lib/efi_driver/efi_uclass.c - u-boot - Git at Google

 /*
  *  Uclass for EFI drivers
  *
  *  Copyright (c) 2017 Heinrich Schuchardt
  *
  *  SPDX-License-Identifier:     GPL-2.0+
  *
  * For each EFI driver the uclass
  * - creates a handle
  * - installs the driver binding protocol
  *
  * The uclass provides the bind, start, and stop entry points for the driver
  * binding protocol.
  *
  * In bind() and stop() it checks if the controller implements the protocol
  * supported by the EFI driver. In the start() function it calls the bind()
  * function of the EFI driver. In the stop() function it destroys the child
  * controllers.
  */

 #include <efi_driver.h>

 /*
  * Check node type. We do not support partitions as controller handles.
  *
  * @handle	handle to be checked
  * @return	status code
  */
 static efi_status_t check_node_type(efi_handle_t handle)
 {
 	efi_status_t r, ret = EFI_SUCCESS;
 	const struct efi_device_path *dp;

 	/* Open the device path protocol */
 	r = EFI_CALL(systab.boottime->open_protocol(
 			handle, &efi_guid_device_path, (void **)&dp,
 			NULL, NULL, EFI_OPEN_PROTOCOL_GET_PROTOCOL));
 	if (r == EFI_SUCCESS && dp) {
 		/* Get the last node */
 		const struct efi_device_path *node = efi_dp_last_node(dp);
 		/* We do not support partitions as controller */
 		if (!node || node->type == DEVICE_PATH_TYPE_MEDIA_DEVICE)
 			ret = EFI_UNSUPPORTED;
 	}
 	return ret;
 }

 /*
  * Check if the driver supports the controller.
  *
  * @this			driver binding protocol
  * @controller_handle		handle of the controller
  * @remaining_device_path	path specifying the child controller
  * @return			status code
  */
 static efi_status_t EFIAPI efi_uc_supported(
 		struct efi_driver_binding_protocol *this,
 		efi_handle_t controller_handle,
 		struct efi_device_path *remaining_device_path)
 {
 	efi_status_t r, ret;
 	void *interface;
 	struct efi_driver_binding_extended_protocol *bp =
 			(struct efi_driver_binding_extended_protocol *)this;

 	EFI_ENTRY("%p, %p, %ls", this, controller_handle,
 		  efi_dp_str(remaining_device_path));

 	ret = EFI_CALL(systab.boottime->open_protocol(
 			controller_handle, bp->ops->protocol,
 			&interface, this->driver_binding_handle,
 			controller_handle, EFI_OPEN_PROTOCOL_BY_DRIVER));
 	switch (ret) {
 	case EFI_ACCESS_DENIED:
 	case EFI_ALREADY_STARTED:
 		goto out;
 	case EFI_SUCCESS:
 		break;
 	default:
 		ret = EFI_UNSUPPORTED;
 		goto out;
 	}

 	ret = check_node_type(controller_handle);

 	r = EFI_CALL(systab.boottime->close_protocol(
 				controller_handle, bp->ops->protocol,
 				this->driver_binding_handle,
 				controller_handle));
 	if (r != EFI_SUCCESS)
 		ret = EFI_UNSUPPORTED;
 out:
 	return EFI_EXIT(ret);
 }

 /*
  * Create child controllers and attach driver.
  *
  * @this			driver binding protocol
  * @controller_handle		handle of the controller
  * @remaining_device_path	path specifying the child controller
  * @return			status code
  */
 static efi_status_t EFIAPI efi_uc_start(
 		struct efi_driver_binding_protocol *this,
 		efi_handle_t controller_handle,
 		struct efi_device_path *remaining_device_path)
 {
 	efi_status_t r, ret;
 	void *interface = NULL;
 	struct efi_driver_binding_extended_protocol *bp =
 			(struct efi_driver_binding_extended_protocol *)this;

 	EFI_ENTRY("%p, %pUl, %ls", this, controller_handle,
 		  efi_dp_str(remaining_device_path));

