1/******************************************************************************
2 *
3 * Module Name: exprep - ACPI AML (p-code) execution - field prep utilities
4 *
5 *****************************************************************************/
6
7/*
8 * Copyright (C) 2000 - 2015, 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
52ACPI_MODULE_NAME("exprep")
53
54/* Local prototypes */
55static u32
56acpi_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
61static u32
62acpi_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
87static u32
88acpi_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	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;
109
110	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
111			  "Bit length %u, Bit offset %u\n",
112			  field_bit_length, field_bit_offset));
113
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));
118
119	/*
120	 * Iterative search for the maximum access width that is both aligned
121	 * and does not go beyond the end of the region
122	 *
123	 * Start at byte_acc and work upwards to qword_acc max. (1,2,4,8 bytes)
124	 */
125	for (access_byte_width = 1; access_byte_width <= 8;
126	     access_byte_width <<= 1) {
127		/*
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
132		 *    case yet).
133		 */
134		if (ACPI_ROUND_UP(field_byte_end_offset, access_byte_width) <=
135		    region_length) {
136			field_start_offset =
137			    ACPI_ROUND_DOWN(field_byte_offset,
138					    access_byte_width) /
139			    access_byte_width;
140
141			field_end_offset =
142			    ACPI_ROUND_UP((field_byte_length +
143					   field_byte_offset),
144					  access_byte_width) /
145			    access_byte_width;
146
147			accesses = field_end_offset - field_start_offset;
148
149			ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
150					  "AccessWidth %u end is within region\n",
151					  access_byte_width));
152
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,
156					  accesses));
157
158			/* Single access is optimal */
159
160			if (accesses <= 1) {
161				ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
162						  "Entire field can be accessed with one operation of size %u\n",
163						  access_byte_width));
164				return_VALUE(access_byte_width);
165			}
166
167			/*
168			 * Fits in the region, but requires more than one read/write.
169			 * try the next wider access on next iteration
170			 */
171			if (accesses < minimum_accesses) {
172				minimum_accesses = accesses;
173				minimum_access_width = access_byte_width;
174			}
175		} else {
176			ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
177					  "AccessWidth %u end is NOT within region\n",
178					  access_byte_width));
179			if (access_byte_width == 1) {
180				ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
181						  "Field goes beyond end-of-region!\n"));
182
183				/* Field does not fit in the region at all */
184
185				return_VALUE(0);
186			}
187
188			/*
189			 * This width goes beyond the end-of-region, back off to
190			 * previous access
191			 */
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);
196		}
197	}
198
199	/*
200	 * Could not read/write field with one operation,
201	 * just use max access width
202	 */
203	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
204			  "Cannot access field in one operation, using width 8\n"));
205	return_VALUE(8);
206}
207#endif				/* ACPI_UNDER_DEVELOPMENT */
208
209/*******************************************************************************
210 *
211 * FUNCTION:    acpi_ex_decode_field_access
212 *
213 * PARAMETERS:  obj_desc            - Field object
214 *              field_flags         - Encoded fieldflags (contains access bits)
215 *              return_byte_alignment - Where the byte alignment is returned
216 *
217 * RETURN:      Field granularity (8, 16, 32 or 64) and
218 *              byte_alignment (1, 2, 3, or 4)
219 *
220 * DESCRIPTION: Decode the access_type bits of a field definition.
221 *
222 ******************************************************************************/
223
224static u32
225acpi_ex_decode_field_access(union acpi_operand_object *obj_desc,
226			    u8 field_flags, u32 * return_byte_alignment)
227{
228	u32 access;
229	u32 byte_alignment;
230	u32 bit_length;
231
232	ACPI_FUNCTION_TRACE(ex_decode_field_access);
233
234	access = (field_flags & AML_FIELD_ACCESS_TYPE_MASK);
235
236	switch (access) {
237	case AML_FIELD_ACCESS_ANY:
238
239#ifdef ACPI_UNDER_DEVELOPMENT
240		byte_alignment =
241		    acpi_ex_generate_access(obj_desc->common_field.
