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1
2/******************************************************************************
3 *
4 * Module Name: exprep - ACPI AML (p-code) execution - field prep utilities
5 *
6 *****************************************************************************/
7
8/*
9 * Copyright (C) 2000 - 2005, R. Byron Moore
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#include <acpi/acpi.h>
46#include <acpi/acinterp.h>
47#include <acpi/amlcode.h>
48#include <acpi/acnamesp.h>
49
50#define _COMPONENT ACPI_EXECUTER
51ACPI_MODULE_NAME("exprep")
52
53/* Local prototypes */
54static u32
55acpi_ex_decode_field_access(union acpi_operand_object *obj_desc,
56 u8 field_flags, u32 * return_byte_alignment);
57
58#ifdef ACPI_UNDER_DEVELOPMENT
59
60static u32
61acpi_ex_generate_access(u32 field_bit_offset,
62 u32 field_bit_length, u32 region_length);
63
64/*******************************************************************************
65 *
66 * FUNCTION: acpi_ex_generate_access
67 *
68 * PARAMETERS: field_bit_offset - Start of field within parent region/buffer
69 * field_bit_length - Length of field in bits
70 * region_length - Length of parent in bytes
71 *
72 * RETURN: Field granularity (8, 16, 32 or 64) and
73 * byte_alignment (1, 2, 3, or 4)
74 *
75 * DESCRIPTION: Generate an optimal access width for fields defined with the
76 * any_acc keyword.
77 *
78 * NOTE: Need to have the region_length in order to check for boundary
79 * conditions (end-of-region). However, the region_length is a deferred
80 * operation. Therefore, to complete this implementation, the generation
81 * of this access width must be deferred until the region length has
82 * been evaluated.
83 *
84 ******************************************************************************/
85
86static u32
87acpi_ex_generate_access(u32 field_bit_offset,
88 u32 field_bit_length, u32 region_length)
89{
90 u32 field_byte_length;
91 u32 field_byte_offset;
92 u32 field_byte_end_offset;
93 u32 access_byte_width;
94 u32 field_start_offset;
95 u32 field_end_offset;
96 u32 minimum_access_width = 0xFFFFFFFF;
97 u32 minimum_accesses = 0xFFFFFFFF;
98 u32 accesses;
99
100 ACPI_FUNCTION_TRACE("ex_generate_access");
101
102 /* Round Field start offset and length to "minimal" byte boundaries */
103
104 field_byte_offset = ACPI_DIV_8(ACPI_ROUND_DOWN(field_bit_offset, 8));
105 field_byte_end_offset = ACPI_DIV_8(ACPI_ROUND_UP(field_bit_length +
106 field_bit_offset, 8));
107 field_byte_length = field_byte_end_offset - field_byte_offset;
108
109 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
110 "Bit length %d, Bit offset %d\n",
111 field_bit_length, field_bit_offset));
112
113 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
114 "Byte Length %d, Byte Offset %d, End Offset %d\n",
115 field_byte_length, field_byte_offset,
116 field_byte_end_offset));
117
118 /*
119 * Iterative search for the maximum access width that is both aligned
120 * and does not go beyond the end of the region
121 *
122 * Start at byte_acc and work upwards to qword_acc max. (1,2,4,8 bytes)
123 */
124 for (access_byte_width = 1; access_byte_width <= 8;
125 access_byte_width <<= 1) {
126 /*
127 * 1) Round end offset up to next access boundary and make sure that
128 * this does not go beyond the end of the parent region.
129 * 2) When the Access width is greater than the field_byte_length, we
130 * are done. (This does not optimize for the perfectly aligned
131 * case yet).
132 */
133 if (ACPI_ROUND_UP(field_byte_end_offset, access_byte_width) <=
134 region_length) {
135 field_start_offset =
136 ACPI_ROUND_DOWN(field_byte_offset,
137 access_byte_width) /
138 access_byte_width;
139
140 field_end_offset =
141 ACPI_ROUND_UP((field_byte_length +
142 field_byte_offset),
143 access_byte_width) /
144 access_byte_width;
145
146 accesses = field_end_offset - field_start_offset;
147
148 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
149 "access_width %d end is within region\n",
150 access_byte_width));
151
152 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
153 "Field Start %d, Field End %d -- requires %d accesses\n",
154 field_start_offset, field_end_offset,
155 accesses));
156
157 /* Single access is optimal */
158
159 if (accesses <= 1) {
160 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
161 "Entire field can be accessed with one operation of size %d\n",
162 access_byte_width));
163 return_VALUE(access_byte_width);
164 }
165
166 /*
167 * Fits in the region, but requires more than one read/write.
