/******************************************************************************
*
* Module Name: exprep - ACPI AML (p-code) execution - field prep utilities
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2006, R. Byron Moore
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* substantially similar to the "NO WARRANTY" disclaimer below
* ("Disclaimer") and any redistribution must be conditioned upon
* including a substantially similar Disclaimer requirement for further
* binary redistribution.
* 3. Neither the names of the above-listed copyright holders nor the names
* of any contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGES.
*/
#include <acpi/acpi.h>
#include <acpi/acinterp.h>
#include <acpi/amlcode.h>
#include <acpi/acnamesp.h>
#define _COMPONENT ACPI_EXECUTER
ACPI_MODULE_NAME("exprep")
/* Local prototypes */
static u32
acpi_ex_decode_field_access(union acpi_operand_object *obj_desc,
u8 field_flags, u32 * return_byte_alignment);
#ifdef ACPI_UNDER_DEVELOPMENT
static u32
acpi_ex_generate_access(u32 field_bit_offset,
u32 field_bit_length, u32 region_length);
/*******************************************************************************
*
* FUNCTION: acpi_ex_generate_access
*
* PARAMETERS: field_bit_offset - Start of field within parent region/buffer
* field_bit_length - Length of field in bits
* region_length - Length of parent in bytes
*
* RETURN: Field granularity (8, 16, 32 or 64) and
* byte_alignment (1, 2, 3, or 4)
*
* DESCRIPTION: Generate an optimal access width for fields defined with the
* any_acc keyword.
*
* NOTE: Need to have the region_length in order to check for boundary
* conditions (end-of-region). However, the region_length is a deferred
* operation. Therefore, to complete this implementation, the generation
* of this access width must be deferred until the region length has
* been evaluated.
*
******************************************************************************/
static u32
acpi_ex_generate_access(u32 field_bit_offset,
u32 field_bit_length, u32 region_length)
{
u32 field_byte_length;
u32 field_byte_offset;
u32 field_byte_end_offset;
u32 access_byte_width;
u32 field_start_offset;
u32 field_end_offset;
u32 minimum_access_width = 0xFFFFFFFF;
u32 minimum_accesses = 0xFFFFFFFF;
u32 accesses;
ACPI_FUNCTION_TRACE(ex_generate_access);
/* Round Field start offset and length to "minimal" byte boundaries */
field_byte_offset = ACPI_DIV_8(ACPI_ROUND_DOWN(field_bit_offset, 8));
field_byte_end_offset = ACPI_DIV_8(ACPI_ROUND_UP(field_bit_length +
field_bit_offset, 8));
field_byte_length = field_byte_end_offset - field_byte_offset;
ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
"Bit length %d, Bit offset %d\n",
field_bit_length, field_bit_offset));
ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
"Byte Length %d, Byte Offset %d, End Offset %d\n",
field_byte_length, field_byte_offset,
field_byte_end_offset));
/*
* Iterative search for the maximum access width that is both aligned
* and does not go beyond the end of the region
*
* Start at byte_acc and work upwards to qword_acc max. (1,2,4,8 bytes)
*/
for (access_byte_width = 1; access_byte_width <= 8;
access_byte_width <<= 1) {
/*
* 1) Round end offset up to next access boundary and make sure that
* this does not go beyond the end of the parent region.
* 2) When the Access width is greater than the field_byte_length, we
* are done. (This does not optimize for the perfectly aligned
* case yet).
*/
if (ACPI_ROUND_UP(field_byte_end_offset, access_byte_width) <=
region_length) {
field_start_offset =
ACPI_ROUND_DOWN(field_byte_offset,
access_byte_width) /
access_byte_width;
field_end_offset =
ACPI_ROUND_UP((field_byte_length +
field_byte_offset),
access_byte_width) /
access_byte_width;
accesses = field_end_offset - field_start_offset;
ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
"AccessWidth %d end is within region\n",
access_byte_width));
ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
"Field Start %d, Field End %d -- requires %d accesses\n",
field_start_offset, field_end_offset,
accesses));
/* Single access is optimal */
if (accesses <= 1) {
ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
"Entire field can be accessed with one operation of size %d\n",
access_byte_width));
return_VALUE(access_byte_width);
}
/*
* Fits in the region, but requires more than one read/write.
