Revert "ARM: tegra: tegratab: dummy change"
[linux-2.6.git] / drivers / acpi / acpica / exprep.c
1
2 /******************************************************************************
3  *
4  * Module Name: exprep - ACPI AML (p-code) execution - field prep utilities
5  *
6  *****************************************************************************/
7
8 /*
9  * Copyright (C) 2000 - 2012, Intel Corp.
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 "accommon.h"
47 #include "acinterp.h"
48 #include "amlcode.h"
49 #include "acnamesp.h"
50 #include "acdispat.h"
51
52 #define _COMPONENT          ACPI_EXECUTER
53 ACPI_MODULE_NAME("exprep")
54
55 /* Local prototypes */
56 static u32
57 acpi_ex_decode_field_access(union acpi_operand_object *obj_desc,
58                             u8 field_flags, u32 * return_byte_alignment);
59
60 #ifdef ACPI_UNDER_DEVELOPMENT
61
62 static u32
63 acpi_ex_generate_access(u32 field_bit_offset,
64                         u32 field_bit_length, u32 region_length);
65
66 /*******************************************************************************
67  *
68  * FUNCTION:    acpi_ex_generate_access
69  *
70  * PARAMETERS:  field_bit_offset    - Start of field within parent region/buffer
71  *              field_bit_length    - Length of field in bits
72  *              region_length       - Length of parent in bytes
73  *
74  * RETURN:      Field granularity (8, 16, 32 or 64) and
75  *              byte_alignment (1, 2, 3, or 4)
76  *
77  * DESCRIPTION: Generate an optimal access width for fields defined with the
78  *              any_acc keyword.
79  *
80  * NOTE: Need to have the region_length in order to check for boundary
81  *       conditions (end-of-region).  However, the region_length is a deferred
82  *       operation.  Therefore, to complete this implementation, the generation
83  *       of this access width must be deferred until the region length has
84  *       been evaluated.
85  *
86  ******************************************************************************/
87
88 static u32
89 acpi_ex_generate_access(u32 field_bit_offset,
90                         u32 field_bit_length, u32 region_length)
91 {
92         u32 field_byte_length;
93         u32 field_byte_offset;
94         u32 field_byte_end_offset;
95         u32 access_byte_width;
96         u32 field_start_offset;
97         u32 field_end_offset;
98         u32 minimum_access_width = 0xFFFFFFFF;
99         u32 minimum_accesses = 0xFFFFFFFF;
100         u32 accesses;
101
102         ACPI_FUNCTION_TRACE(ex_generate_access);
103
104         /* Round Field start offset and length to "minimal" byte boundaries */
105
106         field_byte_offset = ACPI_DIV_8(ACPI_ROUND_DOWN(field_bit_offset, 8));
107         field_byte_end_offset = ACPI_DIV_8(ACPI_ROUND_UP(field_bit_length +
108                                                          field_bit_offset, 8));
109         field_byte_length = field_byte_end_offset - field_byte_offset;
110
111         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
112                           "Bit length %u, Bit offset %u\n",
113                           field_bit_length, field_bit_offset));
114
115         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
116                           "Byte Length %u, Byte Offset %u, End Offset %u\n",
117                           field_byte_length, field_byte_offset,
118                           field_byte_end_offset));
119
120         /*
121          * Iterative search for the maximum access width that is both aligned
122          * and does not go beyond the end of the region
123          *
124          * Start at byte_acc and work upwards to qword_acc max. (1,2,4,8 bytes)
125          */
126         for (access_byte_width = 1; access_byte_width <= 8;
127              access_byte_width <<= 1) {
128                 /*
129                  * 1) Round end offset up to next access boundary and make sure that
130                  *    this does not go beyond the end of the parent region.
131                  * 2) When the Access width is greater than the field_byte_length, we
132                  *    are done. (This does not optimize for the perfectly aligned
133                  *    case yet).
