ACPICA: Implemented full argument resolution support for the BankValue argument to...
[linux-2.6] / drivers / acpi / parser / psargs.c
1 /******************************************************************************
2  *
3  * Module Name: psargs - Parse AML opcode arguments
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2007, R. Byron Moore
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 <acpi/acparser.h>
46 #include <acpi/amlcode.h>
47 #include <acpi/acnamesp.h>
48 #include <acpi/acdispat.h>
49
50 #define _COMPONENT          ACPI_PARSER
51 ACPI_MODULE_NAME("psargs")
52
53 /* Local prototypes */
54 static u32
55 acpi_ps_get_next_package_length(struct acpi_parse_state *parser_state);
56
57 static union acpi_parse_object *acpi_ps_get_next_field(struct acpi_parse_state
58                                                        *parser_state);
59
60 /*******************************************************************************
61  *
62  * FUNCTION:    acpi_ps_get_next_package_length
63  *
64  * PARAMETERS:  parser_state        - Current parser state object
65  *
66  * RETURN:      Decoded package length. On completion, the AML pointer points
67  *              past the length byte or bytes.
68  *
69  * DESCRIPTION: Decode and return a package length field.
70  *              Note: Largest package length is 28 bits, from ACPI specification
71  *
72  ******************************************************************************/
73
74 static u32
75 acpi_ps_get_next_package_length(struct acpi_parse_state *parser_state)
76 {
77         u8 *aml = parser_state->aml;
78         u32 package_length = 0;
79         acpi_native_uint byte_count;
80         u8 byte_zero_mask = 0x3F;       /* Default [0:5] */
81
82         ACPI_FUNCTION_TRACE(ps_get_next_package_length);
83
84         /*
85          * Byte 0 bits [6:7] contain the number of additional bytes
86          * used to encode the package length, either 0,1,2, or 3
87          */
88         byte_count = (aml[0] >> 6);
89         parser_state->aml += (byte_count + 1);
90
91         /* Get bytes 3, 2, 1 as needed */
92
93         while (byte_count) {
94                 /*
95                  * Final bit positions for the package length bytes:
96                  *      Byte3->[20:27]
97                  *      Byte2->[12:19]
98                  *      Byte1->[04:11]
99                  *      Byte0->[00:03]
100                  */
101                 package_length |= (aml[byte_count] << ((byte_count << 3) - 4));
102
103                 byte_zero_mask = 0x0F;  /* Use bits [0:3] of byte 0 */
104                 byte_count--;
105         }
106
107         /* Byte 0 is a special case, either bits [0:3] or [0:5] are used */
108
109         package_length |= (aml[0] & byte_zero_mask);
110         return_UINT32(package_length);
111 }
112
113 /*******************************************************************************
114  *
115  * FUNCTION:    acpi_ps_get_next_package_end
116  *
117  * PARAMETERS:  parser_state        - Current parser state object
118  *
119  * RETURN:      Pointer to end-of-package +1
120  *
121  * DESCRIPTION: Get next package length and return a pointer past the end of
122  *              the package.  Consumes the package length field
123  *
124  ******************************************************************************/
125
126 u8 *acpi_ps_get_next_package_end(struct acpi_parse_state *parser_state)
127 {
128         u8 *start = parser_state->aml;
129         u32 package_length;
130
131         ACPI_FUNCTION_TRACE(ps_get_next_package_end);
132
133         /* Function below updates parser_state->Aml */
134
135         package_length = acpi_ps_get_next_package_length(parser_state);
136
137         return_PTR(start + package_length);     /* end of package */
138 }
139
140 /*******************************************************************************
141  *
142  * FUNCTION:    acpi_ps_get_next_namestring
143  *
144  * PARAMETERS:  parser_state        - Current parser state object
145  *
146  * RETURN:      Pointer to the start of the name string (pointer points into
147  *              the AML.
148  *
149  * DESCRIPTION: Get next raw namestring within the AML stream.  Handles all name
150  *              prefix characters.  Set parser state to point past the string.
151  *              (Name is consumed from the AML.)
