drivers/acpi/namespace/nsinit.c

/******************************************************************************
 *
 * Module Name: nsinit - namespace initialization
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2007, 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/acnamesp.h>
#include <acpi/acdispat.h>
#include <acpi/acinterp.h>
#include <linux/nmi.h>

#define _COMPONENT          ACPI_NAMESPACE
ACPI_MODULE_NAME("nsinit")

/* Local prototypes */
static acpi_status
acpi_ns_init_one_object(acpi_handle obj_handle,
			u32 level, void *context, void **return_value);

static acpi_status
acpi_ns_init_one_device(acpi_handle obj_handle,
			u32 nesting_level, void *context, void **return_value);

static acpi_status
acpi_ns_find_ini_methods(acpi_handle obj_handle,
			 u32 nesting_level, void *context, void **return_value);

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_initialize_objects
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Walk the entire namespace and perform any necessary
 *              initialization on the objects found therein
 *
 ******************************************************************************/

acpi_status acpi_ns_initialize_objects(void)
{
	acpi_status status;
	struct acpi_init_walk_info info;

	ACPI_FUNCTION_TRACE(ns_initialize_objects);

	ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
			  "**** Starting initialization of namespace objects ****\n"));
	ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
			      "Completing Region/Field/Buffer/Package initialization:"));

	/* Set all init info to zero */

	ACPI_MEMSET(&info, 0, sizeof(struct acpi_init_walk_info));

	/* Walk entire namespace from the supplied root */

	status = acpi_walk_namespace(ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
				     ACPI_UINT32_MAX, acpi_ns_init_one_object,
				     &info, NULL);
	if (ACPI_FAILURE(status)) {
		ACPI_EXCEPTION((AE_INFO, status, "During WalkNamespace"));
	}

	ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
			      "\nInitialized %hd/%hd Regions %hd/%hd Fields %hd/%hd Buffers %hd/%hd Packages (%hd nodes)\n",
			      info.op_region_init, info.op_region_count,
			      info.field_init, info.field_count,
			      info.buffer_init, info.buffer_count,
			      info.package_init, info.package_count,
			      info.object_count));

	ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
			  "%hd Control Methods found\n", info.method_count));
	ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
			  "%hd Op Regions found\n", info.op_region_count));

	return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_initialize_devices
 *
 * PARAMETERS:  None
 *
 * RETURN:      acpi_status
 *
 * DESCRIPTION: Walk the entire namespace and initialize all ACPI devices.
 *              This means running _INI on all present devices.
 *
 *              Note: We install PCI config space handler on region access,
 *              not here.
 *
 ******************************************************************************/

acpi_status acpi_ns_initialize_devices(void)
{
	acpi_status status;
	struct acpi_device_walk_info info;

	ACPI_FUNCTION_TRACE(ns_initialize_devices);

	/* Init counters */

	info.device_count = 0;
	info.num_STA = 0;
	info.num_INI = 0;

	ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
			      "Initializing Device/Processor/Thermal objects by executing _INI methods:"));

	/* Tree analysis: find all subtrees that contain _INI methods */

	status = acpi_ns_walk_namespace(ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
					ACPI_UINT32_MAX, FALSE,
					acpi_ns_find_ini_methods, &info, NULL);
	if (ACPI_FAILURE(status)) {
		goto error_exit;
	}

	/* Allocate the evaluation information block */

	info.evaluate_info =
	    ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
	if (!info.evaluate_info) {
		status = AE_NO_MEMORY;
		goto error_exit;
	}

	/* Walk namespace to execute all _INIs on present devices */

	status = acpi_ns_walk_namespace(ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
					ACPI_UINT32_MAX, FALSE,
					acpi_ns_init_one_device, &info, NULL);

	ACPI_FREE(info.evaluate_info);
	if (ACPI_FAILURE(status)) {
		goto error_exit;
	}

	ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
			      "\nExecuted %hd _INI methods requiring %hd _STA executions (examined %hd objects)\n",
			      info.num_INI, info.num_STA, info.device_count));

	return_ACPI_STATUS(status);

      error_exit:
	ACPI_EXCEPTION((AE_INFO, status, "During device initialization"));
	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_init_one_object
 *
 * PARAMETERS:  obj_handle      - Node
 *              Level           - Current nesting level
 *              Context         - Points to a init info struct
 *              return_value    - Not used
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Callback from acpi_walk_namespace. Invoked for every object
 *              within the  namespace.
 *
 *              Currently, the only objects that require initialization are:
 *              1) Methods
 *              2) Op Regions
 *
 ******************************************************************************/

static acpi_status
acpi_ns_init_one_object(acpi_handle obj_handle,
			u32 level, void *context, void **return_value)
{
	acpi_object_type type;
	acpi_status status;
	struct acpi_init_walk_info *info =
	    (struct acpi_init_walk_info *)context;
	struct acpi_namespace_node *node =
	    (struct acpi_namespace_node *)obj_handle;
	union acpi_operand_object *obj_desc;

	ACPI_FUNCTION_NAME(ns_init_one_object);

	info->object_count++;

	/* And even then, we are only interested in a few object types */

	type = acpi_ns_get_type(obj_handle);
	obj_desc = acpi_ns_get_attached_object(node);
	if (!obj_desc) {
		return (AE_OK);
	}

	/* Increment counters for object types we are looking for */

	switch (type) {
	case ACPI_TYPE_REGION:
		info->op_region_count++;
		break;

	case ACPI_TYPE_BUFFER_FIELD:
		info->field_count++;
		break;

	case ACPI_TYPE_BUFFER:
		info->buffer_count++;
		break;

	case ACPI_TYPE_PACKAGE:
		info->package_count++;
		break;

	default:

		/* No init required, just exit now */
		return (AE_OK);
	}

	/*
	 * If the object is already initialized, nothing else to do
	 */
	if (obj_desc->common.flags & AOPOBJ_DATA_VALID) {
		return (AE_OK);
	}

	/*
	 * Must lock the interpreter before executing AML code
	 */
	status = acpi_ex_enter_interpreter();
	if (ACPI_FAILURE(status)) {
		return (status);
	}

	/*
	 * Each of these types can contain executable AML code within the
	 * declaration.
	 */
	switch (type) {
	case ACPI_TYPE_REGION:

		info->op_region_init++;
		status = acpi_ds_get_region_arguments(obj_desc);
		break;

	case ACPI_TYPE_BUFFER_FIELD:

		info->field_init++;
		status = acpi_ds_get_buffer_field_arguments(obj_desc);
		break;

	case ACPI_TYPE_BUFFER:

		info->buffer_init++;
		status = acpi_ds_get_buffer_arguments(obj_desc);
		break;

	case ACPI_TYPE_PACKAGE:

		info->package_init++;
		status = acpi_ds_get_package_arguments(obj_desc);
		break;

	default:
		/* No other types can get here */
		break;
	}

	if (ACPI_FAILURE(status)) {
		ACPI_EXCEPTION((AE_INFO, status,
				"Could not execute arguments for [%4.4s] (%s)",
				acpi_ut_get_node_name(node),
				acpi_ut_get_type_name(type)));
	}

	/*
	 * Print a dot for each object unless we are going to print the entire
	 * pathname
	 */
	if (!(acpi_dbg_level & ACPI_LV_INIT_NAMES)) {
		ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT, "."));
	}

	/*
	 * We ignore errors from above, and always return OK, since we don't want
	 * to abort the walk on any single error.
	 */
	acpi_ex_exit_interpreter();
	return (AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_find_ini_methods
 *
 * PARAMETERS:  acpi_walk_callback
 *
 * RETURN:      acpi_status
 *
 * DESCRIPTION: Called during namespace walk. Finds objects named _INI under
 *              device/processor/thermal objects, and marks the entire subtree
 *              with a SUBTREE_HAS_INI flag. This flag is used during the
 *              subsequent device initialization walk to avoid entire subtrees
 *              that do not contain an _INI.
 *
 ******************************************************************************/

static acpi_status
acpi_ns_find_ini_methods(acpi_handle obj_handle,
			 u32 nesting_level, void *context, void **return_value)
{
	struct acpi_device_walk_info *info =
	    ACPI_CAST_PTR(struct acpi_device_walk_info, context);
	struct acpi_namespace_node *node;
	struct acpi_namespace_node *parent_node;

