1 /******************************************************************************
3 * Module Name: exprep - ACPI AML (p-code) execution - field prep utilities
5 *****************************************************************************/
8 * Copyright (C) 2000 - 2015, Intel Corp.
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
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.
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.
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
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40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41 * POSSIBILITY OF SUCH DAMAGES.
44 #include <acpi/acpi.h>
51 #define _COMPONENT ACPI_EXECUTER
52 ACPI_MODULE_NAME("exprep")
54 /* Local prototypes */
56 acpi_ex_decode_field_access(union acpi_operand_object
*obj_desc
,
57 u8 field_flags
, u32
* return_byte_alignment
);
59 #ifdef ACPI_UNDER_DEVELOPMENT
62 acpi_ex_generate_access(u32 field_bit_offset
,
63 u32 field_bit_length
, u32 region_length
);
65 /*******************************************************************************
67 * FUNCTION: acpi_ex_generate_access
69 * PARAMETERS: field_bit_offset - Start of field within parent region/buffer
70 * field_bit_length - Length of field in bits
71 * region_length - Length of parent in bytes
73 * RETURN: Field granularity (8, 16, 32 or 64) and
74 * byte_alignment (1, 2, 3, or 4)
76 * DESCRIPTION: Generate an optimal access width for fields defined with the
79 * NOTE: Need to have the region_length in order to check for boundary
80 * conditions (end-of-region). However, the region_length is a deferred
81 * operation. Therefore, to complete this implementation, the generation
82 * of this access width must be deferred until the region length has
85 ******************************************************************************/
88 acpi_ex_generate_access(u32 field_bit_offset
,
89 u32 field_bit_length
, u32 region_length
)
91 u32 field_byte_length
;
92 u32 field_byte_offset
;
93 u32 field_byte_end_offset
;
94 u32 access_byte_width
;
95 u32 field_start_offset
;
97 u32 minimum_access_width
= 0xFFFFFFFF;
98 u32 minimum_accesses
= 0xFFFFFFFF;
101 ACPI_FUNCTION_TRACE(ex_generate_access
);
103 /* Round Field start offset and length to "minimal" byte boundaries */
105 field_byte_offset
= ACPI_DIV_8(ACPI_ROUND_DOWN(field_bit_offset
, 8));
106 field_byte_end_offset
= ACPI_DIV_8(ACPI_ROUND_UP(field_bit_length
+
107 field_bit_offset
, 8));
108 field_byte_length
= field_byte_end_offset
- field_byte_offset
;
110 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
111 "Bit length %u, Bit offset %u\n",
112 field_bit_length
, field_bit_offset
));
114 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
115 "Byte Length %u, Byte Offset %u, End Offset %u\n",
116 field_byte_length
, field_byte_offset
,
117 field_byte_end_offset
));
120 * Iterative search for the maximum access width that is both aligned
121 * and does not go beyond the end of the region
123 * Start at byte_acc and work upwards to qword_acc max. (1,2,4,8 bytes)
125 for (access_byte_width
= 1; access_byte_width
<= 8;
126 access_byte_width
<<= 1) {
128 * 1) Round end offset up to next access boundary and make sure that
129 * this does not go beyond the end of the parent region.
130 * 2) When the Access width is greater than the field_byte_length, we
131 * are done. (This does not optimize for the perfectly aligned
134 if (ACPI_ROUND_UP(field_byte_end_offset
, access_byte_width
) <=
137 ACPI_ROUND_DOWN(field_byte_offset
,
142 ACPI_ROUND_UP((field_byte_length
+
147 accesses
= field_end_offset
- field_start_offset
;
149 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
150 "AccessWidth %u end is within region\n",
153 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
154 "Field Start %u, Field End %u -- requires %u accesses\n",
155 field_start_offset
, field_end_offset
,
158 /* Single access is optimal */
161 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
162 "Entire field can be accessed with one operation of size %u\n",
164 return_VALUE(access_byte_width
);
168 * Fits in the region, but requires more than one read/write.
