1 /******************************************************************************
2  *
3  * Module Name: exfldio - Aml Field I/O
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2004, R. Byron Moore
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 #include <acpi/acpi.h>
46 #include <acpi/acinterp.h>
47 #include <acpi/amlcode.h>
48 #include <acpi/acevents.h>
49 #include <acpi/acdispat.h>
50 
51 
52 #define _COMPONENT          ACPI_EXECUTER
53 	 ACPI_MODULE_NAME    ("exfldio")
54 
55 
56 /*******************************************************************************
57  *
58  * FUNCTION:    acpi_ex_setup_region
59  *
60  * PARAMETERS:  *obj_desc               - Field to be read or written
61  *              field_datum_byte_offset - Byte offset of this datum within the
62  *                                        parent field
63  *
64  * RETURN:      Status
65  *
66  * DESCRIPTION: Common processing for acpi_ex_extract_from_field and
67  *              acpi_ex_insert_into_field. Initialize the Region if necessary and
68  *              validate the request.
69  *
70  ******************************************************************************/
71 
72 acpi_status
acpi_ex_setup_region(union acpi_operand_object * obj_desc,u32 field_datum_byte_offset)73 acpi_ex_setup_region (
74 	union acpi_operand_object       *obj_desc,
75 	u32                             field_datum_byte_offset)
76 {
77 	acpi_status                     status = AE_OK;
78 	union acpi_operand_object       *rgn_desc;
79 
80 
81 	ACPI_FUNCTION_TRACE_U32 ("ex_setup_region", field_datum_byte_offset);
82 
83 
84 	rgn_desc = obj_desc->common_field.region_obj;
85 
86 	/* We must have a valid region */
87 
88 	if (ACPI_GET_OBJECT_TYPE (rgn_desc) != ACPI_TYPE_REGION) {
89 		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Needed Region, found type %X (%s)\n",
90 			ACPI_GET_OBJECT_TYPE (rgn_desc),
91 			acpi_ut_get_object_type_name (rgn_desc)));
92 
93 		return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
94 	}
95 
96 	/*
97 	 * If the Region Address and Length have not been previously evaluated,
98 	 * evaluate them now and save the results.
99 	 */
100 	if (!(rgn_desc->common.flags & AOPOBJ_DATA_VALID)) {
101 		status = acpi_ds_get_region_arguments (rgn_desc);
102 		if (ACPI_FAILURE (status)) {
103 			return_ACPI_STATUS (status);
104 		}
105 	}
106 
107 	if (rgn_desc->region.space_id == ACPI_ADR_SPACE_SMBUS) {
108 		/* SMBus has a non-linear address space */
109 
110 		return_ACPI_STATUS (AE_OK);
111 	}
112 
113 #ifdef ACPI_UNDER_DEVELOPMENT
114 	/*
115 	 * If the Field access is any_acc, we can now compute the optimal
116 	 * access (because we know know the length of the parent region)
117 	 */
118 	if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
119 		if (ACPI_FAILURE (status)) {
120 			return_ACPI_STATUS (status);
121 		}
122 	}
123 #endif
124 
125 	/*
126 	 * Validate the request.  The entire request from the byte offset for a
127 	 * length of one field datum (access width) must fit within the region.
128 	 * (Region length is specified in bytes)
129 	 */
130 	if (rgn_desc->region.length < (obj_desc->common_field.base_byte_offset
131 			   + field_datum_byte_offset
132 			   + obj_desc->common_field.access_byte_width)) {
133 		if (rgn_desc->region.length < obj_desc->common_field.access_byte_width) {
134 			/*
135 			 * This is the case where the access_type (acc_word, etc.) is wider
136 			 * than the region itself.  For example, a region of length one
137 			 * byte, and a field with Dword access specified.
138 			 */
139 			ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
140 				"Field [%4.4s] access width (%d bytes) too large for region [%4.4s] (length %X)\n",
141 				acpi_ut_get_node_name (obj_desc->common_field.node),
142 				obj_desc->common_field.access_byte_width,
143 				acpi_ut_get_node_name (rgn_desc->region.node), rgn_desc->region.length));
144 		}
145 
146 		/*
147 		 * Offset rounded up to next multiple of field width
148 		 * exceeds region length, indicate an error
149 		 */
150 		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
151 			"Field [%4.4s] Base+Offset+Width %X+%X+%X is beyond end of region [%4.4s] (length %X)\n",
152 			acpi_ut_get_node_name (obj_desc->common_field.node),
153 			obj_desc->common_field.base_byte_offset,
154 			field_datum_byte_offset, obj_desc->common_field.access_byte_width,
155 			acpi_ut_get_node_name (rgn_desc->region.node), rgn_desc->region.length));
156 
157 		if (!acpi_strict) {
158 			/*
159 			 * Allow access to the field if it is within the region size
160 			 * rounded up to a multiple of the access byte width.  This
161 			 * overcomes "off-by-one" programming errors in the AML often
162 			 * found in Toshiba laptops.  These errors were allowed by
163 			 * the Microsoft ASL compiler.
164 			 */
165 			u32 rounded_length = ACPI_ROUND_UP(rgn_desc->region.length,
166 									obj_desc->common_field.access_byte_width);
167 
168 			if (rounded_length < (obj_desc->common_field.base_byte_offset
169 						+ field_datum_byte_offset
170 						+ obj_desc->common_field.access_byte_width)) {
171 				return_ACPI_STATUS (AE_AML_REGION_LIMIT);
172 			} else {
173 				static int	warn_once = 1;
174 				if (warn_once) {
175 					// Could also associate a flag with each field, and
176 					// warn once for each field.
