LXR linux/drivers/acpi/acpica/exfield.c

   1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
   2/******************************************************************************
   3 *
   4 * Module Name: exfield - AML execution - field_unit read/write
   5 *
   6 * Copyright (C) 2000 - 2020, Intel Corp.
   7 *
   8 *****************************************************************************/
   9
  10#include <acpi/acpi.h>
  11#include "accommon.h"
  12#include "acdispat.h"
  13#include "acinterp.h"
  14#include "amlcode.h"
  15
  16#define _COMPONENT          ACPI_EXECUTER
  17ACPI_MODULE_NAME("exfield")
  18
  19/*
  20 * This table maps the various Attrib protocols to the byte transfer
  21 * length. Used for the generic serial bus.
  22 */
  23#define ACPI_INVALID_PROTOCOL_ID        0x80
  24#define ACPI_MAX_PROTOCOL_ID            0x0F
  25const u8 acpi_protocol_lengths[] = {
  26        ACPI_INVALID_PROTOCOL_ID,       /* 0 - reserved */
  27        ACPI_INVALID_PROTOCOL_ID,       /* 1 - reserved */
  28        0x00,                   /* 2 - ATTRIB_QUICK */
  29        ACPI_INVALID_PROTOCOL_ID,       /* 3 - reserved */
  30        0x01,                   /* 4 - ATTRIB_SEND_RECEIVE */
  31        ACPI_INVALID_PROTOCOL_ID,       /* 5 - reserved */
  32        0x01,                   /* 6 - ATTRIB_BYTE */
  33        ACPI_INVALID_PROTOCOL_ID,       /* 7 - reserved */
  34        0x02,                   /* 8 - ATTRIB_WORD */
  35        ACPI_INVALID_PROTOCOL_ID,       /* 9 - reserved */
  36        0xFF,                   /* A - ATTRIB_BLOCK  */
  37        0xFF,                   /* B - ATTRIB_BYTES */
  38        0x02,                   /* C - ATTRIB_PROCESS_CALL */
  39        0xFF,                   /* D - ATTRIB_BLOCK_PROCESS_CALL */
  40        0xFF,                   /* E - ATTRIB_RAW_BYTES */
  41        0xFF                    /* F - ATTRIB_RAW_PROCESS_BYTES */
  42};
  43
  44#define PCC_MASTER_SUBSPACE     3
  45
  46/*
  47 * The following macros determine a given offset is a COMD field.
  48 * According to the specification, generic subspaces (types 0-2) contains a
  49 * 2-byte COMD field at offset 4 and master subspaces (type 3) contains a 4-byte
  50 * COMD field starting at offset 12.
  51 */
  52#define GENERIC_SUBSPACE_COMMAND(a)     (4 == a || a == 5)
  53#define MASTER_SUBSPACE_COMMAND(a)      (12 <= a && a <= 15)
  54
  55/*******************************************************************************
  56 *
  57 * FUNCTION:    acpi_ex_get_protocol_buffer_length
  58 *
  59 * PARAMETERS:  protocol_id     - The type of the protocol indicated by region
  60 *                                field access attributes
  61 *              return_length   - Where the protocol byte transfer length is
  62 *                                returned
  63 *
  64 * RETURN:      Status and decoded byte transfer length
  65 *
  66 * DESCRIPTION: This routine returns the length of the generic_serial_bus
  67 *              protocol bytes
  68 *
  69 ******************************************************************************/
  70
  71acpi_status
  72acpi_ex_get_protocol_buffer_length(u32 protocol_id, u32 *return_length)
  73{
  74
  75        if ((protocol_id > ACPI_MAX_PROTOCOL_ID) ||
  76            (acpi_protocol_lengths[protocol_id] == ACPI_INVALID_PROTOCOL_ID)) {
  77                ACPI_ERROR((AE_INFO,
  78                            "Invalid Field/AccessAs protocol ID: 0x%4.4X",
  79                            protocol_id));
  80
  81                return (AE_AML_PROTOCOL);
  82        }
  83
  84        *return_length = acpi_protocol_lengths[protocol_id];
  85        return (AE_OK);
  86}
  87
  88/*******************************************************************************
  89 *
  90 * FUNCTION:    acpi_ex_read_data_from_field
  91 *
  92 * PARAMETERS:  walk_state          - Current execution state
  93 *              obj_desc            - The named field
  94 *              ret_buffer_desc     - Where the return data object is stored
  95 *
  96 * RETURN:      Status
  97 *
  98 * DESCRIPTION: Read from a named field. Returns either an Integer or a
  99 *              Buffer, depending on the size of the field and whether if a
 100 *              field is created by the create_field() operator.
