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/******************************************************************************
*
* Module Name: exfield - ACPI AML (p-code) execution - field manipulation
* $Revision: 95 $
*
*****************************************************************************/
/*
* Copyright (C) 2000, 2001 R. Byron Moore
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "acpi.h"
#include "acdispat.h"
#include "acinterp.h"
#include "amlcode.h"
#include "acnamesp.h"
#include "achware.h"
#include "acevents.h"
#define _COMPONENT ACPI_EXECUTER
MODULE_NAME ("exfield")
/*******************************************************************************
*
* FUNCTION: Acpi_ex_read_data_from_field
*
* PARAMETERS: Mode - ACPI_READ or ACPI_WRITE
* *Field_node - Parent node for field to be accessed
* *Buffer - Value(s) to be read or written
* Buffer_length - Number of bytes to transfer
*
* RETURN: Status3
*
* DESCRIPTION: Read or write a named field
*
******************************************************************************/
acpi_status
acpi_ex_read_data_from_field (
acpi_operand_object *obj_desc,
acpi_operand_object **ret_buffer_desc)
{
acpi_status status;
acpi_operand_object *buffer_desc;
u32 length;
void *buffer;
FUNCTION_TRACE_PTR ("Ex_read_data_from_field", obj_desc);
/* Parameter validation */
if (!obj_desc) {
return_ACPI_STATUS (AE_AML_NO_OPERAND);
}
/*
* Allocate a buffer for the contents of the field.
*
* If the field is larger than the size of an acpi_integer, create
* a BUFFER to hold it. Otherwise, use an INTEGER. This allows
* the use of arithmetic operators on the returned value if the
* field size is equal or smaller than an Integer.
*
* Note: Field.length is in bits.
*/
length = ROUND_BITS_UP_TO_BYTES (obj_desc->field.bit_length);
if (length > sizeof (acpi_integer)) {
/* Field is too large for an Integer, create a Buffer instead */
buffer_desc = acpi_ut_create_internal_object (ACPI_TYPE_BUFFER);
if (!buffer_desc) {
return_ACPI_STATUS (AE_NO_MEMORY);
}
/* Create the actual read buffer */
buffer_desc->buffer.pointer = ACPI_MEM_CALLOCATE (length);
if (!buffer_desc->buffer.pointer) {
acpi_ut_remove_reference (buffer_desc);
return_ACPI_STATUS (AE_NO_MEMORY);
}
buffer_desc->buffer.length = length;
buffer = buffer_desc->buffer.pointer;
}
else {
/* Field will fit within an Integer (normal case) */
buffer_desc = acpi_ut_create_internal_object (ACPI_TYPE_INTEGER);
if (!buffer_desc) {
return_ACPI_STATUS (AE_NO_MEMORY);
}
length = sizeof (buffer_desc->integer.value);
buffer = &buffer_desc->integer.value;
}
/* Read from the appropriate field */
switch (obj_desc->common.type) {
case ACPI_TYPE_BUFFER_FIELD:
status = acpi_ex_access_buffer_field (ACPI_READ, obj_desc, buffer, length);
break;
case INTERNAL_TYPE_REGION_FIELD:
status = acpi_ex_access_region_field (ACPI_READ, obj_desc, buffer, length);
break;
case INTERNAL_TYPE_BANK_FIELD:
status = acpi_ex_access_bank_field (ACPI_READ, obj_desc, buffer, length);
break;
case INTERNAL_TYPE_INDEX_FIELD:
status = acpi_ex_access_index_field (ACPI_READ, obj_desc, buffer, length);
break;
default:
status = AE_AML_INTERNAL;
}
if (ACPI_FAILURE (status)) {
acpi_ut_remove_reference (buffer_desc);
}
else if (ret_buffer_desc) {
*ret_buffer_desc = buffer_desc;
}
return_ACPI_STATUS (status);
}
/*******************************************************************************
*
* FUNCTION: Acpi_ex_write_data_to_field
*
* PARAMETERS: Mode - ACPI_READ or ACPI_WRITE
* *Field_node - Parent node for field to be accessed
* *Buffer - Value(s) to be read or written
* Buffer_length - Number of bytes to transfer
*
* RETURN: Status
*
* DESCRIPTION: Read or write a named field
*
******************************************************************************/
acpi_status
acpi_ex_write_data_to_field (
acpi_operand_object *source_desc,
acpi_operand_object *obj_desc)
{
acpi_status status;
u32 length;
void *buffer;
FUNCTION_TRACE_PTR ("Ex_write_data_to_field", obj_desc);
/* Parameter validation */