134                  */
135                 if (ACPI_ROUND_UP(field_byte_end_offset, access_byte_width) <=
136                     region_length) {
137                         field_start_offset =
138                             ACPI_ROUND_DOWN(field_byte_offset,
139                                             access_byte_width) /
140                             access_byte_width;
141
142                         field_end_offset =
143                             ACPI_ROUND_UP((field_byte_length +
144                                            field_byte_offset),
145                                           access_byte_width) /
146                             access_byte_width;
147
148                         accesses = field_end_offset - field_start_offset;
149
150                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
151                                           "AccessWidth %u end is within region\n",
152                                           access_byte_width));
153
154                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
155                                           "Field Start %u, Field End %u -- requires %u accesses\n",
156                                           field_start_offset, field_end_offset,
157                                           accesses));
158
159                         /* Single access is optimal */
160
161                         if (accesses <= 1) {
162                                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
163                                                   "Entire field can be accessed with one operation of size %u\n",
164                                                   access_byte_width));
165                                 return_VALUE(access_byte_width);
166                         }
167
168                         /*
169                          * Fits in the region, but requires more than one read/write.
170                          * try the next wider access on next iteration
171                          */
172                         if (accesses < minimum_accesses) {
173                                 minimum_accesses = accesses;
174                                 minimum_access_width = access_byte_width;
175                         }
176                 } else {
177                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
178                                           "AccessWidth %u end is NOT within region\n",
179                                           access_byte_width));
180                         if (access_byte_width == 1) {
181                                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
182                                                   "Field goes beyond end-of-region!\n"));
183
184                                 /* Field does not fit in the region at all */
185
186                                 return_VALUE(0);
187                         }
188
189                         /*
190                          * This width goes beyond the end-of-region, back off to
191                          * previous access
192                          */
193                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
194                                           "Backing off to previous optimal access width of %u\n",
195                                           minimum_access_width));
196                         return_VALUE(minimum_access_width);
197                 }
198         }
199
200         /*
201          * Could not read/write field with one operation,
202          * just use max access width
203          */
204         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
205                           "Cannot access field in one operation, using width 8\n"));
206         return_VALUE(8);
207 }
208 #endif                          /* ACPI_UNDER_DEVELOPMENT */
209
210 /*******************************************************************************
211  *
212  * FUNCTION:    acpi_ex_decode_field_access
213  *
214  * PARAMETERS:  obj_desc            - Field object
215  *              field_flags         - Encoded fieldflags (contains access bits)
216  *              return_byte_alignment - Where the byte alignment is returned
217  *
218  * RETURN:      Field granularity (8, 16, 32 or 64) and
219  *              byte_alignment (1, 2, 3, or 4)
220  *
221  * DESCRIPTION: Decode the access_type bits of a field definition.
222  *
223  ******************************************************************************/
224
225 static u32
226 acpi_ex_decode_field_access(union acpi_operand_object *obj_desc,
227                             u8 field_flags, u32 * return_byte_alignment)
228 {
229         u32 access;
230         u32 byte_alignment;
231         u32 bit_length;
232
233         ACPI_FUNCTION_TRACE(ex_decode_field_access);
234
235         access = (field_flags & AML_FIELD_ACCESS_TYPE_MASK);
236
237         switch (access) {
238         case AML_FIELD_ACCESS_ANY:
239
240 #ifdef ACPI_UNDER_DEVELOPMENT
241                 byte_alignment =
242                     acpi_ex_generate_access(obj_desc->common_field.
243                                             start_field_bit_offset,
244                                             obj_desc->common_field.bit_length,
245                                             0xFFFFFFFF
246                                             /* Temp until we pass region_length as parameter */
247                     );
248                 bit_length = byte_alignment * 8;
249 #endif
250
251                 byte_alignment = 1;
252                 bit_length = 8;
253                 break;
254
255         case AML_FIELD_ACCESS_BYTE:
256         case AML_FIELD_ACCESS_BUFFER:   /* ACPI 2.0 (SMBus Buffer) */
257                 byte_alignment = 1;
258                 bit_length = 8;
259                 break;
260
261         case AML_FIELD_ACCESS_WORD:
262                 byte_alignment = 2;
263                 bit_length = 16;
264                 break;
265
266         case AML_FIELD_ACCESS_DWORD:
267                 byte_alignment = 4;
268                 bit_length = 32;
269                 break;
270
271         case AML_FIELD_ACCESS_QWORD:    /* ACPI 2.0 */
272                 byte_alignment = 8;
273                 bit_length = 64;
274                 break;
275
276         default:
277                 /* Invalid field access type */
278
279                 ACPI_ERROR((AE_INFO, "Unknown field access type 0x%X", access));
280                 return_UINT32(0);
281         }
282
283         if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
284                 /*
285                  * buffer_field access can be on any byte boundary, so the
286                  * byte_alignment is always 1 byte -- regardless of any byte_alignment
287                  * implied by the field access type.
