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 - 2022, 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                     || obj_desc->field.region_obj->region.space_id ==
 144                     ACPI_ADR_SPACE_PLATFORM_RT)) {
 145
 146                 /* SMBus, GSBus, IPMI serial */
 147
 148                 status = acpi_ex_read_serial_bus(obj_desc, ret_buffer_desc);
 149                 return_ACPI_STATUS(status);
 150         }
 151
 152         /*
 153          * Allocate a buffer for the contents of the field.
 154          *
 155          * If the field is larger than the current integer width, create
 156          * a BUFFER to hold it. Otherwise, use an INTEGER. This allows
 157          * the use of arithmetic operators on the returned value if the
 158          * field size is equal or smaller than an Integer.
 159          *
 160          * However, all buffer fields created by create_field operator needs to
 161          * remain as a buffer to match other AML interpreter implementations.
 162          *
 163          * Note: Field.length is in bits.
 164          */
 165         buffer_length =
 166             (acpi_size)ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.bit_length);
 167
 168         if (buffer_length > acpi_gbl_integer_byte_width ||
 169             (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD &&
 170              obj_desc->buffer_field.is_create_field)) {
 171
 172                 /* Field is too large for an Integer, create a Buffer instead */
 173
 174                 buffer_desc = acpi_ut_create_buffer_object(buffer_length);
 175                 if (!buffer_desc) {
 176                         return_ACPI_STATUS(AE_NO_MEMORY);
 177                 }
 178                 buffer = buffer_desc->buffer.pointer;
 179         } else {
 180                 /* Field will fit within an Integer (normal case) */
 181
 182                 buffer_desc = acpi_ut_create_integer_object((u64) 0);
 183                 if (!buffer_desc) {
 184                         return_ACPI_STATUS(AE_NO_MEMORY);
 185                 }
 186
 187                 buffer_length = acpi_gbl_integer_byte_width;
 188                 buffer = &buffer_desc->integer.value;
 189         }
 190
 191         if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 192             (obj_desc->field.region_obj->region.space_id ==
 193              ACPI_ADR_SPACE_GPIO)) {
 194
 195                 /* General Purpose I/O */
 196
 197                 status = acpi_ex_read_gpio(obj_desc, buffer);
 198                 goto exit;
 199         } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 200                    (obj_desc->field.region_obj->region.space_id ==
 201                     ACPI_ADR_SPACE_PLATFORM_COMM)) {
 202                 /*
 203                  * Reading from a PCC field unit does not require the handler because
 204                  * it only requires reading from the internal_pcc_buffer.
 205                  */
 206                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 207                                   "PCC FieldRead bits %u\n",
 208                                   obj_desc->field.bit_length));
 209
 210                 memcpy(buffer,
 211                        obj_desc->field.region_obj->field.internal_pcc_buffer +
 212                        obj_desc->field.base_byte_offset,
 213                        (acpi_size)ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.
 214                                                               bit_length));
 215
 216                 *ret_buffer_desc = buffer_desc;
 217                 return AE_OK;
 218         }
 219
 220         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 221                           "FieldRead [TO]:   Obj %p, Type %X, Buf %p, ByteLen %X\n",
 222                           obj_desc, obj_desc->common.type, buffer,
 223                           buffer_length));
 224         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 225                           "FieldRead [FROM]: BitLen %X, BitOff %X, ByteOff %X\n",
 226                           obj_desc->common_field.bit_length,
 227                           obj_desc->common_field.start_field_bit_offset,
 228                           obj_desc->common_field.base_byte_offset));
 229
 230         /* Lock entire transaction if requested */
 231
 232         acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 233
 234         /* Read from the field */
 235
 236         status = acpi_ex_extract_from_field(obj_desc, buffer, buffer_length);
 237         acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
 238
 239 exit:
 240         if (ACPI_FAILURE(status)) {
 241                 acpi_ut_remove_reference(buffer_desc);
 242         } else {
 243                 *ret_buffer_desc = buffer_desc;
 244         }
 245
 246         return_ACPI_STATUS(status);
 247 }
 248
 249 /*******************************************************************************
 250  *
 251  * FUNCTION:    acpi_ex_write_data_to_field
 252  *
 253  * PARAMETERS:  source_desc         - Contains data to write
 254  *              obj_desc            - The named field
 255  *              result_desc         - Where the return value is returned, if any
 256  *
 257  * RETURN:      Status
 258  *
 259  * DESCRIPTION: Write to a named field
 260  *
 261  ******************************************************************************/
 262
 263 acpi_status
 264 acpi_ex_write_data_to_field(union acpi_operand_object *source_desc,
 265                             union acpi_operand_object *obj_desc,
 266                             union acpi_operand_object **result_desc)
 267 {
 268         acpi_status status;
 269         u32 buffer_length;
 270         u32 data_length;
 271         void *buffer;
 272
 273         ACPI_FUNCTION_TRACE_PTR(ex_write_data_to_field, obj_desc);
 274
 275         /* Parameter validation */
 276
 277         if (!source_desc || !obj_desc) {
 278                 return_ACPI_STATUS(AE_AML_NO_OPERAND);
 279         }
 280
 281         if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
 282                 /*
 283                  * If the buffer_field arguments have not been previously evaluated,
 284                  * evaluate them now and save the results.
