1 files changed, 330 insertions, 0 deletions
diff --git a/lib/efi_driver/efi_uclass.c b/lib/efi_driver/efi_uclass.c
new file mode 100644
index 0000000000..90797f96d8
--- /dev/null
+++ b/lib/efi_driver/efi_uclass.c
@@ -0,0 +1,330 @@
+/*
+ *  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
+ */
+int efi_driver_init(void)
+{
+	struct driver *drv;
+	int ret = 0;
+
+	/* 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) {
+				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,
+};