288                  */
289                 byte_alignment = 1;
290         }
291
292         *return_byte_alignment = byte_alignment;
293         return_UINT32(bit_length);
294 }
295
296 /*******************************************************************************
297  *
298  * FUNCTION:    acpi_ex_prep_common_field_object
299  *
300  * PARAMETERS:  obj_desc            - The field object
301  *              field_flags         - Access, lock_rule, and update_rule.
302  *                                    The format of a field_flag is described
303  *                                    in the ACPI specification
304  *              field_attribute     - Special attributes (not used)
305  *              field_bit_position  - Field start position
306  *              field_bit_length    - Field length in number of bits
307  *
308  * RETURN:      Status
309  *
310  * DESCRIPTION: Initialize the areas of the field object that are common
311  *              to the various types of fields.  Note: This is very "sensitive"
312  *              code because we are solving the general case for field
313  *              alignment.
314  *
315  ******************************************************************************/
316
317 acpi_status
318 acpi_ex_prep_common_field_object(union acpi_operand_object *obj_desc,
319                                  u8 field_flags,
320                                  u8 field_attribute,
321                                  u32 field_bit_position, u32 field_bit_length)
322 {
323         u32 access_bit_width;
324         u32 byte_alignment;
325         u32 nearest_byte_address;
326
327         ACPI_FUNCTION_TRACE(ex_prep_common_field_object);
328
329         /*
330          * Note: the structure being initialized is the
331          * ACPI_COMMON_FIELD_INFO;  No structure fields outside of the common
332          * area are initialized by this procedure.
333          */
334         obj_desc->common_field.field_flags = field_flags;
335         obj_desc->common_field.attribute = field_attribute;
336         obj_desc->common_field.bit_length = field_bit_length;
337
338         /*
339          * Decode the access type so we can compute offsets.  The access type gives
340          * two pieces of information - the width of each field access and the
341          * necessary byte_alignment (address granularity) of the access.
342          *
343          * For any_acc, the access_bit_width is the largest width that is both
344          * necessary and possible in an attempt to access the whole field in one
345          * I/O operation.  However, for any_acc, the byte_alignment is always one
346          * byte.
347          *
348          * For all Buffer Fields, the byte_alignment is always one byte.
349          *
350          * For all other access types (Byte, Word, Dword, Qword), the Bitwidth is
351          * the same (equivalent) as the byte_alignment.
352          */
353         access_bit_width = acpi_ex_decode_field_access(obj_desc, field_flags,
354                                                        &byte_alignment);
355         if (!access_bit_width) {
356                 return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
357         }
358
359         /* Setup width (access granularity) fields (values are: 1, 2, 4, 8) */
360
361         obj_desc->common_field.access_byte_width = (u8)
362             ACPI_DIV_8(access_bit_width);
363
364         /*
365          * base_byte_offset is the address of the start of the field within the
366          * region.  It is the byte address of the first *datum* (field-width data
367          * unit) of the field. (i.e., the first datum that contains at least the
368          * first *bit* of the field.)
369          *
370          * Note: byte_alignment is always either equal to the access_bit_width or 8
371          * (Byte access), and it defines the addressing granularity of the parent
372          * region or buffer.
373          */
374         nearest_byte_address =
375             ACPI_ROUND_BITS_DOWN_TO_BYTES(field_bit_position);
376         obj_desc->common_field.base_byte_offset = (u32)
377             ACPI_ROUND_DOWN(nearest_byte_address, byte_alignment);
378
379         /*
380          * start_field_bit_offset is the offset of the first bit of the field within
381          * a field datum.
382          */
383         obj_desc->common_field.start_field_bit_offset = (u8)
384             (field_bit_position -
385              ACPI_MUL_8(obj_desc->common_field.base_byte_offset));
386
387         return_ACPI_STATUS(AE_OK);
388 }
389
390 /*******************************************************************************
391  *
392  * FUNCTION:    acpi_ex_prep_field_value
393  *
394  * PARAMETERS:  Info    - Contains all field creation info
395  *
396  * RETURN:      Status
397  *
398  * DESCRIPTION: Construct a union acpi_operand_object of type def_field and
399  *              connect it to the parent Node.