if (!source_desc || !obj_desc) {
return_ACPI_STATUS (AE_AML_NO_OPERAND);
}
/*
* Get a pointer to the data to be written
*/
switch (source_desc->common.type) {
case ACPI_TYPE_INTEGER:
buffer = &source_desc->integer.value;
length = sizeof (source_desc->integer.value);
break;
case ACPI_TYPE_BUFFER:
buffer = source_desc->buffer.pointer;
length = source_desc->buffer.length;
break;
case ACPI_TYPE_STRING:
buffer = source_desc->string.pointer;
length = source_desc->string.length;
break;
default:
return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
}
/*
* Decode the type of field to be written
*/
switch (obj_desc->common.type) {
case ACPI_TYPE_BUFFER_FIELD:
status = acpi_ex_access_buffer_field (ACPI_WRITE, obj_desc, buffer, length);
break;
case INTERNAL_TYPE_REGION_FIELD:
status = acpi_ex_access_region_field (ACPI_WRITE, obj_desc, buffer, length);
break;
case INTERNAL_TYPE_BANK_FIELD:
status = acpi_ex_access_bank_field (ACPI_WRITE, obj_desc, buffer, length);
break;
case INTERNAL_TYPE_INDEX_FIELD:
status = acpi_ex_access_index_field (ACPI_WRITE, obj_desc, buffer, length);
break;
default:
return_ACPI_STATUS (AE_AML_INTERNAL);
}
return_ACPI_STATUS (status);
}
/*******************************************************************************
*
* FUNCTION: Acpi_ex_access_buffer_field
*
* PARAMETERS: Mode - ACPI_READ or ACPI_WRITE
* *Field_node - Parent node for field to be accessed
* *Buffer - Value(s) to be read or written
* Buffer_length - Number of bytes to transfer
*
* RETURN: Status
*
* DESCRIPTION: Read or write a named field
*
******************************************************************************/
acpi_status
acpi_ex_access_buffer_field (
u32 mode,
acpi_operand_object *obj_desc,
void *buffer,
u32 buffer_length)
{
acpi_status status;
FUNCTION_TRACE_PTR ("Ex_access_buffer_field", obj_desc);
/*
* If the Buffer_field arguments have not been previously evaluated,
* evaluate them now and save the results.
*/
if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
status = acpi_ds_get_buffer_field_arguments (obj_desc);
if (ACPI_FAILURE (status)) {
return_ACPI_STATUS (status);
}
}
status = acpi_ex_common_access_field (mode, obj_desc, buffer, buffer_length);
return_ACPI_STATUS (status);
}
/*******************************************************************************
*
* FUNCTION: Acpi_ex_access_region_field
*
* PARAMETERS: Mode - ACPI_READ or ACPI_WRITE
* *Field_node - Parent node for field to be accessed
* *Buffer - Value(s) to be read or written
* Buffer_length - Number of bytes to transfer
*
* RETURN: Status
*
* DESCRIPTION: Read or write a named field
*
******************************************************************************/
acpi_status
acpi_ex_access_region_field (
u32 mode,
acpi_operand_object *obj_desc,
void *buffer,
u32 buffer_length)
{
acpi_status status;
u8 locked;
FUNCTION_TRACE_PTR ("Ex_access_region_field", obj_desc);
/*
* Get the global lock if needed
*/
locked = acpi_ex_acquire_global_lock (obj_desc->field.lock_rule);
status = acpi_ex_common_access_field (mode, obj_desc, buffer, buffer_length);
/*
* Release global lock if we acquired it earlier
*/
acpi_ex_release_global_lock (locked);
return_ACPI_STATUS (status);
}
/*******************************************************************************
*
* FUNCTION: Acpi_ex_access_bank_field
*
* PARAMETERS: Mode - ACPI_READ or ACPI_WRITE
* *Field_node - Parent node for field to be accessed
* *Buffer - Value(s) to be read or written
* Buffer_length - Number of bytes to transfer
*
* RETURN: Status
*
* DESCRIPTION: Read or write a Bank Field
*
******************************************************************************/
acpi_status
acpi_ex_access_bank_field (
u32 mode,
acpi_operand_object *obj_desc,
void *buffer,
u32 buffer_length)
{
acpi_status status;
u8 locked;
FUNCTION_TRACE_PTR ("Ex_access_bank_field", obj_desc);
/*
* Get the global lock if needed
*/
locked = acpi_ex_acquire_global_lock (obj_desc->bank_field.lock_rule);
/*
* Write the Bank_value to the Bank_register to select the bank.