177 					ACPI_REPORT_WARNING((
178 						"The ACPI AML in your computer contains errors, "
179 						"please nag the manufacturer to correct it.\n"));
180 					ACPI_REPORT_WARNING((
181 						"Allowing relaxed access to fields; "
182 						"turn on CONFIG_ACPI_DEBUG for details.\n"));
183 					warn_once = 0;
184 				}
185 				return_ACPI_STATUS (AE_OK);
186 			}
187 		}
188 		else {
189 			return_ACPI_STATUS (AE_AML_REGION_LIMIT);
190 		}
191 	}
192 
193 	return_ACPI_STATUS (AE_OK);
194 }
195 
196 
197 /*******************************************************************************
198  *
199  * FUNCTION:    acpi_ex_access_region
200  *
201  * PARAMETERS:  *obj_desc               - Field to be read
202  *              field_datum_byte_offset - Byte offset of this datum within the
203  *                                        parent field
204  *              *Value                  - Where to store value (must at least
205  *                                        the size of acpi_integer)
206  *              Function                - Read or Write flag plus other region-
207  *                                        dependent flags
208  *
209  * RETURN:      Status
210  *
211  * DESCRIPTION: Read or Write a single field datum to an Operation Region.
212  *
213  ******************************************************************************/
214 
215 acpi_status
acpi_ex_access_region(union acpi_operand_object * obj_desc,u32 field_datum_byte_offset,acpi_integer * value,u32 function)216 acpi_ex_access_region (
217 	union acpi_operand_object       *obj_desc,
218 	u32                             field_datum_byte_offset,
219 	acpi_integer                    *value,
220 	u32                             function)
221 {
222 	acpi_status                     status;
223 	union acpi_operand_object       *rgn_desc;
224 	acpi_physical_address           address;
225 
226 
227 	ACPI_FUNCTION_TRACE ("ex_access_region");
228 
229 
230 	/*
231 	 * Ensure that the region operands are fully evaluated and verify
232 	 * the validity of the request
233 	 */
234 	status = acpi_ex_setup_region (obj_desc, field_datum_byte_offset);
235 	if (ACPI_FAILURE (status)) {
236 		return_ACPI_STATUS (status);
237 	}
238 
239 	/*
240 	 * The physical address of this field datum is:
241 	 *
242 	 * 1) The base of the region, plus
243 	 * 2) The base offset of the field, plus
244 	 * 3) The current offset into the field
245 	 */
246 	rgn_desc = obj_desc->common_field.region_obj;
247 	address = rgn_desc->region.address
248 			 + obj_desc->common_field.base_byte_offset
249 			 + field_datum_byte_offset;
250 
251 	if ((function & ACPI_IO_MASK) == ACPI_READ) {
252 		ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "[READ]"));
253 	}
254 	else {
255 		ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "[WRITE]"));
256 	}
257 
258 	ACPI_DEBUG_PRINT_RAW ((ACPI_DB_BFIELD,
259 		" Region [%s:%X], Width %X, byte_base %X, Offset %X at %8.8X%8.8X\n",
260 		acpi_ut_get_region_name (rgn_desc->region.space_id),
261 		rgn_desc->region.space_id,
262 		obj_desc->common_field.access_byte_width,
263 		obj_desc->common_field.base_byte_offset,
264 		field_datum_byte_offset,
265 		ACPI_FORMAT_UINT64 (address)));
266 
267 	/* Invoke the appropriate address_space/op_region handler */
268 
269 	status = acpi_ev_address_space_dispatch (rgn_desc, function,
270 			  address, ACPI_MUL_8 (obj_desc->common_field.access_byte_width), value);
271 
272 	if (ACPI_FAILURE (status)) {
273 		if (status == AE_NOT_IMPLEMENTED) {
274 			ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
275 				"Region %s(%X) not implemented\n",
276 				acpi_ut_get_region_name (rgn_desc->region.space_id),
277 				rgn_desc->region.space_id));
278 		}
279 		else if (status == AE_NOT_EXIST) {
280 			ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
281 				"Region %s(%X) has no handler\n",
282 				acpi_ut_get_region_name (rgn_desc->region.space_id),
283 				rgn_desc->region.space_id));
284 		}
285 	}
286 
287 	return_ACPI_STATUS (status);
288 }
289 
290 
291 /*******************************************************************************
292  *
293  * FUNCTION:    acpi_ex_register_overflow
294  *
295  * PARAMETERS:  *obj_desc               - Register(Field) to be written
296  *              Value                   - Value to be stored
297  *
298  * RETURN:      TRUE if value overflows the field, FALSE otherwise
299  *
300  * DESCRIPTION: Check if a value is out of range of the field being written.
301  *              Used to check if the values written to Index and Bank registers
302  *              are out of range.  Normally, the value is simply truncated
303  *              to fit the field, but this case is most likely a serious
304  *              coding error in the ASL.
