2 /******************************************************************************
4 * Module Name: exprep - ACPI AML (p-code) execution - field prep utilities
6 *****************************************************************************/
9 * Copyright (C) 2000 - 2005, R. Byron Moore
10 * All rights reserved.
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
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.
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.
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.
46 #include <acpi/acpi.h>
47 #include <acpi/acinterp.h>
48 #include <acpi/amlcode.h>
49 #include <acpi/acnamesp.h>
52 #define _COMPONENT ACPI_EXECUTER
53 ACPI_MODULE_NAME ("exprep")
55 /* Local prototypes */
58 acpi_ex_decode_field_access (
59 union acpi_operand_object
*obj_desc
,
61 u32
*return_byte_alignment
);
64 #ifdef ACPI_UNDER_DEVELOPMENT
67 acpi_ex_generate_access (
72 /*******************************************************************************
74 * FUNCTION: acpi_ex_generate_access
76 * PARAMETERS: field_bit_offset - Start of field within parent region/buffer
77 * field_bit_length - Length of field in bits
78 * region_length - Length of parent in bytes
80 * RETURN: Field granularity (8, 16, 32 or 64) and
81 * byte_alignment (1, 2, 3, or 4)
83 * DESCRIPTION: Generate an optimal access width for fields defined with the
86 * NOTE: Need to have the region_length in order to check for boundary
87 * conditions (end-of-region). However, the region_length is a deferred
88 * operation. Therefore, to complete this implementation, the generation
89 * of this access width must be deferred until the region length has
92 ******************************************************************************/
95 acpi_ex_generate_access (
100 u32 field_byte_length
;
101 u32 field_byte_offset
;
102 u32 field_byte_end_offset
;
103 u32 access_byte_width
;
104 u32 field_start_offset
;
105 u32 field_end_offset
;
106 u32 minimum_access_width
= 0xFFFFFFFF;
107 u32 minimum_accesses
= 0xFFFFFFFF;
111 ACPI_FUNCTION_TRACE ("ex_generate_access");
114 /* Round Field start offset and length to "minimal" byte boundaries */
116 field_byte_offset
= ACPI_DIV_8 (ACPI_ROUND_DOWN (field_bit_offset
, 8));
117 field_byte_end_offset
= ACPI_DIV_8 (ACPI_ROUND_UP (field_bit_length
+
118 field_bit_offset
, 8));
119 field_byte_length
= field_byte_end_offset
- field_byte_offset
;
121 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD
,
122 "Bit length %d, Bit offset %d\n",
123 field_bit_length
, field_bit_offset
));
125 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD
,
126 "Byte Length %d, Byte Offset %d, End Offset %d\n",
127 field_byte_length
, field_byte_offset
, field_byte_end_offset
));
130 * Iterative search for the maximum access width that is both aligned
131 * and does not go beyond the end of the region
133 * Start at byte_acc and work upwards to qword_acc max. (1,2,4,8 bytes)
135 for (access_byte_width
= 1; access_byte_width
<= 8; access_byte_width
<<= 1) {
137 * 1) Round end offset up to next access boundary and make sure that
138 * this does not go beyond the end of the parent region.
139 * 2) When the Access width is greater than the field_byte_length, we
140 * are done. (This does not optimize for the perfectly aligned
143 if (ACPI_ROUND_UP (field_byte_end_offset
, access_byte_width
) <= region_length
) {
145 ACPI_ROUND_DOWN (field_byte_offset
, access_byte_width
) /
149 ACPI_ROUND_UP ((field_byte_length
+ field_byte_offset
),
150 access_byte_width
) / access_byte_width
;
152 accesses
= field_end_offset
- field_start_offset
;
154 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD
,
155 "access_width %d end is within region\n", access_byte_width
));
157 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD
,
158 "Field Start %d, Field End %d -- requires %d accesses\n",
159 field_start_offset
, field_end_offset
, accesses
));
161 /* Single access is optimal */
164 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD
,
165 "Entire field can be accessed with one operation of size %d\n",
167 return_VALUE (access_byte_width
);
171 * Fits in the region, but requires more than one read/write.