* The Bank_value for this Bank_field is specified in the
* Bank_field ASL declaration. The Bank_register is always a Field in
* an operation region.
*/
status = acpi_ex_common_access_field (ACPI_WRITE,
obj_desc->bank_field.bank_register_obj,
&obj_desc->bank_field.value,
sizeof (obj_desc->bank_field.value));
if (ACPI_FAILURE (status)) {
goto cleanup;
}
/*
* The bank was successfully selected, now read or write the actual
* data.
*/
status = acpi_ex_common_access_field (mode, obj_desc, buffer, buffer_length);
cleanup:
/*
* Release global lock if we acquired it earlier
*/
acpi_ex_release_global_lock (locked);
return_ACPI_STATUS (status);
}
/*******************************************************************************
*
* FUNCTION: Acpi_ex_access_index_field
*
* PARAMETERS: Mode - ACPI_READ or ACPI_WRITE
* *Field_node - Parent node for field to be accessed
* *Buffer - Value(s) to be read or written
* Buffer_length - Number of bytes to transfer
*
* RETURN: Status
*
* DESCRIPTION: Read or write a Index Field
*
******************************************************************************/
acpi_status
acpi_ex_access_index_field (
u32 mode,
acpi_operand_object *obj_desc,
void *buffer,
u32 buffer_length)
{
acpi_status status;
u8 locked;
FUNCTION_TRACE_PTR ("Ex_access_index_field", obj_desc);
/*
* Get the global lock if needed
*/
locked = acpi_ex_acquire_global_lock (obj_desc->index_field.lock_rule);
/*
* Set Index value to select proper Data register
*/
status = acpi_ex_common_access_field (ACPI_WRITE,
obj_desc->index_field.index_obj,
&obj_desc->index_field.value,
sizeof (obj_desc->index_field.value));
if (ACPI_FAILURE (status)) {
goto cleanup;
}
/* Now read/write the data register */
status = acpi_ex_common_access_field (mode, obj_desc->index_field.data_obj,
buffer, buffer_length);
cleanup:
/*
* Release global lock if we acquired it earlier
*/
acpi_ex_release_global_lock (locked);
return_ACPI_STATUS (status);
}
/*******************************************************************************
*
* FUNCTION: Acpi_ex_common_access_field
*
* PARAMETERS: Mode - ACPI_READ or ACPI_WRITE
* *Field_node - Parent node for field to be accessed
* *Buffer - Value(s) to be read or written
* Buffer_length - Size of buffer, in bytes. Must be large
* enough for all bits of the field.
*
* RETURN: Status
*
* DESCRIPTION: Read or write a named field
*
******************************************************************************/
acpi_status
acpi_ex_common_access_field (
u32 mode,
acpi_operand_object *obj_desc,
void *buffer,
u32 buffer_length)
{
acpi_status status;
FUNCTION_TRACE_PTR ("Ex_common_access_field", obj_desc);
ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "Obj=%p Type=%X Buf=%p Len=%X\n",
obj_desc, obj_desc->common.type, buffer, buffer_length));
ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "Mode=%d Bit_len=%X Bit_off=%X Byte_off=%X\n",
mode, obj_desc->common_field.bit_length,
obj_desc->common_field.start_field_bit_offset,
obj_desc->common_field.base_byte_offset));
/* Perform the actual read or write of the field */
switch (mode) {
case ACPI_READ:
status = acpi_ex_extract_from_field (obj_desc, buffer, buffer_length);
break;
case ACPI_WRITE:
status = acpi_ex_insert_into_field (obj_desc, buffer, buffer_length);
break;
default:
ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Unknown I/O Mode: %X\n", mode));
status = AE_BAD_PARAMETER;
break;
}
return_ACPI_STATUS (status);
}
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