400  *
401  ******************************************************************************/
402
403 acpi_status acpi_ex_prep_field_value(struct acpi_create_field_info *info)
404 {
405         union acpi_operand_object *obj_desc;
406         union acpi_operand_object *second_desc = NULL;
407         acpi_status status;
408         u32 access_byte_width;
409         u32 type;
410
411         ACPI_FUNCTION_TRACE(ex_prep_field_value);
412
413         /* Parameter validation */
414
415         if (info->field_type != ACPI_TYPE_LOCAL_INDEX_FIELD) {
416                 if (!info->region_node) {
417                         ACPI_ERROR((AE_INFO, "Null RegionNode"));
418                         return_ACPI_STATUS(AE_AML_NO_OPERAND);
419                 }
420
421                 type = acpi_ns_get_type(info->region_node);
422                 if (type != ACPI_TYPE_REGION) {
423                         ACPI_ERROR((AE_INFO,
424                                     "Needed Region, found type 0x%X (%s)", type,
425                                     acpi_ut_get_type_name(type)));
426
427                         return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
428                 }
429         }
430
431         /* Allocate a new field object */
432
433         obj_desc = acpi_ut_create_internal_object(info->field_type);
434         if (!obj_desc) {
435                 return_ACPI_STATUS(AE_NO_MEMORY);
436         }
437
438         /* Initialize areas of the object that are common to all fields */
439
440         obj_desc->common_field.node = info->field_node;
441         status = acpi_ex_prep_common_field_object(obj_desc,
442                                                   info->field_flags,
443                                                   info->attribute,
444                                                   info->field_bit_position,
445                                                   info->field_bit_length);
446         if (ACPI_FAILURE(status)) {
447                 acpi_ut_delete_object_desc(obj_desc);
448                 return_ACPI_STATUS(status);
449         }
450
451         /* Initialize areas of the object that are specific to the field type */
452
453         switch (info->field_type) {
454         case ACPI_TYPE_LOCAL_REGION_FIELD:
455
456                 obj_desc->field.region_obj =
457                     acpi_ns_get_attached_object(info->region_node);
458
459                 /* Fields specific to generic_serial_bus fields */
460
461                 obj_desc->field.access_length = info->access_length;
462
463                 if (info->connection_node) {
464                         second_desc = info->connection_node->object;
465                         if (!(second_desc->common.flags & AOPOBJ_DATA_VALID)) {
466                                 status =
467                                     acpi_ds_get_buffer_arguments(second_desc);
468                                 if (ACPI_FAILURE(status)) {
469                                         acpi_ut_delete_object_desc(obj_desc);
470                                         return_ACPI_STATUS(status);
471                                 }
472                         }
473
474                         obj_desc->field.resource_buffer =
475                             second_desc->buffer.pointer;
476                         obj_desc->field.resource_length =
477                             (u16)second_desc->buffer.length;
478                 } else if (info->resource_buffer) {
479                         obj_desc->field.resource_buffer = info->resource_buffer;
480                         obj_desc->field.resource_length = info->resource_length;
481                 }
482
483                 /* Allow full data read from EC address space */
484
485                 if ((obj_desc->field.region_obj->region.space_id ==
486                      ACPI_ADR_SPACE_EC)
487                     && (obj_desc->common_field.bit_length > 8)) {
488                         access_byte_width =
489                             ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.
490                                                         bit_length);
491
492                         /* Maximum byte width supported is 255 */
493
494                         if (access_byte_width < 256) {
495                                 obj_desc->common_field.access_byte_width =
496                                     (u8)access_byte_width;
497                         }
498                 }
499                 /* An additional reference for the container */
500
501                 acpi_ut_add_reference(obj_desc->field.region_obj);
502
503                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
504                                   "RegionField: BitOff %X, Off %X, Gran %X, Region %p\n",
505                                   obj_desc->field.start_field_bit_offset,
506                                   obj_desc->field.base_byte_offset,
507                                   obj_desc->field.access_byte_width,
508                                   obj_desc->field.region_obj));
509                 break;
510
511         case ACPI_TYPE_LOCAL_BANK_FIELD:
512
513                 obj_desc->bank_field.value = info->bank_value;
514                 obj_desc->bank_field.region_obj =
515                     acpi_ns_get_attached_object(info->region_node);
516                 obj_desc->bank_field.bank_obj =
517                     acpi_ns_get_attached_object(info->register_node);
518
519                 /* An additional reference for the attached objects */
520
521                 acpi_ut_add_reference(obj_desc->bank_field.region_obj);
522                 acpi_ut_add_reference(obj_desc->bank_field.bank_obj);
523
524                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
525                                   "Bank Field: BitOff %X, Off %X, Gran %X, Region %p, BankReg %p\n",
526                                   obj_desc->bank_field.start_field_bit_offset,
527                                   obj_desc->bank_field.base_byte_offset,
528                                   obj_desc->field.access_byte_width,
529                                   obj_desc->bank_field.region_obj,
530                                   obj_desc->bank_field.bank_obj));
531
532                 /*
533                  * Remember location in AML stream of the field unit
534                  * opcode and operands -- since the bank_value
535                  * operands must be evaluated.