 101 *
 102 ******************************************************************************/
 103
 104acpi_status
 105acpi_ex_read_data_from_field(struct acpi_walk_state *walk_state,
 106                             union acpi_operand_object *obj_desc,
 107                             union acpi_operand_object **ret_buffer_desc)
 108{
 109        acpi_status status;
 110        union acpi_operand_object *buffer_desc;
 111        void *buffer;
 112        u32 buffer_length;
 113
 114        ACPI_FUNCTION_TRACE_PTR(ex_read_data_from_field, obj_desc);
 115
 116        /* Parameter validation */
 117
 118        if (!obj_desc) {
 119                return_ACPI_STATUS(AE_AML_NO_OPERAND);
 120        }
 121        if (!ret_buffer_desc) {
 122                return_ACPI_STATUS(AE_BAD_PARAMETER);
 123        }
 124
 125        if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
 126                /*
 127                 * If the buffer_field arguments have not been previously evaluated,
 128                 * evaluate them now and save the results.
 129                 */
 130                if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
 131                        status = acpi_ds_get_buffer_field_arguments(obj_desc);
 132                        if (ACPI_FAILURE(status)) {
 133                                return_ACPI_STATUS(status);
 134                        }
 135                }
 136        } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 137                   (obj_desc->field.region_obj->region.space_id ==
 138                    ACPI_ADR_SPACE_SMBUS
 139                    || obj_desc->field.region_obj->region.space_id ==
 140                    ACPI_ADR_SPACE_GSBUS
 141                    || obj_desc->field.region_obj->region.space_id ==
 142                    ACPI_ADR_SPACE_IPMI)) {
 143
 144                /* SMBus, GSBus, IPMI serial */
 145
 146                status = acpi_ex_read_serial_bus(obj_desc, ret_buffer_desc);
 147                return_ACPI_STATUS(status);
 148        }
 149
 150        /*
 151         * Allocate a buffer for the contents of the field.
 152         *
 153         * If the field is larger than the current integer width, create
 154         * a BUFFER to hold it. Otherwise, use an INTEGER. This allows
 155         * the use of arithmetic operators on the returned value if the
 156         * field size is equal or smaller than an Integer.
 157         *
 158         * However, all buffer fields created by create_field operator needs to
 159         * remain as a buffer to match other AML interpreter implementations.
 160         *
 161         * Note: Field.length is in bits.
 162         */
 163        buffer_length =
 164            (acpi_size)ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.bit_length);
 165
 166        if (buffer_length > acpi_gbl_integer_byte_width ||
 167            (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD &&
 168             obj_desc->buffer_field.is_create_field)) {
 169
 170                /* Field is too large for an Integer, create a Buffer instead */
 171
 172                buffer_desc = acpi_ut_create_buffer_object(buffer_length);
 173                if (!buffer_desc) {
 174                        return_ACPI_STATUS(AE_NO_MEMORY);
 175                }
 176                buffer = buffer_desc->buffer.pointer;
 177        } else {
 178                /* Field will fit within an Integer (normal case) */
 179
 180                buffer_desc = acpi_ut_create_integer_object((u64) 0);
 181                if (!buffer_desc) {
 182                        return_ACPI_STATUS(AE_NO_MEMORY);
 183                }
 184
 185                buffer_length = acpi_gbl_integer_byte_width;
 186                buffer = &buffer_desc->integer.value;
 187        }
 188
 189        if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 190            (obj_desc->field.region_obj->region.space_id ==
 191             ACPI_ADR_SPACE_GPIO)) {
 192
 193                /* General Purpose I/O */
 194
 195                status = acpi_ex_read_gpio(obj_desc, buffer);
 196                goto exit;
 197        } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 198                   (obj_desc->field.region_obj->region.space_id ==
 199                    ACPI_ADR_SPACE_PLATFORM_COMM)) {
 200                /*
 201                 * Reading from a PCC field unit does not require the handler because
 202                 * it only requires reading from the internal_pcc_buffer.