152  *
153  ******************************************************************************/
154
155 char *acpi_ps_get_next_namestring(struct acpi_parse_state *parser_state)
156 {
157         u8 *start = parser_state->aml;
158         u8 *end = parser_state->aml;
159
160         ACPI_FUNCTION_TRACE(ps_get_next_namestring);
161
162         /* Point past any namestring prefix characters (backslash or carat) */
163
164         while (acpi_ps_is_prefix_char(*end)) {
165                 end++;
166         }
167
168         /* Decode the path prefix character */
169
170         switch (*end) {
171         case 0:
172
173                 /* null_name */
174
175                 if (end == start) {
176                         start = NULL;
177                 }
178                 end++;
179                 break;
180
181         case AML_DUAL_NAME_PREFIX:
182
183                 /* Two name segments */
184
185                 end += 1 + (2 * ACPI_NAME_SIZE);
186                 break;
187
188         case AML_MULTI_NAME_PREFIX_OP:
189
190                 /* Multiple name segments, 4 chars each, count in next byte */
191
192                 end += 2 + (*(end + 1) * ACPI_NAME_SIZE);
193                 break;
194
195         default:
196
197                 /* Single name segment */
198
199                 end += ACPI_NAME_SIZE;
200                 break;
201         }
202
203         parser_state->aml = end;
204         return_PTR((char *)start);
205 }
206
207 /*******************************************************************************
208  *
209  * FUNCTION:    acpi_ps_get_next_namepath
210  *
211  * PARAMETERS:  parser_state        - Current parser state object
212  *              Arg                 - Where the namepath will be stored
213  *              arg_count           - If the namepath points to a control method
214  *                                    the method's argument is returned here.
215  *              possible_method_call - Whether the namepath can possibly be the
216  *                                    start of a method call
217  *
218  * RETURN:      Status
219  *
220  * DESCRIPTION: Get next name (if method call, return # of required args).
221  *              Names are looked up in the internal namespace to determine
222  *              if the name represents a control method.  If a method
223  *              is found, the number of arguments to the method is returned.
224  *              This information is critical for parsing to continue correctly.
225  *
226  ******************************************************************************/
227
228 acpi_status
229 acpi_ps_get_next_namepath(struct acpi_walk_state *walk_state,
230                           struct acpi_parse_state *parser_state,
231                           union acpi_parse_object *arg, u8 possible_method_call)
232 {
233         acpi_status status;
234         char *path;
235         union acpi_parse_object *name_op;
236         union acpi_operand_object *method_desc;
237         struct acpi_namespace_node *node;
238
239         ACPI_FUNCTION_TRACE(ps_get_next_namepath);
240
241         path = acpi_ps_get_next_namestring(parser_state);
242         acpi_ps_init_op(arg, AML_INT_NAMEPATH_OP);
243
244         /* Null path case is allowed, just exit */
245
246         if (!path) {
247                 arg->common.value.name = path;
248                 return_ACPI_STATUS(AE_OK);
249         }
250
251         /*
252          * Lookup the name in the internal namespace, starting with the current
253          * scope. We don't want to add anything new to the namespace here,
254          * however, so we use MODE_EXECUTE.
255          * Allow searching of the parent tree, but don't open a new scope -
256          * we just want to lookup the object (must be mode EXECUTE to perform
257          * the upsearch)
258          */
259         status = acpi_ns_lookup(walk_state->scope_info, path,
260                                 ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
261                                 ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE,
262                                 NULL, &node);
263
264         /*
265          * If this name is a control method invocation, we must
266          * setup the method call
267          */
268         if (ACPI_SUCCESS(status) &&
269             possible_method_call && (node->type == ACPI_TYPE_METHOD)) {
270
271                 /* This name is actually a control method invocation */
272
273                 method_desc = acpi_ns_get_attached_object(node);
274                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
275                                   "Control Method - %p Desc %p Path=%p\n", node,
276                                   method_desc, path));
277
278                 name_op = acpi_ps_alloc_op(AML_INT_NAMEPATH_OP);
279                 if (!name_op) {
280                         return_ACPI_STATUS(AE_NO_MEMORY);
281                 }
282
283                 /* Change Arg into a METHOD CALL and attach name to it */
284
285                 acpi_ps_init_op(arg, AML_INT_METHODCALL_OP);
286                 name_op->common.value.name = path;
287
288                 /* Point METHODCALL/NAME to the METHOD Node */
289
290                 name_op->common.node = node;
291                 acpi_ps_append_arg(arg, name_op);
292
293                 if (!method_desc) {
294                         ACPI_ERROR((AE_INFO,
295                                     "Control Method %p has no attached object",
296                                     node));
297                         return_ACPI_STATUS(AE_AML_INTERNAL);
298                 }
299
300                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
301                                   "Control Method - %p Args %X\n",
302                                   node, method_desc->method.param_count));
303
304                 /* Get the number of arguments to expect */
305
306                 walk_state->arg_count = method_desc->method.param_count;
307                 return_ACPI_STATUS(AE_OK);
308         }
309
310         /*
311          * Special handling if the name was not found during the lookup -
312          * some not_found cases are allowed
313          */
314         if (status == AE_NOT_FOUND) {
315
316                 /* 1) not_found is ok during load pass 1/2 (allow forward references) */
317
318                 if ((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) !=
319                     ACPI_PARSE_EXECUTE) {
320                         status = AE_OK;
321                 }
322
323                 /* 2) not_found during a cond_ref_of(x) is ok by definition */
324
325                 else if (walk_state->op->common.aml_opcode ==
326                          AML_COND_REF_OF_OP) {
327                         status = AE_OK;
328                 }
329
330                 /*
331                  * 3) not_found while building a Package is ok at this point, we
332                  * may flag as an error later if slack mode is not enabled.
