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
acpi_ex_get_protocol_buffer_length(u32 protocol_id,u32 * return_length)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
acpi_ex_read_data_from_field(struct acpi_walk_state * walk_state,union acpi_operand_object * obj_desc,union acpi_operand_object ** ret_buffer_desc)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
acpi_ex_write_data_to_field(union acpi_operand_object * source_desc,union acpi_operand_object * obj_desc,union acpi_operand_object ** result_desc)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 (MASTER_SUBSPACE_COMMAND(obj_desc->field.base_byte_offset)) {
330
331 /* Perform the write */
332
333 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
334 "PCC COMD field has been written. Invoking PCC handler now.\n"));
335
336 status =
337 acpi_ex_access_region(obj_desc, 0,
338 (u64 *)obj_desc->field.
339 region_obj->field.
340 internal_pcc_buffer,
341 ACPI_WRITE);
342 return_ACPI_STATUS(status);
343 }
344 return (AE_OK);
345 }
346
347 /* Get a pointer to the data to be written */
348
349 switch (source_desc->common.type) {
350 case ACPI_TYPE_INTEGER:
351
352 buffer = &source_desc->integer.value;
353 buffer_length = sizeof(source_desc->integer.value);
354 break;
355
356 case ACPI_TYPE_BUFFER:
357
358 buffer = source_desc->buffer.pointer;
359 buffer_length = source_desc->buffer.length;
360 break;
361
362 case ACPI_TYPE_STRING:
363
364 buffer = source_desc->string.pointer;
365 buffer_length = source_desc->string.length;
366 break;
367
368 default:
369 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
370 }
371
372 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
373 "FieldWrite [FROM]: Obj %p (%s:%X), Buf %p, ByteLen %X\n",
374 source_desc,
375 acpi_ut_get_type_name(source_desc->common.type),
376 source_desc->common.type, buffer, buffer_length));
377
378 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
379 "FieldWrite [TO]: Obj %p (%s:%X), BitLen %X, BitOff %X, ByteOff %X\n",
380 obj_desc,
381 acpi_ut_get_type_name(obj_desc->common.type),
382 obj_desc->common.type,
383 obj_desc->common_field.bit_length,
384 obj_desc->common_field.start_field_bit_offset,
385 obj_desc->common_field.base_byte_offset));
386
387 /* Lock entire transaction if requested */
388
389 acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
390
391 /* Write to the field */
392
393 status = acpi_ex_insert_into_field(obj_desc, buffer, buffer_length);
394 acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
395 return_ACPI_STATUS(status);
396 }
397