Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[sfrench/cifs-2.6.git] / drivers / acpi / acpica / exprep.c
1 /******************************************************************************
2  *
3  * Module Name: exprep - ACPI AML field prep utilities
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2018, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
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.
25  *
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.
29  *
30  * NO WARRANTY
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
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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.
42  */
43
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acinterp.h"
47 #include "amlcode.h"
48 #include "acnamesp.h"
49 #include "acdispat.h"
50
51 #define _COMPONENT          ACPI_EXECUTER
52 ACPI_MODULE_NAME("exprep")
53
54 /* Local prototypes */
55 static u32
56 acpi_ex_decode_field_access(union acpi_operand_object *obj_desc,
57                             u8 field_flags, u32 * return_byte_alignment);
58
59 #ifdef ACPI_UNDER_DEVELOPMENT
60
61 static u32
62 acpi_ex_generate_access(u32 field_bit_offset,
63                         u32 field_bit_length, u32 region_length);
64
65 /*******************************************************************************
66  *
67  * FUNCTION:    acpi_ex_generate_access
68  *
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
72  *
73  * RETURN:      Field granularity (8, 16, 32 or 64) and
74  *              byte_alignment (1, 2, 3, or 4)
75  *
76  * DESCRIPTION: Generate an optimal access width for fields defined with the
77  *              any_acc keyword.
78  *
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
83  *       been evaluated.
84  *
85  ******************************************************************************/
86
87 static u32
88 acpi_ex_generate_access(u32 field_bit_offset,
89                         u32 field_bit_length, u32 region_length)
90 {
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;
96         u32 field_end_offset;
97         u32 minimum_access_width = 0xFFFFFFFF;
98         u32 minimum_accesses = 0xFFFFFFFF;
99         u32 accesses;
100
101         ACPI_FUNCTION_TRACE(ex_generate_access);
102
103         /* Round Field start offset and length to "minimal" byte boundaries */
104
105         field_byte_offset = ACPI_DIV_8(ACPI_ROUND_DOWN(field_bit_offset, 8));
106
107         field_byte_end_offset =
108             ACPI_DIV_8(ACPI_ROUND_UP(field_bit_length + field_bit_offset, 8));
109
110         field_byte_length = field_byte_end_offset - field_byte_offset;
111
112         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
113                           "Bit length %u, Bit offset %u\n",
114                           field_bit_length, field_bit_offset));
115
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));
120
121         /*
122          * Iterative search for the maximum access width that is both aligned
123          * and does not go beyond the end of the region
124          *
125          * Start at byte_acc and work upwards to qword_acc max. (1,2,4,8 bytes)
126          */
127         for (access_byte_width = 1; access_byte_width <= 8;
128              access_byte_width <<= 1) {
129                 /*
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
134                  *    case yet).
135                  */
136                 if (ACPI_ROUND_UP(field_byte_end_offset, access_byte_width) <=
137                     region_length) {
138                         field_start_offset =
139                             ACPI_ROUND_DOWN(field_byte_offset,
140                                             access_byte_width) /
141                             access_byte_width;
142
143                         field_end_offset =
144                             ACPI_ROUND_UP((field_byte_length +
145                                            field_byte_offset),
146                                           access_byte_width) /
147                             access_byte_width;
148
149                         accesses = field_end_offset - field_start_offset;
150
151                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
152                                           "AccessWidth %u end is within region\n",
153                                           access_byte_width));
154
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,
158                                           accesses));
159
160                         /* Single access is optimal */
161
162                         if (accesses <= 1) {
163                                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
164                                                   "Entire field can be accessed "
165                                                   "with one operation of size %u\n",
166                                                   access_byte_width));
167                                 return_VALUE(access_byte_width);
168                         }
169
170                         /*
171                          * Fits in the region, but requires more than one read/write.
172                          * try the next wider access on next iteration
173                          */
174                         if (accesses < minimum_accesses) {
175                                 minimum_accesses = accesses;
176                                 minimum_access_width = access_byte_width;
177                         }
178                 } else {
179                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
180                                           "AccessWidth %u end is NOT within region\n",
181                                           access_byte_width));
182                         if (access_byte_width == 1) {
183                                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
184                                                   "Field goes beyond end-of-region!\n"));
185
186                                 /* Field does not fit in the region at all */
187
188                                 return_VALUE(0);
189                         }
190
191                         /*
192                          * This width goes beyond the end-of-region, back off to
193                          * previous access
194                          */
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);
199                 }
200         }
201
202         /*
203          * Could not read/write field with one operation,
204          * just use max access width
205          */
206         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
207                           "Cannot access field in one operation, using width 8\n"));
208
209         return_VALUE(8);
210 }
211 #endif                          /* ACPI_UNDER_DEVELOPMENT */
212
213 /*******************************************************************************
214  *
215  * FUNCTION:    acpi_ex_decode_field_access
216  *
217  * PARAMETERS:  obj_desc            - Field object
218  *              field_flags         - Encoded fieldflags (contains access bits)
219  *              return_byte_alignment - Where the byte alignment is returned
220  *
221  * RETURN:      Field granularity (8, 16, 32 or 64) and
222  *              byte_alignment (1, 2, 3, or 4)
223  *
224  * DESCRIPTION: Decode the access_type bits of a field definition.