333                  * (Some ASL code depends on allowing this behavior)
334                  */
335                 else if ((arg->common.parent) &&
336                          ((arg->common.parent->common.aml_opcode ==
337                            AML_PACKAGE_OP)
338                           || (arg->common.parent->common.aml_opcode ==
339                               AML_VAR_PACKAGE_OP))) {
340                         status = AE_OK;
341                 }
342         }
343
344         /* Final exception check (may have been changed from code above) */
345
346         if (ACPI_FAILURE(status)) {
347                 ACPI_ERROR_NAMESPACE(path, status);
348
349                 if ((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) ==
350                     ACPI_PARSE_EXECUTE) {
351
352                         /* Report a control method execution error */
353
354                         status = acpi_ds_method_error(status, walk_state);
355                 }
356         }
357
358         /* Save the namepath */
359
360         arg->common.value.name = path;
361         return_ACPI_STATUS(status);
362 }
363
364 /*******************************************************************************
365  *
366  * FUNCTION:    acpi_ps_get_next_simple_arg
367  *
368  * PARAMETERS:  parser_state        - Current parser state object
369  *              arg_type            - The argument type (AML_*_ARG)
370  *              Arg                 - Where the argument is returned
371  *
372  * RETURN:      None
373  *
374  * DESCRIPTION: Get the next simple argument (constant, string, or namestring)
375  *
376  ******************************************************************************/
377
378 void
379 acpi_ps_get_next_simple_arg(struct acpi_parse_state *parser_state,
380                             u32 arg_type, union acpi_parse_object *arg)
381 {
382         u32 length;
383         u16 opcode;
384         u8 *aml = parser_state->aml;
385
386         ACPI_FUNCTION_TRACE_U32(ps_get_next_simple_arg, arg_type);
387
388         switch (arg_type) {
389         case ARGP_BYTEDATA:
390
391                 /* Get 1 byte from the AML stream */
392
393                 opcode = AML_BYTE_OP;
394                 arg->common.value.integer = (acpi_integer) * aml;
395                 length = 1;
396                 break;
397
398         case ARGP_WORDDATA:
399
400                 /* Get 2 bytes from the AML stream */
401
402                 opcode = AML_WORD_OP;
403                 ACPI_MOVE_16_TO_64(&arg->common.value.integer, aml);
404                 length = 2;
405                 break;
406
407         case ARGP_DWORDDATA:
408
409                 /* Get 4 bytes from the AML stream */
410
411                 opcode = AML_DWORD_OP;
412                 ACPI_MOVE_32_TO_64(&arg->common.value.integer, aml);
413                 length = 4;
414                 break;
415
416         case ARGP_QWORDDATA:
417
418                 /* Get 8 bytes from the AML stream */
419
420                 opcode = AML_QWORD_OP;
421                 ACPI_MOVE_64_TO_64(&arg->common.value.integer, aml);
422                 length = 8;
423                 break;
424
425         case ARGP_CHARLIST:
426
427                 /* Get a pointer to the string, point past the string */
428
429                 opcode = AML_STRING_OP;
430                 arg->common.value.string = ACPI_CAST_PTR(char, aml);
431
432                 /* Find the null terminator */
433
434                 length = 0;
435                 while (aml[length]) {
436                         length++;
437                 }
438                 length++;
439                 break;
440
441         case ARGP_NAME:
442         case ARGP_NAMESTRING:
443
444                 acpi_ps_init_op(arg, AML_INT_NAMEPATH_OP);
445                 arg->common.value.name =
446                     acpi_ps_get_next_namestring(parser_state);
447                 return_VOID;
448
449         default:
450
