drivers/acpi/acpica/exfield.c

   1 /******************************************************************************
   2  *
   3  * Module Name: exfield - ACPI AML (p-code) execution - field manipulation
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2013, 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 "acdispat.h"
  47 #include "acinterp.h"
  48
  49 #define _COMPONENT          ACPI_EXECUTER
  50 ACPI_MODULE_NAME("exfield")
  51
  52 /*******************************************************************************
  53  *
  54  * FUNCTION:    acpi_ex_read_data_from_field
  55  *
  56  * PARAMETERS:  walk_state          - Current execution state
  57  *              obj_desc            - The named field
  58  *              ret_buffer_desc     - Where the return data object is stored
  59  *
  60  * RETURN:      Status
  61  *
  62  * DESCRIPTION: Read from a named field. Returns either an Integer or a
  63  *              Buffer, depending on the size of the field.
  64  *
  65  ******************************************************************************/
  66 acpi_status
  67 acpi_ex_read_data_from_field(struct acpi_walk_state *walk_state,
  68                              union acpi_operand_object *obj_desc,
  69                              union acpi_operand_object **ret_buffer_desc)
  70 {
  71         acpi_status status;
  72         union acpi_operand_object *buffer_desc;
  73         acpi_size length;
  74         void *buffer;
  75         u32 function;
  76
  77         ACPI_FUNCTION_TRACE_PTR(ex_read_data_from_field, obj_desc);
  78
  79         /* Parameter validation */
  80
  81         if (!obj_desc) {
  82                 return_ACPI_STATUS(AE_AML_NO_OPERAND);
  83         }
  84         if (!ret_buffer_desc) {
  85                 return_ACPI_STATUS(AE_BAD_PARAMETER);
  86         }
  87
  88         if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
  89                 /*
  90                  * If the buffer_field arguments have not been previously evaluated,
  91                  * evaluate them now and save the results.
  92                  */
  93                 if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
  94                         status = acpi_ds_get_buffer_field_arguments(obj_desc);
  95                         if (ACPI_FAILURE(status)) {
  96                                 return_ACPI_STATUS(status);
  97                         }
  98                 }
  99         } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 100                    (obj_desc->field.region_obj->region.space_id ==
 101                     ACPI_ADR_SPACE_SMBUS
 102                     || obj_desc->field.region_obj->region.space_id ==
 103                     ACPI_ADR_SPACE_GSBUS
 104                     || obj_desc->field.region_obj->region.space_id ==
 105                     ACPI_ADR_SPACE_IPMI)) {
 106                 /*
 107                  * This is an SMBus, GSBus or IPMI read. We must create a buffer to hold
 108                  * the data and then directly access the region handler.
 109                  *
 110                  * Note: SMBus and GSBus protocol value is passed in upper 16-bits of Function
 111                  */
 112                 if (obj_desc->field.region_obj->region.space_id ==
 113                     ACPI_ADR_SPACE_SMBUS) {
 114                         length = ACPI_SMBUS_BUFFER_SIZE;
 115                         function =
 116                             ACPI_READ | (obj_desc->field.attribute << 16);
 117                 } else if (obj_desc->field.region_obj->region.space_id ==
 118                            ACPI_ADR_SPACE_GSBUS) {
 119                         length = ACPI_GSBUS_BUFFER_SIZE;
 120                         function =
 121                             ACPI_READ | (obj_desc->field.attribute << 16);
 122                 } else {        /* IPMI */
 123
 124                         length = ACPI_IPMI_BUFFER_SIZE;
 125                         function = ACPI_READ;
 126                 }
 127
 128                 buffer_desc = acpi_ut_create_buffer_object(length);
 129                 if (!buffer_desc) {
 130                         return_ACPI_STATUS(AE_NO_MEMORY);
 131                 }
 132
 133                 /* Lock entire transaction if requested */
 134
 135                 acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 136
 137                 /* Call the region handler for the read */
 138
 139                 status = acpi_ex_access_region(obj_desc, 0,
 140                                                ACPI_CAST_PTR(u64,
 141                                                              buffer_desc->
 142                                                              buffer.pointer),
 143                                                function);
 144                 acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
 145                 goto exit;
 146         }
 147
 148         /*
 149          * Allocate a buffer for the contents of the field.
