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
  17 ACPI_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
  25 static const 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
  71 acpi_status
  72 acpi_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
 104 acpi_status
 105 acpi_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
 237 exit:
 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
 261 acpi_status
 262 acpi_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 }