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v3.1
  1/******************************************************************************
  2 *
  3 * Module Name: exfield - ACPI AML (p-code) execution - field manipulation
  4 *
  5 *****************************************************************************/
  6
  7/*
  8 * Copyright (C) 2000 - 2011, 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
 49#define _COMPONENT          ACPI_EXECUTER
 50ACPI_MODULE_NAME("exfield")
 51
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 52/*******************************************************************************
 53 *
 54 * FUNCTION:    acpi_ex_read_data_from_field
 55 *
 56 * PARAMETERS:  walk_state          - Current execution state
 57 *              obj_desc            - The named field
 58 *              ret_buffer_desc     - Where the return data object is stored
 59 *
 60 * RETURN:      Status
 61 *
 62 * DESCRIPTION: Read from a named field.  Returns either an Integer or a
 63 *              Buffer, depending on the size of the field.
 64 *
 65 ******************************************************************************/
 
 66acpi_status
 67acpi_ex_read_data_from_field(struct acpi_walk_state *walk_state,
 68			     union acpi_operand_object *obj_desc,
 69			     union acpi_operand_object **ret_buffer_desc)
 70{
 71	acpi_status status;
 72	union acpi_operand_object *buffer_desc;
 73	acpi_size length;
 74	void *buffer;
 75	u32 function;
 
 76
 77	ACPI_FUNCTION_TRACE_PTR(ex_read_data_from_field, obj_desc);
 78
 79	/* Parameter validation */
 80
 81	if (!obj_desc) {
 82		return_ACPI_STATUS(AE_AML_NO_OPERAND);
 83	}
 84	if (!ret_buffer_desc) {
 85		return_ACPI_STATUS(AE_BAD_PARAMETER);
 86	}
 87
 88	if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
 89		/*
 90		 * If the buffer_field arguments have not been previously evaluated,
 91		 * evaluate them now and save the results.
 92		 */
 93		if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
 94			status = acpi_ds_get_buffer_field_arguments(obj_desc);
 95			if (ACPI_FAILURE(status)) {
 96				return_ACPI_STATUS(status);
 97			}
 98		}
 99	} else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
100		   (obj_desc->field.region_obj->region.space_id ==
101		    ACPI_ADR_SPACE_SMBUS
102		    || obj_desc->field.region_obj->region.space_id ==
 