169 * try the next wider access on next iteration
171 if (accesses
< minimum_accesses
) {
172 minimum_accesses
= accesses
;
173 minimum_access_width
= access_byte_width
;
176 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
177 "AccessWidth %u end is NOT within region\n",
179 if (access_byte_width
== 1) {
180 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
181 "Field goes beyond end-of-region!\n"));
183 /* Field does not fit in the region at all */
189 * This width goes beyond the end-of-region, back off to
192 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
193 "Backing off to previous optimal access width of %u\n",
194 minimum_access_width
));
195 return_VALUE(minimum_access_width
);
200 * Could not read/write field with one operation,
201 * just use max access width
203 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
204 "Cannot access field in one operation, using width 8\n"));
207 #endif /* ACPI_UNDER_DEVELOPMENT */
209 /*******************************************************************************
211 * FUNCTION: acpi_ex_decode_field_access
213 * PARAMETERS: obj_desc - Field object
214 * field_flags - Encoded fieldflags (contains access bits)
215 * return_byte_alignment - Where the byte alignment is returned
217 * RETURN: Field granularity (8, 16, 32 or 64) and
218 * byte_alignment (1, 2, 3, or 4)
220 * DESCRIPTION: Decode the access_type bits of a field definition.
222 ******************************************************************************/
225 acpi_ex_decode_field_access(union acpi_operand_object
*obj_desc
,
226 u8 field_flags
, u32
* return_byte_alignment
)
232 ACPI_FUNCTION_TRACE(ex_decode_field_access
);
234 access
= (field_flags
& AML_FIELD_ACCESS_TYPE_MASK
);
237 case AML_FIELD_ACCESS_ANY
:
239 #ifdef ACPI_UNDER_DEVELOPMENT
241 acpi_ex_generate_access(obj_desc
->common_field
.
242 start_field_bit_offset
,
243 obj_desc
->common_field
.bit_length
,
245 /* Temp until we pass region_length as parameter */
247 bit_length
= byte_alignment
* 8;
254 case AML_FIELD_ACCESS_BYTE
:
255 case AML_FIELD_ACCESS_BUFFER
: /* ACPI 2.0 (SMBus Buffer) */
261 case AML_FIELD_ACCESS_WORD
:
267 case AML_FIELD_ACCESS_DWORD
:
273 case AML_FIELD_ACCESS_QWORD
: /* ACPI 2.0 */
281 /* Invalid field access type */
283 ACPI_ERROR((AE_INFO
, "Unknown field access type 0x%X", access
));
287 if (obj_desc
->common
.type
== ACPI_TYPE_BUFFER_FIELD
) {
289 * buffer_field access can be on any byte boundary, so the
290 * byte_alignment is always 1 byte -- regardless of any byte_alignment
291 * implied by the field access type.
296 *return_byte_alignment
= byte_alignment
;
297 return_UINT32(bit_length
);
300 /*******************************************************************************
302 * FUNCTION: acpi_ex_prep_common_field_object
304 * PARAMETERS: obj_desc - The field object
305 * field_flags - Access, lock_rule, and update_rule.
306 * The format of a field_flag is described
307 * in the ACPI specification
308 * field_attribute - Special attributes (not used)
309 * field_bit_position - Field start position
310 * field_bit_length - Field length in number of bits
314 * DESCRIPTION: Initialize the areas of the field object that are common
315 * to the various types of fields. Note: This is very "sensitive"
316 * code because we are solving the general case for field
319 ******************************************************************************/
322 acpi_ex_prep_common_field_object(union acpi_operand_object
*obj_desc
,
325 u32 field_bit_position
, u32 field_bit_length
)
327 u32 access_bit_width
;
329 u32 nearest_byte_address
;
331 ACPI_FUNCTION_TRACE(ex_prep_common_field_object
);
334 * Note: the structure being initialized is the
335 * ACPI_COMMON_FIELD_INFO; No structure fields outside of the common
336 * area are initialized by this procedure.
338 obj_desc
->common_field
.field_flags
= field_flags
;
339 obj_desc
->common_field
.attribute
= field_attribute
;
340 obj_desc
->common_field
.bit_length
= field_bit_length
;
343 * Decode the access type so we can compute offsets. The access type gives
344 * two pieces of information - the width of each field access and the
345 * necessary byte_alignment (address granularity) of the access.
347 * For any_acc, the access_bit_width is the largest width that is both
348 * necessary and possible in an attempt to access the whole field in one
349 * I/O operation. However, for any_acc, the byte_alignment is always one
352 * For all Buffer Fields, the byte_alignment is always one byte.
354 * For all other access types (Byte, Word, Dword, Qword), the Bitwidth is
355 * the same (equivalent) as the byte_alignment.
357 access_bit_width
= acpi_ex_decode_field_access(obj_desc
, field_flags
,
359 if (!access_bit_width
) {
360 return_ACPI_STATUS(AE_AML_OPERAND_VALUE
);
363 /* Setup width (access granularity) fields (values are: 1, 2, 4, 8) */
365 obj_desc
->common_field
.access_byte_width
= (u8
)
366 ACPI_DIV_8(access_bit_width
);
369 * base_byte_offset is the address of the start of the field within the
370 * region. It is the byte address of the first *datum* (field-width data
371 * unit) of the field. (i.e., the first datum that contains at least the
372 * first *bit* of the field.)