168 * try the next wider access on next iteration
169 */
170 if (accesses < minimum_accesses) {
171 minimum_accesses = accesses;
172 minimum_access_width = access_byte_width;
173 }
174 } else {
175 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
176 "access_width %d end is NOT within region\n",
177 access_byte_width));
178 if (access_byte_width == 1) {
179 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
180 "Field goes beyond end-of-region!\n"));
181
182 /* Field does not fit in the region at all */
183
184 return_VALUE(0);
185 }
186
187 /*
188 * This width goes beyond the end-of-region, back off to
189 * previous access
190 */
191 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
192 "Backing off to previous optimal access width of %d\n",
193 minimum_access_width));
194 return_VALUE(minimum_access_width);
195 }
196 }
197
198 /*
199 * Could not read/write field with one operation,
200 * just use max access width
201 */
202 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
203 "Cannot access field in one operation, using width 8\n"));
204 return_VALUE(8);
205}
206#endif /* ACPI_UNDER_DEVELOPMENT */
207
208/*******************************************************************************
209 *
210 * FUNCTION: acpi_ex_decode_field_access
211 *
212 * PARAMETERS: obj_desc - Field object
213 * field_flags - Encoded fieldflags (contains access bits)
214 * return_byte_alignment - Where the byte alignment is returned
215 *
216 * RETURN: Field granularity (8, 16, 32 or 64) and
217 * byte_alignment (1, 2, 3, or 4)
218 *
219 * DESCRIPTION: Decode the access_type bits of a field definition.
220 *
221 ******************************************************************************/
222
223static u32
224acpi_ex_decode_field_access(union acpi_operand_object *obj_desc,
225 u8 field_flags, u32 * return_byte_alignment)
226{
227 u32 access;
228 u32 byte_alignment;
229 u32 bit_length;
230
231 ACPI_FUNCTION_TRACE("ex_decode_field_access");
232
233 access = (field_flags & AML_FIELD_ACCESS_TYPE_MASK);
234
235 switch (access) {
236 case AML_FIELD_ACCESS_ANY:
237
238#ifdef ACPI_UNDER_DEVELOPMENT
239 byte_alignment =
240 acpi_ex_generate_access(obj_desc->common_field.
241 start_field_bit_offset,
242 obj_desc->common_field.bit_length,
243 0xFFFFFFFF
244 /* Temp until we pass region_length as parameter */
245 );
246 bit_length = byte_alignment * 8;
247#endif
248
249 byte_alignment = 1;
250 bit_length = 8;
251 break;
252
253 case AML_FIELD_ACCESS_BYTE:
254 case AML_FIELD_ACCESS_BUFFER: /* ACPI 2.0 (SMBus Buffer) */
255 byte_alignment = 1;
256 bit_length = 8;
257 break;
258
259 case AML_FIELD_ACCESS_WORD:
260 byte_alignment = 2;
261 bit_length = 16;
262 break;
263
264 case AML_FIELD_ACCESS_DWORD:
265 byte_alignment = 4;
266 bit_length = 32;
267 break;
268
269 case AML_FIELD_ACCESS_QWORD: /* ACPI 2.0 */
270 byte_alignment = 8;
271 bit_length = 64;
272 break;
273
274 default:
275 /* Invalid field access type */
276
277 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
278 "Unknown field access type %X\n", access));
279 return_VALUE(0);
280 }
281
282 if (ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_BUFFER_FIELD) {
283 /*
284 * buffer_field access can be on any byte boundary, so the
285 * byte_alignment is always 1 byte -- regardless of any byte_alignment
286 * implied by the field access type.
287 */
288 byte_alignment = 1;
289 }
290
291 *return_byte_alignment = byte_alignment;
292 return_VALUE(bit_length);
293}
294
295/*******************************************************************************
296 *
297 * FUNCTION: acpi_ex_prep_common_field_object
298 *
299 * PARAMETERS: obj_desc - The field object
300 * field_flags - Access, lock_rule, and update_rule.
301 * The format of a field_flag is described
302 * in the ACPI specification
303 * field_attribute - Special attributes (not used)
304 * field_bit_position - Field start position
305 * field_bit_length - Field length in number of bits
306 *
307 * RETURN: Status
308 *
309 * DESCRIPTION: Initialize the areas of the field object that are common
310 * to the various types of fields. Note: This is very "sensitive"
311 * code because we are solving the general case for field
312 * alignment.
