1 /******************************************************************************
2 *
3 * Module Name: exfield - ACPI AML (p-code) execution - field manipulation
4 *
5 *****************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2004, 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
45 #include <acpi/acpi.h>
46 #include <acpi/acdispat.h>
47 #include <acpi/acinterp.h>
48
49
50 #define _COMPONENT ACPI_EXECUTER
51 ACPI_MODULE_NAME ("exfield")
52
53
54 /*******************************************************************************
55 *
56 * FUNCTION: acpi_ex_read_data_from_field
57 *
58 * PARAMETERS: walk_state - Current execution state
59 * obj_desc - The named field
60 * ret_buffer_desc - Where the return data object is stored
61 *
62 * RETURN: Status
63 *
64 * DESCRIPTION: Read from a named field. Returns either an Integer or a
65 * Buffer, depending on the size of the field.
66 *
67 ******************************************************************************/
68
69 acpi_status
acpi_ex_read_data_from_field(struct acpi_walk_state * walk_state,union acpi_operand_object * obj_desc,union acpi_operand_object ** ret_buffer_desc)70 acpi_ex_read_data_from_field (
71 struct acpi_walk_state *walk_state,
72 union acpi_operand_object *obj_desc,
73 union acpi_operand_object **ret_buffer_desc)
74 {
75 acpi_status status;
76 union acpi_operand_object *buffer_desc;
77 acpi_size length;
78 void *buffer;
79 u8 locked;
80
81
82 ACPI_FUNCTION_TRACE_PTR ("ex_read_data_from_field", obj_desc);
83
84
85 /* Parameter validation */
86
87 if (!obj_desc) {
88 return_ACPI_STATUS (AE_AML_NO_OPERAND);
89 }
90
91 if (ACPI_GET_OBJECT_TYPE (obj_desc) == ACPI_TYPE_BUFFER_FIELD) {
92 /*
93 * If the buffer_field arguments have not been previously evaluated,
94 * evaluate them now and save the results.
95 */
96 if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
97 status = acpi_ds_get_buffer_field_arguments (obj_desc);
98 if (ACPI_FAILURE (status)) {
99 return_ACPI_STATUS (status);
100 }
101 }
102 }
103 else if ((ACPI_GET_OBJECT_TYPE (obj_desc) == ACPI_TYPE_LOCAL_REGION_FIELD) &&
104 (obj_desc->field.region_obj->region.space_id == ACPI_ADR_SPACE_SMBUS)) {
105 /*
106 * This is an SMBus read. We must create a buffer to hold the data
107 * and directly access the region handler.
108 */
109 buffer_desc = acpi_ut_create_buffer_object (ACPI_SMBUS_BUFFER_SIZE);
110 if (!buffer_desc) {
111 return_ACPI_STATUS (AE_NO_MEMORY);
112 }
113
114 /* Lock entire transaction if requested */
115
116 locked = acpi_ex_acquire_global_lock (obj_desc->common_field.field_flags);
117
118 /*
119 * Perform the read.
120 * Note: Smbus protocol value is passed in upper 16-bits of Function
121 */
122 status = acpi_ex_access_region (obj_desc, 0,
123 ACPI_CAST_PTR (acpi_integer, buffer_desc->buffer.pointer),
124 ACPI_READ | (obj_desc->field.attribute << 16));
125 acpi_ex_release_global_lock (locked);
126 goto exit;
127 }
128
129 /*
130 * Allocate a buffer for the contents of the field.
131 *
132 * If the field is larger than the size of an acpi_integer, create
133 * a BUFFER to hold it. Otherwise, use an INTEGER. This allows
134 * the use of arithmetic operators on the returned value if the
135 * field size is equal or smaller than an Integer.
136 *
137 * Note: Field.length is in bits.