242					    start_field_bit_offset,
243					    obj_desc->common_field.bit_length,
244					    0xFFFFFFFF
245					    /* Temp until we pass region_length as parameter */
246		    );
247		bit_length = byte_alignment * 8;
248#endif
249
250		byte_alignment = 1;
251		bit_length = 8;
252		break;
253
254	case AML_FIELD_ACCESS_BYTE:
255	case AML_FIELD_ACCESS_BUFFER:	/* ACPI 2.0 (SMBus Buffer) */
256
257		byte_alignment = 1;
258		bit_length = 8;
259		break;
260
261	case AML_FIELD_ACCESS_WORD:
262
263		byte_alignment = 2;
264		bit_length = 16;
265		break;
266
267	case AML_FIELD_ACCESS_DWORD:
268
269		byte_alignment = 4;
270		bit_length = 32;
271		break;
272
273	case AML_FIELD_ACCESS_QWORD:	/* ACPI 2.0 */
274
275		byte_alignment = 8;
276		bit_length = 64;
277		break;
278
279	default:
280
281		/* Invalid field access type */
282
283		ACPI_ERROR((AE_INFO, "Unknown field access type 0x%X", access));
284		return_UINT32(0);
285	}
286
287	if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
288		/*
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.
292		 */
293		byte_alignment = 1;
294	}
295
296	*return_byte_alignment = byte_alignment;
297	return_UINT32(bit_length);
298}
299
300/*******************************************************************************
301 *
302 * FUNCTION:    acpi_ex_prep_common_field_object
303 *
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
311 *
312 * RETURN:      Status
313 *
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
317 *              alignment.
318 *
319 ******************************************************************************/
320
321acpi_status
322acpi_ex_prep_common_field_object(union acpi_operand_object *obj_desc,
323				 u8 field_flags,
324				 u8 field_attribute,
325				 u32 field_bit_position, u32 field_bit_length)
326{
327	u32 access_bit_width;
328	u32 byte_alignment;
329	u32 nearest_byte_address;
330
331	ACPI_FUNCTION_TRACE(ex_prep_common_field_object);
332
333	/*
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.
337	 */
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;
341
342	/*
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.
346	 *
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
350	 * byte.
351	 *
352	 * For all Buffer Fields, the byte_alignment is always one byte.
353	 *
354	 * For all other access types (Byte, Word, Dword, Qword), the Bitwidth is
355	 * the same (equivalent) as the byte_alignment.
356	 */
357	access_bit_width = acpi_ex_decode_field_access(obj_desc, field_flags,
358						       &byte_alignment);
359	if (!access_bit_width) {
360		return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
361	}
362
363	/* Setup width (access granularity) fields (values are: 1, 2, 4, 8) */
364
365	obj_desc->common_field.access_byte_width = (u8)
366	    ACPI_DIV_8(access_bit_width);
367
368	/*
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.)
373	 *
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
376	 * region or buffer.
377	 */
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);
382
383	/*
384	 * start_field_bit_offset is the offset of the first bit of the field within
385	 * a field datum.
386	 */
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));
390
391	return_ACPI_STATUS(AE_OK);
392}
393
394/*******************************************************************************
395 *
396 * FUNCTION:    acpi_ex_prep_field_value
397 *
398 * PARAMETERS:  info    - Contains all field creation info
399 *
400 * RETURN:      Status
401 *
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.
