efi_boottime.c

	/* Create new handle if requested. */
	if (!*handle) {
		r = efi_create_handle(handle);
		if (r != EFI_SUCCESS)
			goto out;
		debug("%sEFI: new handle %p\n", indent_string(nesting_level),
		      *handle);
	} else {
		debug("%sEFI: handle %p\n", indent_string(nesting_level),
		      *handle);
	}
	/* Add new protocol */
	r = efi_add_protocol(*handle, protocol, protocol_interface);
out:
	return EFI_EXIT(r);
}

/*
 * Reinstall protocol interface.
 *
 * This function implements the ReinstallProtocolInterface service.
 * See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @handle			handle on which the protocol shall be
 *				reinstalled
 * @protocol			GUID of the protocol to be installed
 * @old_interface		interface to be removed
 * @new_interface		interface to be installed
 * @return			status code
 */
static efi_status_t EFIAPI efi_reinstall_protocol_interface(
			efi_handle_t handle, const efi_guid_t *protocol,
			void *old_interface, void *new_interface)
{
	EFI_ENTRY("%p, %pUl, %p, %p", handle, protocol, old_interface,
		  new_interface);
	return EFI_EXIT(EFI_ACCESS_DENIED);
}

/*
 * Get all drivers associated to a controller.
 * The allocated buffer has to be freed with free().
 *
 * @efiobj			handle of the controller
 * @protocol			protocol guid (optional)
 * @number_of_drivers		number of child controllers
 * @driver_handle_buffer	handles of the the drivers
 * @return			status code
 */
static efi_status_t efi_get_drivers(struct efi_object *efiobj,
				    const efi_guid_t *protocol,
				    efi_uintn_t *number_of_drivers,
				    efi_handle_t **driver_handle_buffer)
{
	struct efi_handler *handler;
	struct efi_open_protocol_info_item *item;
	efi_uintn_t count = 0, i;
	bool duplicate;

	/* Count all driver associations */
	list_for_each_entry(handler, &efiobj->protocols, link) {
		if (protocol && guidcmp(handler->guid, protocol))
			continue;
		list_for_each_entry(item, &handler->open_infos, link) {
			if (item->info.attributes &
			    EFI_OPEN_PROTOCOL_BY_DRIVER)
				++count;
		}
	}
	/*
	 * Create buffer. In case of duplicate driver assignments the buffer
	 * will be too large. But that does not harm.
	 */
	*number_of_drivers = 0;
	*driver_handle_buffer = calloc(count, sizeof(efi_handle_t));
	if (!*driver_handle_buffer)
		return EFI_OUT_OF_RESOURCES;
	/* Collect unique driver handles */
	list_for_each_entry(handler, &efiobj->protocols, link) {
		if (protocol && guidcmp(handler->guid, protocol))
			continue;
		list_for_each_entry(item, &handler->open_infos, link) {
			if (item->info.attributes &
			    EFI_OPEN_PROTOCOL_BY_DRIVER) {
				/* Check this is a new driver */
				duplicate = false;
				for (i = 0; i < *number_of_drivers; ++i) {
					if ((*driver_handle_buffer)[i] ==
					    item->info.agent_handle)
						duplicate = true;
				}
				/* Copy handle to buffer */
				if (!duplicate) {
					i = (*number_of_drivers)++;
					(*driver_handle_buffer)[i] =
						item->info.agent_handle;
				}
			}
		}
	}
	return EFI_SUCCESS;
}

/*
 * Disconnect all drivers from a controller.
 *
 * This function implements the DisconnectController service.
 * See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @efiobj		handle of the controller
 * @protocol		protocol guid (optional)
 * @child_handle	handle of the child to destroy
 * @return		status code
 */
static efi_status_t efi_disconnect_all_drivers(
				struct efi_object *efiobj,
				const efi_guid_t *protocol,
				efi_handle_t child_handle)
{
	efi_uintn_t number_of_drivers;
	efi_handle_t *driver_handle_buffer;
	efi_status_t r, ret;

	ret = efi_get_drivers(efiobj, protocol, &number_of_drivers,
			      &driver_handle_buffer);
	if (ret != EFI_SUCCESS)
		return ret;

	ret = EFI_NOT_FOUND;
	while (number_of_drivers) {
		r = EFI_CALL(efi_disconnect_controller(
				efiobj->handle,
				driver_handle_buffer[--number_of_drivers],
				child_handle));
		if (r == EFI_SUCCESS)
			ret = r;
	}
	free(driver_handle_buffer);
	return ret;
}