* try the next wider access on next iteration
*/
if (accesses < minimum_accesses) {
minimum_accesses = accesses;
minimum_access_width = access_byte_width;
}
} else {
ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
"AccessWidth %d end is NOT within region\n",
access_byte_width));
if (access_byte_width == 1) {
ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
"Field goes beyond end-of-region!\n"));
/* Field does not fit in the region at all */
return_VALUE(0);
}
/*
* This width goes beyond the end-of-region, back off to
* previous access
*/
ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
"Backing off to previous optimal access width of %d\n",
minimum_access_width));
return_VALUE(minimum_access_width);
}
}
/*
* Could not read/write field with one operation,
* just use max access width
*/
ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
"Cannot access field in one operation, using width 8\n"));
return_VALUE(8);
}
#endif /* ACPI_UNDER_DEVELOPMENT */
/*******************************************************************************
*
* FUNCTION: acpi_ex_decode_field_access
*
* PARAMETERS: obj_desc - Field object
* field_flags - Encoded fieldflags (contains access bits)
* return_byte_alignment - Where the byte alignment is returned
*
* RETURN: Field granularity (8, 16, 32 or 64) and
* byte_alignment (1, 2, 3, or 4)
*
* DESCRIPTION: Decode the access_type bits of a field definition.
*
******************************************************************************/
static u32
acpi_ex_decode_field_access(union acpi_operand_object *obj_desc,
u8 field_flags, u32 * return_byte_alignment)
{
u32 access;
u32 byte_alignment;
u32 bit_length;
ACPI_FUNCTION_TRACE(ex_decode_field_access);
access = (field_flags & AML_FIELD_ACCESS_TYPE_MASK);
switch (access) {
case AML_FIELD_ACCESS_ANY:
#ifdef ACPI_UNDER_DEVELOPMENT
byte_alignment =
acpi_ex_generate_access(obj_desc->common_field.
start_field_bit_offset,
obj_desc->common_field.bit_length,
0xFFFFFFFF
/* Temp until we pass region_length as parameter */
);
bit_length = byte_alignment * 8;
#endif
byte_alignment = 1;
bit_length = 8;
break;
case AML_FIELD_ACCESS_BYTE:
case AML_FIELD_ACCESS_BUFFER: /* ACPI 2.0 (SMBus Buffer) */
byte_alignment = 1;
bit_length = 8;
break;
case AML_FIELD_ACCESS_WORD:
byte_alignment = 2;
bit_length = 16;
break;
case AML_FIELD_ACCESS_DWORD:
byte_alignment = 4;
bit_length = 32;
break;
case AML_FIELD_ACCESS_QWORD: /* ACPI 2.0 */
byte_alignment = 8;
bit_length = 64;
break;
default:
/* Invalid field access type */
ACPI_ERROR((AE_INFO, "Unknown field access type %X", access));
return_UINT32(0);
}
if (ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_BUFFER_FIELD) {
/*
* buffer_field access can be on any byte boundary, so the
* byte_alignment is always 1 byte -- regardless of any byte_alignment
* implied by the field access type.
*/
byte_alignment = 1;
}
*return_byte_alignment = byte_alignment;
return_UINT32(bit_length);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_prep_common_field_object
*
* PARAMETERS: obj_desc - The field object
* field_flags - Access, lock_rule, and update_rule.
* The format of a field_flag is described
* in the ACPI specification
* field_attribute - Special attributes (not used)
* field_bit_position - Field start position
* field_bit_length - Field length in number of bits
*
* RETURN: Status
*
* DESCRIPTION: Initialize the areas of the field object that are common
* to the various types of fields. Note: This is very "sensitive"
* code because we are solving the general case for field
* alignment.