 
103		    ACPI_ADR_SPACE_IPMI)) {
104		/*
105		 * This is an SMBus or IPMI read. We must create a buffer to hold
106		 * the data and then directly access the region handler.
107		 *
108		 * Note: Smbus protocol value is passed in upper 16-bits of Function
109		 */
110		if (obj_desc->field.region_obj->region.space_id ==
111		    ACPI_ADR_SPACE_SMBUS) {
112			length = ACPI_SMBUS_BUFFER_SIZE;
113			function =
114			    ACPI_READ | (obj_desc->field.attribute << 16);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
115		} else {	/* IPMI */
116
117			length = ACPI_IPMI_BUFFER_SIZE;
118			function = ACPI_READ;
119		}
120
121		buffer_desc = acpi_ut_create_buffer_object(length);
122		if (!buffer_desc) {
123			return_ACPI_STATUS(AE_NO_MEMORY);
124		}
125
126		/* Lock entire transaction if requested */
127
128		acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
129
130		/* Call the region handler for the read */
131
132		status = acpi_ex_access_region(obj_desc, 0,
133					       ACPI_CAST_PTR(u64,
134							     buffer_desc->
135							     buffer.pointer),
136					       function);
137		acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
138		goto exit;
139	}
140
141	/*
142	 * Allocate a buffer for the contents of the field.
143	 *
144	 * If the field is larger than the current integer width, create
145	 * a BUFFER to hold it.  Otherwise, use an INTEGER.  This allows
146	 * the use of arithmetic operators on the returned value if the
147	 * field size is equal or smaller than an Integer.
148	 *
149	 * Note: Field.length is in bits.
150	 */
151	length =
152	    (acpi_size) ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.bit_length);
153	if (length > acpi_gbl_integer_byte_width) {
154
155		/* Field is too large for an Integer, create a Buffer instead */
156
157		buffer_desc = acpi_ut_create_buffer_object(length);
158		if (!buffer_desc) {
159			return_ACPI_STATUS(AE_NO_MEMORY);
160		}
161		buffer = buffer_desc->buffer.pointer;
162	} else {
163		/* Field will fit within an Integer (normal case) */
164
165		buffer_desc = acpi_ut_create_integer_object((u64) 0);
166		if (!buffer_desc) {
167			return_ACPI_STATUS(AE_NO_MEMORY);
168		}
169
170		length = acpi_gbl_integer_byte_width;
171		buffer = &buffer_desc->integer.value;
172	}
173
174	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
175			  "FieldRead [TO]:   Obj %p, Type %X, Buf %p, ByteLen %X\n",
176			  obj_desc, obj_desc->common.type, buffer,
177			  (u32) length));
178	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
179			  "FieldRead [FROM]: BitLen %X, BitOff %X, ByteOff %X\n",
180			  obj_desc->common_field.bit_length,
181			  obj_desc->common_field.start_field_bit_offset,
182			  obj_desc->common_field.base_byte_offset));
183
184	/* Lock entire transaction if requested */
185
186	acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
187
188	/* Read from the field */
189
190	status = acpi_ex_extract_from_field(obj_desc, buffer, (u32) length);
191	acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
192
193      exit:
194	if (ACPI_FAILURE(status)) {
195		acpi_ut_remove_reference(buffer_desc);
196	} else {
197		*ret_buffer_desc = buffer_desc;
198	}
199
200	return_ACPI_STATUS(status);
201}
202
203/*******************************************************************************
204 *
205 * FUNCTION:    acpi_ex_write_data_to_field
206 *
207 * PARAMETERS:  source_desc         - Contains data to write
208 *              obj_desc            - The named field
209 *              result_desc         - Where the return value is returned, if any
210 *
