exfldio.c

linux-2.4.29操作系统的源码

	 * index_field - Write to an Index Register, then read/write from/to a Data Register
	 */
	switch (ACPI_GET_OBJECT_TYPE (obj_desc)) {
	case ACPI_TYPE_BUFFER_FIELD:
		/*
		 * 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);
			}
		}

		if (read_write == ACPI_READ) {
			/*
			 * Copy the data from the source buffer.
			 * Length is the field width in bytes.
			 */
			ACPI_MEMCPY (value, (obj_desc->buffer_field.buffer_obj)->buffer.pointer
					  + obj_desc->buffer_field.base_byte_offset
					  + field_datum_byte_offset,
					  obj_desc->common_field.access_byte_width);
		}
		else {
			/*
			 * Copy the data to the target buffer.
			 * Length is the field width in bytes.
			 */
			ACPI_MEMCPY ((obj_desc->buffer_field.buffer_obj)->buffer.pointer
					+ obj_desc->buffer_field.base_byte_offset
					+ field_datum_byte_offset,
					value, obj_desc->common_field.access_byte_width);
		}

		status = AE_OK;
		break;


	case ACPI_TYPE_LOCAL_BANK_FIELD:

		/* Ensure that the bank_value is not beyond the capacity of the register */

		if (acpi_ex_register_overflow (obj_desc->bank_field.bank_obj,
				  (acpi_integer) obj_desc->bank_field.value)) {
			return_ACPI_STATUS (AE_AML_REGISTER_LIMIT);
		}

		/*
		 * For bank_fields, we must write the bank_value to the bank_register
		 * (itself a region_field) before we can access the data.
		 */
		status = acpi_ex_insert_into_field (obj_desc->bank_field.bank_obj,
				 &obj_desc->bank_field.value,
				 sizeof (obj_desc->bank_field.value));
		if (ACPI_FAILURE (status)) {
			return_ACPI_STATUS (status);
		}

		/*
		 * Now that the Bank has been selected, fall through to the
		 * region_field case and write the datum to the Operation Region
		 */

		/*lint -fallthrough */


	case ACPI_TYPE_LOCAL_REGION_FIELD:
		/*
		 * For simple region_fields, we just directly access the owning
		 * Operation Region.
		 */
		status = acpi_ex_access_region (obj_desc, field_datum_byte_offset, value,
				  read_write);
		break;


	case ACPI_TYPE_LOCAL_INDEX_FIELD:


		/* Ensure that the index_value is not beyond the capacity of the register */

		if (acpi_ex_register_overflow (obj_desc->index_field.index_obj,
				  (acpi_integer) obj_desc->index_field.value)) {
			return_ACPI_STATUS (AE_AML_REGISTER_LIMIT);
		}

		/* Write the index value to the index_register (itself a region_field) */

		field_datum_byte_offset += obj_desc->index_field.value;

		ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
				"Write to Index Register: Value %8.8X\n",
				field_datum_byte_offset));

		status = acpi_ex_insert_into_field (obj_desc->index_field.index_obj,
				 &field_datum_byte_offset,
				 sizeof (field_datum_byte_offset));
		if (ACPI_FAILURE (status)) {
			return_ACPI_STATUS (status);
		}

		ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
				"I/O to Data Register: value_ptr %p\n",
				value));

		if (read_write == ACPI_READ) {
			/* Read the datum from the data_register */

			status = acpi_ex_extract_from_field (obj_desc->index_field.data_obj,
					  value, sizeof (acpi_integer));
		}
		else {
			/* Write the datum to the data_register */

			status = acpi_ex_insert_into_field (obj_desc->index_field.data_obj,
					  value, sizeof (acpi_integer));
		}
		break;


	default:

		ACPI_REPORT_ERROR (("Wrong object type in field I/O %X\n",
			ACPI_GET_OBJECT_TYPE (obj_desc)));
		status = AE_AML_INTERNAL;
		break;
	}

	if (ACPI_SUCCESS (status)) {
		if (read_write == ACPI_READ) {
			ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Value Read %8.8X%8.8X, Width %d\n",
					   ACPI_FORMAT_UINT64 (*value),
					   obj_desc->common_field.access_byte_width));
		}
		else {
			ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Value Written %8.8X%8.8X, Width %d\n",
					   ACPI_FORMAT_UINT64 (*value),
					   obj_desc->common_field.access_byte_width));
		}
	}

	return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_write_with_update_rule
 *
 * PARAMETERS:  *obj_desc           - Field to be set
 *              Value               - Value to store
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Apply the field update rule to a field write
 *
 ******************************************************************************/

acpi_status
acpi_ex_write_with_update_rule (
	union acpi_operand_object       *obj_desc,
	acpi_integer                    mask,
	acpi_integer                    field_value,
	u32                             field_datum_byte_offset)
{
	acpi_status                     status = AE_OK;
	acpi_integer                    merged_value;
	acpi_integer                    current_value;


	ACPI_FUNCTION_TRACE_U32 ("ex_write_with_update_rule", mask);


	/* Start with the new bits  */

	merged_value = field_value;