	/* Keep count of device/processor/thermal objects */

	node = ACPI_CAST_PTR(struct acpi_namespace_node, obj_handle);
	if ((node->type == ACPI_TYPE_DEVICE) ||
	    (node->type == ACPI_TYPE_PROCESSOR) ||
	    (node->type == ACPI_TYPE_THERMAL)) {
		info->device_count++;
		return (AE_OK);
	}

	/* We are only looking for methods named _INI */

	if (!ACPI_COMPARE_NAME(node->name.ascii, METHOD_NAME__INI)) {
		return (AE_OK);
	}

	/*
	 * The only _INI methods that we care about are those that are
	 * present under Device, Processor, and Thermal objects.
	 */
	parent_node = acpi_ns_get_parent_node(node);
	switch (parent_node->type) {
	case ACPI_TYPE_DEVICE:
	case ACPI_TYPE_PROCESSOR:
	case ACPI_TYPE_THERMAL:

		/* Mark parent and bubble up the INI present flag to the root */

		while (parent_node) {
			parent_node->flags |= ANOBJ_SUBTREE_HAS_INI;
			parent_node = acpi_ns_get_parent_node(parent_node);
		}
		break;

	default:
		break;
	}

	return (AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_init_one_device
 *
 * PARAMETERS:  acpi_walk_callback
 *
 * RETURN:      acpi_status
 *
 * DESCRIPTION: This is called once per device soon after ACPI is enabled
 *              to initialize each device. It determines if the device is
 *              present, and if so, calls _INI.
 *
 ******************************************************************************/

static acpi_status
acpi_ns_init_one_device(acpi_handle obj_handle,
			u32 nesting_level, void *context, void **return_value)
{
	struct acpi_device_walk_info *walk_info =
	    ACPI_CAST_PTR(struct acpi_device_walk_info, context);
	struct acpi_evaluate_info *info = walk_info->evaluate_info;
	u32 flags;
	acpi_status status;
	struct acpi_namespace_node *device_node;

	ACPI_FUNCTION_TRACE(ns_init_one_device);

	/* We are interested in Devices, Processors and thermal_zones only */

	device_node = ACPI_CAST_PTR(struct acpi_namespace_node, obj_handle);
	if ((device_node->type != ACPI_TYPE_DEVICE) &&
	    (device_node->type != ACPI_TYPE_PROCESSOR) &&
	    (device_node->type != ACPI_TYPE_THERMAL)) {
		return_ACPI_STATUS(AE_OK);
	}

	/*
	 * Because of an earlier namespace analysis, all subtrees that contain an
	 * _INI method are tagged.
	 *
	 * If this device subtree does not contain any _INI methods, we
	 * can exit now and stop traversing this entire subtree.
	 */
	if (!(device_node->flags & ANOBJ_SUBTREE_HAS_INI)) {
		return_ACPI_STATUS(AE_CTRL_DEPTH);
	}

	/*
	 * Run _STA to determine if this device is present and functioning. We
	 * must know this information for two important reasons (from ACPI spec):
	 *
	 * 1) We can only run _INI if the device is present.
	 * 2) We must abort the device tree walk on this subtree if the device is
	 *    not present and is not functional (we will not examine the children)
	 *
	 * The _STA method is not required to be present under the device, we
	 * assume the device is present if _STA does not exist.
	 */
	ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
			(ACPI_TYPE_METHOD, device_node, METHOD_NAME__STA));

	status = acpi_ut_execute_STA(device_node, &flags);
	if (ACPI_FAILURE(status)) {

		/* Ignore error and move on to next device */

		return_ACPI_STATUS(AE_OK);
	}

	/*
	 * Flags == -1 means that _STA was not found. In this case, we assume that
	 * the device is both present and functional.
	 *
	 * From the ACPI spec, description of _STA:
	 *
	 * "If a device object (including the processor object) does not have an
	 * _STA object, then OSPM assumes that all of the above bits are set (in
	 * other words, the device is present, ..., and functioning)"
	 */
	if (flags != ACPI_UINT32_MAX) {
		walk_info->num_STA++;
	}

