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 - 2019, 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 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.
 100  *
 101  ******************************************************************************/
 102
 103 acpi_status
 104 acpi_ex_read_data_from_field(struct acpi_walk_state *walk_state,
 105                              union acpi_operand_object *obj_desc,
 106                              union acpi_operand_object **ret_buffer_desc)
 107 {
 108         acpi_status status;
 109         union acpi_operand_object *buffer_desc;
 110         void *buffer;
 111         u32 buffer_length;
 112
 113         ACPI_FUNCTION_TRACE_PTR(ex_read_data_from_field, obj_desc);
 114
 115         /* Parameter validation */
 116
 117         if (!obj_desc) {
 118                 return_ACPI_STATUS(AE_AML_NO_OPERAND);
 119         }
 120         if (!ret_buffer_desc) {
 121                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 122         }
 123
 124         if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
 125                 /*
 126                  * If the buffer_field arguments have not been previously evaluated,
 127                  * evaluate them now and save the results.
 128                  */
 129                 if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
 130                         status = acpi_ds_get_buffer_field_arguments(obj_desc);
 131                         if (ACPI_FAILURE(status)) {
 132                                 return_ACPI_STATUS(status);
 133                         }
 134                 }
 135         } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 136                    (obj_desc->field.region_obj->region.space_id ==
 137                     ACPI_ADR_SPACE_SMBUS
 138                     || obj_desc->field.region_obj->region.space_id ==
 139                     ACPI_ADR_SPACE_GSBUS
 140                     || obj_desc->field.region_obj->region.space_id ==
 141                     ACPI_ADR_SPACE_IPMI)) {
 142
 143                 /* SMBus, GSBus, IPMI serial */
 144
 145                 status = acpi_ex_read_serial_bus(obj_desc, ret_buffer_desc);
 146                 return_ACPI_STATUS(status);
 147         }
 148
 149         /*
 150          * Allocate a buffer for the contents of the field.
 151          *
 152          * If the field is larger than the current integer width, create
 153          * a BUFFER to hold it. Otherwise, use an INTEGER. This allows
 154          * the use of arithmetic operators on the returned value if the
 155          * field size is equal or smaller than an Integer.
 156          *
 157          * Note: Field.length is in bits.
 158          */
 159         buffer_length =
 160             (acpi_size)ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.bit_length);
 161
 162         if (buffer_length > acpi_gbl_integer_byte_width) {
 163
 164                 /* Field is too large for an Integer, create a Buffer instead */
 165
 166                 buffer_desc = acpi_ut_create_buffer_object(buffer_length);
 167                 if (!buffer_desc) {
 168                         return_ACPI_STATUS(AE_NO_MEMORY);
 169                 }
 170                 buffer = buffer_desc->buffer.pointer;
 171         } else {
 172                 /* Field will fit within an Integer (normal case) */
 173
 174                 buffer_desc = acpi_ut_create_integer_object((u64) 0);
 175                 if (!buffer_desc) {
 176                         return_ACPI_STATUS(AE_NO_MEMORY);
 177                 }
 178
 179                 buffer_length = acpi_gbl_integer_byte_width;
 180                 buffer = &buffer_desc->integer.value;
 181         }
 182
 183         if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 184             (obj_desc->field.region_obj->region.space_id ==
 185              ACPI_ADR_SPACE_GPIO)) {
 186
 187                 /* General Purpose I/O */
 188
 189                 status = acpi_ex_read_gpio(obj_desc, buffer);
 190                 goto exit;
 191         } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 192                    (obj_desc->field.region_obj->region.space_id ==
 193                     ACPI_ADR_SPACE_PLATFORM_COMM)) {
 194                 /*
 195                  * Reading from a PCC field unit does not require the handler because
 196                  * it only requires reading from the internal_pcc_buffer.
 197                  */
 198                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 199                                   "PCC FieldRead bits %u\n",
 200                                   obj_desc->field.bit_length));
 201
 202                 memcpy(buffer,
 203                        obj_desc->field.region_obj->field.internal_pcc_buffer +
 204                        obj_desc->field.base_byte_offset,
 205                        (acpi_size)ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.
 206                                                               bit_length));
 207
 208                 *ret_buffer_desc = buffer_desc;
 209                 return AE_OK;
 210         }
 211
 212         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 213                           "FieldRead [TO]:   Obj %p, Type %X, Buf %p, ByteLen %X\n",
 214                           obj_desc, obj_desc->common.type, buffer,
 215                           buffer_length));
 216         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 217                           "FieldRead [FROM]: BitLen %X, BitOff %X, ByteOff %X\n",
 218                           obj_desc->common_field.bit_length,
 219                           obj_desc->common_field.start_field_bit_offset,
 220                           obj_desc->common_field.base_byte_offset));
 221
 222         /* Lock entire transaction if requested */
 223
 224         acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 225
 226         /* Read from the field */
 227
 228         status = acpi_ex_extract_from_field(obj_desc, buffer, buffer_length);
 229         acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
 230
 231 exit:
 232         if (ACPI_FAILURE(status)) {
 233                 acpi_ut_remove_reference(buffer_desc);
 234         } else {
 235                 *ret_buffer_desc = buffer_desc;
 236         }
 237
 238         return_ACPI_STATUS(status);
 239 }
 240
 241 /*******************************************************************************
 242  *
 243  * FUNCTION:    acpi_ex_write_data_to_field
 244  *
 245  * PARAMETERS:  source_desc         - Contains data to write
 246  *              obj_desc            - The named field
 247  *              result_desc         - Where the return value is returned, if any
 248  *
 249  * RETURN:      Status
 250  *
 251  * DESCRIPTION: Write to a named field
 252  *
 253  ******************************************************************************/
 254
 255 acpi_status
 256 acpi_ex_write_data_to_field(union acpi_operand_object *source_desc,
 257                             union acpi_operand_object *obj_desc,
 258                             union acpi_operand_object **result_desc)
 259 {
 260         acpi_status status;
 261         u32 buffer_length;
 262         u32 data_length;
 263         void *buffer;
 264
 265         ACPI_FUNCTION_TRACE_PTR(ex_write_data_to_field, obj_desc);
 266
 267         /* Parameter validation */
 268
 269         if (!source_desc || !obj_desc) {
 270                 return_ACPI_STATUS(AE_AML_NO_OPERAND);
 271         }
 272
 273         if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
 274                 /*
 275                  * If the buffer_field arguments have not been previously evaluated,
 276                  * evaluate them now and save the results.