211 * RETURN:      Status
212 *
213 * DESCRIPTION: Write to a named field
214 *
215 ******************************************************************************/
216
217acpi_status
218acpi_ex_write_data_to_field(union acpi_operand_object *source_desc,
219			    union acpi_operand_object *obj_desc,
220			    union acpi_operand_object **result_desc)
221{
222	acpi_status status;
223	u32 length;
224	void *buffer;
225	union acpi_operand_object *buffer_desc;
226	u32 function;
 
227
228	ACPI_FUNCTION_TRACE_PTR(ex_write_data_to_field, obj_desc);
229
230	/* Parameter validation */
231
232	if (!source_desc || !obj_desc) {
233		return_ACPI_STATUS(AE_AML_NO_OPERAND);
234	}
235
236	if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
237		/*
238		 * If the buffer_field arguments have not been previously evaluated,
239		 * evaluate them now and save the results.
240		 */
241		if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
242			status = acpi_ds_get_buffer_field_arguments(obj_desc);
243			if (ACPI_FAILURE(status)) {
244				return_ACPI_STATUS(status);
245			}
246		}
247	} else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
248		   (obj_desc->field.region_obj->region.space_id ==
249		    ACPI_ADR_SPACE_SMBUS
250		    || obj_desc->field.region_obj->region.space_id ==
 
 
251		    ACPI_ADR_SPACE_IPMI)) {
252		/*
253		 * This is an SMBus or IPMI write. We will bypass the entire field
254		 * mechanism and handoff the buffer directly to the handler. For
255		 * these address spaces, the buffer is bi-directional; on a write,
256		 * return data is returned in the same buffer.
257		 *
258		 * Source must be a buffer of sufficient size:
259		 * ACPI_SMBUS_BUFFER_SIZE or ACPI_IPMI_BUFFER_SIZE.
260		 *
261		 * Note: SMBus protocol type is passed in upper 16-bits of Function
262		 */
263		if (source_desc->common.type != ACPI_TYPE_BUFFER) {
264			ACPI_ERROR((AE_INFO,
265				    "SMBus or IPMI write requires Buffer, found type %s",
266				    acpi_ut_get_object_type_name(source_desc)));
267
268			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
269		}
270
271		if (obj_desc->field.region_obj->region.space_id ==
272		    ACPI_ADR_SPACE_SMBUS) {
273			length = ACPI_SMBUS_BUFFER_SIZE;
274			function =
275			    ACPI_WRITE | (obj_desc->field.attribute << 16);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
276		} else {	/* IPMI */
277
278			length = ACPI_IPMI_BUFFER_SIZE;
279			function = ACPI_WRITE;
280		}
281
282		if (source_desc->buffer.length < length) {
283			ACPI_ERROR((AE_INFO,
284				    "SMBus or IPMI write requires Buffer of length %u, found length %u",
285				    length, source_desc->buffer.length));
286
287			return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
288		}
289
290		/* Create the bi-directional buffer */
291
292		buffer_desc = acpi_ut_create_buffer_object(length);
293		if (!buffer_desc) {
294			return_ACPI_STATUS(AE_NO_MEMORY);
295		}
296
297		buffer = buffer_desc->buffer.pointer;
298		ACPI_MEMCPY(buffer, source_desc->buffer.pointer, length);
299
300		/* Lock entire transaction if requested */
301
302		acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
303
304		/*
305		 * Perform the write (returns status and perhaps data in the
306		 * same buffer)
307		 */
308		status = acpi_ex_access_region(obj_desc, 0,
309					       (u64 *) buffer, function);
310		acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
311
312		*result_desc = buffer_desc;
313		return_ACPI_STATUS(status);
314	}
315
316	/* Get a pointer to the data to be written */
317
318	switch (source_desc->common.type) {
319	case ACPI_TYPE_INTEGER:
 
