************************************
140  *
141  * FUNCTION:    acpi_ex_truncate_for32bit_table
142  *
143  * PARAMETERS:  obj_desc        - Object to be truncated
144  *
145  * RETURN:      TRUE if a truncation was performed, FALSE otherwise.
146  *
147  * DESCRIPTION: Truncate an ACPI Integer to 32 bits if the execution mode is
148  *              32-bit, as determined by the revision of the DSDT.
149  *
150  ******************************************************************************/
151 
152 u8 acpi_ex_truncate_for32bit_table(union acpi_operand_object *obj_desc)
153 {
154 
155 	ACPI_FUNCTION_ENTRY();
156 
157 	/*
158 	 * Object must be a valid number and we must be executing
159 	 * a control method. Object could be NS node for AML_INT_NAMEPATH_OP.
160 	 */
161 	if ((!obj_desc) ||
162 	    (ACPI_GET_DESCRIPTOR_TYPE(obj_desc) != ACPI_DESC_TYPE_OPERAND) ||
163 	    (obj_desc->common.type != ACPI_TYPE_INTEGER)) {
164 		return (FALSE);
165 	}
166 
167 	if ((acpi_gbl_integer_byte_width == 4) &&
168 	    (obj_desc->integer.value > (u64)ACPI_UINT32_MAX)) {
169 		/*
170 		 * We are executing in a 32-bit ACPI table.
171 		 * Truncate the value to 32 bits by zeroing out the upper 32-bit field
172 		 */
173 		obj_desc->integer.value &= (u64)ACPI_UINT32_MAX;
174 		return (TRUE);
175 	}
176 
177 	return (FALSE);
178 }
179 
180 /*******************************************************************************
181  *
182  * FUNCTION:    acpi_ex_acquire_global_lock
183  *
184  * PARAMETERS:  field_flags           - Flags with Lock rule:
185  *                                      always_lock or never_lock
186  *
187  * RETURN:      None
188  *
189  * DESCRIPTION: Obtain the ACPI hardware Global Lock, only if the field
190  *              flags specifiy that it is to be obtained before field access.
191  *
192  ******************************************************************************/
193 
194 void acpi_ex_acquire_global_lock(u32 field_flags)
195 {
196 	acpi_status status;
197 
198 	ACPI_FUNCTION_TRACE(ex_acquire_global_lock);
199 
200 	/* Only use the lock if the always_lock bit is set */
201 
202 	if (!(field_flags & AML_FIELD_LOCK_RULE_MASK)) {
203 		return_VOID;
204 	}
205 
206 	/* Attempt to get the global lock, wait forever */
207 
208 	status = acpi_ex_acquire_mutex_object(ACPI_WAIT_FOREVER,
209 					      acpi_gbl_global_lock_mutex,
210 					      acpi_os_get_thread_id());
211 
212 	if (ACPI_FAILURE(status)) {
213 		ACPI_EXCEPTION((AE_INFO, status,
214 				"Could not acquire Global Lock"));
215 	}
216 
217 	return_VOID;
218 }
219 
220 /*******************************************************************************
221  *
222  * FUNCTION:    acpi_ex_release_global_lock
223  *
224  * PARAMETERS:  field_flags           - Flags with Lock rule:
225  *                                      always_lock or never_lock
226  *
227  * RETURN:      None
228  *
229  * DESCRIPTION: Release the ACPI hardware Global Lock
230  *
231  ******************************************************************************/
232 
233 void acpi_ex_release_global_lock(u32 field_flags)
234 {
235 	acpi_status status;
236 
237 	ACPI_FUNCTION_TRACE(ex_release_global_lock);
238 
239 	/* Only use the lock if the always_lock bit is set */
240 
241 	if (!(field_flags & AML_FIELD_LOCK_RULE_MASK)) {
242 		return_VOID;
243 	}
244 
245 	/* Release the global lock */
246 
247 	status = acpi_ex_release_mutex_object(acpi_gbl_global_lock_mutex);
248 	if (ACPI_FAILURE(status)) {
249 
250 		/* Report the error, but there isn't much else we can do */
251 
252 		ACPI_EXCEPTION((AE_INFO, status,
253 				"Could not release Global Lock"));
254 	}
255 
256 	return_VOID;
257 }
258 
259 /*******************************************************************************
260  *
261  * FUNCTION:    acpi_ex_digits_needed
262  *
263  * PARAMETERS:  value           - Value to be represented
264  *              base            - Base of representation
265  *
266  * RETURN:      The number of digits.
