xref: /openbmc/linux/drivers/acpi/acpica/exfield.c (revision 275876e2)
1 /******************************************************************************
2  *
3  * Module Name: exfield - ACPI AML (p-code) execution - field manipulation
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2014, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acdispat.h"
47 #include "acinterp.h"
48 #include "amlcode.h"
49 
50 #define _COMPONENT          ACPI_EXECUTER
51 ACPI_MODULE_NAME("exfield")
52 
53 /* Local prototypes */
54 static u32
55 acpi_ex_get_serial_access_length(u32 accessor_type, u32 access_length);
56 
57 /*******************************************************************************
58  *
59  * FUNCTION:    acpi_ex_get_serial_access_length
60  *
61  * PARAMETERS:  accessor_type   - The type of the protocol indicated by region
62  *                                field access attributes
63  *              access_length   - The access length of the region field
64  *
65  * RETURN:      Decoded access length
66  *
67  * DESCRIPTION: This routine returns the length of the generic_serial_bus
68  *              protocol bytes
69  *
70  ******************************************************************************/
71 
72 static u32
73 acpi_ex_get_serial_access_length(u32 accessor_type, u32 access_length)
74 {
75 	u32 length;
76 
77 	switch (accessor_type) {
78 	case AML_FIELD_ATTRIB_QUICK:
79 
80 		length = 0;
81 		break;
82 
83 	case AML_FIELD_ATTRIB_SEND_RCV:
84 	case AML_FIELD_ATTRIB_BYTE:
85 
86 		length = 1;
87 		break;
88 
89 	case AML_FIELD_ATTRIB_WORD:
90 	case AML_FIELD_ATTRIB_WORD_CALL:
91 
92 		length = 2;
93 		break;
94 
95 	case AML_FIELD_ATTRIB_MULTIBYTE:
96 	case AML_FIELD_ATTRIB_RAW_BYTES:
97 	case AML_FIELD_ATTRIB_RAW_PROCESS:
98 
99 		length = access_length;
100 		break;
101 
102 	case AML_FIELD_ATTRIB_BLOCK:
103 	case AML_FIELD_ATTRIB_BLOCK_CALL:
104 	default:
105 
106 		length = ACPI_GSBUS_BUFFER_SIZE - 2;
107 		break;
108 	}
109 
110 	return (length);
111 }
112 
113 /*******************************************************************************
114  *
115  * FUNCTION:    acpi_ex_read_data_from_field
116  *
117  * PARAMETERS:  walk_state          - Current execution state
118  *              obj_desc            - The named field
119  *              ret_buffer_desc     - Where the return data object is stored
120  *
121  * RETURN:      Status
122  *
123  * DESCRIPTION: Read from a named field. Returns either an Integer or a
124  *              Buffer, depending on the size of the field.
125  *
126  ******************************************************************************/
127 
128 acpi_status
129 acpi_ex_read_data_from_field(struct acpi_walk_state * walk_state,
130 			     union acpi_operand_object *obj_desc,
131 			     union acpi_operand_object **ret_buffer_desc)
132 {
133 	acpi_status status;
134 	union acpi_operand_object *buffer_desc;
135 	acpi_size length;
136 	void *buffer;
137 	u32 function;
138 	u16 accessor_type;
139 
140 	ACPI_FUNCTION_TRACE_PTR(ex_read_data_from_field, obj_desc);
141 
142 	/* Parameter validation */
143 
144 	if (!obj_desc) {
145 		return_ACPI_STATUS(AE_AML_NO_OPERAND);
146 	}
147 	if (!ret_buffer_desc) {
148 		return_ACPI_STATUS(AE_BAD_PARAMETER);
149 	}
150 
151 	if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
152 		/*
153 		 * If the buffer_field arguments have not been previously evaluated,
154 		 * evaluate them now and save the results.