138 */
139 length = (acpi_size) ACPI_ROUND_BITS_UP_TO_BYTES (obj_desc->field.bit_length);
140 if (length > acpi_gbl_integer_byte_width) {
141 /* Field is too large for an Integer, create a Buffer instead */
142
143 buffer_desc = acpi_ut_create_buffer_object (length);
144 if (!buffer_desc) {
145 return_ACPI_STATUS (AE_NO_MEMORY);
146 }
147 buffer = buffer_desc->buffer.pointer;
148 }
149 else {
150 /* Field will fit within an Integer (normal case) */
151
152 buffer_desc = acpi_ut_create_internal_object (ACPI_TYPE_INTEGER);
153 if (!buffer_desc) {
154 return_ACPI_STATUS (AE_NO_MEMORY);
155 }
156
157 length = acpi_gbl_integer_byte_width;
158 buffer_desc->integer.value = 0;
159 buffer = &buffer_desc->integer.value;
160 }
161
162 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
163 "field_read [TO]: Obj %p, Type %X, Buf %p, byte_len %X\n",
164 obj_desc, ACPI_GET_OBJECT_TYPE (obj_desc), buffer, (u32) length));
165 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
166 "field_read [FROM]: bit_len %X, bit_off %X, byte_off %X\n",
167 obj_desc->common_field.bit_length,
168 obj_desc->common_field.start_field_bit_offset,
169 obj_desc->common_field.base_byte_offset));
170
171 /* Lock entire transaction if requested */
172
173 locked = acpi_ex_acquire_global_lock (obj_desc->common_field.field_flags);
174
175 /* Read from the field */
176
177 status = acpi_ex_extract_from_field (obj_desc, buffer, (u32) length);
178 acpi_ex_release_global_lock (locked);
179
180
181 exit:
182 if (ACPI_FAILURE (status)) {
183 acpi_ut_remove_reference (buffer_desc);
184 }
185 else if (ret_buffer_desc) {
186 *ret_buffer_desc = buffer_desc;
187 }
188
189 return_ACPI_STATUS (status);
190 }
191
192
193 /*******************************************************************************
194 *
195 * FUNCTION: acpi_ex_write_data_to_field
196 *
197 * PARAMETERS: source_desc - Contains data to write
198 * obj_desc - The named field
199 *
200 * RETURN: Status
201 *
202 * DESCRIPTION: Write to a named field
203 *
204 ******************************************************************************/
205
206 acpi_status
acpi_ex_write_data_to_field(union acpi_operand_object * source_desc,union acpi_operand_object * obj_desc,union acpi_operand_object ** result_desc)207 acpi_ex_write_data_to_field (
208 union acpi_operand_object *source_desc,
209 union acpi_operand_object *obj_desc,
210 union acpi_operand_object **result_desc)
211 {
212 acpi_status status;
213 u32 length;
214 u32 required_length;
215 void *buffer;
216 void *new_buffer;
217 u8 locked;
218 union acpi_operand_object *buffer_desc;
219
220
221 ACPI_FUNCTION_TRACE_PTR ("ex_write_data_to_field", obj_desc);
222
223
224 /* Parameter validation */
225
226 if (!source_desc || !obj_desc) {
227 return_ACPI_STATUS (AE_AML_NO_OPERAND);
228 }
229
230 if (ACPI_GET_OBJECT_TYPE (obj_desc) == ACPI_TYPE_BUFFER_FIELD) {
231 /*
232 * If the buffer_field arguments have not been previously evaluated,
233 * evaluate them now and save the results.
234 */
235 if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
236 status = acpi_ds_get_buffer_field_arguments (obj_desc);
237 if (ACPI_FAILURE (status)) {
238 return_ACPI_STATUS (status);
239 }
240 }
241 }
242 else if ((ACPI_GET_OBJECT_TYPE (obj_desc) == ACPI_TYPE_LOCAL_REGION_FIELD) &&
243 (obj_desc->field.region_obj->region.space_id == ACPI_ADR_SPACE_SMBUS)) {
244 /*
245 * This is an SMBus write. We will bypass the entire field mechanism
246 * and handoff the buffer directly to the handler.
247 *
248 * Source must be a buffer of sufficient size (ACPI_SMBUS_BUFFER_SIZE).
