1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
4 * Module Name: exfield - AML execution - field_unit read/write
6 * Copyright (C) 2000 - 2019, Intel Corp.
8 *****************************************************************************/
10 #include <acpi/acpi.h>
16 #define _COMPONENT ACPI_EXECUTER
17 ACPI_MODULE_NAME("exfield")
20 * This table maps the various Attrib protocols to the byte transfer
21 * length. Used for the generic serial bus.
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 */
44 #define PCC_MASTER_SUBSPACE 3
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.
52 #define GENERIC_SUBSPACE_COMMAND(a) (4 == a || a == 5)
53 #define MASTER_SUBSPACE_COMMAND(a) (12 <= a && a <= 15)
55 /*******************************************************************************
57 * FUNCTION: acpi_ex_get_protocol_buffer_length
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
64 * RETURN: Status and decoded byte transfer length
66 * DESCRIPTION: This routine returns the length of the generic_serial_bus
69 ******************************************************************************/
72 acpi_ex_get_protocol_buffer_length(u32 protocol_id, u32 *return_length)
75 if ((protocol_id > ACPI_MAX_PROTOCOL_ID) ||
76 (acpi_protocol_lengths[protocol_id] == ACPI_INVALID_PROTOCOL_ID)) {
78 "Invalid Field/AccessAs protocol ID: 0x%4.4X",
81 return (AE_AML_PROTOCOL);
84 *return_length = acpi_protocol_lengths[protocol_id];
88 /*******************************************************************************
90 * FUNCTION: acpi_ex_read_data_from_field
92 * PARAMETERS: walk_state - Current execution state
93 * obj_desc - The named field
94 * ret_buffer_desc - Where the return data object is stored
98 * DESCRIPTION: Read from a named field. Returns either an Integer or a
99 * Buffer, depending on the size of the field.
101 ******************************************************************************/
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)
109 union acpi_operand_object *buffer_desc;
113 ACPI_FUNCTION_TRACE_PTR(ex_read_data_from_field, obj_desc);
115 /* Parameter validation */
118 return_ACPI_STATUS(AE_AML_NO_OPERAND);
120 if (!ret_buffer_desc) {
121 return_ACPI_STATUS(AE_BAD_PARAMETER);
124 if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
126 * If the buffer_field arguments have not been previously evaluated,
127 * evaluate them now and save the results.
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);
135 } else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
136 (obj_desc->field.region_obj->region.space_id ==
138 || obj_desc->field.region_obj->region.space_id ==
140 || obj_desc->field.region_obj->region.space_id ==
141 ACPI_ADR_SPACE_IPMI)) {
143 /* SMBus, GSBus, IPMI serial */
145 status = acpi_ex_read_serial_bus(obj_desc, ret_buffer_desc);
146 return_ACPI_STATUS(status);
150 * Allocate a buffer for the contents of the field.
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.
157 * Note: Field.length is in bits.
160 (acpi_size)ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.bit_length);
162 if (buffer_length > acpi_gbl_integer_byte_width) {
164 /* Field is too large for an Integer, create a Buffer instead */
166 buffer_desc = acpi_ut_create_buffer_object(buffer_length);
168 return_ACPI_STATUS(AE_NO_MEMORY);
170 buffer = buffer_desc->buffer.pointer;
172 /* Field will fit within an Integer (normal case) */
174 buffer_desc = acpi_ut_create_integer_object((u64) 0);
176 return_ACPI_STATUS(AE_NO_MEMORY);
179 buffer_length = acpi_gbl_integer_byte_width;
180 buffer = &buffer_desc->integer.value;
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)) {
187 /* General Purpose I/O */
189 status = acpi_ex_read_gpio(obj_desc, buffer);
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)) {
195 * Reading from a PCC field unit does not require the handler because
196 * it only requires reading from the internal_pcc_buffer.
198 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
199 "PCC FieldRead bits %u\n",
200 obj_desc->field.bit_length));
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.
208 *ret_buffer_desc = buffer_desc;
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,
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));
222 /* Lock entire transaction if requested */
224 acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
226 /* Read from the field */
228 status = acpi_ex_extract_from_field(obj_desc, buffer, buffer_length);
229 acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
232 if (ACPI_FAILURE(status)) {
233 acpi_ut_remove_reference(buffer_desc);
235 *ret_buffer_desc = buffer_desc;
238 return_ACPI_STATUS(status);
241 /*******************************************************************************
243 * FUNCTION: acpi_ex_write_data_to_field
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
251 * DESCRIPTION: Write to a named field
253 ******************************************************************************/
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)
265 ACPI_FUNCTION_TRACE_PTR(ex_write_data_to_field, obj_desc);
267 /* Parameter validation */
269 if (!source_desc || !obj_desc) {
270 return_ACPI_STATUS(AE_AML_NO_OPERAND);
273 if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
275 * If the buffer_field arguments have not been previously evaluated,
276 * evaluate them now and save the results.
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);
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)) {
288 /* General Purpose I/O */
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 ==
295 || obj_desc->field.region_obj->region.space_id ==
297 || obj_desc->field.region_obj->region.space_id ==
298 ACPI_ADR_SPACE_IPMI)) {
300 /* SMBus, GSBus, IPMI serial */
303 acpi_ex_write_serial_bus(source_desc, obj_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)) {
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.
317 (acpi_size)ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.
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);
323 if ((obj_desc->field.region_obj->region.address ==
325 && MASTER_SUBSPACE_COMMAND(obj_desc->field.
327 || GENERIC_SUBSPACE_COMMAND(obj_desc->field.
330 /* Perform the write */
332 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
333 "PCC COMD field has been written. Invoking PCC handler now.\n"));
336 acpi_ex_access_region(obj_desc, 0,
337 (u64 *)obj_desc->field.
341 return_ACPI_STATUS(status);
346 /* Get a pointer to the data to be written */
348 switch (source_desc->common.type) {
349 case ACPI_TYPE_INTEGER:
351 buffer = &source_desc->integer.value;
352 buffer_length = sizeof(source_desc->integer.value);
355 case ACPI_TYPE_BUFFER:
357 buffer = source_desc->buffer.pointer;
358 buffer_length = source_desc->buffer.length;
361 case ACPI_TYPE_STRING:
363 buffer = source_desc->string.pointer;
364 buffer_length = source_desc->string.length;
368 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
371 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
372 "FieldWrite [FROM]: Obj %p (%s:%X), Buf %p, ByteLen %X\n",
374 acpi_ut_get_type_name(source_desc->common.type),
375 source_desc->common.type, buffer, buffer_length));
377 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
378 "FieldWrite [TO]: Obj %p (%s:%X), BitLen %X, BitOff %X, ByteOff %X\n",
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));
386 /* Lock entire transaction if requested */
388 acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
390 /* Write to the field */
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);