172 * try the next wider access on next iteration
174 if (accesses
< minimum_accesses
) {
175 minimum_accesses
= accesses
;
176 minimum_access_width
= access_byte_width
;
180 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD
,
181 "access_width %d end is NOT within region\n", access_byte_width
));
182 if (access_byte_width
== 1) {
183 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD
,
184 "Field goes beyond end-of-region!\n"));
186 /* Field does not fit in the region at all */
192 * This width goes beyond the end-of-region, back off to
195 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD
,
196 "Backing off to previous optimal access width of %d\n",
197 minimum_access_width
));
198 return_VALUE (minimum_access_width
);
203 * Could not read/write field with one operation,
204 * just use max access width
206 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD
,
207 "Cannot access field in one operation, using width 8\n"));
210 #endif /* ACPI_UNDER_DEVELOPMENT */
213 /*******************************************************************************
215 * FUNCTION: acpi_ex_decode_field_access
217 * PARAMETERS: obj_desc - Field object
218 * field_flags - Encoded fieldflags (contains access bits)
219 * return_byte_alignment - Where the byte alignment is returned
221 * RETURN: Field granularity (8, 16, 32 or 64) and
222 * byte_alignment (1, 2, 3, or 4)
224 * DESCRIPTION: Decode the access_type bits of a field definition.
226 ******************************************************************************/
229 acpi_ex_decode_field_access (
230 union acpi_operand_object
*obj_desc
,
232 u32
*return_byte_alignment
)
239 ACPI_FUNCTION_TRACE ("ex_decode_field_access");
242 access
= (field_flags
& AML_FIELD_ACCESS_TYPE_MASK
);
245 case AML_FIELD_ACCESS_ANY
:
247 #ifdef ACPI_UNDER_DEVELOPMENT
249 acpi_ex_generate_access (obj_desc
->common_field
.start_field_bit_offset
,
250 obj_desc
->common_field
.bit_length
,
251 0xFFFFFFFF /* Temp until we pass region_length as parameter */);
252 bit_length
= byte_alignment
* 8;
259 case AML_FIELD_ACCESS_BYTE
:
260 case AML_FIELD_ACCESS_BUFFER
: /* ACPI 2.0 (SMBus Buffer) */
265 case AML_FIELD_ACCESS_WORD
:
270 case AML_FIELD_ACCESS_DWORD
:
275 case AML_FIELD_ACCESS_QWORD
: /* ACPI 2.0 */
281 /* Invalid field access type */
283 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR
,
284 "Unknown field access type %X\n",
289 if (ACPI_GET_OBJECT_TYPE (obj_desc
) == ACPI_TYPE_BUFFER_FIELD
) {
291 * buffer_field access can be on any byte boundary, so the
292 * byte_alignment is always 1 byte -- regardless of any byte_alignment
293 * implied by the field access type.
298 *return_byte_alignment
= byte_alignment
;
299 return_VALUE (bit_length
);
303 /*******************************************************************************
305 * FUNCTION: acpi_ex_prep_common_field_object
307 * PARAMETERS: obj_desc - The field object
308 * field_flags - Access, lock_rule, and update_rule.
309 * The format of a field_flag is described
310 * in the ACPI specification
311 * field_attribute - Special attributes (not used)
312 * field_bit_position - Field start position
313 * field_bit_length - Field length in number of bits
317 * DESCRIPTION: Initialize the areas of the field object that are common
318 * to the various types of fields. Note: This is very "sensitive"
319 * code because we are solving the general case for field
322 ******************************************************************************/
325 acpi_ex_prep_common_field_object (
326 union acpi_operand_object
*obj_desc
,
329 u32 field_bit_position
,
330 u32 field_bit_length
)
332 u32 access_bit_width
;
334 u32 nearest_byte_address
;
337 ACPI_FUNCTION_TRACE ("ex_prep_common_field_object");
341 * Note: the structure being initialized is the
342 * ACPI_COMMON_FIELD_INFO; No structure fields outside of the common
343 * area are initialized by this procedure.