249 */
250 if (ACPI_GET_OBJECT_TYPE (source_desc) != ACPI_TYPE_BUFFER) {
251 ACPI_REPORT_ERROR (("SMBus write requires Buffer, found type %s\n",
252 acpi_ut_get_object_type_name (source_desc)));
253 return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
254 }
255
256 if (source_desc->buffer.length < ACPI_SMBUS_BUFFER_SIZE) {
257 ACPI_REPORT_ERROR (("SMBus write requires Buffer of length %X, found length %X\n",
258 ACPI_SMBUS_BUFFER_SIZE, source_desc->buffer.length));
259 return_ACPI_STATUS (AE_AML_BUFFER_LIMIT);
260 }
261
262 buffer_desc = acpi_ut_create_buffer_object (ACPI_SMBUS_BUFFER_SIZE);
263 if (!buffer_desc) {
264 return_ACPI_STATUS (AE_NO_MEMORY);
265 }
266
267 buffer = buffer_desc->buffer.pointer;
268 ACPI_MEMCPY (buffer, source_desc->buffer.pointer, ACPI_SMBUS_BUFFER_SIZE);
269
270 /* Lock entire transaction if requested */
271
272 locked = acpi_ex_acquire_global_lock (obj_desc->common_field.field_flags);
273
274 /*
275 * Perform the write (returns status and perhaps data in the same buffer)
276 * Note: SMBus protocol type is passed in upper 16-bits of Function.
277 */
278 status = acpi_ex_access_region (obj_desc, 0,
279 (acpi_integer *) buffer,
280 ACPI_WRITE | (obj_desc->field.attribute << 16));
281 acpi_ex_release_global_lock (locked);
282
283 *result_desc = buffer_desc;
284 return_ACPI_STATUS (status);
285 }
286
287 /*
288 * Get a pointer to the data to be written
289 */
290 switch (ACPI_GET_OBJECT_TYPE (source_desc)) {
291 case ACPI_TYPE_INTEGER:
292 buffer = &source_desc->integer.value;
293 length = sizeof (source_desc->integer.value);
294 break;
295
296 case ACPI_TYPE_BUFFER:
297 buffer = source_desc->buffer.pointer;
298 length = source_desc->buffer.length;
299 break;
300
301 case ACPI_TYPE_STRING:
302 buffer = source_desc->string.pointer;
303 length = source_desc->string.length;
304 break;
305
306 default:
307 return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
308 }
309
310 /*
311 * We must have a buffer that is at least as long as the field
312 * we are writing to. This is because individual fields are
313 * indivisible and partial writes are not supported -- as per
314 * the ACPI specification.
315 */
316 new_buffer = NULL;
317 required_length = ACPI_ROUND_BITS_UP_TO_BYTES (obj_desc->common_field.bit_length);
318
319 if (length < required_length) {
320 /* We need to create a new buffer */
321
322 new_buffer = ACPI_MEM_CALLOCATE (required_length);
323 if (!new_buffer) {
324 return_ACPI_STATUS (AE_NO_MEMORY);
325 }
326
327 /*
328 * Copy the original data to the new buffer, starting
329 * at Byte zero. All unused (upper) bytes of the
330 * buffer will be 0.
331 */
332 ACPI_MEMCPY ((char *) new_buffer, (char *) buffer, length);
333 buffer = new_buffer;
334 length = required_length;
335 }
336
337 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
338 "field_write [FROM]: Obj %p (%s:%X), Buf %p, byte_len %X\n",
339 source_desc, acpi_ut_get_type_name (ACPI_GET_OBJECT_TYPE (source_desc)),
340 ACPI_GET_OBJECT_TYPE (source_desc), buffer, length));
341 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
342 "field_write [TO]: Obj %p (%s:%X), bit_len %X, bit_off %X, byte_off %X\n",
343 obj_desc, acpi_ut_get_type_name (ACPI_GET_OBJECT_TYPE (obj_desc)),
344 ACPI_GET_OBJECT_TYPE (obj_desc),
345 obj_desc->common_field.bit_length,
346 obj_desc->common_field.start_field_bit_offset,
347 obj_desc->common_field.base_byte_offset));
348
349 /* Lock entire transaction if requested */
350
351 locked = acpi_ex_acquire_global_lock (obj_desc->common_field.field_flags);
352
353 /* Write to the field */
354
355 status = acpi_ex_insert_into_field (obj_desc, buffer, length);
356 acpi_ex_release_global_lock (locked);
357
358 /* Free temporary buffer if we used one */
359
360 if (new_buffer) {
361 ACPI_MEM_FREE (new_buffer);
362 }
363
364 return_ACPI_STATUS (status);
365 }
366
367
368