305  *
306  ******************************************************************************/
307 
308 u8
acpi_ex_register_overflow(union acpi_operand_object * obj_desc,acpi_integer value)309 acpi_ex_register_overflow (
310 	union acpi_operand_object       *obj_desc,
311 	acpi_integer                    value)
312 {
313 
314 	if (obj_desc->common_field.bit_length >= ACPI_INTEGER_BIT_SIZE) {
315 		/*
316 		 * The field is large enough to hold the maximum integer, so we can
317 		 * never overflow it.
318 		 */
319 		return (FALSE);
320 	}
321 
322 	if (value >= ((acpi_integer) 1 << obj_desc->common_field.bit_length)) {
323 		/*
324 		 * The Value is larger than the maximum value that can fit into
325 		 * the register.
326 		 */
327 		return (TRUE);
328 	}
329 
330 	/* The Value will fit into the field with no truncation */
331 
332 	return (FALSE);
333 }
334 
335 
336 /*******************************************************************************
337  *
338  * FUNCTION:    acpi_ex_field_datum_io
339  *
340  * PARAMETERS:  *obj_desc               - Field to be read
341  *              field_datum_byte_offset - Byte offset of this datum within the
342  *                                        parent field
343  *              *Value                  - Where to store value (must be 64 bits)
344  *              read_write              - Read or Write flag
345  *
346  * RETURN:      Status
347  *
348  * DESCRIPTION: Read or Write a single datum of a field.  The field_type is
349  *              demultiplexed here to handle the different types of fields
350  *              (buffer_field, region_field, index_field, bank_field)
351  *
352  ******************************************************************************/
353 
354 acpi_status
acpi_ex_field_datum_io(union acpi_operand_object * obj_desc,u32 field_datum_byte_offset,acpi_integer * value,u32 read_write)355 acpi_ex_field_datum_io (
356 	union acpi_operand_object       *obj_desc,
357 	u32                             field_datum_byte_offset,
358 	acpi_integer                    *value,
359 	u32                             read_write)
360 {
361 	acpi_status                     status;
362 	acpi_integer                    local_value;
363 
364 
365 	ACPI_FUNCTION_TRACE_U32 ("ex_field_datum_io", field_datum_byte_offset);
366 
367 
368 	if (read_write == ACPI_READ) {
369 		if (!value) {
370 			local_value = 0;
371 			value = &local_value; /* To support reads without saving return value */
372 		}
373 
374 		/* Clear the entire return buffer first, [Very Important!] */
375 
376 		*value = 0;
377 	}
378 
379 	/*
380 	 * The four types of fields are:
381 	 *
382 	 * buffer_field - Read/write from/to a Buffer
383 	 * region_field - Read/write from/to a Operation Region.
384 	 * bank_field  - Write to a Bank Register, then read/write from/to an op_region
385 	 * index_field - Write to an Index Register, then read/write from/to a Data Register
386 	 */
387 	switch (ACPI_GET_OBJECT_TYPE (obj_desc)) {
388 	case ACPI_TYPE_BUFFER_FIELD:
389 		/*
390 		 * If the buffer_field arguments have not been previously evaluated,
391 		 * evaluate them now and save the results.
392 		 */
393 		if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
394 			status = acpi_ds_get_buffer_field_arguments (obj_desc);
395 			if (ACPI_FAILURE (status)) {
396 				return_ACPI_STATUS (status);
397 			}
398 		}
399 
400 		if (read_write == ACPI_READ) {
401 			/*
402 			 * Copy the data from the source buffer.
403 			 * Length is the field width in bytes.
404 			 */
405 			ACPI_MEMCPY (value, (obj_desc->buffer_field.buffer_obj)->buffer.pointer
406 					  + obj_desc->buffer_field.base_byte_offset
407 					  + field_datum_byte_offset,
408 					  obj_desc->common_field.access_byte_width);
409 		}
410 		else {
411 			/*
412 			 * Copy the data to the target buffer.
413 			 * Length is the field width in bytes.
414 			 */
415 			ACPI_MEMCPY ((obj_desc->buffer_field.buffer_obj)->buffer.pointer
416 					+ obj_desc->buffer_field.base_byte_offset
417 					+ field_datum_byte_offset,
418 					value, obj_desc->common_field.access_byte_width);
419 		}
420 
421 		status = AE_OK;
422 		break;
423 
424 
425 	case ACPI_TYPE_LOCAL_BANK_FIELD:
426 
427 		/* Ensure that the bank_value is not beyond the capacity of the register */
428 
429 		if (acpi_ex_register_overflow (obj_desc->bank_field.bank_obj,
430 				  (acpi_integer) obj_desc->bank_field.value)) {
431 			return_ACPI_STATUS (AE_AML_REGISTER_LIMIT);
432 		}
433 
434 		/*
435 		 * For bank_fields, we must write the bank_value to the bank_register
436 		 * (itself a region_field) before we can access the data.
437 		 */
438 		status = acpi_ex_insert_into_field (obj_desc->bank_field.bank_obj,
439 				 &obj_desc->bank_field.value,
440 				 sizeof (obj_desc->bank_field.value));
441 		if (ACPI_FAILURE (status)) {
442 			return_ACPI_STATUS (status);
443 		}
444 
445 		/*
446 		 * Now that the Bank has been selected, fall through to the
447 		 * region_field case and write the datum to the Operation Region
448 		 */
449 
450 		/*lint -fallthrough */
451 
452 
453 	case ACPI_TYPE_LOCAL_REGION_FIELD:
454 		/*
455 		 * For simple region_fields, we just directly access the owning
456 		 * Operation Region.