225  *
226  ******************************************************************************/
227
228 static u32
229 acpi_ex_decode_field_access(union acpi_operand_object *obj_desc,
230                             u8 field_flags, u32 * return_byte_alignment)
231 {
232         u32 access;
233         u32 byte_alignment;
234         u32 bit_length;
235
236         ACPI_FUNCTION_TRACE(ex_decode_field_access);
237
238         access = (field_flags & AML_FIELD_ACCESS_TYPE_MASK);
239
240         switch (access) {
241         case AML_FIELD_ACCESS_ANY:
242
243 #ifdef ACPI_UNDER_DEVELOPMENT
244                 byte_alignment =
245                     acpi_ex_generate_access(obj_desc->common_field.
246                                             start_field_bit_offset,
247                                             obj_desc->common_field.bit_length,
248                                             0xFFFFFFFF
249                                             /* Temp until we pass region_length as parameter */
250                     );
251                 bit_length = byte_alignment * 8;
252 #endif
253
254                 byte_alignment = 1;
255                 bit_length = 8;
256                 break;
257
258         case AML_FIELD_ACCESS_BYTE:
259         case AML_FIELD_ACCESS_BUFFER:   /* ACPI 2.0 (SMBus Buffer) */
260
261                 byte_alignment = 1;
262                 bit_length = 8;
263                 break;
264
265         case AML_FIELD_ACCESS_WORD:
266
267                 byte_alignment = 2;
268                 bit_length = 16;
269                 break;
270
271         case AML_FIELD_ACCESS_DWORD:
272
273                 byte_alignment = 4;
274                 bit_length = 32;
275                 break;
276
277         case AML_FIELD_ACCESS_QWORD:    /* ACPI 2.0 */
278
279                 byte_alignment = 8;
280                 bit_length = 64;
281                 break;
282
283         default:
284
285                 /* Invalid field access type */
286
287                 ACPI_ERROR((AE_INFO, "Unknown field access type 0x%X", access));
288
289                 return_UINT32(0);
290         }
291
292         if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
293                 /*
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.
297                  */
298                 byte_alignment = 1;
299         }
300
301         *return_byte_alignment = byte_alignment;
302         return_UINT32(bit_length);
303 }
304
305 /*******************************************************************************
306  *
307  * FUNCTION:    acpi_ex_prep_common_field_object
308  *
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
316  *
317  * RETURN:      Status
318  *
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
322  *              alignment.
323  *
324  ******************************************************************************/
325
326 acpi_status
327 acpi_ex_prep_common_field_object(union acpi_operand_object *obj_desc,
328                                  u8 field_flags,
329                                  u8 field_attribute,
330                                  u32 field_bit_position, u32 field_bit_length)
331 {
332         u32 access_bit_width;
333         u32 byte_alignment;
334         u32 nearest_byte_address;
335
336         ACPI_FUNCTION_TRACE(ex_prep_common_field_object);
337
338         /*
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.
342          */
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;
346
347         /*
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.
351          *
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
355          * byte.
356          *
357          * For all Buffer Fields, the byte_alignment is always one byte.
358          *
359          * For all other access types (Byte, Word, Dword, Qword), the Bitwidth is
360          * the same (equivalent) as the byte_alignment.
361          */
362         access_bit_width =
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);
366         }
367
368         /* Setup width (access granularity) fields (values are: 1, 2, 4, 8) */
369
370         obj_desc->common_field.access_byte_width = (u8)
371             ACPI_DIV_8(access_bit_width);
372
373         /*
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.)
378          *
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
381          * region or buffer.
382          */
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);
387
388         /*
389          * start_field_bit_offset is the offset of the first bit of the field within
390          * a field datum.
391          */
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));
395
396         return_ACPI_STATUS(AE_OK);
397 }
398
399 /*******************************************************************************
400  *
401  * FUNCTION:    acpi_ex_prep_field_value
402  *
403  * PARAMETERS:  info    - Contains all field creation info
404  *
405  * RETURN:      Status
406  *
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.
