1 /******************************************************************************
3 * Module Name: exprep - ACPI AML field prep utilities
5 *****************************************************************************/
8 * Copyright (C) 2000 - 2016, 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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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.
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));
107 field_byte_end_offset
=
108 ACPI_DIV_8(ACPI_ROUND_UP(field_bit_length
+ field_bit_offset
, 8));
110 field_byte_length
= field_byte_end_offset
- field_byte_offset
;
112 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
113 "Bit length %u, Bit offset %u\n",
114 field_bit_length
, field_bit_offset
));
116 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
117 "Byte Length %u, Byte Offset %u, End Offset %u\n",
118 field_byte_length
, field_byte_offset
,
119 field_byte_end_offset
));
122 * Iterative search for the maximum access width that is both aligned
123 * and does not go beyond the end of the region
125 * Start at byte_acc and work upwards to qword_acc max. (1,2,4,8 bytes)
127 for (access_byte_width
= 1; access_byte_width
<= 8;
128 access_byte_width
<<= 1) {
130 * 1) Round end offset up to next access boundary and make sure that
131 * this does not go beyond the end of the parent region.
132 * 2) When the Access width is greater than the field_byte_length, we
133 * are done. (This does not optimize for the perfectly aligned
136 if (ACPI_ROUND_UP(field_byte_end_offset
, access_byte_width
) <=
139 ACPI_ROUND_DOWN(field_byte_offset
,
144 ACPI_ROUND_UP((field_byte_length
+
149 accesses
= field_end_offset
- field_start_offset
;
151 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
152 "AccessWidth %u end is within region\n",
155 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
156 "Field Start %u, Field End %u -- requires %u accesses\n",
157 field_start_offset
, field_end_offset
,
160 /* Single access is optimal */
163 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
164 "Entire field can be accessed "
165 "with one operation of size %u\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
;
179 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
180 "AccessWidth %u end is NOT within region\n",
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 %u\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"));
211 #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(union acpi_operand_object
*obj_desc
,
230 u8 field_flags
, u32
* return_byte_alignment
)
236 ACPI_FUNCTION_TRACE(ex_decode_field_access
);
238 access
= (field_flags
& AML_FIELD_ACCESS_TYPE_MASK
);
241 case AML_FIELD_ACCESS_ANY
:
243 #ifdef ACPI_UNDER_DEVELOPMENT
245 acpi_ex_generate_access(obj_desc
->common_field
.
246 start_field_bit_offset
,
247 obj_desc
->common_field
.bit_length
,
249 /* Temp until we pass region_length as parameter */
251 bit_length
= byte_alignment
* 8;
258 case AML_FIELD_ACCESS_BYTE
:
259 case AML_FIELD_ACCESS_BUFFER
: /* ACPI 2.0 (SMBus Buffer) */
265 case AML_FIELD_ACCESS_WORD
:
271 case AML_FIELD_ACCESS_DWORD
:
277 case AML_FIELD_ACCESS_QWORD
: /* ACPI 2.0 */
285 /* Invalid field access type */
287 ACPI_ERROR((AE_INFO
, "Unknown field access type 0x%X", access
));
292 if (obj_desc
->common
.type
== ACPI_TYPE_BUFFER_FIELD
) {
294 * buffer_field access can be on any byte boundary, so the
295 * byte_alignment is always 1 byte -- regardless of any byte_alignment
296 * implied by the field access type.
301 *return_byte_alignment
= byte_alignment
;
302 return_UINT32(bit_length
);
305 /*******************************************************************************
307 * FUNCTION: acpi_ex_prep_common_field_object
309 * PARAMETERS: obj_desc - The field object
310 * field_flags - Access, lock_rule, and update_rule.
311 * The format of a field_flag is described
312 * in the ACPI specification
313 * field_attribute - Special attributes (not used)
314 * field_bit_position - Field start position
315 * field_bit_length - Field length in number of bits
319 * DESCRIPTION: Initialize the areas of the field object that are common
320 * to the various types of fields. Note: This is very "sensitive"
321 * code because we are solving the general case for field
324 ******************************************************************************/
327 acpi_ex_prep_common_field_object(union acpi_operand_object
*obj_desc
,
330 u32 field_bit_position
, u32 field_bit_length
)
332 u32 access_bit_width
;
334 u32 nearest_byte_address
;
336 ACPI_FUNCTION_TRACE(ex_prep_common_field_object
);
339 * Note: the structure being initialized is the
340 * ACPI_COMMON_FIELD_INFO; No structure fields outside of the common
341 * area are initialized by this procedure.
343 obj_desc
->common_field
.field_flags
= field_flags
;
344 obj_desc
->common_field
.attribute
= field_attribute
;
345 obj_desc
->common_field
.bit_length
= field_bit_length
;
348 * Decode the access type so we can compute offsets. The access type gives
349 * two pieces of information - the width of each field access and the
350 * necessary byte_alignment (address granularity) of the access.