404 *
405 ******************************************************************************/
406
407acpi_status acpi_ex_prep_field_value(struct acpi_create_field_info *info)
408{
409	union acpi_operand_object *obj_desc;
410	union acpi_operand_object *second_desc = NULL;
411	acpi_status status;
412	u32 access_byte_width;
413	u32 type;
414
415	ACPI_FUNCTION_TRACE(ex_prep_field_value);
416
417	/* Parameter validation */
418
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);
423		}
424
425		type = acpi_ns_get_type(info->region_node);
426		if (type != ACPI_TYPE_REGION) {
427			ACPI_ERROR((AE_INFO,
428				    "Needed Region, found type 0x%X (%s)", type,
429				    acpi_ut_get_type_name(type)));
430
431			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
432		}
433	}
434
435	/* Allocate a new field object */
436
437	obj_desc = acpi_ut_create_internal_object(info->field_type);
438	if (!obj_desc) {
439		return_ACPI_STATUS(AE_NO_MEMORY);
440	}
441
442	/* Initialize areas of the object that are common to all fields */
443
444	obj_desc->common_field.node = info->field_node;
445	status = acpi_ex_prep_common_field_object(obj_desc,
446						  info->field_flags,
447						  info->attribute,
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);
453	}
454
455	/* Initialize areas of the object that are specific to the field type */
456
457	switch (info->field_type) {
458	case ACPI_TYPE_LOCAL_REGION_FIELD:
459
460		obj_desc->field.region_obj =
461		    acpi_ns_get_attached_object(info->region_node);
462
463		/* Fields specific to generic_serial_bus fields */
464
465		obj_desc->field.access_length = info->access_length;
466
467		if (info->connection_node) {
468			second_desc = info->connection_node->object;
469			if (!(second_desc->common.flags & AOPOBJ_DATA_VALID)) {
470				status =
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);
475				}
476			}
477
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;
485		}
486
487		obj_desc->field.pin_number_index = info->pin_number_index;
488
489		/* Allow full data read from EC address space */
490
491		if ((obj_desc->field.region_obj->region.space_id ==
492		     ACPI_ADR_SPACE_EC)
493		    && (obj_desc->common_field.bit_length > 8)) {
494			access_byte_width =
495			    ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.
496							bit_length);
497
498			/* Maximum byte width supported is 255 */
499
500			if (access_byte_width < 256) {
501				obj_desc->common_field.access_byte_width =
502				    (u8)access_byte_width;
503			}
504		}
505		/* An additional reference for the container */
506
507		acpi_ut_add_reference(obj_desc->field.region_obj);
508
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));
515		break;
516
517	case ACPI_TYPE_LOCAL_BANK_FIELD:
518
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);
524
525		/* An additional reference for the attached objects */
526
527		acpi_ut_add_reference(obj_desc->bank_field.region_obj);
528		acpi_ut_add_reference(obj_desc->bank_field.bank_obj);
529
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));
537
538		/*
539		 * Remember location in AML stream of the field unit
540		 * opcode and operands -- since the bank_value
541		 * operands must be evaluated.
542		 */
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;
550
551		break;
552
553	case ACPI_TYPE_LOCAL_INDEX_FIELD:
554
555		/* Get the Index and Data registers */
556
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);
561
562		if (!obj_desc->index_field.data_obj
563		    || !obj_desc->index_field.index_obj) {
564			ACPI_ERROR((AE_INFO,
565				    "Null Index Object during field prep"));
566			acpi_ut_delete_object_desc(obj_desc);
567			return_ACPI_STATUS(AE_AML_INTERNAL);
568		}
569
570		/* An additional reference for the attached objects */
571
572		acpi_ut_add_reference(obj_desc->index_field.data_obj);
573		acpi_ut_add_reference(obj_desc->index_field.index_obj);
574
575		/*
576		 * April 2006: Changed to match MS behavior
577		 *
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
580		 *
581		 * Previously, the value was calculated as an index in terms of the
582		 * width of the Data register, as below:
583		 *
584		 *      obj_desc->index_field.Value = (u32)
585		 *          (Info->field_bit_position / ACPI_MUL_8 (
586		 *              obj_desc->Field.access_byte_width));
587		 *
588		 * February 2006: Tried value as a byte offset:
589		 *      obj_desc->index_field.Value = (u32)
590		 *          ACPI_DIV_8 (Info->field_bit_position);
591		 */
592		obj_desc->index_field.value =
593		    (u32) ACPI_ROUND_DOWN(ACPI_DIV_8(info->field_bit_position),
594					  obj_desc->index_field.
595					  access_byte_width);
596
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));
605		break;
606
607	default:
608
609		/* No other types should get here */
610
611		break;
612	}
613
614	/*
615	 * Store the constructed descriptor (obj_desc) into the parent Node,
616	 * preserving the current type of that named_obj.
617	 */
618	status = acpi_ns_attach_object(info->field_node, obj_desc,
619				       acpi_ns_get_type(info->field_node));
620
621	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
622			  "Set NamedObj %p [%4.4s], ObjDesc %p\n",
623			  info->field_node,
624			  acpi_ut_get_node_name(info->field_node), obj_desc));
625
626	/* Remove local reference to the object */
627
628	acpi_ut_remove_reference(obj_desc);
629	return_ACPI_STATUS(status);
630}
631