dsopcode.c

linux-2.6.15.6

	ACPI_FUNCTION_TRACE("ds_eval_data_object_operands");

	/* The first operand (for all of these data objects) is the length */

	status = acpi_ds_create_operand(walk_state, op->common.value.arg, 1);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	status = acpi_ex_resolve_operands(walk_state->opcode,
					  &(walk_state->
					    operands[walk_state->num_operands -
						     1]), walk_state);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Extract length operand */

	arg_desc = walk_state->operands[walk_state->num_operands - 1];
	length = (u32) arg_desc->integer.value;

	/* Cleanup for length operand */

	status = acpi_ds_obj_stack_pop(1, walk_state);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	acpi_ut_remove_reference(arg_desc);

	/*
	 * Create the actual data object
	 */
	switch (op->common.aml_opcode) {
	case AML_BUFFER_OP:

		status =
		    acpi_ds_build_internal_buffer_obj(walk_state, op, length,
						      &obj_desc);
		break;

	case AML_PACKAGE_OP:
	case AML_VAR_PACKAGE_OP:

		status =
		    acpi_ds_build_internal_package_obj(walk_state, op, length,
						       &obj_desc);
		break;

	default:
		return_ACPI_STATUS(AE_AML_BAD_OPCODE);
	}

	if (ACPI_SUCCESS(status)) {
		/*
		 * Return the object in the walk_state, unless the parent is a package -
		 * in this case, the return object will be stored in the parse tree
		 * for the package.
		 */
		if ((!op->common.parent) ||
		    ((op->common.parent->common.aml_opcode != AML_PACKAGE_OP) &&
		     (op->common.parent->common.aml_opcode !=
		      AML_VAR_PACKAGE_OP)
		     && (op->common.parent->common.aml_opcode !=
			 AML_NAME_OP))) {
			walk_state->result_obj = obj_desc;
		}
	}

	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_exec_begin_control_op
 *
 * PARAMETERS:  walk_list       - The list that owns the walk stack
 *              Op              - The control Op
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Handles all control ops encountered during control method
 *              execution.
 *
 ******************************************************************************/

acpi_status
acpi_ds_exec_begin_control_op(struct acpi_walk_state *walk_state,
			      union acpi_parse_object *op)
{
	acpi_status status = AE_OK;
	union acpi_generic_state *control_state;

	ACPI_FUNCTION_NAME("ds_exec_begin_control_op");

	ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "Op=%p Opcode=%2.2X State=%p\n", op,
			  op->common.aml_opcode, walk_state));

	switch (op->common.aml_opcode) {
	case AML_IF_OP:
	case AML_WHILE_OP:

		/*
		 * IF/WHILE: Create a new control state to manage these
		 * constructs. We need to manage these as a stack, in order
		 * to handle nesting.
		 */
		control_state = acpi_ut_create_control_state();
		if (!control_state) {
			status = AE_NO_MEMORY;
			break;
		}
		/*
		 * Save a pointer to the predicate for multiple executions
		 * of a loop
		 */
		control_state->control.aml_predicate_start =
		    walk_state->parser_state.aml - 1;
		control_state->control.package_end =
		    walk_state->parser_state.pkg_end;
		control_state->control.opcode = op->common.aml_opcode;

		/* Push the control state on this walk's control stack */

		acpi_ut_push_generic_state(&walk_state->control_state,
					   control_state);
		break;

	case AML_ELSE_OP:

		/* Predicate is in the state object */
		/* If predicate is true, the IF was executed, ignore ELSE part */

		if (walk_state->last_predicate) {
			status = AE_CTRL_TRUE;
		}

		break;

	case AML_RETURN_OP:

		break;

	default:
		break;
	}

	return (status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_exec_end_control_op
 *
 * PARAMETERS:  walk_list       - The list that owns the walk stack
 *              Op              - The control Op
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Handles all control ops encountered during control method
 *              execution.
 *
 ******************************************************************************/

acpi_status
acpi_ds_exec_end_control_op(struct acpi_walk_state * walk_state,
			    union acpi_parse_object * op)
{
	acpi_status status = AE_OK;
	union acpi_generic_state *control_state;

	ACPI_FUNCTION_NAME("ds_exec_end_control_op");

	switch (op->common.aml_opcode) {
	case AML_IF_OP:

		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "[IF_OP] Op=%p\n", op));

		/*
		 * Save the result of the predicate in case there is an
		 * ELSE to come
		 */
		walk_state->last_predicate =
		    (u8) walk_state->control_state->common.value;

		/*
		 * Pop the control state that was created at the start
		 * of the IF and free it
		 */
		control_state =
		    acpi_ut_pop_generic_state(&walk_state->control_state);
		acpi_ut_delete_generic_state(control_state);
		break;

	case AML_ELSE_OP:

		break;

	case AML_WHILE_OP:

		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "[WHILE_OP] Op=%p\n", op));

		if (walk_state->control_state->common.value) {
			/* Predicate was true, go back and evaluate it again! */

			status = AE_CTRL_PENDING;
		}

		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
				  "[WHILE_OP] termination! Op=%p\n", op));

		/* Pop this control state and free it */

		control_state =
		    acpi_ut_pop_generic_state(&walk_state->control_state);

		walk_state->aml_last_while =
		    control_state->control.aml_predicate_start;
		acpi_ut_delete_generic_state(control_state);
		break;

	case AML_RETURN_OP:

		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
				  "[RETURN_OP] Op=%p Arg=%p\n", op,
				  op->common.value.arg));

		/*
		 * One optional operand -- the return value
		 * It can be either an immediate operand or a result that
		 * has been bubbled up the tree
		 */
		if (op->common.value.arg) {
			/* Since we have a real Return(), delete any implicit return */

			acpi_ds_clear_implicit_return(walk_state);

			/* Return statement has an immediate operand */

			status =
			    acpi_ds_create_operands(walk_state,
						    op->common.value.arg);
			if (ACPI_FAILURE(status)) {
				return (status);
			}

			/*
			 * If value being returned is a Reference (such as
			 * an arg or local), resolve it now because it may
			 * cease to exist at the end of the method.
			 */
			status =
			    acpi_ex_resolve_to_value(&walk_state->operands[0],
						     walk_state);
			if (ACPI_FAILURE(status)) {
				return (status);
			}

			/*
			 * Get the return value and save as the last result
			 * value.  This is the only place where walk_state->return_desc
			 * is set to anything other than zero!
			 */
			walk_state->return_desc = walk_state->operands[0];
		} else if ((walk_state->results) &&
			   (walk_state->results->results.num_results > 0)) {
			/* Since we have a real Return(), delete any implicit return */

			acpi_ds_clear_implicit_return(walk_state);

			/*
			 * The return value has come from a previous calculation.
			 *
			 * If value being returned is a Reference (such as
			 * an arg or local), resolve it now because it may
			 * cease to exist at the end of the method.
			 *
			 * Allow references created by the Index operator to return unchanged.
			 */
			if ((ACPI_GET_DESCRIPTOR_TYPE
			     (walk_state->results->results.obj_desc[0]) ==
			     ACPI_DESC_TYPE_OPERAND)
			    &&
			    (ACPI_GET_OBJECT_TYPE
			     (walk_state->results->results.obj_desc[0]) ==
			     ACPI_TYPE_LOCAL_REFERENCE)
			    && ((walk_state->results->results.obj_desc[0])->
				reference.opcode != AML_INDEX_OP)) {
				status =
				    acpi_ex_resolve_to_value(&walk_state->
							     results->results.
							     obj_desc[0],
							     walk_state);
				if (ACPI_FAILURE(status)) {
					return (status);
				}
			}

			walk_state->return_desc =
			    walk_state->results->results.obj_desc[0];
		} else {
			/* No return operand */

			if (walk_state->num_operands) {
				acpi_ut_remove_reference(walk_state->
							 operands[0]);
			}

			walk_state->operands[0] = NULL;
			walk_state->num_operands = 0;
			walk_state->return_desc = NULL;
		}

		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
				  "Completed RETURN_OP State=%p, ret_val=%p\n",
				  walk_state, walk_state->return_desc));

		/* End the control method execution right now */

		status = AE_CTRL_TERMINATE;
		break;

	case AML_NOOP_OP:

		/* Just do nothing! */
		break;

	case AML_BREAK_POINT_OP:

		/* Call up to the OS service layer to handle this */

		status =
		    acpi_os_signal(ACPI_SIGNAL_BREAKPOINT,
				   "Executed AML Breakpoint opcode");

		/* If and when it returns, all done. */

		break;

	case AML_BREAK_OP:
	case AML_CONTINUE_OP:	/* ACPI 2.0 */

		/* Pop and delete control states until we find a while */

		while (walk_state->control_state &&
		       (walk_state->control_state->control.opcode !=
			AML_WHILE_OP)) {
			control_state =
			    acpi_ut_pop_generic_state(&walk_state->
						      control_state);
			acpi_ut_delete_generic_state(control_state);
		}

		/* No while found? */

		if (!walk_state->control_state) {
			return (AE_AML_NO_WHILE);
		}

		/* Was: walk_state->aml_last_while = walk_state->control_state->Control.aml_predicate_start; */

		walk_state->aml_last_while =
		    walk_state->control_state->control.package_end;

		/* Return status depending on opcode */

		if (op->common.aml_opcode == AML_BREAK_OP) {
			status = AE_CTRL_BREAK;
		} else {
			status = AE_CTRL_CONTINUE;
		}
		break;

	default:

		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
				  "Unknown control opcode=%X Op=%p\n",
				  op->common.aml_opcode, op));

		status = AE_AML_BAD_OPCODE;
		break;
	}

	return (status);
}