/******************************************************************************
   *
   * Module Name: evhandler - Support for Address Space handlers
   *
   *****************************************************************************/
  
  /*
   * Copyright (C) 2000 - 2013, Intel Corp.
   * 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 "accommon.h"
  #include "acevents.h"
  #include "acnamesp.h"
  #include "acinterp.h"
  
  #define _COMPONENT          ACPI_EVENTS
  ACPI_MODULE_NAME("evhandler")
  
  /* Local prototypes */
  static acpi_status
  acpi_ev_install_handler(acpi_handle obj_handle,
  			u32 level, void *context, void **return_value);
  
  /* These are the address spaces that will get default handlers */
  
  u8 acpi_gbl_default_address_spaces[ACPI_NUM_DEFAULT_SPACES] = {
  	ACPI_ADR_SPACE_SYSTEM_MEMORY,
  	ACPI_ADR_SPACE_SYSTEM_IO,
  	ACPI_ADR_SPACE_PCI_CONFIG,
  	ACPI_ADR_SPACE_DATA_TABLE
  };
  
  /*******************************************************************************
   *
   * FUNCTION:    acpi_ev_install_region_handlers
   *
   * PARAMETERS:  None
   *
   * RETURN:      Status
   *
   * DESCRIPTION: Installs the core subsystem default address space handlers.
   *
   ******************************************************************************/
  
  acpi_status acpi_ev_install_region_handlers(void)
  {
  	acpi_status status;
  	u32 i;
  
  	ACPI_FUNCTION_TRACE(ev_install_region_handlers);
  
  	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
  	if (ACPI_FAILURE(status)) {
  		return_ACPI_STATUS(status);
  	}
  
  	/*
  	 * All address spaces (PCI Config, EC, SMBus) are scope dependent and
  	 * registration must occur for a specific device.
  	 *
  	 * In the case of the system memory and IO address spaces there is
  	 * currently no device associated with the address space. For these we
  	 * use the root.
  	 *
  	 * We install the default PCI config space handler at the root so that
  	 * this space is immediately available even though the we have not
  	 * enumerated all the PCI Root Buses yet. This is to conform to the ACPI
  	 * specification which states that the PCI config space must be always
  	 * available -- even though we are nowhere near ready to find the PCI root
  	 * buses at this point.
  	 *
  	 * NOTE: We ignore AE_ALREADY_EXISTS because this means that a handler
  	 * has already been installed (via acpi_install_address_space_handler).
  	 * Similar for AE_SAME_HANDLER.
  	 */
  	for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++) {
  		status = acpi_ev_install_space_handler(acpi_gbl_root_node,
  						       acpi_gbl_default_address_spaces
  						       [i],
  						       ACPI_DEFAULT_HANDLER,
  						       NULL, NULL);
  		switch (status) {
  		case AE_OK:
  		case AE_SAME_HANDLER:
  		case AE_ALREADY_EXISTS:
  
  			/* These exceptions are all OK */
  
  			status = AE_OK;
  			break;
  
  		default:
  
  			goto unlock_and_exit;
  		}
  	}
  
  unlock_and_exit:
  	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
  	return_ACPI_STATUS(status);
  }
  
  /*******************************************************************************
   *
   * FUNCTION:    acpi_ev_has_default_handler
   *
   * PARAMETERS:  node                - Namespace node for the device
   *              space_id            - The address space ID
   *
   * RETURN:      TRUE if default handler is installed, FALSE otherwise
   *
   * DESCRIPTION: Check if the default handler is installed for the requested
   *              space ID.
   *
   ******************************************************************************/
  
  u8
  acpi_ev_has_default_handler(struct acpi_namespace_node *node,
  			    acpi_adr_space_type space_id)
  {
  	union acpi_operand_object *obj_desc;
  	union acpi_operand_object *handler_obj;
  
  	/* Must have an existing internal object */
  
  	obj_desc = acpi_ns_get_attached_object(node);
  	if (obj_desc) {
  		handler_obj = obj_desc->device.handler;
  
  		/* Walk the linked list of handlers for this object */
  
  		while (handler_obj) {
  			if (handler_obj->address_space.space_id == space_id) {
  				if (handler_obj->address_space.handler_flags &
  				    ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
  					return (TRUE);
  				}
  			}
  
  			handler_obj = handler_obj->address_space.next;
  		}
  	}
  
  	return (FALSE);
  }
  
  /*******************************************************************************
   *
   * FUNCTION:    acpi_ev_install_handler
   *
   * PARAMETERS:  walk_namespace callback
   *
   * DESCRIPTION: This routine installs an address handler into objects that are
   *              of type Region or Device.
   *
   *              If the Object is a Device, and the device has a handler of
   *              the same type then the search is terminated in that branch.
   *
   *              This is because the existing handler is closer in proximity
   *              to any more regions than the one we are trying to install.
   *
   ******************************************************************************/
  
  static acpi_status
  acpi_ev_install_handler(acpi_handle obj_handle,
  			u32 level, void *context, void **return_value)
  {
  	union acpi_operand_object *handler_obj;
  	union acpi_operand_object *next_handler_obj;
  	union acpi_operand_object *obj_desc;
  	struct acpi_namespace_node *node;
  	acpi_status status;
  