/*
 * Uninstall protocol interface.
 *
 * This function implements the UninstallProtocolInterface service.
 * See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @handle			handle from which the protocol shall be removed
 * @protocol			GUID of the protocol to be removed
 * @protocol_interface		interface to be removed
 * @return			status code
 */
static efi_status_t EFIAPI efi_uninstall_protocol_interface(
				efi_handle_t handle, const efi_guid_t *protocol,
				void *protocol_interface)
{
	struct efi_object *efiobj;
	struct efi_handler *handler;
	struct efi_open_protocol_info_item *item;
	struct efi_open_protocol_info_item *pos;
	efi_status_t r;

	EFI_ENTRY("%p, %pUl, %p", handle, protocol, protocol_interface);

	/* Check handle */
	efiobj = efi_search_obj(handle);
	if (!efiobj) {
		r = EFI_INVALID_PARAMETER;
		goto out;
	}
	/* Find the protocol on the handle */
	r = efi_search_protocol(handle, protocol, &handler);
	if (r != EFI_SUCCESS)
		goto out;
	/* Disconnect controllers */
	efi_disconnect_all_drivers(efiobj, protocol, NULL);
	if (!list_empty(&handler->open_infos)) {
		r =  EFI_ACCESS_DENIED;
		goto out;
	}
	/* Close protocol */
	list_for_each_entry_safe(item, pos, &handler->open_infos, link) {
		if (item->info.attributes ==
			EFI_OPEN_PROTOCOL_BY_HANDLE_PROTOCOL ||
		    item->info.attributes == EFI_OPEN_PROTOCOL_GET_PROTOCOL ||
		    item->info.attributes == EFI_OPEN_PROTOCOL_TEST_PROTOCOL)
			list_del(&item->link);
	}
	if (!list_empty(&handler->open_infos)) {
		r =  EFI_ACCESS_DENIED;
		goto out;
	}
	r = efi_remove_protocol(handle, protocol, protocol_interface);
out:
	return EFI_EXIT(r);
}

/*
 * Register an event for notification when a protocol is installed.
 *
 * This function implements the RegisterProtocolNotify service.
 * See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @protocol		GUID of the protocol whose installation shall be
 *			notified
 * @event		event to be signaled upon installation of the protocol
 * @registration	key for retrieving the registration information
 * @return		status code
 */
static efi_status_t EFIAPI efi_register_protocol_notify(
						const efi_guid_t *protocol,
						struct efi_event *event,
						void **registration)
{
	EFI_ENTRY("%pUl, %p, %p", protocol, event, registration);
	return EFI_EXIT(EFI_OUT_OF_RESOURCES);
}

/*
 * Determine if an EFI handle implements a protocol.
 *
 * See the documentation of the LocateHandle service in the UEFI specification.
 *
 * @search_type		selection criterion
 * @protocol		GUID of the protocol
 * @search_key		registration key
 * @efiobj		handle
 * @return		0 if the handle implements the protocol
 */
static int efi_search(enum efi_locate_search_type search_type,
		      const efi_guid_t *protocol, void *search_key,
		      struct efi_object *efiobj)
{
	efi_status_t ret;

	switch (search_type) {
	case ALL_HANDLES:
		return 0;
	case BY_REGISTER_NOTIFY:
		/* TODO: RegisterProtocolNotify is not implemented yet */
		return -1;
	case BY_PROTOCOL:
		ret = efi_search_protocol(efiobj->handle, protocol, NULL);
		return (ret != EFI_SUCCESS);
	default:
		/* Invalid search type */
		return -1;
	}
}

/*
 * Locate handles implementing a protocol.
 *
 * This function is meant for U-Boot internal calls. For the API implementation
 * of the LocateHandle service see efi_locate_handle_ext.
 *
 * @search_type		selection criterion
 * @protocol		GUID of the protocol
 * @search_key		registration key
 * @buffer_size		size of the buffer to receive the handles in bytes
 * @buffer		buffer to receive the relevant handles
 * @return		status code
 */
static efi_status_t efi_locate_handle(
			enum efi_locate_search_type search_type,
			const efi_guid_t *protocol, void *search_key,
			efi_uintn_t *buffer_size, efi_handle_t *buffer)
{
	struct efi_object *efiobj;
	efi_uintn_t size = 0;