352 * For any_acc, the access_bit_width is the largest width that is both
353 * necessary and possible in an attempt to access the whole field in one
354 * I/O operation. However, for any_acc, the byte_alignment is always one
357 * For all Buffer Fields, the byte_alignment is always one byte.
359 * For all other access types (Byte, Word, Dword, Qword), the Bitwidth is
360 * the same (equivalent) as the byte_alignment.
363 acpi_ex_decode_field_access(obj_desc
, field_flags
, &byte_alignment
);
364 if (!access_bit_width
) {
365 return_ACPI_STATUS(AE_AML_OPERAND_VALUE
);
368 /* Setup width (access granularity) fields (values are: 1, 2, 4, 8) */
370 obj_desc
->common_field
.access_byte_width
= (u8
)
371 ACPI_DIV_8(access_bit_width
);
374 * base_byte_offset is the address of the start of the field within the
375 * region. It is the byte address of the first *datum* (field-width data
376 * unit) of the field. (i.e., the first datum that contains at least the
377 * first *bit* of the field.)
379 * Note: byte_alignment is always either equal to the access_bit_width or 8
380 * (Byte access), and it defines the addressing granularity of the parent
383 nearest_byte_address
=
384 ACPI_ROUND_BITS_DOWN_TO_BYTES(field_bit_position
);
385 obj_desc
->common_field
.base_byte_offset
= (u32
)
386 ACPI_ROUND_DOWN(nearest_byte_address
, byte_alignment
);
389 * start_field_bit_offset is the offset of the first bit of the field within
392 obj_desc
->common_field
.start_field_bit_offset
= (u8
)
393 (field_bit_position
-
394 ACPI_MUL_8(obj_desc
->common_field
.base_byte_offset
));
396 return_ACPI_STATUS(AE_OK
);
399 /*******************************************************************************
401 * FUNCTION: acpi_ex_prep_field_value
403 * PARAMETERS: info - Contains all field creation info
407 * DESCRIPTION: Construct an object of type union acpi_operand_object with a
408 * subtype of def_field and connect it to the parent Node.
410 ******************************************************************************/
412 acpi_status
acpi_ex_prep_field_value(struct acpi_create_field_info
*info
)
414 union acpi_operand_object
*obj_desc
;
415 union acpi_operand_object
*second_desc
= NULL
;
417 u32 access_byte_width
;
420 ACPI_FUNCTION_TRACE(ex_prep_field_value
);
422 /* Parameter validation */
424 if (info
->field_type
!= ACPI_TYPE_LOCAL_INDEX_FIELD
) {
425 if (!info
->region_node
) {
426 ACPI_ERROR((AE_INFO
, "Null RegionNode"));
427 return_ACPI_STATUS(AE_AML_NO_OPERAND
);
430 type
= acpi_ns_get_type(info
->region_node
);
431 if (type
!= ACPI_TYPE_REGION
) {
433 "Needed Region, found type 0x%X (%s)", type
,
434 acpi_ut_get_type_name(type
)));
436 return_ACPI_STATUS(AE_AML_OPERAND_TYPE
);
440 /* Allocate a new field object */
442 obj_desc
= acpi_ut_create_internal_object(info
->field_type
);
444 return_ACPI_STATUS(AE_NO_MEMORY
);
447 /* Initialize areas of the object that are common to all fields */
449 obj_desc
->common_field
.node
= info
->field_node
;
450 status
= acpi_ex_prep_common_field_object(obj_desc
,
453 info
->field_bit_position
,
454 info
->field_bit_length
);
455 if (ACPI_FAILURE(status
)) {
456 acpi_ut_delete_object_desc(obj_desc
);
457 return_ACPI_STATUS(status
);
460 /* Initialize areas of the object that are specific to the field type */
462 switch (info
->field_type
) {
463 case ACPI_TYPE_LOCAL_REGION_FIELD
:
465 obj_desc
->field
.region_obj
=
466 acpi_ns_get_attached_object(info
->region_node
);
468 /* Fields specific to generic_serial_bus fields */
470 obj_desc
->field
.access_length
= info
->access_length
;
472 if (info
->connection_node
) {
473 second_desc
= info
->connection_node
->object
;
474 if (!(second_desc
->common
.flags
& AOPOBJ_DATA_VALID
)) {
476 acpi_ds_get_buffer_arguments(second_desc
);
477 if (ACPI_FAILURE(status
)) {
478 acpi_ut_delete_object_desc(obj_desc
);
479 return_ACPI_STATUS(status
);
483 obj_desc
->field
.resource_buffer
=
484 second_desc
->buffer
.pointer
;
485 obj_desc
->field
.resource_length
=
486 (u16
)second_desc
->buffer
.length
;
487 } else if (info
->resource_buffer
) {
488 obj_desc
->field
.resource_buffer
= info
->resource_buffer
;
489 obj_desc
->field
.resource_length
= info
->resource_length
;
492 obj_desc
->field
.pin_number_index
= info
->pin_number_index
;
494 /* Allow full data read from EC address space */
496 if ((obj_desc
->field
.region_obj
->region
.space_id
==
498 && (obj_desc
->common_field
.bit_length
> 8)) {
500 ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc
->common_field
.