267  *
268  * DESCRIPTION: Calculate the number of digits needed to represent the Value
269  *              in the given Base (Radix)
270  *
271  ******************************************************************************/
272 
273 static u32 acpi_ex_digits_needed(u64 value, u32 base)
274 {
275 	u32 num_digits;
276 	u64 current_value;
277 
278 	ACPI_FUNCTION_TRACE(ex_digits_needed);
279 
280 	/* u64 is unsigned, so we don't worry about a '-' prefix */
281 
282 	if (value == 0) {
283 		return_UINT32(1);
284 	}
285 
286 	current_value = value;
287 	num_digits = 0;
288 
289 	/* Count the digits in the requested base */
290 
291 	while (current_value) {
292 		(void)acpi_ut_short_divide(current_value, base, &current_value,
293 					   NULL);
294 		num_digits++;
295 	}
296 
297 	return_UINT32(num_digits);
298 }
299 
300 /*******************************************************************************
301  *
302  * FUNCTION:    acpi_ex_eisa_id_to_string
303  *
304  * PARAMETERS:  compressed_id   - EISAID to be converted
305  *              out_string      - Where to put the converted string (8 bytes)
306  *
307  * RETURN:      None
308  *
309  * DESCRIPTION: Convert a numeric EISAID to string representation. Return
310  *              buffer must be large enough to hold the string. The string
311  *              returned is always exactly of length ACPI_EISAID_STRING_SIZE
312  *              (includes null terminator). The EISAID is always 32 bits.
313  *
314  ******************************************************************************/
315 
316 void acpi_ex_eisa_id_to_string(char *out_string, u64 compressed_id)
317 {
318 	u32 swapped_id;
319 
320 	ACPI_FUNCTION_ENTRY();
321 
322 	/* The EISAID should be a 32-bit integer */
323 
324 	if (compressed_id > ACPI_UINT32_MAX) {
325 		ACPI_WARNING((AE_INFO,
326 			      "Expected EISAID is larger than 32 bits: 0x%8.8X%8.8X, truncating",
327 			      ACPI_FORMAT_UINT64(compressed_id)));
328 	}
329 
330 	/* Swap ID to big-endian to get contiguous bits */
331 
332 	swapped_id = acpi_ut_dword_byte_swap((u32)compressed_id);
333 
334 	/* First 3 bytes are uppercase letters. Next 4 bytes are hexadecimal */
335 
336 	out_string[0] =
337 	    (char)(0x40 + (((unsigned long)swapped_id >> 26) & 0x1F));
338 	out_string[1] = (char)(0x40 + ((swapped_id >> 21) & 0x1F));
339 	out_string[2] = (char)(0x40 + ((swapped_id >> 16) & 0x1F));
340 	out_string[3] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 12);
341 	out_string[4] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 8);
342 	out_string[5] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 4);
343 	out_string[6] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 0);
344 	out_string[7] = 0;
345 }
346 
347 /*******************************************************************************
348  *
349  * FUNCTION:    acpi_ex_integer_to_string
350  *
351  * PARAMETERS:  out_string      - Where to put the converted string. At least
352  *                                21 bytes are needed to hold the largest
353  *                                possible 64-bit integer.
354  *              value           - Value to be converted
355  *
356  * RETURN:      None, string
357  *
358  * DESCRIPTION: Convert a 64-bit integer to decimal string representation.
359  *              Assumes string buffer is large enough to hold the string. The
360  *              largest string is (ACPI_MAX64_DECIMAL_DIGITS + 1).
361  *
362  ******************************************************************************/
363 
364 void acpi_ex_integer_to_string(char *out_string, u64 value)
365 {
366 	u32 count;
367 	u32 digits_needed;
368 	u32 remainder;
369 
370 	ACPI_FUNCTION_ENTRY();
371 
372 	digits_needed = acpi_ex_digits_needed(value, 10);
373 	out_string[digits_needed] = 0;
374 
375 	for (count = digits_needed; count > 0; count--) {
376 		(void)acpi_ut_short_divide(value, 10, &value, &remainder);
377 		out_string[count - 1] = (char)('0' + remainder);
378 	}
379 }
380 
381 /*******************************************************************************
382  *
383  * FUNCTION:    acpi_is_valid_space_id
384  *
385  * PARAMETERS:  space_id            - ID to be validated
386  *
387  * RETURN:      TRUE if valid/supported ID.
388  *
389  * DESCRIPTION: Validate an operation region space_ID.
390  *
391  ******************************************************************************/
392 
393 u8 acpi_is_valid_space_id(u8 space_id)
394 {
395 
396 	if ((space_id >= ACPI_NUM_PREDEFINED_REGIONS) &&
397 	    (space_id < ACPI_USER_REGION_BEGIN) &&
398 	    (space_id != ACPI_ADR_SPACE_DATA_TABLE) &&
399 	    (space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) {
400 		return (FALSE);
401 	}
402 
403 	return (TRUE);
404 }
405 
406 #endif
407