 150          *
 151          * If the field is larger than the current integer width, create
 152          * a BUFFER to hold it. Otherwise, use an INTEGER. This allows
 153          * the use of arithmetic operators on the returned value if the
 154          * field size is equal or smaller than an Integer.
 155          *
 156          * Note: Field.length is in bits.
 157          */
 158         length =
 159             (acpi_size) ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.bit_length);
 160         if (length > acpi_gbl_integer_byte_width) {
 161
 162                 /* Field is too large for an Integer, create a Buffer instead */
 163
 164                 buffer_desc = acpi_ut_create_buffer_object(length);
 165                 if (!buffer_desc) {
 166                         return_ACPI_STATUS(AE_NO_MEMORY);
 167                 }
 168                 buffer = buffer_desc->buffer.pointer;
 169         } else {
 170                 /* Field will fit within an Integer (normal case) */
 171
 172                 buffer_desc = acpi_ut_create_integer_object((u64) 0);
 173                 if (!buffer_desc) {
 174                         return_ACPI_STATUS(AE_NO_MEMORY);
 175                 }
 176
 177                 length = acpi_gbl_integer_byte_width;
 178                 buffer = &buffer_desc->integer.value;
 179         }
 180
 181         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 182                           "FieldRead [TO]:   Obj %p, Type %X, Buf %p, ByteLen %X\n",
 183                           obj_desc, obj_desc->common.type, buffer,
 184                           (u32) length));
 185         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 186                           "FieldRead [FROM]: BitLen %X, BitOff %X, ByteOff %X\n",
 187                           obj_desc->common_field.bit_length,
 188                           obj_desc->common_field.start_field_bit_offset,
 189                           obj_desc->common_field.base_byte_offset));
 190
 191         /* Lock entire transaction if requested */
 192
 193         acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 194
 195         /* Read from the field */
 196
 197         status = acpi_ex_extract_from_field(obj_desc, buffer, (u32) length);
 198         acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
 199
 200       exit:
 201         if (ACPI_FAILURE(status)) {
 202                 acpi_ut_remove_reference(buffer_desc);
 203         } else {
 204                 *ret_buffer_desc = buffer_desc;
 205         }
 206
 207         return_ACPI_STATUS(status);
 208 }
 209
 210 /*******************************************************************************
 211  *
 212  * FUNCTION:    acpi_ex_write_data_to_field
 213  *
 214  * PARAMETERS:  source_desc         - Contains data to write
 215  *              obj_desc            - The named field
 216  *              result_desc         - Where the return value is returned, if any
 217  *
 218  * RETURN:      Status
 219  *
 220  * DESCRIPTION: Write to a named field
 221  *
 222  ******************************************************************************/
 223
 224 acpi_status
 225 acpi_ex_write_data_to_field(union acpi_operand_object *source_desc,
 226                             union acpi_operand_object *obj_desc,
 227                             union acpi_operand_object **result_desc)
 228 {
 229         acpi_status status;
 230         u32 length;
 231         void *buffer;
 232         union acpi_operand_object *buffer_desc;
 233         u32 function;
 234
 235         ACPI_FUNCTION_TRACE_PTR(ex_write_data_to_field, obj_desc);
 236
 237         /* Parameter validation */
 238
 239         if (!source_desc || !obj_desc) {
 240                 return_ACPI_STATUS(AE_AML_NO_OPERAND);
 241         }
 242
 243         if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
 244                 /*
 245                  * If the buffer_field arguments have not been previously evaluated,
 246                  * evaluate them now and save the results.
 247                  */
 248                 if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
 249                         status = acpi_ds_get_buffer_field_arguments(obj_desc);
 250                         if (ACPI_FAILURE(status)) {
 251                                 return_ACPI_STATUS(status);
 252                         }
 253                 }
 254         } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 255                    (obj_desc->field.region_obj->region.space_id ==
 256                     ACPI_ADR_SPACE_SMBUS
 257                     || obj_desc->field.region_obj->region.space_id ==
 258                     ACPI_ADR_SPACE_GSBUS
 259                     || obj_desc->field.region_obj->region.space_id ==
 260                     ACPI_ADR_SPACE_IPMI)) {
 261                 /*
 262                  * This is an SMBus, GSBus or IPMI write. We will bypass the entire field
 263                  * mechanism and handoff the buffer directly to the handler. For
 264                  * these address spaces, the buffer is bi-directional; on a write,
 265                  * return data is returned in the same buffer.