 277                  */
 278                 if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
 279                         status = acpi_ds_get_buffer_field_arguments(obj_desc);
 280                         if (ACPI_FAILURE(status)) {
 281                                 return_ACPI_STATUS(status);
 282                         }
 283                 }
 284         } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 285                    (obj_desc->field.region_obj->region.space_id ==
 286                     ACPI_ADR_SPACE_GPIO)) {
 287
 288                 /* General Purpose I/O */
 289
 290                 status = acpi_ex_write_gpio(source_desc, obj_desc, result_desc);
 291                 return_ACPI_STATUS(status);
 292         } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 293                    (obj_desc->field.region_obj->region.space_id ==
 294                     ACPI_ADR_SPACE_SMBUS
 295                     || obj_desc->field.region_obj->region.space_id ==
 296                     ACPI_ADR_SPACE_GSBUS
 297                     || obj_desc->field.region_obj->region.space_id ==
 298                     ACPI_ADR_SPACE_IPMI)) {
 299
 300                 /* SMBus, GSBus, IPMI serial */
 301
 302                 status =
 303                     acpi_ex_write_serial_bus(source_desc, obj_desc,
 304                                              result_desc);
 305                 return_ACPI_STATUS(status);
 306         } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 307                    (obj_desc->field.region_obj->region.space_id ==
 308                     ACPI_ADR_SPACE_PLATFORM_COMM)) {
 309                 /*
 310                  * According to the spec a write to the COMD field will invoke the
 311                  * region handler. Otherwise, write to the pcc_internal buffer. This
 312                  * implementation will use the offsets specified rather than the name
 313                  * of the field. This is considered safer because some firmware tools
 314                  * are known to obfiscate named objects.
 315                  */
 316                 data_length =
 317                     (acpi_size)ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.
 318                                                            bit_length);
 319                 memcpy(obj_desc->field.region_obj->field.internal_pcc_buffer +
 320                        obj_desc->field.base_byte_offset,
 321                        source_desc->buffer.pointer, data_length);
 322
 323                 if ((obj_desc->field.region_obj->region.address ==
 324                      PCC_MASTER_SUBSPACE
 325                      && MASTER_SUBSPACE_COMMAND(obj_desc->field.
 326                                                 base_byte_offset))
 327                     || GENERIC_SUBSPACE_COMMAND(obj_desc->field.
 328                                                 base_byte_offset)) {
 329
 330                         /* Perform the write */
 331
 332                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 333                                           "PCC COMD field has been written. Invoking PCC handler now.\n"));
 334
 335                         status =
 336                             acpi_ex_access_region(obj_desc, 0,
 337                                                   (u64 *)obj_desc->field.
 338                                                   region_obj->field.
 339                                                   internal_pcc_buffer,
 340                                                   ACPI_WRITE);
 341                         return_ACPI_STATUS(status);
 342                 }
 343                 return (AE_OK);
 344         }
 345
 346         /* Get a pointer to the data to be written */
 347
 348         switch (source_desc->common.type) {
 349         case ACPI_TYPE_INTEGER:
 350
 351                 buffer = &source_desc->integer.value;
 352                 buffer_length = sizeof(source_desc->integer.value);
 353                 break;
 354
 355         case ACPI_TYPE_BUFFER:
 356
 357                 buffer = source_desc->buffer.pointer;
 358                 buffer_length = source_desc->buffer.length;
 359                 break;
 360
 361         case ACPI_TYPE_STRING:
 362
 363                 buffer = source_desc->string.pointer;
 364                 buffer_length = source_desc->string.length;
 365                 break;
 366
 367         default:
 368                 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 369         }
 370
 371         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 372                           "FieldWrite [FROM]: Obj %p (%s:%X), Buf %p, ByteLen %X\n",
 373                           source_desc,
 374                           acpi_ut_get_type_name(source_desc->common.type),
 375                           source_desc->common.type, buffer, buffer_length));
 376
 377         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 378                           "FieldWrite [TO]:   Obj %p (%s:%X), BitLen %X, BitOff %X, ByteOff %X\n",
 379                           obj_desc,
 380                           acpi_ut_get_type_name(obj_desc->common.type),
 381                           obj_desc->common.type,
 382                           obj_desc->common_field.bit_length,
 383                           obj_desc->common_field.start_field_bit_offset,
 384                           obj_desc->common_field.base_byte_offset));
 385
 386         /* Lock entire transaction if requested */
 387
 388         acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 389
 390         /* Write to the field */
 391
 392         status = acpi_ex_insert_into_field(obj_desc, buffer, buffer_length);
 393         acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
 394         return_ACPI_STATUS(status);
 395 }