	/*
	 * Examine the PRESENT and FUNCTIONING status bits
	 *
	 * Note: ACPI spec does not seem to specify behavior for the present but
	 * not functioning case, so we assume functioning if present.
	 */
	if (!(flags & ACPI_STA_DEVICE_PRESENT)) {

		/* Device is not present, we must examine the Functioning bit */

		if (flags & ACPI_STA_DEVICE_FUNCTIONING) {
			/*
			 * Device is not present but is "functioning". In this case,
			 * we will not run _INI, but we continue to examine the children
			 * of this device.
			 *
			 * From the ACPI spec, description of _STA: (Note - no mention
			 * of whether to run _INI or not on the device in question)
			 *
			 * "_STA may return bit 0 clear (not present) with bit 3 set
			 * (device is functional). This case is used to indicate a valid
			 * device for which no device driver should be loaded (for example,
			 * a bridge device.) Children of this device may be present and
			 * valid. OSPM should continue enumeration below a device whose
			 * _STA returns this bit combination"
			 */
			return_ACPI_STATUS(AE_OK);
		} else {
			/*
			 * Device is not present and is not functioning. We must abort the
			 * walk of this subtree immediately -- don't look at the children
			 * of such a device.
			 *
			 * From the ACPI spec, description of _INI:
			 *
			 * "If the _STA method indicates that the device is not present,
			 * OSPM will not run the _INI and will not examine the children
			 * of the device for _INI methods"
			 */
			return_ACPI_STATUS(AE_CTRL_DEPTH);
		}
	}

	/*
	 * The device is present or is assumed present if no _STA exists.
	 * Run the _INI if it exists (not required to exist)
	 *
	 * Note: We know there is an _INI within this subtree, but it may not be
	 * under this particular device, it may be lower in the branch.
	 */
	ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
			(ACPI_TYPE_METHOD, device_node, METHOD_NAME__INI));

	info->prefix_node = device_node;
	info->pathname = METHOD_NAME__INI;
	info->parameters = NULL;
	info->parameter_type = ACPI_PARAM_ARGS;
	info->flags = ACPI_IGNORE_RETURN_VALUE;

	/*
	 * Some hardware relies on this being executed as atomically
	 * as possible (without an NMI being received in the middle of
	 * this) - so disable NMIs and initialize the device:
	 */
	acpi_nmi_disable();
	status = acpi_ns_evaluate(info);
	acpi_nmi_enable();

	if (ACPI_SUCCESS(status)) {
		walk_info->num_INI++;

		if ((acpi_dbg_level <= ACPI_LV_ALL_EXCEPTIONS) &&
		    (!(acpi_dbg_level & ACPI_LV_INFO))) {
			ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT, "."));
		}
	}
#ifdef ACPI_DEBUG_OUTPUT
	else if (status != AE_NOT_FOUND) {

		/* Ignore error and move on to next device */

		char *scope_name =
		    acpi_ns_get_external_pathname(info->resolved_node);

		ACPI_EXCEPTION((AE_INFO, status, "during %s._INI execution",
				scope_name));
		ACPI_FREE(scope_name);
	}
#endif

	/* Ignore errors from above */

	status = AE_OK;

	/*
	 * The _INI method has been run if present; call the Global Initialization
	 * Handler for this device.
	 */
	if (acpi_gbl_init_handler) {
		status =
		    acpi_gbl_init_handler(device_node, ACPI_INIT_DEVICE_INI);
	}

	return_ACPI_STATUS(status);
}