155 		 */
156 		if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
157 			status = acpi_ds_get_buffer_field_arguments(obj_desc);
158 			if (ACPI_FAILURE(status)) {
159 				return_ACPI_STATUS(status);
160 			}
161 		}
162 	} else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
163 		   (obj_desc->field.region_obj->region.space_id ==
164 		    ACPI_ADR_SPACE_SMBUS
165 		    || obj_desc->field.region_obj->region.space_id ==
166 		    ACPI_ADR_SPACE_GSBUS
167 		    || obj_desc->field.region_obj->region.space_id ==
168 		    ACPI_ADR_SPACE_IPMI)) {
169 		/*
170 		 * This is an SMBus, GSBus or IPMI read. We must create a buffer to hold
171 		 * the data and then directly access the region handler.
172 		 *
173 		 * Note: SMBus and GSBus protocol value is passed in upper 16-bits of Function
174 		 */
175 		if (obj_desc->field.region_obj->region.space_id ==
176 		    ACPI_ADR_SPACE_SMBUS) {
177 			length = ACPI_SMBUS_BUFFER_SIZE;
178 			function =
179 			    ACPI_READ | (obj_desc->field.attribute << 16);
180 		} else if (obj_desc->field.region_obj->region.space_id ==
181 			   ACPI_ADR_SPACE_GSBUS) {
182 			accessor_type = obj_desc->field.attribute;
183 			length = acpi_ex_get_serial_access_length(accessor_type,
184 								  obj_desc->
185 								  field.
186 								  access_length);
187 
188 			/*
189 			 * Add additional 2 bytes for the generic_serial_bus data buffer:
190 			 *
191 			 *     Status;      (Byte 0 of the data buffer)
192 			 *     Length;      (Byte 1 of the data buffer)
193 			 *     Data[x-1];   (Bytes 2-x of the arbitrary length data buffer)
194 			 */
195 			length += 2;
196 			function = ACPI_READ | (accessor_type << 16);
197 		} else {	/* IPMI */
198 
199 			length = ACPI_IPMI_BUFFER_SIZE;
200 			function = ACPI_READ;
201 		}
202 
203 		buffer_desc = acpi_ut_create_buffer_object(length);
204 		if (!buffer_desc) {
205 			return_ACPI_STATUS(AE_NO_MEMORY);
206 		}
207 
208 		/* Lock entire transaction if requested */
209 
210 		acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
211 
212 		/* Call the region handler for the read */
213 
214 		status = acpi_ex_access_region(obj_desc, 0,
215 					       ACPI_CAST_PTR(u64,
216 							     buffer_desc->
217 							     buffer.pointer),
218 					       function);
219 		acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
220 		goto exit;
221 	}
222 
223 	/*
224 	 * Allocate a buffer for the contents of the field.
225 	 *
226 	 * If the field is larger than the current integer width, create
227 	 * a BUFFER to hold it. Otherwise, use an INTEGER. This allows
228 	 * the use of arithmetic operators on the returned value if the
229 	 * field size is equal or smaller than an Integer.
230 	 *
231 	 * Note: Field.length is in bits.