 	/* Attach driver to controller */
 	ret = EFI_CALL(systab.boottime->open_protocol(
 			controller_handle, bp->ops->protocol,
 			&interface, this->driver_binding_handle,
 			controller_handle, EFI_OPEN_PROTOCOL_BY_DRIVER));
 	switch (ret) {
 	case EFI_ACCESS_DENIED:
 	case EFI_ALREADY_STARTED:
 		goto out;
 	case EFI_SUCCESS:
 		break;
 	default:
 		ret =  EFI_UNSUPPORTED;
 		goto out;
 	}
 	ret = check_node_type(controller_handle);
 	if (ret != EFI_SUCCESS) {
 		r = EFI_CALL(systab.boottime->close_protocol(
 				controller_handle, bp->ops->protocol,
 				this->driver_binding_handle,
 				controller_handle));
 		if (r != EFI_SUCCESS)
 			EFI_PRINT("Failure to close handle\n");
 		goto out;
 	}

 	/* TODO: driver specific stuff */
 	bp->ops->bind(controller_handle, interface);

 out:
 	return EFI_EXIT(ret);
 }

 /*
  * Remove a single child controller from the parent controller.
  *
  * @controller_handle	parent controller
  * @child_handle	child controller
  * @return		status code
  */
 static efi_status_t disconnect_child(efi_handle_t controller_handle,
 				     efi_handle_t child_handle)
 {
 	efi_status_t ret;
 	efi_guid_t *guid_controller = NULL;
 	efi_guid_t *guid_child_controller = NULL;

 	ret = EFI_CALL(systab.boottime->close_protocol(
 				controller_handle, guid_controller,
 				child_handle, child_handle));
 	if (ret != EFI_SUCCESS) {
 		EFI_PRINT("Cannot close protocol\n");
 		return ret;
 	}
 	ret = EFI_CALL(systab.boottime->uninstall_protocol_interface(
 				child_handle, guid_child_controller, NULL));
 	if (ret != EFI_SUCCESS) {
 		EFI_PRINT("Cannot uninstall protocol interface\n");
 		return ret;
 	}
 	return ret;
 }

 /*
  * Remove child controllers and disconnect the controller.
  *
  * @this			driver binding protocol
  * @controller_handle		handle of the controller
  * @number_of_children		number of child controllers to remove
  * @child_handle_buffer		handles of the child controllers to remove
  * @return			status code
  */
 static efi_status_t EFIAPI efi_uc_stop(
 		struct efi_driver_binding_protocol *this,
 		efi_handle_t controller_handle,
 		size_t number_of_children,
 		efi_handle_t *child_handle_buffer)
 {
 	efi_status_t ret;
 	efi_uintn_t count;
 	struct efi_open_protocol_info_entry *entry_buffer;
 	efi_guid_t *guid_controller = NULL;

 	EFI_ENTRY("%p, %pUl, %zu, %p", this, controller_handle,
 		  number_of_children, child_handle_buffer);

 	/* Destroy provided child controllers */
 	if (number_of_children) {
 		efi_uintn_t i;

 		for (i = 0; i < number_of_children; ++i) {
 			ret = disconnect_child(controller_handle,
 					       child_handle_buffer[i]);
 			if (ret != EFI_SUCCESS)
 				return ret;
 		}
 		return EFI_SUCCESS;
 	}

 	/* Destroy all children */
 	ret = EFI_CALL(systab.boottime->open_protocol_information(
 					controller_handle, guid_controller,
 					&entry_buffer, &count));
 	if (ret != EFI_SUCCESS)
 		goto out;
 	while (count) {
 		if (entry_buffer[--count].attributes &
 		    EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER) {
 			ret = disconnect_child(
 					controller_handle,
 					entry_buffer[count].agent_handle);
 			if (ret != EFI_SUCCESS)
 				goto out;
 		}
 	}
 	ret = EFI_CALL(systab.boottime->free_pool(entry_buffer));
 	if (ret != EFI_SUCCESS)
 		printf("%s(%u) %s: ERROR: Cannot free pool\n",
 		       __FILE__, __LINE__, __func__);