	/* Check parameters */
	switch (search_type) {
	case ALL_HANDLES:
		break;
	case BY_REGISTER_NOTIFY:
		if (!search_key)
			return EFI_INVALID_PARAMETER;
		/* RegisterProtocolNotify is not implemented yet */
		return EFI_UNSUPPORTED;
	case BY_PROTOCOL:
		if (!protocol)
			return EFI_INVALID_PARAMETER;
		break;
	default:
		return EFI_INVALID_PARAMETER;
	}

	/*
	 * efi_locate_handle_buffer uses this function for
	 * the calculation of the necessary buffer size.
	 * So do not require a buffer for buffersize == 0.
	 */
	if (!buffer_size || (*buffer_size && !buffer))
		return EFI_INVALID_PARAMETER;

	/* Count how much space we need */
	list_for_each_entry(efiobj, &efi_obj_list, link) {
		if (!efi_search(search_type, protocol, search_key, efiobj))
			size += sizeof(void *);
	}

	if (*buffer_size < size) {
		*buffer_size = size;
		return EFI_BUFFER_TOO_SMALL;
	}

	*buffer_size = size;
	if (size == 0)
		return EFI_NOT_FOUND;

	/* Then fill the array */
	list_for_each_entry(efiobj, &efi_obj_list, link) {
		if (!efi_search(search_type, protocol, search_key, efiobj))
			*buffer++ = efiobj->handle;
	}

	return EFI_SUCCESS;
}

/*
 * Locate handles implementing a protocol.
 *
 * This function implements the LocateHandle service.
 * See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @search_type		selection criterion
 * @protocol		GUID of the protocol
 * @search_key		registration key
 * @buffer_size		size of the buffer to receive the handles in bytes
 * @buffer		buffer to receive the relevant handles
 * @return		0 if the handle implements the protocol
 */
static efi_status_t EFIAPI efi_locate_handle_ext(
			enum efi_locate_search_type search_type,
			const efi_guid_t *protocol, void *search_key,
			efi_uintn_t *buffer_size, efi_handle_t *buffer)
{
	EFI_ENTRY("%d, %pUl, %p, %p, %p", search_type, protocol, search_key,
		  buffer_size, buffer);

	return EFI_EXIT(efi_locate_handle(search_type, protocol, search_key,
			buffer_size, buffer));
}

/* Collapses configuration table entries, removing index i */
static void efi_remove_configuration_table(int i)
{
	struct efi_configuration_table *this = &efi_conf_table[i];
	struct efi_configuration_table *next = &efi_conf_table[i + 1];
	struct efi_configuration_table *end = &efi_conf_table[systab.nr_tables];

	memmove(this, next, (ulong)end - (ulong)next);
	systab.nr_tables--;
}

/*
 * Adds, updates, or removes a configuration table.
 *
 * This function is used for internal calls. For the API implementation of the
 * InstallConfigurationTable service see efi_install_configuration_table_ext.
 *
 * @guid		GUID of the installed table
 * @table		table to be installed
 * @return		status code
 */
efi_status_t efi_install_configuration_table(const efi_guid_t *guid,
					     void *table)
{
	struct efi_event *evt;
	int i;

	if (!guid)
		return EFI_INVALID_PARAMETER;

	/* Check for guid override */
	for (i = 0; i < systab.nr_tables; i++) {
		if (!guidcmp(guid, &efi_conf_table[i].guid)) {
			if (table)
				efi_conf_table[i].table = table;
			else
				efi_remove_configuration_table(i);
			goto out;
		}
	}

	if (!table)
		return EFI_NOT_FOUND;

	/* No override, check for overflow */
	if (i >= ARRAY_SIZE(efi_conf_table))
		return EFI_OUT_OF_RESOURCES;