345 obj_desc
->common_field
.field_flags
= field_flags
;
346 obj_desc
->common_field
.attribute
= field_attribute
;
347 obj_desc
->common_field
.bit_length
= field_bit_length
;
350 * Decode the access type so we can compute offsets. The access type gives
351 * two pieces of information - the width of each field access and the
352 * necessary byte_alignment (address granularity) of the access.
354 * For any_acc, the access_bit_width is the largest width that is both
355 * necessary and possible in an attempt to access the whole field in one
356 * I/O operation. However, for any_acc, the byte_alignment is always one
359 * For all Buffer Fields, the byte_alignment is always one byte.
361 * For all other access types (Byte, Word, Dword, Qword), the Bitwidth is
362 * the same (equivalent) as the byte_alignment.
364 access_bit_width
= acpi_ex_decode_field_access (obj_desc
, field_flags
,
366 if (!access_bit_width
) {
367 return_ACPI_STATUS (AE_AML_OPERAND_VALUE
);
370 /* Setup width (access granularity) fields */
372 obj_desc
->common_field
.access_byte_width
= (u8
)
373 ACPI_DIV_8 (access_bit_width
); /* 1, 2, 4, 8 */
375 obj_desc
->common_field
.access_bit_width
= (u8
) access_bit_width
;
378 * base_byte_offset is the address of the start of the field within the
379 * region. It is the byte address of the first *datum* (field-width data
380 * unit) of the field. (i.e., the first datum that contains at least the
381 * first *bit* of the field.)
383 * Note: byte_alignment is always either equal to the access_bit_width or 8
384 * (Byte access), and it defines the addressing granularity of the parent
387 nearest_byte_address
=
388 ACPI_ROUND_BITS_DOWN_TO_BYTES (field_bit_position
);
389 obj_desc
->common_field
.base_byte_offset
= (u32
)
390 ACPI_ROUND_DOWN (nearest_byte_address
, byte_alignment
);
393 * start_field_bit_offset is the offset of the first bit of the field within
396 obj_desc
->common_field
.start_field_bit_offset
= (u8
)
397 (field_bit_position
- ACPI_MUL_8 (obj_desc
->common_field
.base_byte_offset
));
400 * Does the entire field fit within a single field access element? (datum)
401 * (i.e., without crossing a datum boundary)
403 if ((obj_desc
->common_field
.start_field_bit_offset
+ field_bit_length
) <=
404 (u16
) access_bit_width
) {
405 obj_desc
->common
.flags
|= AOPOBJ_SINGLE_DATUM
;
408 return_ACPI_STATUS (AE_OK
);
412 /*******************************************************************************
414 * FUNCTION: acpi_ex_prep_field_value
416 * PARAMETERS: Info - Contains all field creation info
420 * DESCRIPTION: Construct an union acpi_operand_object of type def_field and
421 * connect it to the parent Node.
423 ******************************************************************************/
426 acpi_ex_prep_field_value (
427 struct acpi_create_field_info
*info
)
429 union acpi_operand_object
*obj_desc
;
434 ACPI_FUNCTION_TRACE ("ex_prep_field_value");
437 /* Parameter validation */
439 if (info
->field_type
!= ACPI_TYPE_LOCAL_INDEX_FIELD
) {
440 if (!info
->region_node
) {
441 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR
, "Null region_node\n"));
442 return_ACPI_STATUS (AE_AML_NO_OPERAND
);
445 type
= acpi_ns_get_type (info
->region_node
);
446 if (type
!= ACPI_TYPE_REGION
) {
447 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR
,
448 "Needed Region, found type %X (%s)\n",
449 type
, acpi_ut_get_type_name (type
)));
451 return_ACPI_STATUS (AE_AML_OPERAND_TYPE
);
455 /* Allocate a new field object */
457 obj_desc
= acpi_ut_create_internal_object (info
->field_type
);
459 return_ACPI_STATUS (AE_NO_MEMORY
);