232 	 */
233 	length =
234 	    (acpi_size) ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.bit_length);
235 	if (length > acpi_gbl_integer_byte_width) {
236 
237 		/* Field is too large for an Integer, create a Buffer instead */
238 
239 		buffer_desc = acpi_ut_create_buffer_object(length);
240 		if (!buffer_desc) {
241 			return_ACPI_STATUS(AE_NO_MEMORY);
242 		}
243 		buffer = buffer_desc->buffer.pointer;
244 	} else {
245 		/* Field will fit within an Integer (normal case) */
246 
247 		buffer_desc = acpi_ut_create_integer_object((u64) 0);
248 		if (!buffer_desc) {
249 			return_ACPI_STATUS(AE_NO_MEMORY);
250 		}
251 
252 		length = acpi_gbl_integer_byte_width;
253 		buffer = &buffer_desc->integer.value;
254 	}
255 
256 	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
257 			  "FieldRead [TO]:   Obj %p, Type %X, Buf %p, ByteLen %X\n",
258 			  obj_desc, obj_desc->common.type, buffer,
259 			  (u32) length));
260 	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
261 			  "FieldRead [FROM]: BitLen %X, BitOff %X, ByteOff %X\n",
262 			  obj_desc->common_field.bit_length,
263 			  obj_desc->common_field.start_field_bit_offset,
264 			  obj_desc->common_field.base_byte_offset));
265 
266 	/* Lock entire transaction if requested */
267 
268 	acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
269 
270 	/* Read from the field */
271 
272 	status = acpi_ex_extract_from_field(obj_desc, buffer, (u32) length);
273 	acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
274 
275 exit:
276 	if (ACPI_FAILURE(status)) {
277 		acpi_ut_remove_reference(buffer_desc);
278 	} else {
279 		*ret_buffer_desc = buffer_desc;
280 	}
281 
282 	return_ACPI_STATUS(status);
283 }
284 
285 /*******************************************************************************
286  *
287  * FUNCTION:    acpi_ex_write_data_to_field
288  *
289  * PARAMETERS:  source_desc         - Contains data to write
290  *              obj_desc            - The named field
291  *              result_desc         - Where the return value is returned, if any
292  *
293  * RETURN:      Status
294  *
295  * DESCRIPTION: Write to a named field
296  *
297  ******************************************************************************/
298 
299 acpi_status
300 acpi_ex_write_data_to_field(union acpi_operand_object *source_desc,
301 			    union acpi_operand_object *obj_desc,
302 			    union acpi_operand_object **result_desc)
303 {
304 	acpi_status status;
305 	u32 length;
306 	void *buffer;
307 	union acpi_operand_object *buffer_desc;
308 	u32 function;
309 	u16 accessor_type;
310 
311 	ACPI_FUNCTION_TRACE_PTR(ex_write_data_to_field, obj_desc);
312 
313 	/* Parameter validation */
314 
315 	if (!source_desc || !obj_desc) {
316 		return_ACPI_STATUS(AE_AML_NO_OPERAND);
317 	}
318 
319 	if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
320 		/*
321 		 * If the buffer_field arguments have not been previously evaluated,
322 		 * evaluate them now and save the results.
323 		 */
324 		if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
325 			status = acpi_ds_get_buffer_field_arguments(obj_desc);
326 			if (ACPI_FAILURE(status)) {
327 				return_ACPI_STATUS(status);
328 			}
329 		}
330 	} else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
331 		   (obj_desc->field.region_obj->region.space_id ==
332 		    ACPI_ADR_SPACE_SMBUS
333 		    || obj_desc->field.region_obj->region.space_id ==
334 		    ACPI_ADR_SPACE_GSBUS
335 		    || obj_desc->field.region_obj->region.space_id ==
336 		    ACPI_ADR_SPACE_IPMI)) {
337 		/*
338 		 * This is an SMBus, GSBus or IPMI write. We will bypass the entire field
339 		 * mechanism and handoff the buffer directly to the handler. For
340 		 * these address spaces, the buffer is bi-directional; on a write,
341 		 * return data is returned in the same buffer.
342 		 *
343 		 * Source must be a buffer of sufficient size:
344 		 * ACPI_SMBUS_BUFFER_SIZE, ACPI_GSBUS_BUFFER_SIZE, or ACPI_IPMI_BUFFER_SIZE.
345 		 *
346 		 * Note: SMBus and GSBus protocol type is passed in upper 16-bits of Function
347 		 */
348 		if (source_desc->common.type != ACPI_TYPE_BUFFER) {
349 			ACPI_ERROR((AE_INFO,
350 				    "SMBus/IPMI/GenericSerialBus write requires Buffer, found type %s",
351 				    acpi_ut_get_object_type_name(source_desc)));
352 
353 			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
354 		}
355 
356 		if (obj_desc->field.region_obj->region.space_id ==
357 		    ACPI_ADR_SPACE_SMBUS) {
358 			length = ACPI_SMBUS_BUFFER_SIZE;
359 			function =
360 			    ACPI_WRITE | (obj_desc->field.attribute << 16);
361 		} else if (obj_desc->field.region_obj->region.space_id ==
362 			   ACPI_ADR_SPACE_GSBUS) {
363 			accessor_type = obj_desc->field.attribute;
364 			length = acpi_ex_get_serial_access_length(accessor_type,
365 								  obj_desc->
366 								  field.