	/* Add a new entry */
	memcpy(&efi_conf_table[i].guid, guid, sizeof(*guid));
	efi_conf_table[i].table = table;
	systab.nr_tables = i + 1;

out:
	/* Notify that the configuration table was changed */
	list_for_each_entry(evt, &efi_events, link) {
		if (evt->group && !guidcmp(evt->group, guid)) {
			efi_signal_event(evt, false);
			break;
		}
	}

	return EFI_SUCCESS;
}

/*
 * Adds, updates, or removes a configuration table.
 *
 * This function implements the InstallConfigurationTable service.
 * See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @guid		GUID of the installed table
 * @table		table to be installed
 * @return		status code
 */
static efi_status_t EFIAPI efi_install_configuration_table_ext(efi_guid_t *guid,
							       void *table)
{
	EFI_ENTRY("%pUl, %p", guid, table);
	return EFI_EXIT(efi_install_configuration_table(guid, table));
}

/*
 * Initialize a loaded_image_info + loaded_image_info object with correct
 * protocols, boot-device, etc.
 *
 * @info		loaded image info to be passed to the entry point of the
 *			image
 * @obj			internal object associated with the loaded image
 * @device_path		device path of the loaded image
 * @file_path		file path of the loaded image
 * @return		status code
 */
efi_status_t efi_setup_loaded_image(
			struct efi_loaded_image *info, struct efi_object *obj,
			struct efi_device_path *device_path,
			struct efi_device_path *file_path)
{
	efi_status_t ret;

	/* Add internal object to object list */
	efi_add_handle(obj);
	/* efi_exit() assumes that the handle points to the info */
	obj->handle = info;

	info->file_path = file_path;

	if (device_path) {
		info->device_handle = efi_dp_find_obj(device_path, NULL);
		/*
		 * When asking for the device path interface, return
		 * bootefi_device_path
		 */
		ret = efi_add_protocol(obj->handle, &efi_guid_device_path,
				       device_path);
		if (ret != EFI_SUCCESS)
			goto failure;
	}

	/*
	 * When asking for the loaded_image interface, just
	 * return handle which points to loaded_image_info
	 */
	ret = efi_add_protocol(obj->handle, &efi_guid_loaded_image, info);
	if (ret != EFI_SUCCESS)
		goto failure;

	ret = efi_add_protocol(obj->handle,
			       &efi_guid_device_path_to_text_protocol,
			       (void *)&efi_device_path_to_text);
	if (ret != EFI_SUCCESS)
		goto failure;

	ret = efi_add_protocol(obj->handle,
			       &efi_guid_device_path_utilities_protocol,
			       (void *)&efi_device_path_utilities);
	if (ret != EFI_SUCCESS)
		goto failure;

	return ret;
failure:
	printf("ERROR: Failure to install protocols for loaded image\n");
	return ret;
}

/*
 * Load an image using a file path.
 *
 * @file_path		the path of the image to load
 * @buffer		buffer containing the loaded image
 * @return		status code
 */
efi_status_t efi_load_image_from_path(struct efi_device_path *file_path,
				      void **buffer)
{
	struct efi_file_info *info = NULL;
	struct efi_file_handle *f;
	static efi_status_t ret;
	uint64_t bs;

	f = efi_file_from_path(file_path);
	if (!f)
		return EFI_DEVICE_ERROR;

	bs = 0;
	EFI_CALL(ret = f->getinfo(f, (efi_guid_t *)&efi_file_info_guid,
				  &bs, info));
	if (ret == EFI_BUFFER_TOO_SMALL) {
		info = malloc(bs);
		EFI_CALL(ret = f->getinfo(f, (efi_guid_t *)&efi_file_info_guid,
					  &bs, info));
	}
	if (ret != EFI_SUCCESS)
		goto error;

	ret = efi_allocate_pool(EFI_LOADER_DATA, info->file_size, buffer);
	if (ret)
		goto error;

	EFI_CALL(ret = f->read(f, &info->file_size, *buffer));

error:
	free(info);
	EFI_CALL(f->close(f));

	if (ret != EFI_SUCCESS) {
		efi_free_pool(*buffer);
		*buffer = NULL;
	}

	return ret;
}

/*
 * Load an EFI image into memory.
 *
 * This function implements the LoadImage service.
 * See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @boot_policy		true for request originating from the boot manager
 * @parent_image	the caller's image handle
 * @file_path		the path of the image to load
 * @source_buffer	memory location from which the image is installed
 * @source_size		size of the memory area from which the image is
 *			installed
 * @image_handle	handle for the newly installed image
 * @return		status code
 */
static efi_status_t EFIAPI efi_load_image(bool boot_policy,
					  efi_handle_t parent_image,
					  struct efi_device_path *file_path,
					  void *source_buffer,
					  unsigned long source_size,
					  efi_handle_t *image_handle)
{
	struct efi_loaded_image *info;
	struct efi_object *obj;
	efi_status_t ret;