	/* If the mask is all ones, we don't need to worry about the update rule */

	if (mask != ACPI_INTEGER_MAX) {
		/* Decode the update rule */

		switch (obj_desc->common_field.field_flags & AML_FIELD_UPDATE_RULE_MASK) {
		case AML_FIELD_UPDATE_PRESERVE:
			/*
			 * Check if update rule needs to be applied (not if mask is all
			 * ones)  The left shift drops the bits we want to ignore.
			 */
			if ((~mask << (ACPI_MUL_8 (sizeof (mask)) -
					 ACPI_MUL_8 (obj_desc->common_field.access_byte_width))) != 0) {
				/*
				 * Read the current contents of the byte/word/dword containing
				 * the field, and merge with the new field value.
				 */
				status = acpi_ex_field_datum_io (obj_desc, field_datum_byte_offset,
						  &current_value, ACPI_READ);
				if (ACPI_FAILURE (status)) {
					return_ACPI_STATUS (status);
				}

				merged_value |= (current_value & ~mask);
			}
			break;

		case AML_FIELD_UPDATE_WRITE_AS_ONES:

			/* Set positions outside the field to all ones */

			merged_value |= ~mask;
			break;

		case AML_FIELD_UPDATE_WRITE_AS_ZEROS:

			/* Set positions outside the field to all zeros */

			merged_value &= mask;
			break;

		default:

			ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
				"write_with_update_rule: Unknown update_rule setting: %X\n",
				(obj_desc->common_field.field_flags & AML_FIELD_UPDATE_RULE_MASK)));
			return_ACPI_STATUS (AE_AML_OPERAND_VALUE);
		}
	}

	ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
		"Mask %8.8X%8.8X, datum_offset %X, Width %X, Value %8.8X%8.8X, merged_value %8.8X%8.8X\n",
		ACPI_FORMAT_UINT64 (mask),
		field_datum_byte_offset,
		obj_desc->common_field.access_byte_width,
		ACPI_FORMAT_UINT64 (field_value),
		ACPI_FORMAT_UINT64 (merged_value)));

	/* Write the merged value */

	status = acpi_ex_field_datum_io (obj_desc, field_datum_byte_offset,
			  &merged_value, ACPI_WRITE);

	return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_get_buffer_datum
 *
 * PARAMETERS:  Datum               - Where the Datum is returned
 *              Buffer              - Raw field buffer
 *              buffer_length       - Entire length (used for big-endian only)
 *              byte_granularity    - 1/2/4/8 Granularity of the field
 *                                    (aka Datum Size)
 *              buffer_offset       - Datum offset into the buffer
 *
 * RETURN:      none
 *
 * DESCRIPTION: Get a datum from the buffer according to the buffer field
 *              byte granularity
 *
 ******************************************************************************/

void
acpi_ex_get_buffer_datum (
	acpi_integer                    *datum,
	void                            *buffer,
	u32                             buffer_length,
	u32                             byte_granularity,
	u32                             buffer_offset)
{
	u32                             index;


	ACPI_FUNCTION_TRACE_U32 ("ex_get_buffer_datum", byte_granularity);


	/* Get proper index into buffer (handles big/little endian) */

	index = ACPI_BUFFER_INDEX (buffer_length, buffer_offset, byte_granularity);

	/* Move the requested number of bytes */

	switch (byte_granularity) {
	case ACPI_FIELD_BYTE_GRANULARITY:

		*datum = ((u8 *) buffer) [index];
		break;

	case ACPI_FIELD_WORD_GRANULARITY:

		ACPI_MOVE_16_TO_64 (datum, &(((u16 *) buffer) [index]));
		break;

	case ACPI_FIELD_DWORD_GRANULARITY:

		ACPI_MOVE_32_TO_64 (datum, &(((u32 *) buffer) [index]));
		break;

	case ACPI_FIELD_QWORD_GRANULARITY:

		ACPI_MOVE_64_TO_64 (datum, &(((u64 *) buffer) [index]));
		break;

	default:
		/* Should not get here */
		break;
	}

	return_VOID;
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_set_buffer_datum
 *
 * PARAMETERS:  merged_datum        - Value to store
 *              Buffer              - Receiving buffer
 *              buffer_length       - Entire length (used for big-endian only)
 *              byte_granularity    - 1/2/4/8 Granularity of the field
 *                                    (aka Datum Size)
 *              buffer_offset       - Datum offset into the buffer
 *
 * RETURN:      none
 *
 * DESCRIPTION: Store the merged datum to the buffer according to the
 *              byte granularity
 *
 ******************************************************************************/

void
acpi_ex_set_buffer_datum (
	acpi_integer                    merged_datum,
	void                            *buffer,
	u32                             buffer_length,
	u32                             byte_granularity,
	u32                             buffer_offset)
{
	u32                             index;


	ACPI_FUNCTION_TRACE_U32 ("ex_set_buffer_datum", byte_granularity);


	/* Get proper index into buffer (handles big/little endian) */

	index = ACPI_BUFFER_INDEX (buffer_length, buffer_offset, byte_granularity);

	/* Move the requested number of bytes */

	switch (byte_granularity) {
	case ACPI_FIELD_BYTE_GRANULARITY:

		((u8 *) buffer) [index] = (u8) merged_datum;
		break;

	case ACPI_FIELD_WORD_GRANULARITY:

		ACPI_MOVE_64_TO_16 (&(((u16 *) buffer)[index]), &merged_datum);
		break;

	case ACPI_FIELD_DWORD_GRANULARITY:

		ACPI_MOVE_64_TO_32 (&(((u32 *) buffer)[index]), &merged_datum);
		break;

	case ACPI_FIELD_QWORD_GRANULARITY:

		ACPI_MOVE_64_TO_64 (&(((u64 *) buffer)[index]), &merged_datum);
		break;

	default:
		/* Should not get here */
		break;
	}

	return_VOID;
}


/*******************************************************************************
 *