320		buffer = &source_desc->integer.value;
321		length = sizeof(source_desc->integer.value);
322		break;
323
324	case ACPI_TYPE_BUFFER:
 
325		buffer = source_desc->buffer.pointer;
326		length = source_desc->buffer.length;
327		break;
328
329	case ACPI_TYPE_STRING:
 
330		buffer = source_desc->string.pointer;
331		length = source_desc->string.length;
332		break;
333
334	default:
 
335		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
336	}
337
338	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
339			  "FieldWrite [FROM]: Obj %p (%s:%X), Buf %p, ByteLen %X\n",
340			  source_desc,
341			  acpi_ut_get_type_name(source_desc->common.type),
342			  source_desc->common.type, buffer, length));
343
344	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
345			  "FieldWrite [TO]:   Obj %p (%s:%X), BitLen %X, BitOff %X, ByteOff %X\n",
346			  obj_desc,
347			  acpi_ut_get_type_name(obj_desc->common.type),
348			  obj_desc->common.type,
349			  obj_desc->common_field.bit_length,
350			  obj_desc->common_field.start_field_bit_offset,
351			  obj_desc->common_field.base_byte_offset));
352
353	/* Lock entire transaction if requested */
354
355	acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
356
357	/* Write to the field */
358
359	status = acpi_ex_insert_into_field(obj_desc, buffer, length);
360	acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
361
362	return_ACPI_STATUS(status);
363}
v3.15
  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
 51ACPI_MODULE_NAME("exfield")
 52
 53/* Local prototypes */
 54static u32
 55acpi_ex_get_serial_access_length(u32 accessor_type, u32 access_length);
 56
 57/*******************************************************************************
 58 *
 59 * FUNCTION:    acpi_get_serial_access_bytes
 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
 72static u32
 73acpi_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;
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
128acpi_status
129acpi_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 modeled generic_serial_bus data buffer:
190			 * typedef struct {
191			 *     BYTEStatus; // Byte 0 of the data buffer
192			 *     BYTELength; // Byte 1 of the data buffer
193			 *     BYTE[x-1]Data; // Bytes 2-x of the arbitrary length data buffer,
194			 * }
195			 */
196			length += 2;
197			function = ACPI_READ | (accessor_type << 16);
198		} else {	/* IPMI */
199
200			length = ACPI_IPMI_BUFFER_SIZE;
201			function = ACPI_READ;
202		}
203
204		buffer_desc = acpi_ut_create_buffer_object(length);
205		if (!buffer_desc) {
206			return_ACPI_STATUS(AE_NO_MEMORY);
207		}
208
209		/* Lock entire transaction if requested */
210
211		acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
212
213		/* Call the region handler for the read */
214
215		status = acpi_ex_access_region(obj_desc, 0,
216					       ACPI_CAST_PTR(u64,
217							     buffer_desc->
218							     buffer.pointer),
219					       function);
220		acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
221		goto exit;
222	}
223
224	/*
225	 * Allocate a buffer for the contents of the field.
226	 *
227	 * If the field is larger than the current integer width, create
228	 * a BUFFER to hold it. Otherwise, use an INTEGER. This allows
229	 * the use of arithmetic operators on the returned value if the
230	 * field size is equal or smaller than an Integer.
231	 *
232	 * Note: Field.length is in bits.
233	 */
234	length =
235	    (acpi_size) ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->field.bit_length);
236	if (length > acpi_gbl_integer_byte_width) {
237
238		/* Field is too large for an Integer, create a Buffer instead */
239
240		buffer_desc = acpi_ut_create_buffer_object(length);
241		if (!buffer_desc) {
242			return_ACPI_STATUS(AE_NO_MEMORY);
243		}
244		buffer = buffer_desc->buffer.pointer;
245	} else {
246		/* Field will fit within an Integer (normal case) */
247
248		buffer_desc = acpi_ut_create_integer_object((u64) 0);
249		if (!buffer_desc) {
250			return_ACPI_STATUS(AE_NO_MEMORY);
251		}
252
253		length = acpi_gbl_integer_byte_width;
254		buffer = &buffer_desc->integer.value;
255	}
256
257	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
258			  "FieldRead [TO]:   Obj %p, Type %X, Buf %p, ByteLen %X\n",
259			  obj_desc, obj_desc->common.type, buffer,
260			  (u32) length));
261	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
262			  "FieldRead [FROM]: BitLen %X, BitOff %X, ByteOff %X\n",
263			  obj_desc->common_field.bit_length,
264			  obj_desc->common_field.start_field_bit_offset,
265			  obj_desc->common_field.base_byte_offset));
266
267	/* Lock entire transaction if requested */
268
269	acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
270
271	/* Read from the field */
272
273	status = acpi_ex_extract_from_field(obj_desc, buffer, (u32) length);
274	acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
275
276exit:
277	if (ACPI_FAILURE(status)) {
278		acpi_ut_remove_reference(buffer_desc);
279	} else {
280		*ret_buffer_desc = buffer_desc;
281	}
282
283	return_ACPI_STATUS(status);
284}
285
286/*******************************************************************************
287 *
288 * FUNCTION:    acpi_ex_write_data_to_field
289 *
290 * PARAMETERS:  source_desc         - Contains data to write
291 *              obj_desc            - The named field
292 *              result_desc         - Where the return value is returned, if any
293 *
294 * RETURN:      Status
295 *
296 * DESCRIPTION: Write to a named field
297 *
298 ******************************************************************************/
299
300acpi_status
