LXR linux/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
  50ACPI_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 ******************************************************************************/
  66acpi_status
  67acpi_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
 224acpi_status
 225acpi_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                buffer = &source_desc->integer.value;
 335                length = sizeof(source_desc->integer.value);
 336                break;
 337
 338        case ACPI_TYPE_BUFFER:
 339                buffer = source_desc->buffer.pointer;
 340                length = source_desc->buffer.length;
 341                break;
 342
 343        case ACPI_TYPE_STRING:
 344                buffer = source_desc->string.pointer;
 345                length = source_desc->string.length;
 346                break;
 347
 348        default:
 349                return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 350        }
 351
 352        ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 353                          "FieldWrite [FROM]: Obj %p (%s:%X), Buf %p, ByteLen %X\n",
 354                          source_desc,
 355                          acpi_ut_get_type_name(source_desc->common.type),
 356                          source_desc->common.type, 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(obj_desc->common.type),
 362                          obj_desc->common.type,
 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        acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 370
 371        /* Write to the field */
 372
 373        status = acpi_ex_insert_into_field(obj_desc, buffer, length);
 374        acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
 375
 376        return_ACPI_STATUS(status);
 377}
 378