	EFI_ENTRY("%d, %p, %pD, %p, %ld, %p", boot_policy, parent_image,
		  file_path, source_buffer, source_size, image_handle);

	if (!image_handle || !parent_image) {
		ret = EFI_INVALID_PARAMETER;
		goto error;
	}

	if (!source_buffer && !file_path) {
		ret = EFI_NOT_FOUND;
		goto error;
	}

	info = calloc(1, sizeof(*info));
	if (!info) {
		ret = EFI_OUT_OF_RESOURCES;
		goto error;
	}
	obj = calloc(1, sizeof(*obj));
	if (!obj) {
		free(info);
		ret = EFI_OUT_OF_RESOURCES;
		goto error;
	}

	if (!source_buffer) {
		struct efi_device_path *dp, *fp;

		ret = efi_load_image_from_path(file_path, &source_buffer);
		if (ret != EFI_SUCCESS)
			goto failure;
		/*
		 * split file_path which contains both the device and
		 * file parts:
		 */
		efi_dp_split_file_path(file_path, &dp, &fp);
		ret = efi_setup_loaded_image(info, obj, dp, fp);
		if (ret != EFI_SUCCESS)
			goto failure;
	} else {
		/* In this case, file_path is the "device" path, ie.
		 * something like a HARDWARE_DEVICE:MEMORY_MAPPED
		 */
		ret = efi_setup_loaded_image(info, obj, file_path, NULL);
		if (ret != EFI_SUCCESS)
			goto failure;
	}
	info->reserved = efi_load_pe(source_buffer, info);
	if (!info->reserved) {
		ret = EFI_UNSUPPORTED;
		goto failure;
	}
	info->system_table = &systab;
	info->parent_handle = parent_image;
	*image_handle = obj->handle;
	return EFI_EXIT(EFI_SUCCESS);
failure:
	free(info);
	efi_delete_handle(obj);
error:
	return EFI_EXIT(ret);
}

/*
 * Call the entry point of an image.
 *
 * This function implements the StartImage service.
 * See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @image_handle	handle of the image
 * @exit_data_size	size of the buffer
 * @exit_data		buffer to receive the exit data of the called image
 * @return		status code
 */
static efi_status_t EFIAPI efi_start_image(efi_handle_t image_handle,
					   unsigned long *exit_data_size,
					   s16 **exit_data)
{
	EFIAPI efi_status_t (*entry)(efi_handle_t image_handle,
				     struct efi_system_table *st);
	struct efi_loaded_image *info = image_handle;
	efi_status_t ret;

	EFI_ENTRY("%p, %p, %p", image_handle, exit_data_size, exit_data);
	entry = info->reserved;

	efi_is_direct_boot = false;

	/* call the image! */
	if (setjmp(&info->exit_jmp)) {
		/*
		 * We called the entry point of the child image with EFI_CALL
		 * in the lines below. The child image called the Exit() boot
		 * service efi_exit() which executed the long jump that brought
		 * us to the current line. This implies that the second half
		 * of the EFI_CALL macro has not been executed.
		 */
#ifdef CONFIG_ARM
		/*
		 * efi_exit() called efi_restore_gd(). We have to undo this
		 * otherwise __efi_entry_check() will put the wrong value into
		 * app_gd.
		 */
		gd = app_gd;
#endif
		/*
		 * To get ready to call EFI_EXIT below we have to execute the
		 * missed out steps of EFI_CALL.
		 */
		assert(__efi_entry_check());
		debug("%sEFI: %lu returned by started image\n",
		      __efi_nesting_dec(),
		      (unsigned long)((uintptr_t)info->exit_status &
				      ~EFI_ERROR_MASK));
		return EFI_EXIT(info->exit_status);
	}

	ret = EFI_CALL(entry(image_handle, &systab));

	/*
	 * Usually UEFI applications call Exit() instead of returning.
	 * But because the world doesn not consist of ponies and unicorns,
	 * we're happy to emulate that behavior on behalf of a payload
	 * that forgot.
	 */
	return EFI_CALL(systab.boottime->exit(image_handle, ret, 0, NULL));
}