367 								  access_length);
368 
369 			/*
370 			 * Add additional 2 bytes for the generic_serial_bus data buffer:
371 			 *
372 			 *     Status;      (Byte 0 of the data buffer)
373 			 *     Length;      (Byte 1 of the data buffer)
374 			 *     Data[x-1];   (Bytes 2-x of the arbitrary length data buffer)
375 			 */
376 			length += 2;
377 			function = ACPI_WRITE | (accessor_type << 16);
378 		} else {	/* IPMI */
379 
380 			length = ACPI_IPMI_BUFFER_SIZE;
381 			function = ACPI_WRITE;
382 		}
383 
384 		if (source_desc->buffer.length < length) {
385 			ACPI_ERROR((AE_INFO,
386 				    "SMBus/IPMI/GenericSerialBus write requires Buffer of length %u, found length %u",
387 				    length, source_desc->buffer.length));
388 
389 			return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
390 		}
391 
392 		/* Create the bi-directional buffer */
393 
394 		buffer_desc = acpi_ut_create_buffer_object(length);
395 		if (!buffer_desc) {
396 			return_ACPI_STATUS(AE_NO_MEMORY);
397 		}
398 
399 		buffer = buffer_desc->buffer.pointer;
400 		ACPI_MEMCPY(buffer, source_desc->buffer.pointer, length);
401 
402 		/* Lock entire transaction if requested */
403 
404 		acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
405 
406 		/*
407 		 * Perform the write (returns status and perhaps data in the
408 		 * same buffer)
409 		 */
410 		status = acpi_ex_access_region(obj_desc, 0,
411 					       (u64 *) buffer, function);
412 		acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
413 
414 		*result_desc = buffer_desc;
415 		return_ACPI_STATUS(status);
416 	}
417 
418 	/* Get a pointer to the data to be written */
419 
420 	switch (source_desc->common.type) {
421 	case ACPI_TYPE_INTEGER:
422 
423 		buffer = &source_desc->integer.value;
424 		length = sizeof(source_desc->integer.value);
425 		break;
426 
427 	case ACPI_TYPE_BUFFER:
428 
429 		buffer = source_desc->buffer.pointer;
430 		length = source_desc->buffer.length;
431 		break;
432 
433 	case ACPI_TYPE_STRING:
434 
435 		buffer = source_desc->string.pointer;
436 		length = source_desc->string.length;
437 		break;
438 
439 	default:
440 
441 		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
442 	}
443 
444 	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
445 			  "FieldWrite [FROM]: Obj %p (%s:%X), Buf %p, ByteLen %X\n",
446 			  source_desc,
447 			  acpi_ut_get_type_name(source_desc->common.type),
448 			  source_desc->common.type, buffer, length));
449 
450 	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
451 			  "FieldWrite [TO]:   Obj %p (%s:%X), BitLen %X, BitOff %X, ByteOff %X\n",
452 			  obj_desc,
453 			  acpi_ut_get_type_name(obj_desc->common.type),
454 			  obj_desc->common.type,
455 			  obj_desc->common_field.bit_length,
456 			  obj_desc->common_field.start_field_bit_offset,
457 			  obj_desc->common_field.base_byte_offset));
458 
459 	/* Lock entire transaction if requested */
460 
461 	acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
462 
463 	/* Write to the field */
464 
465 	status = acpi_ex_insert_into_field(obj_desc, buffer, length);
466 	acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
467 
468 	return_ACPI_STATUS(status);
469 }
470