457 		 */
458 		status = acpi_ex_access_region (obj_desc, field_datum_byte_offset, value,
459 				  read_write);
460 		break;
461 
462 
463 	case ACPI_TYPE_LOCAL_INDEX_FIELD:
464 
465 
466 		/* Ensure that the index_value is not beyond the capacity of the register */
467 
468 		if (acpi_ex_register_overflow (obj_desc->index_field.index_obj,
469 				  (acpi_integer) obj_desc->index_field.value)) {
470 			return_ACPI_STATUS (AE_AML_REGISTER_LIMIT);
471 		}
472 
473 		/* Write the index value to the index_register (itself a region_field) */
474 
475 		field_datum_byte_offset += obj_desc->index_field.value;
476 
477 		ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
478 				"Write to Index Register: Value %8.8X\n",
479 				field_datum_byte_offset));
480 
481 		status = acpi_ex_insert_into_field (obj_desc->index_field.index_obj,
482 				 &field_datum_byte_offset,
483 				 sizeof (field_datum_byte_offset));
484 		if (ACPI_FAILURE (status)) {
485 			return_ACPI_STATUS (status);
486 		}
487 
488 		ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
489 				"I/O to Data Register: value_ptr %p\n",
490 				value));
491 
492 		if (read_write == ACPI_READ) {
493 			/* Read the datum from the data_register */
494 
495 			status = acpi_ex_extract_from_field (obj_desc->index_field.data_obj,
496 					  value, sizeof (acpi_integer));
497 		}
498 		else {
499 			/* Write the datum to the data_register */
500 
501 			status = acpi_ex_insert_into_field (obj_desc->index_field.data_obj,
502 					  value, sizeof (acpi_integer));
503 		}
504 		break;
505 
506 
507 	default:
508 
509 		ACPI_REPORT_ERROR (("Wrong object type in field I/O %X\n",
510 			ACPI_GET_OBJECT_TYPE (obj_desc)));
511 		status = AE_AML_INTERNAL;
512 		break;
513 	}
514 
515 	if (ACPI_SUCCESS (status)) {
516 		if (read_write == ACPI_READ) {
517 			ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Value Read %8.8X%8.8X, Width %d\n",
518 					   ACPI_FORMAT_UINT64 (*value),
519 					   obj_desc->common_field.access_byte_width));
520 		}
521 		else {
522 			ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Value Written %8.8X%8.8X, Width %d\n",
523 					   ACPI_FORMAT_UINT64 (*value),
524 					   obj_desc->common_field.access_byte_width));
525 		}
526 	}
527 
528 	return_ACPI_STATUS (status);
529 }
530 
531 
532 /*******************************************************************************
533  *
534  * FUNCTION:    acpi_ex_write_with_update_rule
535  *
536  * PARAMETERS:  *obj_desc           - Field to be set
537  *              Value               - Value to store
538  *
539  * RETURN:      Status
540  *
541  * DESCRIPTION: Apply the field update rule to a field write
542  *
543  ******************************************************************************/
544 
545 acpi_status
acpi_ex_write_with_update_rule(union acpi_operand_object * obj_desc,acpi_integer mask,acpi_integer field_value,u32 field_datum_byte_offset)546 acpi_ex_write_with_update_rule (
547 	union acpi_operand_object       *obj_desc,
548 	acpi_integer                    mask,
549 	acpi_integer                    field_value,
550 	u32                             field_datum_byte_offset)
551 {
552 	acpi_status                     status = AE_OK;
553 	acpi_integer                    merged_value;
554 	acpi_integer                    current_value;
555 
556 
557 	ACPI_FUNCTION_TRACE_U32 ("ex_write_with_update_rule", mask);
558 
559 
560 	/* Start with the new bits  */
561 
562 	merged_value = field_value;
563 
564 	/* If the mask is all ones, we don't need to worry about the update rule */
565 
566 	if (mask != ACPI_INTEGER_MAX) {
567 		/* Decode the update rule */
568 
569 		switch (obj_desc->common_field.field_flags & AML_FIELD_UPDATE_RULE_MASK) {
570 		case AML_FIELD_UPDATE_PRESERVE:
571 			/*
572 			 * Check if update rule needs to be applied (not if mask is all
573 			 * ones)  The left shift drops the bits we want to ignore.
574 			 */
575 			if ((~mask << (ACPI_MUL_8 (sizeof (mask)) -
576 					 ACPI_MUL_8 (obj_desc->common_field.access_byte_width))) != 0) {
577 				/*
578 				 * Read the current contents of the byte/word/dword containing
579 				 * the field, and merge with the new field value.