 203                 */
 204                ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 205                                  "PCC FieldRead bits %u\n",
 206                                  obj_desc->field.bit_length));
 207
 208                memcpy(buffer,
 209                       obj_desc->field.region_obj->field.internal_pcc_buffer +
 210                       obj_desc->field.base_byte_offset,
 211                       (acpi_size)ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.
 212                                                              bit_length));
 213
 214                *ret_buffer_desc = buffer_desc;
 215                return AE_OK;
 216        }
 217
 218        ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 219                          "FieldRead [TO]:   Obj %p, Type %X, Buf %p, ByteLen %X\n",
 220                          obj_desc, obj_desc->common.type, buffer,
 221                          buffer_length));
 222        ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 223                          "FieldRead [FROM]: BitLen %X, BitOff %X, ByteOff %X\n",
 224                          obj_desc->common_field.bit_length,
 225                          obj_desc->common_field.start_field_bit_offset,
 226                          obj_desc->common_field.base_byte_offset));
 227
 228        /* Lock entire transaction if requested */
 229
 230        acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 231
 232        /* Read from the field */
 233
 234        status = acpi_ex_extract_from_field(obj_desc, buffer, buffer_length);
 235        acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
 236
 237exit:
 238        if (ACPI_FAILURE(status)) {
 239                acpi_ut_remove_reference(buffer_desc);
 240        } else {
 241                *ret_buffer_desc = buffer_desc;
 242        }
 243
 244        return_ACPI_STATUS(status);
 245}
 246
 247/*******************************************************************************
 248 *
 249 * FUNCTION:    acpi_ex_write_data_to_field
 250 *
 251 * PARAMETERS:  source_desc         - Contains data to write
 252 *              obj_desc            - The named field
 253 *              result_desc         - Where the return value is returned, if any
 254 *
 255 * RETURN:      Status
 256 *
 257 * DESCRIPTION: Write to a named field
 258 *
 259 ******************************************************************************/
 260
 261acpi_status
 262acpi_ex_write_data_to_field(union acpi_operand_object *source_desc,
 263                            union acpi_operand_object *obj_desc,
 264                            union acpi_operand_object **result_desc)
 265{
 266        acpi_status status;
 267        u32 buffer_length;
 268        u32 data_length;
 269        void *buffer;
 270
 271        ACPI_FUNCTION_TRACE_PTR(ex_write_data_to_field, obj_desc);
 272
 273        /* Parameter validation */
 274
 275        if (!source_desc || !obj_desc) {
 276                return_ACPI_STATUS(AE_AML_NO_OPERAND);
 277        }
 278
 279        if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
 280                /*
 281                 * If the buffer_field arguments have not been previously evaluated,
 282                 * evaluate them now and save the results.