313 *
314 ******************************************************************************/
315
316acpi_status
317acpi_ex_prep_common_field_object(union acpi_operand_object *obj_desc,
318 u8 field_flags,
319 u8 field_attribute,
320 u32 field_bit_position, u32 field_bit_length)
321{
322 u32 access_bit_width;
323 u32 byte_alignment;
324 u32 nearest_byte_address;
325
326 ACPI_FUNCTION_TRACE("ex_prep_common_field_object");
327
328 /*
329 * Note: the structure being initialized is the
330 * ACPI_COMMON_FIELD_INFO; No structure fields outside of the common
331 * area are initialized by this procedure.
332 */
333 obj_desc->common_field.field_flags = field_flags;
334 obj_desc->common_field.attribute = field_attribute;
335 obj_desc->common_field.bit_length = field_bit_length;
336
337 /*
338 * Decode the access type so we can compute offsets. The access type gives
339 * two pieces of information - the width of each field access and the
340 * necessary byte_alignment (address granularity) of the access.
341 *
342 * For any_acc, the access_bit_width is the largest width that is both
343 * necessary and possible in an attempt to access the whole field in one
344 * I/O operation. However, for any_acc, the byte_alignment is always one
345 * byte.
346 *
347 * For all Buffer Fields, the byte_alignment is always one byte.
348 *
349 * For all other access types (Byte, Word, Dword, Qword), the Bitwidth is
350 * the same (equivalent) as the byte_alignment.
351 */
352 access_bit_width = acpi_ex_decode_field_access(obj_desc, field_flags,
353 &byte_alignment);
354 if (!access_bit_width) {
355 return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
356 }
357
358 /* Setup width (access granularity) fields */
359
360 obj_desc->common_field.access_byte_width = (u8)
361 ACPI_DIV_8(access_bit_width); /* 1, 2, 4, 8 */
362
363 obj_desc->common_field.access_bit_width = (u8) access_bit_width;
364
365 /*
366 * base_byte_offset is the address of the start of the field within the
367 * region. It is the byte address of the first *datum* (field-width data
368 * unit) of the field. (i.e., the first datum that contains at least the
369 * first *bit* of the field.)
370 *
371 * Note: byte_alignment is always either equal to the access_bit_width or 8
372 * (Byte access), and it defines the addressing granularity of the parent
373 * region or buffer.
374 */
375 nearest_byte_address =
376 ACPI_ROUND_BITS_DOWN_TO_BYTES(field_bit_position);
377 obj_desc->common_field.base_byte_offset = (u32)
378 ACPI_ROUND_DOWN(nearest_byte_address, byte_alignment);
379
380 /*
381 * start_field_bit_offset is the offset of the first bit of the field within
382 * a field datum.
383 */
384 obj_desc->common_field.start_field_bit_offset = (u8)
385 (field_bit_position -
386 ACPI_MUL_8(obj_desc->common_field.base_byte_offset));
387
388 /*
389 * Does the entire field fit within a single field access element? (datum)
390 * (i.e., without crossing a datum boundary)
391 */
392 if ((obj_desc->common_field.start_field_bit_offset +
393 field_bit_length) <= (u16) access_bit_width) {
394 obj_desc->common.flags |= AOPOBJ_SINGLE_DATUM;
395 }
396
397 return_ACPI_STATUS(AE_OK);
398}
399
400/*******************************************************************************
401 *
402 * FUNCTION: acpi_ex_prep_field_value
403 *
404 * PARAMETERS: Info - Contains all field creation info
405 *
406 * RETURN: Status
407 *
408 * DESCRIPTION: Construct an union acpi_operand_object of type def_field and
409 * connect it to the parent Node.