301acpi_ex_write_data_to_field(union acpi_operand_object *source_desc,
302			    union acpi_operand_object *obj_desc,
303			    union acpi_operand_object **result_desc)
304{
305	acpi_status status;
306	u32 length;
307	void *buffer;
308	union acpi_operand_object *buffer_desc;
309	u32 function;
310	u16 accessor_type;
311
312	ACPI_FUNCTION_TRACE_PTR(ex_write_data_to_field, obj_desc);
313
314	/* Parameter validation */
315
316	if (!source_desc || !obj_desc) {
317		return_ACPI_STATUS(AE_AML_NO_OPERAND);
318	}
319
320	if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
321		/*
322		 * If the buffer_field arguments have not been previously evaluated,
323		 * evaluate them now and save the results.
324		 */
325		if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
326			status = acpi_ds_get_buffer_field_arguments(obj_desc);
327			if (ACPI_FAILURE(status)) {
328				return_ACPI_STATUS(status);
329			}
330		}
331	} else if ((obj_desc->common.type == ACPI_TYPE_LOCAL_REGION_FIELD) &&
332		   (obj_desc->field.region_obj->region.space_id ==
333		    ACPI_ADR_SPACE_SMBUS
334		    || obj_desc->field.region_obj->region.space_id ==
335		    ACPI_ADR_SPACE_GSBUS
336		    || obj_desc->field.region_obj->region.space_id ==
337		    ACPI_ADR_SPACE_IPMI)) {
338		/*
339		 * This is an SMBus, GSBus or IPMI write. We will bypass the entire field
340		 * mechanism and handoff the buffer directly to the handler. For
341		 * these address spaces, the buffer is bi-directional; on a write,
342		 * return data is returned in the same buffer.
343		 *
344		 * Source must be a buffer of sufficient size:
345		 * ACPI_SMBUS_BUFFER_SIZE, ACPI_GSBUS_BUFFER_SIZE, or ACPI_IPMI_BUFFER_SIZE.
346		 *
347		 * Note: SMBus and GSBus protocol type is passed in upper 16-bits of Function
348		 */
349		if (source_desc->common.type != ACPI_TYPE_BUFFER) {
350			ACPI_ERROR((AE_INFO,
351				    "SMBus/IPMI/GenericSerialBus write requires Buffer, found type %s",
352				    acpi_ut_get_object_type_name(source_desc)));
353
354			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
355		}
356
357		if (obj_desc->field.region_obj->region.space_id ==
358		    ACPI_ADR_SPACE_SMBUS) {
359			length = ACPI_SMBUS_BUFFER_SIZE;
360			function =
361			    ACPI_WRITE | (obj_desc->field.attribute << 16);
362		} else if (obj_desc->field.region_obj->region.space_id ==
363			   ACPI_ADR_SPACE_GSBUS) {
364			accessor_type = obj_desc->field.attribute;
365			length = acpi_ex_get_serial_access_length(accessor_type,
366								  obj_desc->
367								  field.
368								  access_length);
369
370			/*
371			 * Add additional 2 bytes for modeled generic_serial_bus data buffer:
372			 * typedef struct {
373			 *     BYTEStatus; // Byte 0 of the data buffer
374			 *     BYTELength; // Byte 1 of the data buffer
375			 *     BYTE[x-1]Data; // Bytes 2-x of the arbitrary length data buffer,
376			 * }
377			 */
378			length += 2;
379			function = ACPI_WRITE | (accessor_type << 16);
380		} else {	/* IPMI */
381
382			length = ACPI_IPMI_BUFFER_SIZE;
383			function = ACPI_WRITE;
384		}
385
386		if (source_desc->buffer.length < length) {
387			ACPI_ERROR((AE_INFO,
388				    "SMBus/IPMI/GenericSerialBus write requires Buffer of length %u, found length %u",
389				    length, source_desc->buffer.length));
390
391			return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
392		}
393
394		/* Create the bi-directional buffer */
395
396		buffer_desc = acpi_ut_create_buffer_object(length);
397		if (!buffer_desc) {
398			return_ACPI_STATUS(AE_NO_MEMORY);
399		}
400
401		buffer = buffer_desc->buffer.pointer;
402		ACPI_MEMCPY(buffer, source_desc->buffer.pointer, length);
403
404		/* Lock entire transaction if requested */
405
406		acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
407
408		/*
409		 * Perform the write (returns status and perhaps data in the
410		 * same buffer)
411		 */
412		status = acpi_ex_access_region(obj_desc, 0,
413					       (u64 *) buffer, function);
414		acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
415
416		*result_desc = buffer_desc;
417		return_ACPI_STATUS(status);
418	}
419
420	/* Get a pointer to the data to be written */
421
422	switch (source_desc->common.type) {
423	case ACPI_TYPE_INTEGER:
424
425		buffer = &source_desc->integer.value;
426		length = sizeof(source_desc->integer.value);
427		break;
428
429	case ACPI_TYPE_BUFFER:
430
431		buffer = source_desc->buffer.pointer;
432		length = source_desc->buffer.length;
433		break;
434
435	case ACPI_TYPE_STRING:
436
437		buffer = source_desc->string.pointer;
438		length = source_desc->string.length;
439		break;
440
441	default:
442
443		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
444	}
445
446	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
447			  "FieldWrite [FROM]: Obj %p (%s:%X), Buf %p, ByteLen %X\n",
448			  source_desc,
449			  acpi_ut_get_type_name(source_desc->common.type),
450			  source_desc->common.type, buffer, length));
451
452	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
453			  "FieldWrite [TO]:   Obj %p (%s:%X), BitLen %X, BitOff %X, ByteOff %X\n",
454			  obj_desc,
455			  acpi_ut_get_type_name(obj_desc->common.type),
456			  obj_desc->common.type,
457			  obj_desc->common_field.bit_length,
458			  obj_desc->common_field.start_field_bit_offset,
459			  obj_desc->common_field.base_byte_offset));
460
461	/* Lock entire transaction if requested */
462
463	acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
464
465	/* Write to the field */
466
467	status = acpi_ex_insert_into_field(obj_desc, buffer, length);
468	acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
469
470	return_ACPI_STATUS(status);
471}