 283                 */
 284                if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
 285                        status = acpi_ds_get_buffer_field_arguments(obj_desc);
 286                        if (ACPI_FAILURE(status)) {
 287                                return_ACPI_STATUS(status);
 288                        }
 289                }
 290        } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 291                   (obj_desc->field.region_obj->region.space_id ==
 292                    ACPI_ADR_SPACE_GPIO)) {
 293
 294                /* General Purpose I/O */
 295
 296                status = acpi_ex_write_gpio(source_desc, obj_desc, result_desc);
 297                return_ACPI_STATUS(status);
 298        } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 299                   (obj_desc->field.region_obj->region.space_id ==
 300                    ACPI_ADR_SPACE_SMBUS
 301                    || obj_desc->field.region_obj->region.space_id ==
 302                    ACPI_ADR_SPACE_GSBUS
 303                    || obj_desc->field.region_obj->region.space_id ==
 304                    ACPI_ADR_SPACE_IPMI)) {
 305
 306                /* SMBus, GSBus, IPMI serial */
 307
 308                status =
 309                    acpi_ex_write_serial_bus(source_desc, obj_desc,
 310                                             result_desc);
 311                return_ACPI_STATUS(status);
 312        } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 313                   (obj_desc->field.region_obj->region.space_id ==
 314                    ACPI_ADR_SPACE_PLATFORM_COMM)) {
 315                /*
 316                 * According to the spec a write to the COMD field will invoke the
 317                 * region handler. Otherwise, write to the pcc_internal buffer. This
 318                 * implementation will use the offsets specified rather than the name
 319                 * of the field. This is considered safer because some firmware tools
 320                 * are known to obfiscate named objects.
 321                 */
 322                data_length =
 323                    (acpi_size)ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.
 324                                                           bit_length);
 325                memcpy(obj_desc->field.region_obj->field.internal_pcc_buffer +
 326                       obj_desc->field.base_byte_offset,
 327                       source_desc->buffer.pointer, data_length);
 328
 329                if ((obj_desc->field.region_obj->region.address ==
 330                     PCC_MASTER_SUBSPACE
 331                     && MASTER_SUBSPACE_COMMAND(obj_desc->field.
 332                                                base_byte_offset))
 333                    || GENERIC_SUBSPACE_COMMAND(obj_desc->field.
 334                                                base_byte_offset)) {
 335
 336                        /* Perform the write */
 337
 338                        ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 339                                          "PCC COMD field has been written. Invoking PCC handler now.\n"));
 340
 341                        status =
 342                            acpi_ex_access_region(obj_desc, 0,
 343                                                  (u64 *)obj_desc->field.
 344                                                  region_obj->field.
 345                                                  internal_pcc_buffer,
 346                                                  ACPI_WRITE);
 347                        return_ACPI_STATUS(status);
 348                }
 349                return (AE_OK);
 350        }
 351
 352        /* Get a pointer to the data to be written */
 353
 354        switch (source_desc->common.type) {
 355        case ACPI_TYPE_INTEGER:
 356
 357                buffer = &source_desc->integer.value;
 358                buffer_length = sizeof(source_desc->integer.value);
 359                break;
 360
 361        case ACPI_TYPE_BUFFER:
 362
 363                buffer = source_desc->buffer.pointer;
 364                buffer_length = source_desc->buffer.length;
 365                break;
 366
 367        case ACPI_TYPE_STRING:
 368
 369                buffer = source_desc->string.pointer;
 370                buffer_length = source_desc->string.length;
 371                break;
 372
 373        default:
 374                return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 375        }
 376
 377        ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 378                          "FieldWrite [FROM]: Obj %p (%s:%X), Buf %p, ByteLen %X\n",
 379                          source_desc,
 380                          acpi_ut_get_type_name(source_desc->common.type),
 381                          source_desc->common.type, buffer, buffer_length));
 382
 383        ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 384                          "FieldWrite [TO]:   Obj %p (%s:%X), BitLen %X, BitOff %X, ByteOff %X\n",
 385                          obj_desc,
 386                          acpi_ut_get_type_name(obj_desc->common.type),
 387                          obj_desc->common.type,
 388                          obj_desc->common_field.bit_length,
 389                          obj_desc->common_field.start_field_bit_offset,
 390                          obj_desc->common_field.base_byte_offset));
 391
 392        /* Lock entire transaction if requested */
 393
 394        acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 395
 396        /* Write to the field */
 397
 398        status = acpi_ex_insert_into_field(obj_desc, buffer, buffer_length);
 399        acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
 400        return_ACPI_STATUS(status);
 401}
 402