 	/* Detach driver from controller */
 	ret = EFI_CALL(systab.boottime->close_protocol(
 			controller_handle, guid_controller,
 			this->driver_binding_handle, controller_handle));
 out:
 	return EFI_EXIT(ret);
 }

 static efi_status_t efi_add_driver(struct driver *drv)
 {
 	efi_status_t ret;
 	const struct efi_driver_ops *ops = drv->ops;
 	struct efi_driver_binding_extended_protocol *bp;

 	debug("EFI: Adding driver '%s'\n", drv->name);
 	if (!ops->protocol) {
 		printf("EFI: ERROR: protocol GUID missing for driver '%s'\n",
 		       drv->name);
 		return EFI_INVALID_PARAMETER;
 	}
 	bp = calloc(1, sizeof(struct efi_driver_binding_extended_protocol));
 	if (!bp)
 		return EFI_OUT_OF_RESOURCES;

 	bp->bp.supported = efi_uc_supported;
 	bp->bp.start = efi_uc_start;
 	bp->bp.stop = efi_uc_stop;
 	bp->bp.version = 0xffffffff;
 	bp->ops = drv->ops;

 	ret = efi_create_handle(&bp->bp.driver_binding_handle);
 	if (ret != EFI_SUCCESS) {
 		free(bp);
 		goto out;
 	}
 	bp->bp.image_handle = bp->bp.driver_binding_handle;
 	ret = efi_add_protocol(bp->bp.driver_binding_handle,
 			       &efi_guid_driver_binding_protocol, bp);
 	if (ret != EFI_SUCCESS) {
 		efi_delete_handle(bp->bp.driver_binding_handle);
 		free(bp);
 		goto out;
 	}
 out:
 	return ret;
 }

 /*
  * Initialize the EFI drivers.
  * Called by board_init_r().
  *
  * @return	0 = success, any other value will stop further execution
  */
 efi_status_t efi_driver_init(void)
 {
 	struct driver *drv;
 	efi_status_t ret = EFI_SUCCESS;

 	/* Save 'gd' pointer */
 	efi_save_gd();

 	debug("EFI: Initializing EFI driver framework\n");
 	for (drv = ll_entry_start(struct driver, driver);
 	     drv < ll_entry_end(struct driver, driver); ++drv) {
 		if (drv->id == UCLASS_EFI) {
 			ret = efi_add_driver(drv);
 			if (ret != EFI_SUCCESS) {
 				printf("EFI: ERROR: failed to add driver %s\n",
 				       drv->name);
 				break;
 			}
 		}
 	}
 	return ret;
 }

 static int efi_uc_init(struct uclass *class)
 {
 	printf("EFI: Initializing UCLASS_EFI\n");
 	return 0;
 }

 static int efi_uc_destroy(struct uclass *class)
 {
 	printf("Destroying  UCLASS_EFI\n");
 	return 0;
 }

 UCLASS_DRIVER(efi) = {
 	.name		= "efi",
 	.id		= UCLASS_EFI,
 	.init		= efi_uc_init,
 	.destroy	= efi_uc_destroy,
 };
	/*
	* Uclass for EFI drivers
	*
	* Copyright (c) 2017 Heinrich Schuchardt
	*
	* SPDX-License-Identifier: GPL-2.0+
	*
	* For each EFI driver the uclass
	* - creates a handle
	* - installs the driver binding protocol
	*
	* The uclass provides the bind, start, and stop entry points for the driver
	* binding protocol.
	*
	* In bind() and stop() it checks if the controller implements the protocol
	* supported by the EFI driver. In the start() function it calls the bind()
	* function of the EFI driver. In the stop() function it destroys the child
	* controllers.
	*/

	#include <efi_driver.h>

	/*
	* Check node type. We do not support partitions as controller handles.
	*
	* @handle handle to be checked
	* @return status code
	*/
	static efi_status_t check_node_type(efi_handle_t handle)
	{
	efi_status_t r, ret = EFI_SUCCESS;
	const struct efi_device_path *dp;

	/* Open the device path protocol */
	r = EFI_CALL(systab.boottime->open_protocol(
	handle, &efi_guid_device_path, (void **)&dp,
	NULL, NULL, EFI_OPEN_PROTOCOL_GET_PROTOCOL));
	if (r == EFI_SUCCESS && dp) {
	/* Get the last node */
	const struct efi_device_path *node = efi_dp_last_node(dp);
	/* We do not support partitions as controller */
	if (!node \|\| node->type == DEVICE_PATH_TYPE_MEDIA_DEVICE)
	ret = EFI_UNSUPPORTED;
	}
	return ret;
	}

	/*
	* Check if the driver supports the controller.
	*
	* @this driver binding protocol
	* @controller_handle handle of the controller
	* @remaining_device_path path specifying the child controller
	* @return status code
	*/
	static efi_status_t EFIAPI efi_uc_supported(
	struct efi_driver_binding_protocol *this,
	efi_handle_t controller_handle,
	struct efi_device_path *remaining_device_path)
	{
	efi_status_t r, ret;
	void *interface;
	struct efi_driver_binding_extended_protocol *bp =
	(struct efi_driver_binding_extended_protocol *)this;