462 /* Initialize areas of the object that are common to all fields */
464 obj_desc
->common_field
.node
= info
->field_node
;
465 status
= acpi_ex_prep_common_field_object (obj_desc
, info
->field_flags
,
466 info
->attribute
, info
->field_bit_position
, info
->field_bit_length
);
467 if (ACPI_FAILURE (status
)) {
468 acpi_ut_delete_object_desc (obj_desc
);
469 return_ACPI_STATUS (status
);
472 /* Initialize areas of the object that are specific to the field type */
474 switch (info
->field_type
) {
475 case ACPI_TYPE_LOCAL_REGION_FIELD
:
477 obj_desc
->field
.region_obj
= acpi_ns_get_attached_object (info
->region_node
);
479 /* An additional reference for the container */
481 acpi_ut_add_reference (obj_desc
->field
.region_obj
);
483 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD
,
484 "region_field: bit_off %X, Off %X, Gran %X, Region %p\n",
485 obj_desc
->field
.start_field_bit_offset
, obj_desc
->field
.base_byte_offset
,
486 obj_desc
->field
.access_byte_width
, obj_desc
->field
.region_obj
));
490 case ACPI_TYPE_LOCAL_BANK_FIELD
:
492 obj_desc
->bank_field
.value
= info
->bank_value
;
493 obj_desc
->bank_field
.region_obj
= acpi_ns_get_attached_object (
495 obj_desc
->bank_field
.bank_obj
= acpi_ns_get_attached_object (
496 info
->register_node
);
498 /* An additional reference for the attached objects */
500 acpi_ut_add_reference (obj_desc
->bank_field
.region_obj
);
501 acpi_ut_add_reference (obj_desc
->bank_field
.bank_obj
);
503 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD
,
504 "Bank Field: bit_off %X, Off %X, Gran %X, Region %p, bank_reg %p\n",
505 obj_desc
->bank_field
.start_field_bit_offset
,
506 obj_desc
->bank_field
.base_byte_offset
,
507 obj_desc
->field
.access_byte_width
,
508 obj_desc
->bank_field
.region_obj
,
509 obj_desc
->bank_field
.bank_obj
));
513 case ACPI_TYPE_LOCAL_INDEX_FIELD
:
515 obj_desc
->index_field
.index_obj
= acpi_ns_get_attached_object (
516 info
->register_node
);
517 obj_desc
->index_field
.data_obj
= acpi_ns_get_attached_object (
518 info
->data_register_node
);
519 obj_desc
->index_field
.value
= (u32
)
520 (info
->field_bit_position
/ ACPI_MUL_8 (
521 obj_desc
->field
.access_byte_width
));
523 if (!obj_desc
->index_field
.data_obj
|| !obj_desc
->index_field
.index_obj
) {
524 ACPI_REPORT_ERROR (("Null Index Object during field prep\n"));
525 acpi_ut_delete_object_desc (obj_desc
);
526 return_ACPI_STATUS (AE_AML_INTERNAL
);
529 /* An additional reference for the attached objects */
531 acpi_ut_add_reference (obj_desc
->index_field
.data_obj
);
532 acpi_ut_add_reference (obj_desc
->index_field
.index_obj
);
534 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD
,
535 "index_field: bit_off %X, Off %X, Value %X, Gran %X, Index %p, Data %p\n",
536 obj_desc
->index_field
.start_field_bit_offset
,
537 obj_desc
->index_field
.base_byte_offset
,
538 obj_desc
->index_field
.value
,
539 obj_desc
->field
.access_byte_width
,
540 obj_desc
->index_field
.index_obj
,
541 obj_desc
->index_field
.data_obj
));
545 /* No other types should get here */
550 * Store the constructed descriptor (obj_desc) into the parent Node,
551 * preserving the current type of that named_obj.
553 status
= acpi_ns_attach_object (info
->field_node
, obj_desc
,
554 acpi_ns_get_type (info
->field_node
));
556 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD
, "Set named_obj %p [%4.4s], obj_desc %p\n",
557 info
->field_node
, acpi_ut_get_node_name (info
->field_node
), obj_desc
));
559 /* Remove local reference to the object */
561 acpi_ut_remove_reference (obj_desc
);
562 return_ACPI_STATUS (status
);