1/****************************************************************************** 2 * 3 * Module Name: exfield - ACPI AML (p-code) execution - field manipulation 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/acdispat.h> 46#include <acpi/acinterp.h> 47 48#define _COMPONENT ACPI_EXECUTER 49ACPI_MODULE_NAME("exfield") 50 51/******************************************************************************* 52 * 53 * FUNCTION: acpi_ex_read_data_from_field 54 * 55 * PARAMETERS: walk_state - Current execution state 56 * obj_desc - The named field 57 * ret_buffer_desc - Where the return data object is stored 58 * 59 * RETURN: Status 60 * 61 * DESCRIPTION: Read from a named field. Returns either an Integer or a 62 * Buffer, depending on the size of the field. 63 * 64 ******************************************************************************/ 65acpi_status 66acpi_ex_read_data_from_field(struct acpi_walk_state *walk_state, 67 union acpi_operand_object *obj_desc, 68 union acpi_operand_object **ret_buffer_desc) 69{ 70 acpi_status status; 71 union acpi_operand_object *buffer_desc; 72 acpi_size length; 73 void *buffer; 74 u8 locked; 75 76 ACPI_FUNCTION_TRACE_PTR(ex_read_data_from_field, obj_desc); 77 78 /* Parameter validation */ 79 80 if (!obj_desc) { 81 return_ACPI_STATUS(AE_AML_NO_OPERAND); 82 } 83 if (!ret_buffer_desc) { 84 return_ACPI_STATUS(AE_BAD_PARAMETER); 85 } 86 87 if (ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_BUFFER_FIELD) { 88 /* 89 * If the buffer_field arguments have not been previously evaluated, 90 * evaluate them now and save the results. 91 */ 92 if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) { 93 status = acpi_ds_get_buffer_field_arguments(obj_desc); 94 if (ACPI_FAILURE(status)) { 95 return_ACPI_STATUS(status); 96 } 97 } 98 } else 99 if ((ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_LOCAL_REGION_FIELD) 100 && (obj_desc->field.region_obj->region.space_id == 101 ACPI_ADR_SPACE_SMBUS)) { 102 /* 103 * This is an SMBus read. We must create a buffer to hold the data 104 * and directly access the region handler. 105 */ 106 buffer_desc = 107 acpi_ut_create_buffer_object(ACPI_SMBUS_BUFFER_SIZE); 108 if (!buffer_desc) { 109 return_ACPI_STATUS(AE_NO_MEMORY); 110 } 111 112 /* Lock entire transaction if requested */ 113 114 locked = 115 acpi_ex_acquire_global_lock(obj_desc->common_field. 116 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, 124 buffer_desc-> 125 buffer.pointer), 126 ACPI_READ | (obj_desc->field. 127 attribute << 16)); 128 acpi_ex_release_global_lock(locked); 129 goto exit; 130 } 131 132 /* 133 * Allocate a buffer for the contents of the field. 134 * 135 * If the field is larger than the size of an acpi_integer, create 136 * a BUFFER to hold it. Otherwise, use an INTEGER. This allows 137 * the use of arithmetic operators on the returned value if the 138 * field size is equal or smaller than an Integer. 