 266                  *
 267                  * Source must be a buffer of sufficient size:
 268                  * ACPI_SMBUS_BUFFER_SIZE, ACPI_GSBUS_BUFFER_SIZE, or ACPI_IPMI_BUFFER_SIZE.
 269                  *
 270                  * Note: SMBus and GSBus protocol type is passed in upper 16-bits of Function
 271                  */
 272                 if (source_desc->common.type != ACPI_TYPE_BUFFER) {
 273                         ACPI_ERROR((AE_INFO,
 274                                     "SMBus/IPMI/GenericSerialBus write requires Buffer, found type %s",
 275                                     acpi_ut_get_object_type_name(source_desc)));
 276
 277                         return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 278                 }
 279
 280                 if (obj_desc->field.region_obj->region.space_id ==
 281                     ACPI_ADR_SPACE_SMBUS) {
 282                         length = ACPI_SMBUS_BUFFER_SIZE;
 283                         function =
 284                             ACPI_WRITE | (obj_desc->field.attribute << 16);
 285                 } else if (obj_desc->field.region_obj->region.space_id ==
 286                            ACPI_ADR_SPACE_GSBUS) {
 287                         length = ACPI_GSBUS_BUFFER_SIZE;
 288                         function =
 289                             ACPI_WRITE | (obj_desc->field.attribute << 16);
 290                 } else {        /* IPMI */
 291
 292                         length = ACPI_IPMI_BUFFER_SIZE;
 293                         function = ACPI_WRITE;
 294                 }
 295
 296                 if (source_desc->buffer.length < length) {
 297                         ACPI_ERROR((AE_INFO,
 298                                     "SMBus/IPMI/GenericSerialBus write requires Buffer of length %u, found length %u",
 299                                     length, source_desc->buffer.length));
 300
 301                         return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
 302                 }
 303
 304                 /* Create the bi-directional buffer */
 305
 306                 buffer_desc = acpi_ut_create_buffer_object(length);
 307                 if (!buffer_desc) {
 308                         return_ACPI_STATUS(AE_NO_MEMORY);
 309                 }
 310
 311                 buffer = buffer_desc->buffer.pointer;
 312                 ACPI_MEMCPY(buffer, source_desc->buffer.pointer, length);
 313
 314                 /* Lock entire transaction if requested */
 315
 316                 acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 317
 318                 /*
 319                  * Perform the write (returns status and perhaps data in the
 320                  * same buffer)
 321                  */
 322                 status = acpi_ex_access_region(obj_desc, 0,
 323                                                (u64 *) buffer, function);
 324                 acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
 325
 326                 *result_desc = buffer_desc;
 327                 return_ACPI_STATUS(status);
 328         }
 329
 330         /* Get a pointer to the data to be written */
 331
 332         switch (source_desc->common.type) {
 333         case ACPI_TYPE_INTEGER:
 334
 335                 buffer = &source_desc->integer.value;
 336                 length = sizeof(source_desc->integer.value);
 337                 break;
 338
 339         case ACPI_TYPE_BUFFER:
 340
 341                 buffer = source_desc->buffer.pointer;
 342                 length = source_desc->buffer.length;
 343                 break;
 344
 345         case ACPI_TYPE_STRING:
 346
 347                 buffer = source_desc->string.pointer;
 348                 length = source_desc->string.length;
 349                 break;
 350
 351         default:
 352
 353                 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 354         }
 355
 356         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 357                           "FieldWrite [FROM]: Obj %p (%s:%X), Buf %p, ByteLen %X\n",
 358                           source_desc,
 359                           acpi_ut_get_type_name(source_desc->common.type),
 360                           source_desc->common.type, buffer, length));
 361
 362         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 363                           "FieldWrite [TO]:   Obj %p (%s:%X), BitLen %X, BitOff %X, ByteOff %X\n",
 364                           obj_desc,
 365                           acpi_ut_get_type_name(obj_desc->common.type),
 366                           obj_desc->common.type,
 367                           obj_desc->common_field.bit_length,
 368                           obj_desc->common_field.start_field_bit_offset,
 369                           obj_desc->common_field.base_byte_offset));
 370
 371         /* Lock entire transaction if requested */
 372
 373         acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 374
 375         /* Write to the field */
 376
 377         status = acpi_ex_insert_into_field(obj_desc, buffer, length);
 378         acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
 379
 380         return_ACPI_STATUS(status);
 381 }