409  *
410  ******************************************************************************/
411
412 acpi_status acpi_ex_prep_field_value(struct acpi_create_field_info *info)
413 {
414         union acpi_operand_object *obj_desc;
415         union acpi_operand_object *second_desc = NULL;
416         acpi_status status;
417         u32 access_byte_width;
418         u32 type;
419
420         ACPI_FUNCTION_TRACE(ex_prep_field_value);
421
422         /* Parameter validation */
423
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);
428                 }
429
430                 type = acpi_ns_get_type(info->region_node);
431                 if (type != ACPI_TYPE_REGION) {
432                         ACPI_ERROR((AE_INFO,
433                                     "Needed Region, found type 0x%X (%s)", type,
434                                     acpi_ut_get_type_name(type)));
435
436                         return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
437                 }
438         }
439
440         /* Allocate a new field object */
441
442         obj_desc = acpi_ut_create_internal_object(info->field_type);
443         if (!obj_desc) {
444                 return_ACPI_STATUS(AE_NO_MEMORY);
445         }
446
447         /* Initialize areas of the object that are common to all fields */
448
449         obj_desc->common_field.node = info->field_node;
450         status = acpi_ex_prep_common_field_object(obj_desc,
451                                                   info->field_flags,
452                                                   info->attribute,
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);
458         }
459
460         /* Initialize areas of the object that are specific to the field type */
461
462         switch (info->field_type) {
463         case ACPI_TYPE_LOCAL_REGION_FIELD:
464
465                 obj_desc->field.region_obj =
466                     acpi_ns_get_attached_object(info->region_node);
467
468                 /* Fields specific to generic_serial_bus fields */
469
470                 obj_desc->field.access_length = info->access_length;
471
472                 if (info->connection_node) {
473                         second_desc = info->connection_node->object;
474                         if (!(second_desc->common.flags & AOPOBJ_DATA_VALID)) {
475                                 status =
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);
480                                 }
481                         }
482
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;
490                 }
491
492                 obj_desc->field.pin_number_index = info->pin_number_index;
493
494                 /* Allow full data read from EC address space */
495
496                 if ((obj_desc->field.region_obj->region.space_id ==
497                      ACPI_ADR_SPACE_EC)
498                     && (obj_desc->common_field.bit_length > 8)) {
499                         access_byte_width =
500                             ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.
501                                                         bit_length);
502
503                         /* Maximum byte width supported is 255 */
504
505                         if (access_byte_width < 256) {
506                                 obj_desc->common_field.access_byte_width =
507                                     (u8)access_byte_width;
508                         }
509                 }
510                 /* An additional reference for the container */
511
512                 acpi_ut_add_reference(obj_desc->field.region_obj);
513
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));
520                 break;
521
522         case ACPI_TYPE_LOCAL_BANK_FIELD:
523
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);
529
530                 /* An additional reference for the attached objects */
531
532                 acpi_ut_add_reference(obj_desc->bank_field.region_obj);
533                 acpi_ut_add_reference(obj_desc->bank_field.bank_obj);
534
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));
542
543                 /*
544                  * Remember location in AML stream of the field unit
545                  * opcode and operands -- since the bank_value
546                  * operands must be evaluated.
547                  */
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;
555
556                 break;
557
558         case ACPI_TYPE_LOCAL_INDEX_FIELD:
559
560                 /* Get the Index and Data registers */
561
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);
566
567                 if (!obj_desc->index_field.data_obj
568                     || !obj_desc->index_field.index_obj) {
569                         ACPI_ERROR((AE_INFO,
570                                     "Null Index Object during field prep"));
571                         acpi_ut_delete_object_desc(obj_desc);
572                         return_ACPI_STATUS(AE_AML_INTERNAL);
573                 }
574
575                 /* An additional reference for the attached objects */
576
577                 acpi_ut_add_reference(obj_desc->index_field.data_obj);
578                 acpi_ut_add_reference(obj_desc->index_field.index_obj);
579
580                 /*
581                  * April 2006: Changed to match MS behavior
582                  *
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
585                  *
586                  * Previously, the value was calculated as an index in terms of the
587                  * width of the Data register, as below:
588                  *
589                  *      obj_desc->index_field.Value = (u32)
590                  *          (Info->field_bit_position / ACPI_MUL_8 (
591                  *              obj_desc->Field.access_byte_width));
592                  *
593                  * February 2006: Tried value as a byte offset:
594                  *      obj_desc->index_field.Value = (u32)
595                  *          ACPI_DIV_8 (Info->field_bit_position);
596                  */
597                 obj_desc->index_field.value =
598                     (u32) ACPI_ROUND_DOWN(ACPI_DIV_8(info->field_bit_position),
599                                           obj_desc->index_field.
600                                           access_byte_width);
601
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));
611                 break;
612
613         default:
614
615                 /* No other types should get here */
616
617                 break;
618         }
619
620         /*
621          * Store the constructed descriptor (obj_desc) into the parent Node,
622          * preserving the current type of that named_obj.
623          */
624         status =
625             acpi_ns_attach_object(info->field_node, obj_desc,
626                                   acpi_ns_get_type(info->field_node));
627
628         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
629                           "Set NamedObj %p [%4.4s], ObjDesc %p\n",
630                           info->field_node,
631                           acpi_ut_get_node_name(info->field_node), obj_desc));
632
633         /* Remove local reference to the object */
634
635         acpi_ut_remove_reference(obj_desc);
636         return_ACPI_STATUS(status);
637 }