  	ACPI_FUNCTION_NAME(ev_install_handler);
  
  	handler_obj = (union acpi_operand_object *)context;
  
  	/* Parameter validation */
  
  	if (!handler_obj) {
  		return (AE_OK);
  	}
  
  	/* Convert and validate the device handle */
  
  	node = acpi_ns_validate_handle(obj_handle);
  	if (!node) {
  		return (AE_BAD_PARAMETER);
  	}
  
  	/*
  	 * We only care about regions and objects that are allowed to have
  	 * address space handlers
  	 */
  	if ((node->type != ACPI_TYPE_DEVICE) &&
  	    (node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
  		return (AE_OK);
  	}
  
  	/* Check for an existing internal object */
  
  	obj_desc = acpi_ns_get_attached_object(node);
  	if (!obj_desc) {
  
  		/* No object, just exit */
  
  		return (AE_OK);
  	}
  
  	/* Devices are handled different than regions */
  
  	if (obj_desc->common.type == ACPI_TYPE_DEVICE) {
  
  		/* Check if this Device already has a handler for this address space */
  
  		next_handler_obj = obj_desc->device.handler;
  		while (next_handler_obj) {
  
  			/* Found a handler, is it for the same address space? */
  
  			if (next_handler_obj->address_space.space_id ==
  			    handler_obj->address_space.space_id) {
  				ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
  						  "Found handler for region [%s] in device %p(%p) "
  						  "handler %p
  ",
  						  acpi_ut_get_region_name
  						  (handler_obj->address_space.
  						   space_id), obj_desc,
  						  next_handler_obj,
  						  handler_obj));
  
  				/*
  				 * Since the object we found it on was a device, then it
  				 * means that someone has already installed a handler for
  				 * the branch of the namespace from this device on. Just
  				 * bail out telling the walk routine to not traverse this
  				 * branch. This preserves the scoping rule for handlers.
  				 */
  				return (AE_CTRL_DEPTH);
  			}
  
  			/* Walk the linked list of handlers attached to this device */
  
  			next_handler_obj = next_handler_obj->address_space.next;
  		}
  
  		/*
  		 * As long as the device didn't have a handler for this space we
  		 * don't care about it. We just ignore it and proceed.
  		 */
  		return (AE_OK);
  	}
  
  	/* Object is a Region */
  
  	if (obj_desc->region.space_id != handler_obj->address_space.space_id) {
  
  		/* This region is for a different address space, just ignore it */
  
  		return (AE_OK);
  	}
  
  	/*
  	 * Now we have a region and it is for the handler's address space type.
  	 *
  	 * First disconnect region for any previous handler (if any)
  	 */
  	acpi_ev_detach_region(obj_desc, FALSE);
  
  	/* Connect the region to the new handler */
  
  	status = acpi_ev_attach_region(handler_obj, obj_desc, FALSE);
  	return (status);
  }
  
  /*******************************************************************************
   *
   * FUNCTION:    acpi_ev_install_space_handler
   *
   * PARAMETERS:  node            - Namespace node for the device
   *              space_id        - The address space ID
   *              handler         - Address of the handler
   *              setup           - Address of the setup function
   *              context         - Value passed to the handler on each access
   *
   * RETURN:      Status
   *
   * DESCRIPTION: Install a handler for all op_regions of a given space_id.
   *              Assumes namespace is locked
   *
   ******************************************************************************/
  
  acpi_status
  acpi_ev_install_space_handler(struct acpi_namespace_node * node,
  			      acpi_adr_space_type space_id,
  			      acpi_adr_space_handler handler,
  			      acpi_adr_space_setup setup, void *context)
  {
  	union acpi_operand_object *obj_desc;
  	union acpi_operand_object *handler_obj;
  	acpi_status status;
  	acpi_object_type type;
  	u8 flags = 0;
  
  	ACPI_FUNCTION_TRACE(ev_install_space_handler);
  
  	/*
  	 * This registration is valid for only the types below and the root. This
  	 * is where the default handlers get placed.
  	 */
  	if ((node->type != ACPI_TYPE_DEVICE) &&
  	    (node->type != ACPI_TYPE_PROCESSOR) &&
  	    (node->type != ACPI_TYPE_THERMAL) && (node != acpi_gbl_root_node)) {
  		status = AE_BAD_PARAMETER;
  		goto unlock_and_exit;
  	}
  
  	if (handler == ACPI_DEFAULT_HANDLER) {
  		flags = ACPI_ADDR_HANDLER_DEFAULT_INSTALLED;
  
  		switch (space_id) {
  		case ACPI_ADR_SPACE_SYSTEM_MEMORY:
  
  			handler = acpi_ex_system_memory_space_handler;
  			setup = acpi_ev_system_memory_region_setup;
  			break;
  
  		case ACPI_ADR_SPACE_SYSTEM_IO:
  
  			handler = acpi_ex_system_io_space_handler;
  			setup = acpi_ev_io_space_region_setup;
  			break;
  