580 				 */
581 				status = acpi_ex_field_datum_io (obj_desc, field_datum_byte_offset,
582 						  &current_value, ACPI_READ);
583 				if (ACPI_FAILURE (status)) {
584 					return_ACPI_STATUS (status);
585 				}
586 
587 				merged_value |= (current_value & ~mask);
588 			}
589 			break;
590 
591 		case AML_FIELD_UPDATE_WRITE_AS_ONES:
592 
593 			/* Set positions outside the field to all ones */
594 
595 			merged_value |= ~mask;
596 			break;
597 
598 		case AML_FIELD_UPDATE_WRITE_AS_ZEROS:
599 
600 			/* Set positions outside the field to all zeros */
601 
602 			merged_value &= mask;
603 			break;
604 
605 		default:
606 
607 			ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
608 				"write_with_update_rule: Unknown update_rule setting: %X\n",
609 				(obj_desc->common_field.field_flags & AML_FIELD_UPDATE_RULE_MASK)));
610 			return_ACPI_STATUS (AE_AML_OPERAND_VALUE);
611 		}
612 	}
613 
614 	ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
615 		"Mask %8.8X%8.8X, datum_offset %X, Width %X, Value %8.8X%8.8X, merged_value %8.8X%8.8X\n",
616 		ACPI_FORMAT_UINT64 (mask),
617 		field_datum_byte_offset,
618 		obj_desc->common_field.access_byte_width,
619 		ACPI_FORMAT_UINT64 (field_value),
620 		ACPI_FORMAT_UINT64 (merged_value)));
621 
622 	/* Write the merged value */
623 
624 	status = acpi_ex_field_datum_io (obj_desc, field_datum_byte_offset,
625 			  &merged_value, ACPI_WRITE);
626 
627 	return_ACPI_STATUS (status);
628 }
629 
630 
631 /*******************************************************************************
632  *
633  * FUNCTION:    acpi_ex_get_buffer_datum
634  *
635  * PARAMETERS:  Datum               - Where the Datum is returned
636  *              Buffer              - Raw field buffer
637  *              buffer_length       - Entire length (used for big-endian only)
638  *              byte_granularity    - 1/2/4/8 Granularity of the field
639  *                                    (aka Datum Size)
640  *              buffer_offset       - Datum offset into the buffer
641  *
642  * RETURN:      none
643  *
644  * DESCRIPTION: Get a datum from the buffer according to the buffer field
645  *              byte granularity
646  *
647  ******************************************************************************/
648 
649 void
acpi_ex_get_buffer_datum(acpi_integer * datum,void * buffer,u32 buffer_length,u32 byte_granularity,u32 buffer_offset)650 acpi_ex_get_buffer_datum (
651 	acpi_integer                    *datum,
652 	void                            *buffer,
653 	u32                             buffer_length,
654 	u32                             byte_granularity,
655 	u32                             buffer_offset)
656 {
657 	u32                             index;
658 
659 
660 	ACPI_FUNCTION_TRACE_U32 ("ex_get_buffer_datum", byte_granularity);
661 
662 
663 	/* Get proper index into buffer (handles big/little endian) */
664 
665 	index = ACPI_BUFFER_INDEX (buffer_length, buffer_offset, byte_granularity);
666 
667 	/* Move the requested number of bytes */
668 
669 	switch (byte_granularity) {
670 	case ACPI_FIELD_BYTE_GRANULARITY:
671 
672 		*datum = ((u8 *) buffer) [index];
673 		break;
674 
675 	case ACPI_FIELD_WORD_GRANULARITY:
676 
677 		ACPI_MOVE_16_TO_64 (datum, &(((u16 *) buffer) [index]));
678 		break;
679 
680 	case ACPI_FIELD_DWORD_GRANULARITY:
681 
682 		ACPI_MOVE_32_TO_64 (datum, &(((u32 *) buffer) [index]));
683 		break;
684 
685 	case ACPI_FIELD_QWORD_GRANULARITY:
686 
687 		ACPI_MOVE_64_TO_64 (datum, &(((u64 *) buffer) [index]));
688 		break;
689 
690 	default:
691 		/* Should not get here */
692 		break;
693 	}
694 
695 	return_VOID;
696 }
697 
698 
699 /*******************************************************************************
700  *
701  * FUNCTION:    acpi_ex_set_buffer_datum
702  *
703  * PARAMETERS:  merged_datum        - Value to store
704  *              Buffer              - Receiving buffer
705  *              buffer_length       - Entire length (used for big-endian only)
706  *              byte_granularity    - 1/2/4/8 Granularity of the field
707  *                                    (aka Datum Size)
708  *              buffer_offset       - Datum offset into the buffer
709  *
710  * RETURN:      none
711  *
712  * DESCRIPTION: Store the merged datum to the buffer according to the
713  *              byte granularity
714  *
715  ******************************************************************************/
716 
717 void
acpi_ex_set_buffer_datum(acpi_integer merged_datum,void * buffer,u32 buffer_length,u32 byte_granularity,u32 buffer_offset)718 acpi_ex_set_buffer_datum (
719 	acpi_integer                    merged_datum,
720 	void                            *buffer,
721 	u32                             buffer_length,
722 	u32                             byte_granularity,
723 	u32                             buffer_offset)
724 {
725 	u32                             index;
726 
727 
728 	ACPI_FUNCTION_TRACE_U32 ("ex_set_buffer_datum", byte_granularity);
729 
730 
731 	/* Get proper index into buffer (handles big/little endian) */
732 
733 	index = ACPI_BUFFER_INDEX (buffer_length, buffer_offset, byte_granularity);