 285                  */
 286                 if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
 287                         status = acpi_ds_get_buffer_field_arguments(obj_desc);
 288                         if (ACPI_FAILURE(status)) {
 289                                 return_ACPI_STATUS(status);
 290                         }
 291                 }
 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_GPIO)) {
 295
 296                 /* General Purpose I/O */
 297
 298                 status = acpi_ex_write_gpio(source_desc, obj_desc, result_desc);
 299                 return_ACPI_STATUS(status);
 300         } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 301                    (obj_desc->field.region_obj->region.space_id ==
 302                     ACPI_ADR_SPACE_SMBUS
 303                     || obj_desc->field.region_obj->region.space_id ==
 304                     ACPI_ADR_SPACE_GSBUS
 305                     || obj_desc->field.region_obj->region.space_id ==
 306                     ACPI_ADR_SPACE_IPMI
 307                     || obj_desc->field.region_obj->region.space_id ==
 308                     ACPI_ADR_SPACE_PLATFORM_RT)) {
 309
 310                 /* SMBus, GSBus, IPMI serial */
 311
 312                 status =
 313                     acpi_ex_write_serial_bus(source_desc, obj_desc,
 314                                              result_desc);
 315                 return_ACPI_STATUS(status);
 316         } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
 317                    (obj_desc->field.region_obj->region.space_id ==
 318                     ACPI_ADR_SPACE_PLATFORM_COMM)) {
 319                 /*
 320                  * According to the spec a write to the COMD field will invoke the
 321                  * region handler. Otherwise, write to the pcc_internal buffer. This
 322                  * implementation will use the offsets specified rather than the name
 323                  * of the field. This is considered safer because some firmware tools
 324                  * are known to obfiscate named objects.
 325                  */
 326                 data_length =
 327                     (acpi_size)ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.
 328                                                            bit_length);
 329                 memcpy(obj_desc->field.region_obj->field.internal_pcc_buffer +
 330                        obj_desc->field.base_byte_offset,
 331                        source_desc->buffer.pointer, data_length);
 332
 333                 if (MASTER_SUBSPACE_COMMAND(obj_desc->field.base_byte_offset)) {
 334
 335                         /* Perform the write */
 336
 337                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 338                                           "PCC COMD field has been written. Invoking PCC handler now.\n"));
 339
 340                         status =
 341                             acpi_ex_access_region(obj_desc, 0,
 342                                                   (u64 *)obj_desc->field.
 343                                                   region_obj->field.
 344                                                   internal_pcc_buffer,
 345                                                   ACPI_WRITE);
 346                         return_ACPI_STATUS(status);
 347                 }
 348                 return (AE_OK);
 349         }
 350
 351         /* Get a pointer to the data to be written */
 352
 353         switch (source_desc->common.type) {
 354         case ACPI_TYPE_INTEGER:
 355
 356                 buffer = &source_desc->integer.value;
 357                 buffer_length = sizeof(source_desc->integer.value);
 358                 break;
 359
 360         case ACPI_TYPE_BUFFER:
 361
 362                 buffer = source_desc->buffer.pointer;
 363                 buffer_length = source_desc->buffer.length;
 364                 break;
 365
 366         case ACPI_TYPE_STRING:
 367
 368                 buffer = source_desc->string.pointer;
 369                 buffer_length = source_desc->string.length;
 370                 break;
 371
 372         default:
 373                 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 374         }
 375
 376         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 377                           "FieldWrite [FROM]: Obj %p (%s:%X), Buf %p, ByteLen %X\n",
 378                           source_desc,
 379                           acpi_ut_get_type_name(source_desc->common.type),
 380                           source_desc->common.type, buffer, buffer_length));
 381
 382         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 383                           "FieldWrite [TO]:   Obj %p (%s:%X), BitLen %X, BitOff %X, ByteOff %X\n",
 384                           obj_desc,
 385                           acpi_ut_get_type_name(obj_desc->common.type),
 386                           obj_desc->common.type,
 387                           obj_desc->common_field.bit_length,
 388                           obj_desc->common_field.start_field_bit_offset,
 389                           obj_desc->common_field.base_byte_offset));
 390
 391         /* Lock entire transaction if requested */
 392
 393         acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 394
 395         /* Write to the field */
 396
 397         status = acpi_ex_insert_into_field(obj_desc, buffer, buffer_length);
 398         acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
 399         return_ACPI_STATUS(status);
 400 }