	EFI_ENTRY("%p, %p, %ls", this, controller_handle,
	efi_dp_str(remaining_device_path));

	ret = EFI_CALL(systab.boottime->open_protocol(
	controller_handle, bp->ops->protocol,
	&interface, this->driver_binding_handle,
	controller_handle, EFI_OPEN_PROTOCOL_BY_DRIVER));
	switch (ret) {
	case EFI_ACCESS_DENIED:
	case EFI_ALREADY_STARTED:
	goto out;
	case EFI_SUCCESS:
	break;
	default:
	ret = EFI_UNSUPPORTED;
	goto out;
	}

	ret = check_node_type(controller_handle);

	r = EFI_CALL(systab.boottime->close_protocol(
	controller_handle, bp->ops->protocol,
	this->driver_binding_handle,
	controller_handle));
	if (r != EFI_SUCCESS)
	ret = EFI_UNSUPPORTED;
	out:
	return EFI_EXIT(ret);
	}

	/*
	* Create child controllers and attach driver.
	*
	* @this driver binding protocol
	* @controller_handle handle of the controller
	* @remaining_device_path path specifying the child controller
	* @return status code
	*/
	static efi_status_t EFIAPI efi_uc_start(
	struct efi_driver_binding_protocol *this,
	efi_handle_t controller_handle,
	struct efi_device_path *remaining_device_path)
	{
	efi_status_t r, ret;
	void *interface = NULL;
	struct efi_driver_binding_extended_protocol *bp =
	(struct efi_driver_binding_extended_protocol *)this;

	EFI_ENTRY("%p, %pUl, %ls", this, controller_handle,
	efi_dp_str(remaining_device_path));

	/* Attach driver to controller */
	ret = EFI_CALL(systab.boottime->open_protocol(
	controller_handle, bp->ops->protocol,
	&interface, this->driver_binding_handle,
	controller_handle, EFI_OPEN_PROTOCOL_BY_DRIVER));
	switch (ret) {
	case EFI_ACCESS_DENIED:
	case EFI_ALREADY_STARTED:
	goto out;
	case EFI_SUCCESS:
	break;
	default:
	ret = EFI_UNSUPPORTED;
	goto out;
	}
	ret = check_node_type(controller_handle);
	if (ret != EFI_SUCCESS) {
	r = EFI_CALL(systab.boottime->close_protocol(
	controller_handle, bp->ops->protocol,
	this->driver_binding_handle,
	controller_handle));
	if (r != EFI_SUCCESS)
	EFI_PRINT("Failure to close handle\n");
	goto out;
	}

	/* TODO: driver specific stuff */
	bp->ops->bind(controller_handle, interface);

	out:
	return EFI_EXIT(ret);
	}

	/*
	* Remove a single child controller from the parent controller.
	*
	* @controller_handle parent controller
	* @child_handle child controller
	* @return status code
	*/
	static efi_status_t disconnect_child(efi_handle_t controller_handle,
	efi_handle_t child_handle)
	{
	efi_status_t ret;
	efi_guid_t *guid_controller = NULL;
	efi_guid_t *guid_child_controller = NULL;

	ret = EFI_CALL(systab.boottime->close_protocol(
	controller_handle, guid_controller,
	child_handle, child_handle));
	if (ret != EFI_SUCCESS) {
	EFI_PRINT("Cannot close protocol\n");
	return ret;
	}
	ret = EFI_CALL(systab.boottime->uninstall_protocol_interface(
	child_handle, guid_child_controller, NULL));
	if (ret != EFI_SUCCESS) {
	EFI_PRINT("Cannot uninstall protocol interface\n");
	return ret;
	}
	return ret;
	}

	/*
	* Remove child controllers and disconnect the controller.
	*
	* @this driver binding protocol
	* @controller_handle handle of the controller
	* @number_of_children number of child controllers to remove
	* @child_handle_buffer handles of the child controllers to remove
	* @return status code
	*/
	static efi_status_t EFIAPI efi_uc_stop(
	struct efi_driver_binding_protocol *this,
	efi_handle_t controller_handle,
	size_t number_of_children,
	efi_handle_t *child_handle_buffer)
	{
	efi_status_t ret;
	efi_uintn_t count;
	struct efi_open_protocol_info_entry *entry_buffer;
	efi_guid_t *guid_controller = NULL;