734 
735 	/* Move the requested number of bytes */
736 
737 	switch (byte_granularity) {
738 	case ACPI_FIELD_BYTE_GRANULARITY:
739 
740 		((u8 *) buffer) [index] = (u8) merged_datum;
741 		break;
742 
743 	case ACPI_FIELD_WORD_GRANULARITY:
744 
745 		ACPI_MOVE_64_TO_16 (&(((u16 *) buffer)[index]), &merged_datum);
746 		break;
747 
748 	case ACPI_FIELD_DWORD_GRANULARITY:
749 
750 		ACPI_MOVE_64_TO_32 (&(((u32 *) buffer)[index]), &merged_datum);
751 		break;
752 
753 	case ACPI_FIELD_QWORD_GRANULARITY:
754 
755 		ACPI_MOVE_64_TO_64 (&(((u64 *) buffer)[index]), &merged_datum);
756 		break;
757 
758 	default:
759 		/* Should not get here */
760 		break;
761 	}
762 
763 	return_VOID;
764 }
765 
766 
767 /*******************************************************************************
768  *
769  * FUNCTION:    acpi_ex_extract_from_field
770  *
771  * PARAMETERS:  *obj_desc           - Field to be read
772  *              *Value              - Where to store value
773  *
774  * RETURN:      Status
775  *
776  * DESCRIPTION: Retrieve the value of the given field
777  *
778  ******************************************************************************/
779 
780 acpi_status
acpi_ex_extract_from_field(union acpi_operand_object * obj_desc,void * buffer,u32 buffer_length)781 acpi_ex_extract_from_field (
782 	union acpi_operand_object       *obj_desc,
783 	void                            *buffer,
784 	u32                             buffer_length)
785 {
786 	acpi_status                     status;
787 	u32                             field_datum_byte_offset;
788 	u32                             buffer_datum_offset;
789 	acpi_integer                    previous_raw_datum = 0;
790 	acpi_integer                    this_raw_datum = 0;
791 	acpi_integer                    merged_datum = 0;
792 	u32                             byte_field_length;
793 	u32                             datum_count;
794 	u32                             i;
795 
796 
797 	ACPI_FUNCTION_TRACE ("ex_extract_from_field");
798 
799 
800 	/*
801 	 * The field must fit within the caller's buffer
802 	 */
803 	byte_field_length = ACPI_ROUND_BITS_UP_TO_BYTES (obj_desc->common_field.bit_length);
804 	if (byte_field_length > buffer_length) {
805 		ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
806 			"Field size %X (bytes) too large for buffer (%X)\n",
807 			byte_field_length, buffer_length));
808 
809 		return_ACPI_STATUS (AE_BUFFER_OVERFLOW);
810 	}
811 
812 	/* Convert field byte count to datum count, round up if necessary */
813 
814 	datum_count = ACPI_ROUND_UP_TO (byte_field_length,
815 			   obj_desc->common_field.access_byte_width);
816 
817 	/*
818 	 * If the field is not aligned on a datum boundary and does not
819 	 * fit within a single datum, we must read an extra datum.
820 	 *
821 	 * We could just split the aligned and non-aligned cases since the
822 	 * aligned case is so very simple, but this would require more code.
823 	 */
824 	if ((obj_desc->common_field.end_field_valid_bits != 0)    &&
825 		(!(obj_desc->common_field.flags & AOPOBJ_SINGLE_DATUM))) {
826 		datum_count++;
827 	}
828 
829 	ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
830 		"byte_len %X, datum_len %X, byte_gran %X\n",
831 		byte_field_length, datum_count,obj_desc->common_field.access_byte_width));
832 
833 	/*
834 	 * Clear the caller's buffer (the whole buffer length as given)
835 	 * This is very important, especially in the cases where the buffer
836 	 * is longer than the size of the field.
837 	 */
838 	ACPI_MEMSET (buffer, 0, buffer_length);
839 
840 	field_datum_byte_offset = 0;
841 	buffer_datum_offset= 0;
842 
843 	/* Read the entire field */
844 
845 	for (i = 0; i < datum_count; i++) {
846 		status = acpi_ex_field_datum_io (obj_desc, field_datum_byte_offset,
847 				  &this_raw_datum, ACPI_READ);
848 		if (ACPI_FAILURE (status)) {
849 			return_ACPI_STATUS (status);
850 		}
851 
852 		/* We might actually be done if the request fits in one datum */
853 
854 		if ((datum_count == 1) &&
855 			(obj_desc->common_field.flags & AOPOBJ_SINGLE_DATUM)) {
856 			/* 1) Shift the valid data bits down to start at bit 0 */
857 
858 			merged_datum = (this_raw_datum >> obj_desc->common_field.start_field_bit_offset);
859 
860 			/* 2) Mask off any upper unused bits (bits not part of the field) */
861 
862 			if (obj_desc->common_field.end_buffer_valid_bits) {
863 				merged_datum &= ACPI_MASK_BITS_ABOVE (obj_desc->common_field.end_buffer_valid_bits);
864 			}
865 
866 			/* Store the datum to the caller buffer */
867 
868 			acpi_ex_set_buffer_datum (merged_datum, buffer, buffer_length,
869 					obj_desc->common_field.access_byte_width, buffer_datum_offset);
870 
871 			return_ACPI_STATUS (AE_OK);
872 		}
873 
874 		/* Special handling for the last datum to ignore extra bits */
875 
876 		if ((i >= (datum_count -1))          &&
877 			(obj_desc->common_field.end_field_valid_bits)) {
878 			/*
879 			 * This is the last iteration of the loop.  We need to clear
880 			 * any unused bits (bits that are not part of this field) before
881 			 * we store the final merged datum into the caller buffer.
