From: Oleksandr Andrushchenko oleksandr_andrushchenko@epam.com
Introduce skeleton of the para-virtualized Xen display frontend driver. This patch only adds required essential stubs.
Signed-off-by: Oleksandr Andrushchenko oleksandr_andrushchenko@epam.com --- drivers/gpu/drm/Kconfig | 2 + drivers/gpu/drm/Makefile | 1 + drivers/gpu/drm/xen/Kconfig | 17 ++++++++ drivers/gpu/drm/xen/Makefile | 5 +++ drivers/gpu/drm/xen/xen_drm_front.c | 83 +++++++++++++++++++++++++++++++++++++ 5 files changed, 108 insertions(+) create mode 100644 drivers/gpu/drm/xen/Kconfig create mode 100644 drivers/gpu/drm/xen/Makefile create mode 100644 drivers/gpu/drm/xen/xen_drm_front.c
diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig index deeefa7a1773..757825ac60df 100644 --- a/drivers/gpu/drm/Kconfig +++ b/drivers/gpu/drm/Kconfig @@ -289,6 +289,8 @@ source "drivers/gpu/drm/pl111/Kconfig"
source "drivers/gpu/drm/tve200/Kconfig"
+source "drivers/gpu/drm/xen/Kconfig" + # Keep legacy drivers last
menuconfig DRM_LEGACY diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile index 50093ff4479b..9d66657ea117 100644 --- a/drivers/gpu/drm/Makefile +++ b/drivers/gpu/drm/Makefile @@ -103,3 +103,4 @@ obj-$(CONFIG_DRM_MXSFB) += mxsfb/ obj-$(CONFIG_DRM_TINYDRM) += tinydrm/ obj-$(CONFIG_DRM_PL111) += pl111/ obj-$(CONFIG_DRM_TVE200) += tve200/ +obj-$(CONFIG_DRM_XEN) += xen/ diff --git a/drivers/gpu/drm/xen/Kconfig b/drivers/gpu/drm/xen/Kconfig new file mode 100644 index 000000000000..4cca160782ab --- /dev/null +++ b/drivers/gpu/drm/xen/Kconfig @@ -0,0 +1,17 @@ +config DRM_XEN + bool "DRM Support for Xen guest OS" + depends on XEN + help + Choose this option if you want to enable DRM support + for Xen. + +config DRM_XEN_FRONTEND + tristate "Para-virtualized frontend driver for Xen guest OS" + depends on DRM_XEN + depends on DRM + select DRM_KMS_HELPER + select VIDEOMODE_HELPERS + select XEN_XENBUS_FRONTEND + help + Choose this option if you want to enable a para-virtualized + frontend DRM/KMS driver for Xen guest OSes. diff --git a/drivers/gpu/drm/xen/Makefile b/drivers/gpu/drm/xen/Makefile new file mode 100644 index 000000000000..967074d348f6 --- /dev/null +++ b/drivers/gpu/drm/xen/Makefile @@ -0,0 +1,5 @@ +# SPDX-License-Identifier: GPL-2.0 + +drm_xen_front-objs := xen_drm_front.o + +obj-$(CONFIG_DRM_XEN_FRONTEND) += drm_xen_front.o diff --git a/drivers/gpu/drm/xen/xen_drm_front.c b/drivers/gpu/drm/xen/xen_drm_front.c new file mode 100644 index 000000000000..fd372fb464a1 --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front.c @@ -0,0 +1,83 @@ +/* + * Xen para-virtual DRM device + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko oleksandr_andrushchenko@epam.com + */ + +#include <drm/drmP.h> + +#include <xen/platform_pci.h> +#include <xen/xen.h> +#include <xen/xenbus.h> + +#include <xen/interface/io/displif.h> + +static void backend_on_changed(struct xenbus_device *xb_dev, + enum xenbus_state backend_state) +{ +} + +static int xen_drv_probe(struct xenbus_device *xb_dev, + const struct xenbus_device_id *id) +{ + return 0; +} + +static int xen_drv_remove(struct xenbus_device *dev) +{ + return 0; +} + +static const struct xenbus_device_id xen_drv_ids[] = { + { XENDISPL_DRIVER_NAME }, + { "" } +}; + +static struct xenbus_driver xen_driver = { + .ids = xen_drv_ids, + .probe = xen_drv_probe, + .remove = xen_drv_remove, + .otherend_changed = backend_on_changed, +}; + +static int __init xen_drv_init(void) +{ + if (!xen_domain()) + return -ENODEV; + + if (xen_initial_domain()) { + DRM_ERROR(XENDISPL_DRIVER_NAME " cannot run in initial domain\n"); + return -ENODEV; + } + + if (!xen_has_pv_devices()) + return -ENODEV; + + DRM_INFO("Registering XEN PV " XENDISPL_DRIVER_NAME "\n"); + return xenbus_register_frontend(&xen_driver); +} + +static void __exit xen_drv_cleanup(void) +{ + DRM_INFO("Unregistering XEN PV " XENDISPL_DRIVER_NAME "\n"); + xenbus_unregister_driver(&xen_driver); +} + +module_init(xen_drv_init); +module_exit(xen_drv_cleanup); + +MODULE_DESCRIPTION("Xen para-virtualized display device frontend"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("xen:"XENDISPL_DRIVER_NAME);