410 *
411 ******************************************************************************/
412
413acpi_status acpi_ex_prep_field_value(struct acpi_create_field_info *info)
414{
415 union acpi_operand_object *obj_desc;
416 u32 type;
417 acpi_status status;
418
419 ACPI_FUNCTION_TRACE("ex_prep_field_value");
420
421 /* Parameter validation */
422
423 if (info->field_type != ACPI_TYPE_LOCAL_INDEX_FIELD) {
424 if (!info->region_node) {
425 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Null region_node\n"));
426 return_ACPI_STATUS(AE_AML_NO_OPERAND);
427 }
428
429 type = acpi_ns_get_type(info->region_node);
430 if (type != ACPI_TYPE_REGION) {
431 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
432 "Needed Region, found type %X (%s)\n",
433 type, acpi_ut_get_type_name(type)));
434
435 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
436 }
437 }
438
439 /* Allocate a new field object */
440
441 obj_desc = acpi_ut_create_internal_object(info->field_type);
442 if (!obj_desc) {
443 return_ACPI_STATUS(AE_NO_MEMORY);
444 }
445
446 /* Initialize areas of the object that are common to all fields */
447
448 obj_desc->common_field.node = info->field_node;
449 status = acpi_ex_prep_common_field_object(obj_desc, info->field_flags,
450 info->attribute,
451 info->field_bit_position,
452 info->field_bit_length);
453 if (ACPI_FAILURE(status)) {
454 acpi_ut_delete_object_desc(obj_desc);
455 return_ACPI_STATUS(status);
456 }
457
458 /* Initialize areas of the object that are specific to the field type */
459
460 switch (info->field_type) {
461 case ACPI_TYPE_LOCAL_REGION_FIELD:
462
463 obj_desc->field.region_obj =
464 acpi_ns_get_attached_object(info->region_node);
465
466 /* An additional reference for the container */
467
468 acpi_ut_add_reference(obj_desc->field.region_obj);
469
470 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
471 "region_field: bit_off %X, Off %X, Gran %X, Region %p\n",
472 obj_desc->field.start_field_bit_offset,
473 obj_desc->field.base_byte_offset,
474 obj_desc->field.access_byte_width,
475 obj_desc->field.region_obj));
476 break;
477
478 case ACPI_TYPE_LOCAL_BANK_FIELD:
479
480 obj_desc->bank_field.value = info->bank_value;
481 obj_desc->bank_field.region_obj =
482 acpi_ns_get_attached_object(info->region_node);
483 obj_desc->bank_field.bank_obj =
484 acpi_ns_get_attached_object(info->register_node);
485
486 /* An additional reference for the attached objects */
487
488 acpi_ut_add_reference(obj_desc->bank_field.region_obj);
489 acpi_ut_add_reference(obj_desc->bank_field.bank_obj);
490
491 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
492 "Bank Field: bit_off %X, Off %X, Gran %X, Region %p, bank_reg %p\n",
493 obj_desc->bank_field.start_field_bit_offset,
494 obj_desc->bank_field.base_byte_offset,
495 obj_desc->field.access_byte_width,
496 obj_desc->bank_field.region_obj,
497 obj_desc->bank_field.bank_obj));
498 break;
499
500 case ACPI_TYPE_LOCAL_INDEX_FIELD:
501
502 obj_desc->index_field.index_obj =
503 acpi_ns_get_attached_object(info->register_node);
504 obj_desc->index_field.data_obj =
505 acpi_ns_get_attached_object(info->data_register_node);
506 obj_desc->index_field.value = (u32)
507 (info->field_bit_position /
508 ACPI_MUL_8(obj_desc->field.access_byte_width));
509
510 if (!obj_desc->index_field.data_obj
511 || !obj_desc->index_field.index_obj) {
512 ACPI_REPORT_ERROR(("Null Index Object during field prep\n"));
513 acpi_ut_delete_object_desc(obj_desc);
514 return_ACPI_STATUS(AE_AML_INTERNAL);
515 }
516
517 /* An additional reference for the attached objects */
518
519 acpi_ut_add_reference(obj_desc->index_field.data_obj);
520 acpi_ut_add_reference(obj_desc->index_field.index_obj);
521
522 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
523 "index_field: bit_off %X, Off %X, Value %X, Gran %X, Index %p, Data %p\n",
524 obj_desc->index_field.start_field_bit_offset,
525 obj_desc->index_field.base_byte_offset,
526 obj_desc->index_field.value,
527 obj_desc->field.access_byte_width,
528 obj_desc->index_field.index_obj,
529 obj_desc->index_field.data_obj));
530 break;
531
532 default:
533 /* No other types should get here */
534 break;
535 }
536
537 /*
538 * Store the constructed descriptor (obj_desc) into the parent Node,
539 * preserving the current type of that named_obj.
540 */
541 status = acpi_ns_attach_object(info->field_node, obj_desc,
542 acpi_ns_get_type(info->field_node));
543
544 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
545 "Set named_obj %p [%4.4s], obj_desc %p\n",
546 info->field_node,
547 acpi_ut_get_node_name(info->field_node), obj_desc));
548
549 /* Remove local reference to the object */
550
551 acpi_ut_remove_reference(obj_desc);
552 return_ACPI_STATUS(status);
553}