374 * Note: byte_alignment is always either equal to the access_bit_width or 8
375 * (Byte access), and it defines the addressing granularity of the parent
378 nearest_byte_address
=
379 ACPI_ROUND_BITS_DOWN_TO_BYTES(field_bit_position
);
380 obj_desc
->common_field
.base_byte_offset
= (u32
)
381 ACPI_ROUND_DOWN(nearest_byte_address
, byte_alignment
);
384 * start_field_bit_offset is the offset of the first bit of the field within
387 obj_desc
->common_field
.start_field_bit_offset
= (u8
)
388 (field_bit_position
-
389 ACPI_MUL_8(obj_desc
->common_field
.base_byte_offset
));
391 return_ACPI_STATUS(AE_OK
);
394 /*******************************************************************************
396 * FUNCTION: acpi_ex_prep_field_value
398 * PARAMETERS: info - Contains all field creation info
402 * DESCRIPTION: Construct an object of type union acpi_operand_object with a
403 * subtype of def_field and connect it to the parent Node.
405 ******************************************************************************/
407 acpi_status
acpi_ex_prep_field_value(struct acpi_create_field_info
*info
)
409 union acpi_operand_object
*obj_desc
;
410 union acpi_operand_object
*second_desc
= NULL
;
412 u32 access_byte_width
;
415 ACPI_FUNCTION_TRACE(ex_prep_field_value
);
417 /* Parameter validation */
419 if (info
->field_type
!= ACPI_TYPE_LOCAL_INDEX_FIELD
) {
420 if (!info
->region_node
) {
421 ACPI_ERROR((AE_INFO
, "Null RegionNode"));
422 return_ACPI_STATUS(AE_AML_NO_OPERAND
);
425 type
= acpi_ns_get_type(info
->region_node
);
426 if (type
!= ACPI_TYPE_REGION
) {
428 "Needed Region, found type 0x%X (%s)", type
,
429 acpi_ut_get_type_name(type
)));
431 return_ACPI_STATUS(AE_AML_OPERAND_TYPE
);
435 /* Allocate a new field object */
437 obj_desc
= acpi_ut_create_internal_object(info
->field_type
);
439 return_ACPI_STATUS(AE_NO_MEMORY
);
442 /* Initialize areas of the object that are common to all fields */
444 obj_desc
->common_field
.node
= info
->field_node
;
445 status
= acpi_ex_prep_common_field_object(obj_desc
,
448 info
->field_bit_position
,
449 info
->field_bit_length
);
450 if (ACPI_FAILURE(status
)) {
451 acpi_ut_delete_object_desc(obj_desc
);
452 return_ACPI_STATUS(status
);
455 /* Initialize areas of the object that are specific to the field type */
457 switch (info
->field_type
) {
458 case ACPI_TYPE_LOCAL_REGION_FIELD
:
460 obj_desc
->field
.region_obj
=
461 acpi_ns_get_attached_object(info
->region_node
);
463 /* Fields specific to generic_serial_bus fields */
465 obj_desc
->field
.access_length
= info
->access_length
;
467 if (info
->connection_node
) {
468 second_desc
= info
->connection_node
->object
;
469 if (!(second_desc
->common
.flags
& AOPOBJ_DATA_VALID
)) {
471 acpi_ds_get_buffer_arguments(second_desc
);
472 if (ACPI_FAILURE(status
)) {
473 acpi_ut_delete_object_desc(obj_desc
);
474 return_ACPI_STATUS(status
);
478 obj_desc
->field
.resource_buffer
=
479 second_desc
->buffer
.pointer
;
480 obj_desc
->field
.resource_length
=
481 (u16
)second_desc
->buffer
.length
;
482 } else if (info
->resource_buffer
) {
483 obj_desc
->field
.resource_buffer
= info
->resource_buffer
;
484 obj_desc
->field
.resource_length
= info
->resource_length
;
487 obj_desc
->field
.pin_number_index
= info
->pin_number_index
;
489 /* Allow full data read from EC address space */
491 if ((obj_desc
->field
.region_obj
->region
.space_id
==
493 && (obj_desc
->common_field
.bit_length
> 8)) {
495 ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc
->common_field
.