536                  */
537                 second_desc = obj_desc->common.next_object;
538                 second_desc->extra.aml_start =
539                     ACPI_CAST_PTR(union acpi_parse_object,
540                                   info->data_register_node)->named.data;
541                 second_desc->extra.aml_length =
542                     ACPI_CAST_PTR(union acpi_parse_object,
543                                   info->data_register_node)->named.length;
544
545                 break;
546
547         case ACPI_TYPE_LOCAL_INDEX_FIELD:
548
549                 /* Get the Index and Data registers */
550
551                 obj_desc->index_field.index_obj =
552                     acpi_ns_get_attached_object(info->register_node);
553                 obj_desc->index_field.data_obj =
554                     acpi_ns_get_attached_object(info->data_register_node);
555
556                 if (!obj_desc->index_field.data_obj
557                     || !obj_desc->index_field.index_obj) {
558                         ACPI_ERROR((AE_INFO,
559                                     "Null Index Object during field prep"));
560                         acpi_ut_delete_object_desc(obj_desc);
561                         return_ACPI_STATUS(AE_AML_INTERNAL);
562                 }
563
564                 /* An additional reference for the attached objects */
565
566                 acpi_ut_add_reference(obj_desc->index_field.data_obj);
567                 acpi_ut_add_reference(obj_desc->index_field.index_obj);
568
569                 /*
570                  * April 2006: Changed to match MS behavior
571                  *
572                  * The value written to the Index register is the byte offset of the
573                  * target field in units of the granularity of the index_field
574                  *
575                  * Previously, the value was calculated as an index in terms of the
576                  * width of the Data register, as below:
577                  *
578                  *      obj_desc->index_field.Value = (u32)
579                  *          (Info->field_bit_position / ACPI_MUL_8 (
580                  *              obj_desc->Field.access_byte_width));
581                  *
582                  * February 2006: Tried value as a byte offset:
583                  *      obj_desc->index_field.Value = (u32)
584                  *          ACPI_DIV_8 (Info->field_bit_position);
585                  */
586                 obj_desc->index_field.value =
587                     (u32) ACPI_ROUND_DOWN(ACPI_DIV_8(info->field_bit_position),
588                                           obj_desc->index_field.
589                                           access_byte_width);
590
591                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
592                                   "IndexField: BitOff %X, Off %X, Value %X, Gran %X, Index %p, Data %p\n",
593                                   obj_desc->index_field.start_field_bit_offset,
594                                   obj_desc->index_field.base_byte_offset,
595                                   obj_desc->index_field.value,
596                                   obj_desc->field.access_byte_width,
597                                   obj_desc->index_field.index_obj,
598                                   obj_desc->index_field.data_obj));
599                 break;
600
601         default:
602                 /* No other types should get here */
603                 break;
604         }
605
606         /*
607          * Store the constructed descriptor (obj_desc) into the parent Node,
608          * preserving the current type of that named_obj.
609          */
610         status = acpi_ns_attach_object(info->field_node, obj_desc,
611                                        acpi_ns_get_type(info->field_node));
612
613         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
614                           "Set NamedObj %p [%4.4s], ObjDesc %p\n",
615                           info->field_node,
616                           acpi_ut_get_node_name(info->field_node), obj_desc));
617
618         /* Remove local reference to the object */
619
620         acpi_ut_remove_reference(obj_desc);
621         return_ACPI_STATUS(status);
622 }