/*
 * Leave an EFI application or driver.
 *
 * This function implements the Exit service.
 * See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @image_handle	handle of the application or driver that is exiting
 * @exit_status		status code
 * @exit_data_size	size of the buffer in bytes
 * @exit_data		buffer with data describing an error
 * @return		status code
 */
static efi_status_t EFIAPI efi_exit(efi_handle_t image_handle,
				    efi_status_t exit_status,
				    unsigned long exit_data_size,
				    int16_t *exit_data)
{
	/*
	 * We require that the handle points to the original loaded
	 * image protocol interface.
	 *
	 * For getting the longjmp address this is safer than locating
	 * the protocol because the protocol may have been reinstalled
	 * pointing to another memory location.
	 *
	 * TODO: We should call the unload procedure of the loaded
	 *	 image protocol.
	 */
	struct efi_loaded_image *loaded_image_info = (void *)image_handle;

	EFI_ENTRY("%p, %ld, %ld, %p", image_handle, exit_status,
		  exit_data_size, exit_data);

	/* Make sure entry/exit counts for EFI world cross-overs match */
	EFI_EXIT(exit_status);

	/*
	 * But longjmp out with the U-Boot gd, not the application's, as
	 * the other end is a setjmp call inside EFI context.
	 */
	efi_restore_gd();

	loaded_image_info->exit_status = exit_status;
	longjmp(&loaded_image_info->exit_jmp, 1);

	panic("EFI application exited");
}

/*
 * Unload an EFI image.
 *
 * This function implements the UnloadImage service.
 * See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @image_handle	handle of the image to be unloaded
 * @return		status code
 */
static efi_status_t EFIAPI efi_unload_image(efi_handle_t image_handle)
{
	struct efi_object *efiobj;

	EFI_ENTRY("%p", image_handle);
	efiobj = efi_search_obj(image_handle);
	if (efiobj)
		list_del(&efiobj->link);

	return EFI_EXIT(EFI_SUCCESS);
}

/*
 * Fix up caches for EFI payloads if necessary.
 */
static void efi_exit_caches(void)
{
#if defined(CONFIG_ARM) && !defined(CONFIG_ARM64)
	/*
	 * Grub on 32bit ARM needs to have caches disabled before jumping into
	 * a zImage, but does not know of all cache layers. Give it a hand.
	 */
	if (efi_is_direct_boot)
		cleanup_before_linux();
#endif
}

/*
 * Stop all boot services.
 *
 * This function implements the ExitBootServices service.
 * See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * All timer events are disabled.
 * For exit boot services events the notification function is called.
 * The boot services are disabled in the system table.
 *
 * @image_handle	handle of the loaded image
 * @map_key		key of the memory map
 * @return		status code
 */
static efi_status_t EFIAPI efi_exit_boot_services(efi_handle_t image_handle,
						  unsigned long map_key)
{
	struct efi_event *evt;

	EFI_ENTRY("%p, %ld", image_handle, map_key);

	/* Make sure that notification functions are not called anymore */
	efi_tpl = TPL_HIGH_LEVEL;

	/* Check if ExitBootServices has already been called */
	if (!systab.boottime)
		return EFI_EXIT(EFI_SUCCESS);

	/* Add related events to the event group */
	list_for_each_entry(evt, &efi_events, link) {
		if (evt->type == EVT_SIGNAL_EXIT_BOOT_SERVICES)
			evt->group = &efi_guid_event_group_exit_boot_services;
	}
	/* Notify that ExitBootServices is invoked. */
	list_for_each_entry(evt, &efi_events, link) {
		if (evt->group &&
		    !guidcmp(evt->group,
			     &efi_guid_event_group_exit_boot_services)) {
			efi_signal_event(evt, false);
			break;
		}
	}

	/* TODO Should persist EFI variables here */

	board_quiesce_devices();

	/* Fix up caches for EFI payloads if necessary */
	efi_exit_caches();

	/* This stops all lingering devices */
	bootm_disable_interrupts();

	/* Disable boottime services */
	systab.con_in_handle = NULL;
	systab.con_in = NULL;
	systab.con_out_handle = NULL;
	systab.con_out = NULL;
	systab.stderr_handle = NULL;
	systab.std_err = NULL;
	systab.boottime = NULL;