498 /* Maximum byte width supported is 255 */
500 if (access_byte_width
< 256) {
501 obj_desc
->common_field
.access_byte_width
=
502 (u8
)access_byte_width
;
505 /* An additional reference for the container */
507 acpi_ut_add_reference(obj_desc
->field
.region_obj
);
509 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
510 "RegionField: BitOff %X, Off %X, Gran %X, Region %p\n",
511 obj_desc
->field
.start_field_bit_offset
,
512 obj_desc
->field
.base_byte_offset
,
513 obj_desc
->field
.access_byte_width
,
514 obj_desc
->field
.region_obj
));
517 case ACPI_TYPE_LOCAL_BANK_FIELD
:
519 obj_desc
->bank_field
.value
= info
->bank_value
;
520 obj_desc
->bank_field
.region_obj
=
521 acpi_ns_get_attached_object(info
->region_node
);
522 obj_desc
->bank_field
.bank_obj
=
523 acpi_ns_get_attached_object(info
->register_node
);
525 /* An additional reference for the attached objects */
527 acpi_ut_add_reference(obj_desc
->bank_field
.region_obj
);
528 acpi_ut_add_reference(obj_desc
->bank_field
.bank_obj
);
530 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
531 "Bank Field: BitOff %X, Off %X, Gran %X, Region %p, BankReg %p\n",
532 obj_desc
->bank_field
.start_field_bit_offset
,
533 obj_desc
->bank_field
.base_byte_offset
,
534 obj_desc
->field
.access_byte_width
,
535 obj_desc
->bank_field
.region_obj
,
536 obj_desc
->bank_field
.bank_obj
));
539 * Remember location in AML stream of the field unit
540 * opcode and operands -- since the bank_value
541 * operands must be evaluated.
543 second_desc
= obj_desc
->common
.next_object
;
544 second_desc
->extra
.aml_start
=
545 ACPI_CAST_PTR(union acpi_parse_object
,
546 info
->data_register_node
)->named
.data
;
547 second_desc
->extra
.aml_length
=
548 ACPI_CAST_PTR(union acpi_parse_object
,
549 info
->data_register_node
)->named
.length
;
553 case ACPI_TYPE_LOCAL_INDEX_FIELD
:
555 /* Get the Index and Data registers */
557 obj_desc
->index_field
.index_obj
=
558 acpi_ns_get_attached_object(info
->register_node
);
559 obj_desc
->index_field
.data_obj
=
560 acpi_ns_get_attached_object(info
->data_register_node
);
562 if (!obj_desc
->index_field
.data_obj
563 || !obj_desc
->index_field
.index_obj
) {
565 "Null Index Object during field prep"));
566 acpi_ut_delete_object_desc(obj_desc
);
567 return_ACPI_STATUS(AE_AML_INTERNAL
);
570 /* An additional reference for the attached objects */
572 acpi_ut_add_reference(obj_desc
->index_field
.data_obj
);
573 acpi_ut_add_reference(obj_desc
->index_field
.index_obj
);
576 * April 2006: Changed to match MS behavior
578 * The value written to the Index register is the byte offset of the
579 * target field in units of the granularity of the index_field
581 * Previously, the value was calculated as an index in terms of the
582 * width of the Data register, as below:
584 * obj_desc->index_field.Value = (u32)
585 * (Info->field_bit_position / ACPI_MUL_8 (
586 * obj_desc->Field.access_byte_width));
588 * February 2006: Tried value as a byte offset:
589 * obj_desc->index_field.Value = (u32)
590 * ACPI_DIV_8 (Info->field_bit_position);
592 obj_desc
->index_field
.value
=
593 (u32
) ACPI_ROUND_DOWN(ACPI_DIV_8(info
->field_bit_position
),
594 obj_desc
->index_field
.
597 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
598 "IndexField: BitOff %X, Off %X, Value %X, Gran %X, Index %p, Data %p\n",
599 obj_desc
->index_field
.start_field_bit_offset
,
600 obj_desc
->index_field
.base_byte_offset
,
601 obj_desc
->index_field
.value
,
602 obj_desc
->field
.access_byte_width
,
603 obj_desc
->index_field
.index_obj
,
604 obj_desc
->index_field
.data_obj
));
609 /* No other types should get here */
615 * Store the constructed descriptor (obj_desc) into the parent Node,
616 * preserving the current type of that named_obj.
618 status
= acpi_ns_attach_object(info
->field_node
, obj_desc
,
619 acpi_ns_get_type(info
->field_node
));
621 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
622 "Set NamedObj %p [%4.4s], ObjDesc %p\n",
624 acpi_ut_get_node_name(info
->field_node
), obj_desc
));
626 /* Remove local reference to the object */
628 acpi_ut_remove_reference(obj_desc
);
629 return_ACPI_STATUS(status
);