*
******************************************************************************/
acpi_status
acpi_ex_prep_common_field_object(union acpi_operand_object *obj_desc,
u8 field_flags,
u8 field_attribute,
u32 field_bit_position, u32 field_bit_length)
{
u32 access_bit_width;
u32 byte_alignment;
u32 nearest_byte_address;
ACPI_FUNCTION_TRACE(ex_prep_common_field_object);
/*
* Note: the structure being initialized is the
* ACPI_COMMON_FIELD_INFO; No structure fields outside of the common
* area are initialized by this procedure.
*/
obj_desc->common_field.field_flags = field_flags;
obj_desc->common_field.attribute = field_attribute;
obj_desc->common_field.bit_length = field_bit_length;
/*
* Decode the access type so we can compute offsets. The access type gives
* two pieces of information - the width of each field access and the
* necessary byte_alignment (address granularity) of the access.
*
* For any_acc, the access_bit_width is the largest width that is both
* necessary and possible in an attempt to access the whole field in one
* I/O operation. However, for any_acc, the byte_alignment is always one
* byte.
*
* For all Buffer Fields, the byte_alignment is always one byte.
*
* For all other access types (Byte, Word, Dword, Qword), the Bitwidth is
* the same (equivalent) as the byte_alignment.
*/
access_bit_width = acpi_ex_decode_field_access(obj_desc, field_flags,
&byte_alignment);
if (!access_bit_width) {
return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
}
/* Setup width (access granularity) fields */
obj_desc->common_field.access_byte_width = (u8)
ACPI_DIV_8(access_bit_width); /* 1, 2, 4, 8 */
obj_desc->common_field.access_bit_width = (u8) access_bit_width;
/*
* base_byte_offset is the address of the start of the field within the
* region. It is the byte address of the first *datum* (field-width data
* unit) of the field. (i.e., the first datum that contains at least the
* first *bit* of the field.)
*
* Note: byte_alignment is always either equal to the access_bit_width or 8
* (Byte access), and it defines the addressing granularity of the parent
* region or buffer.
*/
nearest_byte_address =
ACPI_ROUND_BITS_DOWN_TO_BYTES(field_bit_position);
obj_desc->common_field.base_byte_offset = (u32)
ACPI_ROUND_DOWN(nearest_byte_address, byte_alignment);
/*
* start_field_bit_offset is the offset of the first bit of the field within
* a field datum.
*/
obj_desc->common_field.start_field_bit_offset = (u8)
(field_bit_position -
ACPI_MUL_8(obj_desc->common_field.base_byte_offset));
/*
* Does the entire field fit within a single field access element? (datum)
* (i.e., without crossing a datum boundary)
*/
if ((obj_desc->common_field.start_field_bit_offset +
field_bit_length) <= (u16) access_bit_width) {
obj_desc->common.flags |= AOPOBJ_SINGLE_DATUM;
}
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_prep_field_value
*
* PARAMETERS: Info - Contains all field creation info
*
* RETURN: Status
*
* DESCRIPTION: Construct an union acpi_operand_object of type def_field and
* connect it to the parent Node.