	/* Recalculate CRC32 */
	systab.hdr.crc32 = 0;
	systab.hdr.crc32 = crc32(0, (const unsigned char *)&systab,
				 sizeof(struct efi_system_table));

	/* Give the payload some time to boot */
	efi_set_watchdog(0);
	WATCHDOG_RESET();

	return EFI_EXIT(EFI_SUCCESS);
}

/*
 * Get next value of the counter.
 *
 * This function implements the NextMonotonicCount service.
 * See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @count	returned value of the counter
 * @return	status code
 */
static efi_status_t EFIAPI efi_get_next_monotonic_count(uint64_t *count)
{
	static uint64_t mono;

	EFI_ENTRY("%p", count);
	*count = mono++;
	return EFI_EXIT(EFI_SUCCESS);
}

/*
 * Sleep.
 *
 * This function implements the Stall sercive.
 * See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @microseconds	period to sleep in microseconds
 * @return		status code
 */
static efi_status_t EFIAPI efi_stall(unsigned long microseconds)
{
	EFI_ENTRY("%ld", microseconds);
	udelay(microseconds);
	return EFI_EXIT(EFI_SUCCESS);
}

/*
 * Reset the watchdog timer.
 *
 * This function implements the SetWatchdogTimer service.
 * See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @timeout		seconds before reset by watchdog
 * @watchdog_code	code to be logged when resetting
 * @data_size		size of buffer in bytes
 * @watchdog_data	buffer with data describing the reset reason
 * @return		status code
 */
static efi_status_t EFIAPI efi_set_watchdog_timer(unsigned long timeout,
						  uint64_t watchdog_code,
						  unsigned long data_size,
						  uint16_t *watchdog_data)
{
	EFI_ENTRY("%ld, 0x%" PRIx64 ", %ld, %p", timeout, watchdog_code,
		  data_size, watchdog_data);
	return EFI_EXIT(efi_set_watchdog(timeout));
}

/*
 * Close a protocol.
 *
 * This function implements the CloseProtocol service.
 * See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @handle		handle on which the protocol shall be closed
 * @protocol		GUID of the protocol to close
 * @agent_handle	handle of the driver
 * @controller_handle	handle of the controller
 * @return		status code
 */
static efi_status_t EFIAPI efi_close_protocol(efi_handle_t handle,
					      const efi_guid_t *protocol,
					      efi_handle_t agent_handle,
					      efi_handle_t controller_handle)
{
	struct efi_handler *handler;
	struct efi_open_protocol_info_item *item;
	struct efi_open_protocol_info_item *pos;
	efi_status_t r;

	EFI_ENTRY("%p, %pUl, %p, %p", handle, protocol, agent_handle,
		  controller_handle);

	if (!agent_handle) {
		r = EFI_INVALID_PARAMETER;
		goto out;
	}
	r = efi_search_protocol(handle, protocol, &handler);
	if (r != EFI_SUCCESS)
		goto out;

	r = EFI_NOT_FOUND;
	list_for_each_entry_safe(item, pos, &handler->open_infos, link) {
		if (item->info.agent_handle == agent_handle &&
		    item->info.controller_handle == controller_handle) {
			efi_delete_open_info(item);
			r = EFI_SUCCESS;
			break;
		}
	}
out:
	return EFI_EXIT(r);
}

/*
 * Provide information about then open status of a protocol on a handle
 *
 * This function implements the OpenProtocolInformation service.
 * See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @handle		handle for which the information shall be retrieved
 * @protocol		GUID of the protocol
 * @entry_buffer	buffer to receive the open protocol information
 * @entry_count		number of entries available in the buffer
 * @return		status code
 */
static efi_status_t EFIAPI efi_open_protocol_information(
			efi_handle_t handle, const efi_guid_t *protocol,
			struct efi_open_protocol_info_entry **entry_buffer,
			efi_uintn_t *entry_count)
{
	unsigned long buffer_size;
	unsigned long count;
	struct efi_handler *handler;
	struct efi_open_protocol_info_item *item;
	efi_status_t r;

	EFI_ENTRY("%p, %pUl, %p, %p", handle, protocol, entry_buffer,
		  entry_count);

	/* Check parameters */
	if (!entry_buffer) {
		r = EFI_INVALID_PARAMETER;
		goto out;
	}