503 /* Maximum byte width supported is 255 */
505 if (access_byte_width
< 256) {
506 obj_desc
->common_field
.access_byte_width
=
507 (u8
)access_byte_width
;
510 /* An additional reference for the container */
512 acpi_ut_add_reference(obj_desc
->field
.region_obj
);
514 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
515 "RegionField: BitOff %X, Off %X, Gran %X, Region %p\n",
516 obj_desc
->field
.start_field_bit_offset
,
517 obj_desc
->field
.base_byte_offset
,
518 obj_desc
->field
.access_byte_width
,
519 obj_desc
->field
.region_obj
));
522 case ACPI_TYPE_LOCAL_BANK_FIELD
:
524 obj_desc
->bank_field
.value
= info
->bank_value
;
525 obj_desc
->bank_field
.region_obj
=
526 acpi_ns_get_attached_object(info
->region_node
);
527 obj_desc
->bank_field
.bank_obj
=
528 acpi_ns_get_attached_object(info
->register_node
);
530 /* An additional reference for the attached objects */
532 acpi_ut_add_reference(obj_desc
->bank_field
.region_obj
);
533 acpi_ut_add_reference(obj_desc
->bank_field
.bank_obj
);
535 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
536 "Bank Field: BitOff %X, Off %X, Gran %X, Region %p, BankReg %p\n",
537 obj_desc
->bank_field
.start_field_bit_offset
,
538 obj_desc
->bank_field
.base_byte_offset
,
539 obj_desc
->field
.access_byte_width
,
540 obj_desc
->bank_field
.region_obj
,
541 obj_desc
->bank_field
.bank_obj
));
544 * Remember location in AML stream of the field unit
545 * opcode and operands -- since the bank_value
546 * operands must be evaluated.
548 second_desc
= obj_desc
->common
.next_object
;
549 second_desc
->extra
.aml_start
=
550 ACPI_CAST_PTR(union acpi_parse_object
,
551 info
->data_register_node
)->named
.data
;
552 second_desc
->extra
.aml_length
=
553 ACPI_CAST_PTR(union acpi_parse_object
,
554 info
->data_register_node
)->named
.length
;
558 case ACPI_TYPE_LOCAL_INDEX_FIELD
:
560 /* Get the Index and Data registers */
562 obj_desc
->index_field
.index_obj
=
563 acpi_ns_get_attached_object(info
->register_node
);
564 obj_desc
->index_field
.data_obj
=
565 acpi_ns_get_attached_object(info
->data_register_node
);
567 if (!obj_desc
->index_field
.data_obj
568 || !obj_desc
->index_field
.index_obj
) {
570 "Null Index Object during field prep"));
571 acpi_ut_delete_object_desc(obj_desc
);
572 return_ACPI_STATUS(AE_AML_INTERNAL
);
575 /* An additional reference for the attached objects */
577 acpi_ut_add_reference(obj_desc
->index_field
.data_obj
);
578 acpi_ut_add_reference(obj_desc
->index_field
.index_obj
);
581 * April 2006: Changed to match MS behavior
583 * The value written to the Index register is the byte offset of the
584 * target field in units of the granularity of the index_field
586 * Previously, the value was calculated as an index in terms of the
587 * width of the Data register, as below:
589 * obj_desc->index_field.Value = (u32)
590 * (Info->field_bit_position / ACPI_MUL_8 (
591 * obj_desc->Field.access_byte_width));
593 * February 2006: Tried value as a byte offset:
594 * obj_desc->index_field.Value = (u32)
595 * ACPI_DIV_8 (Info->field_bit_position);
597 obj_desc
->index_field
.value
=
598 (u32
) ACPI_ROUND_DOWN(ACPI_DIV_8(info
->field_bit_position
),
599 obj_desc
->index_field
.
602 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
603 "IndexField: BitOff %X, Off %X, Value %X, "
604 "Gran %X, Index %p, Data %p\n",
605 obj_desc
->index_field
.start_field_bit_offset
,
606 obj_desc
->index_field
.base_byte_offset
,
607 obj_desc
->index_field
.value
,
608 obj_desc
->field
.access_byte_width
,
609 obj_desc
->index_field
.index_obj
,
610 obj_desc
->index_field
.data_obj
));
615 /* No other types should get here */
621 * Store the constructed descriptor (obj_desc) into the parent Node,
622 * preserving the current type of that named_obj.
625 acpi_ns_attach_object(info
->field_node
, obj_desc
,
626 acpi_ns_get_type(info
->field_node
));
628 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD
,
629 "Set NamedObj %p [%4.4s], ObjDesc %p\n",
631 acpi_ut_get_node_name(info
->field_node
), obj_desc
));
633 /* Remove local reference to the object */
635 acpi_ut_remove_reference(obj_desc
);
636 return_ACPI_STATUS(status
);