139 * 140 * Note: Field.length is in bits. 141 */ 142 length = 143 (acpi_size) ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.bit_length); 144 if (length > acpi_gbl_integer_byte_width) { 145 146 /* Field is too large for an Integer, create a Buffer instead */ 147 148 buffer_desc = acpi_ut_create_buffer_object(length); 149 if (!buffer_desc) { 150 return_ACPI_STATUS(AE_NO_MEMORY); 151 } 152 buffer = buffer_desc->buffer.pointer; 153 } else { 154 /* Field will fit within an Integer (normal case) */ 155 156 buffer_desc = acpi_ut_create_internal_object(ACPI_TYPE_INTEGER); 157 if (!buffer_desc) { 158 return_ACPI_STATUS(AE_NO_MEMORY); 159 } 160 161 length = acpi_gbl_integer_byte_width; 162 buffer_desc->integer.value = 0; 163 buffer = &buffer_desc->integer.value; 164 } 165 166 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 167 "FieldRead [TO]: Obj %p, Type %X, Buf %p, ByteLen %X\n", 168 obj_desc, ACPI_GET_OBJECT_TYPE(obj_desc), buffer, 169 (u32) length)); 170 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 171 "FieldRead [FROM]: BitLen %X, BitOff %X, ByteOff %X\n", 172 obj_desc->common_field.bit_length, 173 obj_desc->common_field.start_field_bit_offset, 174 obj_desc->common_field.base_byte_offset)); 175 176 /* Lock entire transaction if requested */ 177 178 locked = 179 acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags); 180 181 /* Read from the field */ 182 183 status = acpi_ex_extract_from_field(obj_desc, buffer, (u32) length); 184 acpi_ex_release_global_lock(locked); 185 186 exit: 187 if (ACPI_FAILURE(status)) { 188 acpi_ut_remove_reference(buffer_desc); 189 } else { 190 *ret_buffer_desc = buffer_desc; 191 } 192 193 return_ACPI_STATUS(status); 194} 195 196/******************************************************************************* 197 * 198 * FUNCTION: acpi_ex_write_data_to_field 199 * 200 * PARAMETERS: source_desc - Contains data to write 201 * obj_desc - The named field 202 * result_desc - Where the return value is returned, if any 203 * 204 * RETURN: Status 205 * 206 * DESCRIPTION: Write to a named field 207 * 208 ******************************************************************************/ 209 210acpi_status 211acpi_ex_write_data_to_field(union acpi_operand_object *source_desc, 212 union acpi_operand_object *obj_desc, 213 union acpi_operand_object **result_desc) 214{ 215 acpi_status status; 216 u32 length; 217 u32 required_length; 218 void *buffer; 219 void *new_buffer; 220 u8 locked; 221 union acpi_operand_object *buffer_desc; 222 223 ACPI_FUNCTION_TRACE_PTR(ex_write_data_to_field, obj_desc); 224 225 /* Parameter validation */ 226 227 if (!source_desc || !obj_desc) { 228 return_ACPI_STATUS(AE_AML_NO_OPERAND); 229 } 230 231 if (ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_BUFFER_FIELD) { 232 /* 233 * If the buffer_field arguments have not been previously evaluated, 234 * evaluate them now and save the results. 235 */ 236 if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) { 237 status = acpi_ds_get_buffer_field_arguments(obj_desc); 238 if (ACPI_FAILURE(status)) { 239 return_ACPI_STATUS(status); 240 } 241 } 242 } else 243 if ((ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_LOCAL_REGION_FIELD) 244 && (obj_desc->field.region_obj->region.space_id == 245 ACPI_ADR_SPACE_SMBUS)) { 246 /* 247 * This is an SMBus write. We will bypass the entire field mechanism 248 * and handoff the buffer directly to the handler. 249 * 250 * Source must be a buffer of sufficient size (ACPI_SMBUS_BUFFER_SIZE). 