882 			 */
883 			this_raw_datum &=
884 				ACPI_MASK_BITS_ABOVE (obj_desc->common_field.end_field_valid_bits);
885 		}
886 
887 		/*
888 		 * Create the (possibly) merged datum to be stored to the caller buffer
889 		 */
890 		if (obj_desc->common_field.start_field_bit_offset == 0) {
891 			/* Field is not skewed and we can just copy the datum */
892 
893 			acpi_ex_set_buffer_datum (this_raw_datum, buffer, buffer_length,
894 					obj_desc->common_field.access_byte_width, buffer_datum_offset);
895 			buffer_datum_offset++;
896 		}
897 		else {
898 			/* Not aligned -- on the first iteration, just save the datum */
899 
900 			if (i != 0) {
901 				/*
902 				 * Put together the appropriate bits of the two raw data to make a
903 				 * single complete field datum
904 				 *
905 				 * 1) Normalize the first datum down to bit 0
906 				 */
907 				merged_datum = (previous_raw_datum >> obj_desc->common_field.start_field_bit_offset);
908 
909 				/* 2) Insert the second datum "above" the first datum */
910 
911 				merged_datum |= (this_raw_datum << obj_desc->common_field.datum_valid_bits);
912 
913 				acpi_ex_set_buffer_datum (merged_datum, buffer, buffer_length,
914 						obj_desc->common_field.access_byte_width, buffer_datum_offset);
915 				buffer_datum_offset++;
916 			}
917 
918 			/*
919 			 * Save the raw datum that was just acquired since it may contain bits
920 			 * of the *next* field datum
921 			 */
922 			previous_raw_datum = this_raw_datum;
923 		}
924 
925 		field_datum_byte_offset += obj_desc->common_field.access_byte_width;
926 	}
927 
928 	/* For non-aligned case, there is one last datum to insert */
929 
930 	if (obj_desc->common_field.start_field_bit_offset != 0) {
931 		merged_datum = (this_raw_datum >> obj_desc->common_field.start_field_bit_offset);
932 
933 		acpi_ex_set_buffer_datum (merged_datum, buffer, buffer_length,
934 				obj_desc->common_field.access_byte_width, buffer_datum_offset);
935 	}
936 
937 	return_ACPI_STATUS (AE_OK);
938 }
939 
940 
941 /*******************************************************************************
942  *
943  * FUNCTION:    acpi_ex_insert_into_field
944  *
945  * PARAMETERS:  *obj_desc           - Field to be set
946  *              Buffer              - Value to store
947  *
948  * RETURN:      Status
949  *
950  * DESCRIPTION: Store the value into the given field
951  *
952  ******************************************************************************/
953 
954 acpi_status
acpi_ex_insert_into_field(union acpi_operand_object * obj_desc,void * buffer,u32 buffer_length)955 acpi_ex_insert_into_field (
956 	union acpi_operand_object       *obj_desc,
957 	void                            *buffer,
958 	u32                             buffer_length)
959 {
960 	acpi_status                     status;
961 	u32                             field_datum_byte_offset;
962 	u32                             datum_offset;
963 	acpi_integer                    mask;
964 	acpi_integer                    merged_datum;
965 	acpi_integer                    previous_raw_datum;
966 	acpi_integer                    this_raw_datum;
967 	u32                             byte_field_length;
968 	u32                             datum_count;
969 
970 
971 	ACPI_FUNCTION_TRACE ("ex_insert_into_field");
972 
973 
974 	/*
975 	 * Incoming buffer must be at least as long as the field, we do not
976 	 * allow "partial" field writes.  We do not care if the buffer is
977 	 * larger than the field, this typically happens when an integer is
978 	 * written to a field that is actually smaller than an integer.
979 	 */
980 	byte_field_length = ACPI_ROUND_BITS_UP_TO_BYTES (
981 			 obj_desc->common_field.bit_length);
982 	if (buffer_length < byte_field_length) {
983 		ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
984 			"Buffer length %X too small for field %X\n",
985 			buffer_length, byte_field_length));
986 
987 		return_ACPI_STATUS (AE_BUFFER_OVERFLOW);
988 	}
989 
990 	byte_field_length = ACPI_ROUND_BITS_UP_TO_BYTES (
991 			 obj_desc->common_field.start_field_bit_offset +
992 			 obj_desc->common_field.bit_length);
993 
994 	/* Convert byte count to datum count, round up if necessary */
995 
996 	datum_count = ACPI_ROUND_UP_TO (byte_field_length,
997 			  obj_desc->common_field.access_byte_width);
998 
999 	ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
1000 		"Bytes %X, Datums %X, byte_gran %X\n",
1001 		byte_field_length, datum_count, obj_desc->common_field.access_byte_width));
1002 
1003 	/*
1004 	 * Break the request into up to three parts (similar to an I/O request):
1005 	 * 1) non-aligned part at start
1006 	 * 2) aligned part in middle
1007 	 * 3) non-aligned part at the end
1008 	 */
1009 	field_datum_byte_offset = 0;
1010 	datum_offset= 0;
1011 
1012 	/* Get a single datum from the caller's buffer */
1013 