451                 ACPI_ERROR((AE_INFO, "Invalid ArgType %X", arg_type));
452                 return_VOID;
453         }
454
455         acpi_ps_init_op(arg, opcode);
456         parser_state->aml += length;
457         return_VOID;
458 }
459
460 /*******************************************************************************
461  *
462  * FUNCTION:    acpi_ps_get_next_field
463  *
464  * PARAMETERS:  parser_state        - Current parser state object
465  *
466  * RETURN:      A newly allocated FIELD op
467  *
468  * DESCRIPTION: Get next field (named_field, reserved_field, or access_field)
469  *
470  ******************************************************************************/
471
472 static union acpi_parse_object *acpi_ps_get_next_field(struct acpi_parse_state
473                                                        *parser_state)
474 {
475         u32 aml_offset = (u32)
476             ACPI_PTR_DIFF(parser_state->aml,
477                           parser_state->aml_start);
478         union acpi_parse_object *field;
479         u16 opcode;
480         u32 name;
481
482         ACPI_FUNCTION_TRACE(ps_get_next_field);
483
484         /* Determine field type */
485
486         switch (ACPI_GET8(parser_state->aml)) {
487         default:
488
489                 opcode = AML_INT_NAMEDFIELD_OP;
490                 break;
491
492         case 0x00:
493
494                 opcode = AML_INT_RESERVEDFIELD_OP;
495                 parser_state->aml++;
496                 break;
497
498         case 0x01:
499
500                 opcode = AML_INT_ACCESSFIELD_OP;
501                 parser_state->aml++;
502                 break;
503         }
504
505         /* Allocate a new field op */
506
507         field = acpi_ps_alloc_op(opcode);
508         if (!field) {
509                 return_PTR(NULL);
510         }
511
512         field->common.aml_offset = aml_offset;
513
514         /* Decode the field type */
515
516         switch (opcode) {
517         case AML_INT_NAMEDFIELD_OP:
518
519                 /* Get the 4-character name */
520
521                 ACPI_MOVE_32_TO_32(&name, parser_state->aml);
522                 acpi_ps_set_name(field, name);
523                 parser_state->aml += ACPI_NAME_SIZE;
524
525                 /* Get the length which is encoded as a package length */
526
527                 field->common.value.size =
528                     acpi_ps_get_next_package_length(parser_state);
529                 break;
530
531         case AML_INT_RESERVEDFIELD_OP:
532
533                 /* Get the length which is encoded as a package length */
534
535                 field->common.value.size =
536                     acpi_ps_get_next_package_length(parser_state);
537                 break;
538
539         case AML_INT_ACCESSFIELD_OP:
540
541                 /*
542                  * Get access_type and access_attrib and merge into the field Op
543                  * access_type is first operand, access_attribute is second
544                  */
545                 field->common.value.integer =
546                     (((u32) ACPI_GET8(parser_state->aml) << 8));
547                 parser_state->aml++;
548                 field->common.value.integer |= ACPI_GET8(parser_state->aml);
549                 parser_state->aml++;
550                 break;
551
552         default:
553
554                 /* Opcode was set in previous switch */
555                 break;
556         }
557
558         return_PTR(field);
559 }
560
561 /*******************************************************************************
562  *
563  * FUNCTION:    acpi_ps_get_next_arg
564  *
565  * PARAMETERS:  walk_state          - Current state
566  *              parser_state        - Current parser state object
567  *              arg_type            - The argument type (AML_*_ARG)
568  *              return_arg          - Where the next arg is returned
569  *
570  * RETURN:      Status, and an op object containing the next argument.