*
******************************************************************************/
acpi_status acpi_ex_prep_field_value(struct acpi_create_field_info *info)
{
union acpi_operand_object *obj_desc;
u32 type;
acpi_status status;
ACPI_FUNCTION_TRACE(ex_prep_field_value);
/* Parameter validation */
if (info->field_type != ACPI_TYPE_LOCAL_INDEX_FIELD) {
if (!info->region_node) {
ACPI_ERROR((AE_INFO, "Null RegionNode"));
return_ACPI_STATUS(AE_AML_NO_OPERAND);
}
type = acpi_ns_get_type(info->region_node);
if (type != ACPI_TYPE_REGION) {
ACPI_ERROR((AE_INFO,
"Needed Region, found type %X (%s)",
type, acpi_ut_get_type_name(type)));
return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
}
}
/* Allocate a new field object */
obj_desc = acpi_ut_create_internal_object(info->field_type);
if (!obj_desc) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
/* Initialize areas of the object that are common to all fields */
obj_desc->common_field.node = info->field_node;
status = acpi_ex_prep_common_field_object(obj_desc, info->field_flags,
info->attribute,
info->field_bit_position,
info->field_bit_length);
if (ACPI_FAILURE(status)) {
acpi_ut_delete_object_desc(obj_desc);
return_ACPI_STATUS(status);
}
/* Initialize areas of the object that are specific to the field type */
switch (info->field_type) {
case ACPI_TYPE_LOCAL_REGION_FIELD:
obj_desc->field.region_obj =
acpi_ns_get_attached_object(info->region_node);
/* An additional reference for the container */
acpi_ut_add_reference(obj_desc->field.region_obj);
ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
"RegionField: BitOff %X, Off %X, Gran %X, Region %p\n",
obj_desc->field.start_field_bit_offset,
obj_desc->field.base_byte_offset,
obj_desc->field.access_byte_width,
obj_desc->field.region_obj));
break;
case ACPI_TYPE_LOCAL_BANK_FIELD:
obj_desc->bank_field.value = info->bank_value;
obj_desc->bank_field.region_obj =
acpi_ns_get_attached_object(info->region_node);
obj_desc->bank_field.bank_obj =
acpi_ns_get_attached_object(info->register_node);
/* An additional reference for the attached objects */
acpi_ut_add_reference(obj_desc->bank_field.region_obj);
acpi_ut_add_reference(obj_desc->bank_field.bank_obj);
ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
"Bank Field: BitOff %X, Off %X, Gran %X, Region %p, BankReg %p\n",
obj_desc->bank_field.start_field_bit_offset,
obj_desc->bank_field.base_byte_offset,
obj_desc->field.access_byte_width,
obj_desc->bank_field.region_obj,
obj_desc->bank_field.bank_obj));
break;
case ACPI_TYPE_LOCAL_INDEX_FIELD:
/* Get the Index and Data registers */
obj_desc->index_field.index_obj =
acpi_ns_get_attached_object(info->register_node);
obj_desc->index_field.data_obj =
acpi_ns_get_attached_object(info->data_register_node);
if (!obj_desc->index_field.data_obj
|| !obj_desc->index_field.index_obj) {
ACPI_ERROR((AE_INFO,
"Null Index Object during field prep"));
acpi_ut_delete_object_desc(obj_desc);
return_ACPI_STATUS(AE_AML_INTERNAL);
}
/* An additional reference for the attached objects */
acpi_ut_add_reference(obj_desc->index_field.data_obj);
acpi_ut_add_reference(obj_desc->index_field.index_obj);
/*
* April 2006: Changed to match MS behavior
*
* The value written to the Index register is the byte offset of the
* target field in units of the granularity of the index_field
*
* Previously, the value was calculated as an index in terms of the
* width of the Data register, as below:
*
* obj_desc->index_field.Value = (u32)
* (Info->field_bit_position / ACPI_MUL_8 (
* obj_desc->Field.access_byte_width));
*
* February 2006: Tried value as a byte offset:
* obj_desc->index_field.Value = (u32)
* ACPI_DIV_8 (Info->field_bit_position);
*/
obj_desc->index_field.value =
(u32) ACPI_ROUND_DOWN(ACPI_DIV_8(info->field_bit_position),
obj_desc->index_field.
access_byte_width);
ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
"IndexField: BitOff %X, Off %X, Value %X, Gran %X, Index %p, Data %p\n",
obj_desc->index_field.start_field_bit_offset,
obj_desc->index_field.base_byte_offset,
obj_desc->index_field.value,
obj_desc->field.access_byte_width,
obj_desc->index_field.index_obj,
obj_desc->index_field.data_obj));
break;
default:
/* No other types should get here */
break;
}
/*
* Store the constructed descriptor (obj_desc) into the parent Node,
* preserving the current type of that named_obj.
*/
status = acpi_ns_attach_object(info->field_node, obj_desc,
acpi_ns_get_type(info->field_node));
ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
"Set NamedObj %p [%4.4s], ObjDesc %p\n",
info->field_node,
acpi_ut_get_node_name(info->field_node), obj_desc));
/* Remove local reference to the object */
acpi_ut_remove_reference(obj_desc);
return_ACPI_STATUS(status);
}