1014 	acpi_ex_get_buffer_datum (&previous_raw_datum, buffer, buffer_length,
1015 			obj_desc->common_field.access_byte_width, datum_offset);
1016 
1017 	/*
1018 	 * Part1:
1019 	 * Write a partial field datum if field does not begin on a datum boundary
1020 	 * Note: The code in this section also handles the aligned case
1021 	 *
1022 	 * Construct Mask with 1 bits where the field is, 0 bits elsewhere
1023 	 * (Only the bottom 5 bits of bit_length are valid for a shift operation)
1024 	 *
1025 	 * Mask off bits that are "below" the field (if any)
1026 	 */
1027 	mask = ACPI_MASK_BITS_BELOW (obj_desc->common_field.start_field_bit_offset);
1028 
1029 	/* If the field fits in one datum, may need to mask upper bits */
1030 
1031 	if ((obj_desc->common_field.flags & AOPOBJ_SINGLE_DATUM) &&
1032 		 obj_desc->common_field.end_field_valid_bits) {
1033 		/* There are bits above the field, mask them off also */
1034 
1035 		mask &= ACPI_MASK_BITS_ABOVE (obj_desc->common_field.end_field_valid_bits);
1036 	}
1037 
1038 	/* Shift and mask the value into the field position */
1039 
1040 	merged_datum = (previous_raw_datum << obj_desc->common_field.start_field_bit_offset);
1041 	merged_datum &= mask;
1042 
1043 	/* Apply the update rule (if necessary) and write the datum to the field */
1044 
1045 	status = acpi_ex_write_with_update_rule (obj_desc, mask, merged_datum,
1046 			   field_datum_byte_offset);
1047 	if (ACPI_FAILURE (status)) {
1048 		return_ACPI_STATUS (status);
1049 	}
1050 
1051 	/* We just wrote the first datum */
1052 
1053 	datum_offset++;
1054 
1055 	/* If the entire field fits within one datum, we are done. */
1056 
1057 	if ((datum_count == 1) &&
1058 	   (obj_desc->common_field.flags & AOPOBJ_SINGLE_DATUM)) {
1059 		return_ACPI_STATUS (AE_OK);
1060 	}
1061 
1062 	/*
1063 	 * Part2:
1064 	 * Write the aligned data.
1065 	 *
1066 	 * We don't need to worry about the update rule for these data, because
1067 	 * all of the bits in each datum are part of the field.
1068 	 *
1069 	 * The last datum must be special cased because it might contain bits
1070 	 * that are not part of the field -- therefore the "update rule" must be
1071 	 * applied in Part3 below.
1072 	 */
1073 	while (datum_offset < datum_count) {
1074 		field_datum_byte_offset += obj_desc->common_field.access_byte_width;
1075 
1076 		/*
1077 		 * Get the next raw buffer datum.  It may contain bits of the previous
1078 		 * field datum
1079 		 */
1080 		acpi_ex_get_buffer_datum (&this_raw_datum, buffer, buffer_length,
1081 				obj_desc->common_field.access_byte_width, datum_offset);
1082 
1083 		/* Create the field datum based on the field alignment */
1084 
1085 		if (obj_desc->common_field.start_field_bit_offset != 0) {
1086 			/*
1087 			 * Put together appropriate bits of the two raw buffer data to make
1088 			 * a single complete field datum
1089 			 */
1090 			merged_datum =
1091 				(previous_raw_datum >> obj_desc->common_field.datum_valid_bits) |
1092 				(this_raw_datum << obj_desc->common_field.start_field_bit_offset);
1093 		}
1094 		else {
1095 			/* Field began aligned on datum boundary */
1096 
1097 			merged_datum = this_raw_datum;
1098 		}
1099 
1100 		/*
1101 		 * Special handling for the last datum if the field does NOT end on
1102 		 * a datum boundary.  Update Rule must be applied to the bits outside
1103 		 * the field.
1104 		 */
1105 		datum_offset++;
1106 		if ((datum_offset == datum_count) &&
1107 			(obj_desc->common_field.end_field_valid_bits)) {
1108 			/*
1109 			 * If there are dangling non-aligned bits, perform one more merged write
1110 			 * Else - field is aligned at the end, no need for any more writes
1111 			 */
1112 
1113 			/*
1114 			 * Part3:
1115 			 * This is the last datum and the field does not end on a datum boundary.
1116 			 * Build the partial datum and write with the update rule.
1117 			 *
1118 			 * Mask off the unused bits above (after) the end-of-field
1119 			 */
1120 			mask = ACPI_MASK_BITS_ABOVE (obj_desc->common_field.end_field_valid_bits);
1121 			merged_datum &= mask;
1122 
1123 			/* Write the last datum with the update rule */
1124 
1125 			status = acpi_ex_write_with_update_rule (obj_desc, mask, merged_datum,
1126 					   field_datum_byte_offset);
1127 			if (ACPI_FAILURE (status)) {
1128 				return_ACPI_STATUS (status);
1129 			}
1130 		}
1131 		else {
1132 			/* Normal (aligned) case -- write the completed datum */
1133 
1134 			status = acpi_ex_field_datum_io (obj_desc, field_datum_byte_offset,
1135 					  &merged_datum, ACPI_WRITE);
1136 			if (ACPI_FAILURE (status)) {
1137 				return_ACPI_STATUS (status);
1138 			}
1139 		}
1140 
1141 		/*
1142 		 * Save the most recent datum since it may contain bits of the *next*
1143 		 * field datum.  Update current byte offset.
1144 		 */
1145 		previous_raw_datum = this_raw_datum;
1146 	}
1147 
1148 	return_ACPI_STATUS (status);
1149 }
1150 
1151 
1152