251 */ 252 if (ACPI_GET_OBJECT_TYPE(source_desc) != ACPI_TYPE_BUFFER) { 253 ACPI_ERROR((AE_INFO, 254 "SMBus write requires Buffer, found type %s", 255 acpi_ut_get_object_type_name(source_desc))); 256 257 return_ACPI_STATUS(AE_AML_OPERAND_TYPE); 258 } 259 260 if (source_desc->buffer.length < ACPI_SMBUS_BUFFER_SIZE) { 261 ACPI_ERROR((AE_INFO, 262 "SMBus write requires Buffer of length %X, found length %X", 263 ACPI_SMBUS_BUFFER_SIZE, 264 source_desc->buffer.length)); 265 266 return_ACPI_STATUS(AE_AML_BUFFER_LIMIT); 267 } 268 269 buffer_desc = 270 acpi_ut_create_buffer_object(ACPI_SMBUS_BUFFER_SIZE); 271 if (!buffer_desc) { 272 return_ACPI_STATUS(AE_NO_MEMORY); 273 } 274 275 buffer = buffer_desc->buffer.pointer; 276 ACPI_MEMCPY(buffer, source_desc->buffer.pointer, 277 ACPI_SMBUS_BUFFER_SIZE); 278 279 /* Lock entire transaction if requested */ 280 281 locked = 282 acpi_ex_acquire_global_lock(obj_desc->common_field. 283 field_flags); 284 285 /* 286 * Perform the write (returns status and perhaps data in the 287 * same buffer) 288 * Note: SMBus protocol type is passed in upper 16-bits of Function. 289 */ 290 status = acpi_ex_access_region(obj_desc, 0, 291 (acpi_integer *) buffer, 292 ACPI_WRITE | (obj_desc->field. 293 attribute << 16)); 294 acpi_ex_release_global_lock(locked); 295 296 *result_desc = buffer_desc; 297 return_ACPI_STATUS(status); 298 } 299 300 /* Get a pointer to the data to be written */ 301 302 switch (ACPI_GET_OBJECT_TYPE(source_desc)) { 303 case ACPI_TYPE_INTEGER: 304 buffer = &source_desc->integer.value; 305 length = sizeof(source_desc->integer.value); 306 break; 307 308 case ACPI_TYPE_BUFFER: 309 buffer = source_desc->buffer.pointer; 310 length = source_desc->buffer.length; 311 break; 312 313 case ACPI_TYPE_STRING: 314 buffer = source_desc->string.pointer; 315 length = source_desc->string.length; 316 break; 317 318 default: 319 return_ACPI_STATUS(AE_AML_OPERAND_TYPE); 320 } 321 322 /* 323 * We must have a buffer that is at least as long as the field 324 * we are writing to. This is because individual fields are 325 * indivisible and partial writes are not supported -- as per 326 * the ACPI specification. 327 */ 328 new_buffer = NULL; 329 required_length = 330 ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.bit_length); 331 332 if (length < required_length) { 333 334 /* We need to create a new buffer */ 335 336 new_buffer = ACPI_ALLOCATE_ZEROED(required_length); 337 if (!new_buffer) { 338 return_ACPI_STATUS(AE_NO_MEMORY); 339 } 340 341 /* 342 * Copy the original data to the new buffer, starting 343 * at Byte zero. All unused (upper) bytes of the 344 * buffer will be 0. 345 */ 346 ACPI_MEMCPY((char *)new_buffer, (char *)buffer, length); 347 buffer = new_buffer; 348 length = required_length; 349 } 350 351 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 352 "FieldWrite [FROM]: Obj %p (%s:%X), Buf %p, ByteLen %X\n", 353 source_desc, 354 acpi_ut_get_type_name(ACPI_GET_OBJECT_TYPE 355 (source_desc)), 356 ACPI_GET_OBJECT_TYPE(source_desc), buffer, length)); 357 358 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 359 "FieldWrite [TO]: Obj %p (%s:%X), BitLen %X, BitOff %X, ByteOff %X\n", 360 obj_desc, 361 acpi_ut_get_type_name(ACPI_GET_OBJECT_TYPE(obj_desc)), 362 ACPI_GET_OBJECT_TYPE(obj_desc), 363 obj_desc->common_field.bit_length, 364 obj_desc->common_field.start_field_bit_offset, 365 obj_desc->common_field.base_byte_offset)); 366 367 /* Lock entire transaction if requested */ 368 369 locked = 370 acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags); 371 372 /* Write to the field */ 373 374 status = acpi_ex_insert_into_field(obj_desc, buffer, length); 375 acpi_ex_release_global_lock(locked); 376 377 /* Free temporary buffer if we used one */ 378 379 if (new_buffer) { 380 ACPI_FREE(new_buffer); 381 } 382 383 return_ACPI_STATUS(status); 384} 385