Ejemplo n.º 1
0
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);


    obj_desc->common_field.field_flags = field_flags;
    obj_desc->common_field.attribute = field_attribute;
    obj_desc->common_field.bit_length = field_bit_length;


    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);
    }



    obj_desc->common_field.access_byte_width = (u8)
            ACPI_DIV_8(access_bit_width);

    obj_desc->common_field.access_bit_width = (u8) access_bit_width;


    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);


    obj_desc->common_field.start_field_bit_offset = (u8)
            (field_bit_position -
             ACPI_MUL_8(obj_desc->common_field.base_byte_offset));


    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);
}
Ejemplo n.º 2
0
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));

	return_ACPI_STATUS(AE_OK);
}
Ejemplo n.º 3
0
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 */

	/*
	 * 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 =
			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));

	/*
	 * Valid bits -- the number of bits that compose a partial datum,
	 * 1) At the end of the field within the region (arbitrary starting bit
	 *    offset)
	 * 2) At the end of a buffer used to contain the field (starting offset
	 *    always zero)
	 */
	obj_desc->common_field.end_field_valid_bits = (u8)
		((obj_desc->common_field.start_field_bit_offset + field_bit_length) %
				  access_bit_width);
	/* start_buffer_bit_offset always = 0 */

	obj_desc->common_field.end_buffer_valid_bits = (u8)
		(field_bit_length % access_bit_width);

	/*
	 * datum_valid_bits is the number of valid field bits in the first
	 * field datum.
	 */
	obj_desc->common_field.datum_valid_bits  = (u8)
		(access_bit_width - obj_desc->common_field.start_field_bit_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);
}