  		case ACPI_ADR_SPACE_PCI_CONFIG:
  
  			handler = acpi_ex_pci_config_space_handler;
  			setup = acpi_ev_pci_config_region_setup;
  			break;
  
  		case ACPI_ADR_SPACE_CMOS:
  
  			handler = acpi_ex_cmos_space_handler;
  			setup = acpi_ev_cmos_region_setup;
  			break;
  
  		case ACPI_ADR_SPACE_PCI_BAR_TARGET:
  
  			handler = acpi_ex_pci_bar_space_handler;
  			setup = acpi_ev_pci_bar_region_setup;
  			break;
  
  		case ACPI_ADR_SPACE_DATA_TABLE:
  
  			handler = acpi_ex_data_table_space_handler;
  			setup = NULL;
  			break;
  
  		default:
  
  			status = AE_BAD_PARAMETER;
  			goto unlock_and_exit;
  		}
  	}
  
  	/* If the caller hasn't specified a setup routine, use the default */
  
  	if (!setup) {
  		setup = acpi_ev_default_region_setup;
  	}
  
  	/* Check for an existing internal object */
  
  	obj_desc = acpi_ns_get_attached_object(node);
  	if (obj_desc) {
  		/*
  		 * The attached device object already exists. Make sure the handler
  		 * is not already installed.
  		 */
  		handler_obj = obj_desc->device.handler;
  
  		/* Walk the handler list for this device */
  
  		while (handler_obj) {
  
  			/* Same space_id indicates a handler already installed */
  
  			if (handler_obj->address_space.space_id == space_id) {
  				if (handler_obj->address_space.handler ==
  				    handler) {
  					/*
  					 * It is (relatively) OK to attempt to install the SAME
  					 * handler twice. This can easily happen with the
  					 * PCI_Config space.
  					 */
  					status = AE_SAME_HANDLER;
  					goto unlock_and_exit;
  				} else {
  					/* A handler is already installed */
  
  					status = AE_ALREADY_EXISTS;
  				}
  				goto unlock_and_exit;
  			}
  
  			/* Walk the linked list of handlers */
  
  			handler_obj = handler_obj->address_space.next;
  		}
  	} else {
  		ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
  				  "Creating object on Device %p while installing handler
  ",
  				  node));
  
  		/* obj_desc does not exist, create one */
  
  		if (node->type == ACPI_TYPE_ANY) {
  			type = ACPI_TYPE_DEVICE;
  		} else {
  			type = node->type;
  		}
  
  		obj_desc = acpi_ut_create_internal_object(type);
  		if (!obj_desc) {
  			status = AE_NO_MEMORY;
  			goto unlock_and_exit;
  		}
  
  		/* Init new descriptor */
  
  		obj_desc->common.type = (u8)type;
  
  		/* Attach the new object to the Node */
  
  		status = acpi_ns_attach_object(node, obj_desc, type);
  
  		/* Remove local reference to the object */
  
  		acpi_ut_remove_reference(obj_desc);
  
  		if (ACPI_FAILURE(status)) {
  			goto unlock_and_exit;
  		}
  	}
  
  	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
  			  "Installing address handler for region %s(%X) on Device %4.4s %p(%p)
  ",
  			  acpi_ut_get_region_name(space_id), space_id,
  			  acpi_ut_get_node_name(node), node, obj_desc));
  
  	/*
  	 * Install the handler
  	 *
  	 * At this point there is no existing handler. Just allocate the object
  	 * for the handler and link it into the list.
  	 */
  	handler_obj =
  	    acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_ADDRESS_HANDLER);
  	if (!handler_obj) {
  		status = AE_NO_MEMORY;
  		goto unlock_and_exit;
  	}
  
  	/* Init handler obj */
  
  	handler_obj->address_space.space_id = (u8)space_id;
  	handler_obj->address_space.handler_flags = flags;
  	handler_obj->address_space.region_list = NULL;
  	handler_obj->address_space.node = node;
  	handler_obj->address_space.handler = handler;
  	handler_obj->address_space.context = context;
  	handler_obj->address_space.setup = setup;
  
  	/* Install at head of Device.address_space list */
  
  	handler_obj->address_space.next = obj_desc->device.handler;
  
  	/*
  	 * The Device object is the first reference on the handler_obj.
  	 * Each region that uses the handler adds a reference.
  	 */
  	obj_desc->device.handler = handler_obj;
  
  	/*
  	 * Walk the namespace finding all of the regions this
  	 * handler will manage.
  	 *
  	 * Start at the device and search the branch toward
  	 * the leaf nodes until either the leaf is encountered or
  	 * a device is detected that has an address handler of the
  	 * same type.
  	 *
  	 * In either case, back up and search down the remainder
  	 * of the branch
  	 */
  	status = acpi_ns_walk_namespace(ACPI_TYPE_ANY, node, ACPI_UINT32_MAX,
  					ACPI_NS_WALK_UNLOCK,
  					acpi_ev_install_handler, NULL,
  					handler_obj, NULL);
  
  unlock_and_exit:
  	return_ACPI_STATUS(status);
  }