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 }