	EFI_ENTRY("%p, %pUl, %zu, %p", this, controller_handle,
	number_of_children, child_handle_buffer);

	/* Destroy provided child controllers */
	if (number_of_children) {
	efi_uintn_t i;

	for (i = 0; i < number_of_children; ++i) {
	ret = disconnect_child(controller_handle,
	child_handle_buffer[i]);
	if (ret != EFI_SUCCESS)
	return ret;
	}
	return EFI_SUCCESS;
	}

	/* Destroy all children */
	ret = EFI_CALL(systab.boottime->open_protocol_information(
	controller_handle, guid_controller,
	&entry_buffer, &count));
	if (ret != EFI_SUCCESS)
	goto out;
	while (count) {
	if (entry_buffer[--count].attributes &
	EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER) {
	ret = disconnect_child(
	controller_handle,
	entry_buffer[count].agent_handle);
	if (ret != EFI_SUCCESS)
	goto out;
	}
	}
	ret = EFI_CALL(systab.boottime->free_pool(entry_buffer));
	if (ret != EFI_SUCCESS)
	printf("%s(%u) %s: ERROR: Cannot free pool\n",
	__FILE__, __LINE__, __func__);

	/* Detach driver from controller */
	ret = EFI_CALL(systab.boottime->close_protocol(
	controller_handle, guid_controller,
	this->driver_binding_handle, controller_handle));
	out:
	return EFI_EXIT(ret);
	}

	static efi_status_t efi_add_driver(struct driver *drv)
	{
	efi_status_t ret;
	const struct efi_driver_ops *ops = drv->ops;
	struct efi_driver_binding_extended_protocol *bp;

	debug("EFI: Adding driver '%s'\n", drv->name);
	if (!ops->protocol) {
	printf("EFI: ERROR: protocol GUID missing for driver '%s'\n",
	drv->name);
	return EFI_INVALID_PARAMETER;
	}
	bp = calloc(1, sizeof(struct efi_driver_binding_extended_protocol));
	if (!bp)
	return EFI_OUT_OF_RESOURCES;

	bp->bp.supported = efi_uc_supported;
	bp->bp.start = efi_uc_start;
	bp->bp.stop = efi_uc_stop;
	bp->bp.version = 0xffffffff;
	bp->ops = drv->ops;

	ret = efi_create_handle(&bp->bp.driver_binding_handle);
	if (ret != EFI_SUCCESS) {
	free(bp);
	goto out;
	}
	bp->bp.image_handle = bp->bp.driver_binding_handle;
	ret = efi_add_protocol(bp->bp.driver_binding_handle,
	&efi_guid_driver_binding_protocol, bp);
	if (ret != EFI_SUCCESS) {
	efi_delete_handle(bp->bp.driver_binding_handle);
	free(bp);
	goto out;
	}
	out:
	return ret;
	}

	/*
	* Initialize the EFI drivers.
	* Called by board_init_r().
	*
	* @return 0 = success, any other value will stop further execution
	*/
	efi_status_t efi_driver_init(void)
	{
	struct driver *drv;
	efi_status_t ret = EFI_SUCCESS;

	/* Save 'gd' pointer */
	efi_save_gd();

	debug("EFI: Initializing EFI driver framework\n");
	for (drv = ll_entry_start(struct driver, driver);
	drv < ll_entry_end(struct driver, driver); ++drv) {
	if (drv->id == UCLASS_EFI) {
	ret = efi_add_driver(drv);
	if (ret != EFI_SUCCESS) {
	printf("EFI: ERROR: failed to add driver %s\n",
	drv->name);
	break;
	}
	}
	}
	return ret;
	}

	static int efi_uc_init(struct uclass *class)
	{
	printf("EFI: Initializing UCLASS_EFI\n");
	return 0;
	}

	static int efi_uc_destroy(struct uclass *class)
	{
	printf("Destroying UCLASS_EFI\n");
	return 0;
	}

	UCLASS_DRIVER(efi) = {
	.name = "efi",
	.id = UCLASS_EFI,
	.init = efi_uc_init,
	.destroy = efi_uc_destroy,
	};