571  *
572  * DESCRIPTION: Get next argument (including complex list arguments that require
573  *              pushing the parser stack)
574  *
575  ******************************************************************************/
576
577 acpi_status
578 acpi_ps_get_next_arg(struct acpi_walk_state *walk_state,
579                      struct acpi_parse_state *parser_state,
580                      u32 arg_type, union acpi_parse_object **return_arg)
581 {
582         union acpi_parse_object *arg = NULL;
583         union acpi_parse_object *prev = NULL;
584         union acpi_parse_object *field;
585         u32 subop;
586         acpi_status status = AE_OK;
587
588         ACPI_FUNCTION_TRACE_PTR(ps_get_next_arg, parser_state);
589
590         switch (arg_type) {
591         case ARGP_BYTEDATA:
592         case ARGP_WORDDATA:
593         case ARGP_DWORDDATA:
594         case ARGP_CHARLIST:
595         case ARGP_NAME:
596         case ARGP_NAMESTRING:
597
598                 /* Constants, strings, and namestrings are all the same size */
599
600                 arg = acpi_ps_alloc_op(AML_BYTE_OP);
601                 if (!arg) {
602                         return_ACPI_STATUS(AE_NO_MEMORY);
603                 }
604                 acpi_ps_get_next_simple_arg(parser_state, arg_type, arg);
605                 break;
606
607         case ARGP_PKGLENGTH:
608
609                 /* Package length, nothing returned */
610
611                 parser_state->pkg_end =
612                     acpi_ps_get_next_package_end(parser_state);
613                 break;
614
615         case ARGP_FIELDLIST:
616
617                 if (parser_state->aml < parser_state->pkg_end) {
618
619                         /* Non-empty list */
620
621                         while (parser_state->aml < parser_state->pkg_end) {
622                                 field = acpi_ps_get_next_field(parser_state);
623                                 if (!field) {
624                                         return_ACPI_STATUS(AE_NO_MEMORY);
625                                 }
626
627                                 if (prev) {
628                                         prev->common.next = field;
629                                 } else {
630                                         arg = field;
631                                 }
632                                 prev = field;
633                         }
634
635                         /* Skip to End of byte data */
636
637                         parser_state->aml = parser_state->pkg_end;
638                 }
639                 break;
640
641         case ARGP_BYTELIST:
642
643                 if (parser_state->aml < parser_state->pkg_end) {
644
645                         /* Non-empty list */
646
647                         arg = acpi_ps_alloc_op(AML_INT_BYTELIST_OP);
648                         if (!arg) {
649                                 return_ACPI_STATUS(AE_NO_MEMORY);
650                         }
651
652                         /* Fill in bytelist data */
653
654                         arg->common.value.size = (u32)
655                             ACPI_PTR_DIFF(parser_state->pkg_end,
656                                           parser_state->aml);
657                         arg->named.data = parser_state->aml;
658
659                         /* Skip to End of byte data */
660
661                         parser_state->aml = parser_state->pkg_end;
662                 }
663                 break;
664
665         case ARGP_TARGET:
666         case ARGP_SUPERNAME:
667         case ARGP_SIMPLENAME:
668
669                 subop = acpi_ps_peek_opcode(parser_state);
670                 if (subop == 0 ||
671                     acpi_ps_is_leading_char(subop) ||
672                     acpi_ps_is_prefix_char(subop)) {
673
674                         /* null_name or name_string */
675
676                         arg = acpi_ps_alloc_op(AML_INT_NAMEPATH_OP);
677                         if (!arg) {
678                                 return_ACPI_STATUS(AE_NO_MEMORY);
679                         }
680
681                         status =
682                             acpi_ps_get_next_namepath(walk_state, parser_state,
683                                                       arg, 0);
684                 } else {
685                         /* Single complex argument, nothing returned */
686
687                         walk_state->arg_count = 1;
688                 }
689                 break;
690
691         case ARGP_DATAOBJ:
692         case ARGP_TERMARG:
693
694                 /* Single complex argument, nothing returned */
695
696                 walk_state->arg_count = 1;
697                 break;
698
699         case ARGP_DATAOBJLIST:
700         case ARGP_TERMLIST:
701         case ARGP_OBJLIST:
702
703                 if (parser_state->aml < parser_state->pkg_end) {
704
705                         /* Non-empty list of variable arguments, nothing returned */
706
707                         walk_state->arg_count = ACPI_VAR_ARGS;
708                 }
709                 break;
710
711         default:
712
713                 ACPI_ERROR((AE_INFO, "Invalid ArgType: %X", arg_type));
714                 status = AE_AML_OPERAND_TYPE;
715                 break;
716         }
717
718         *return_arg = arg;
719         return_ACPI_STATUS(status);
720 }