From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752307AbeBUIT4 (ORCPT ); Wed, 21 Feb 2018 03:19:56 -0500 Received: from mx2.suse.de ([195.135.220.15]:48565 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752230AbeBUITz (ORCPT ); Wed, 21 Feb 2018 03:19:55 -0500 Subject: Re: [PATCH 1/9] drm/xen-front: Introduce Xen para-virtualized frontend driver To: Oleksandr Andrushchenko , xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, airlied@linux.ie, daniel.vetter@intel.com, seanpaul@chromium.org, gustavo@padovan.org, boris.ostrovsky@oracle.com, konrad.wilk@oracle.com Cc: Oleksandr Andrushchenko References: <1519200222-20623-1-git-send-email-andr2000@gmail.com> <1519200222-20623-2-git-send-email-andr2000@gmail.com> From: Juergen Gross Message-ID: Date: Wed, 21 Feb 2018 09:19:50 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <1519200222-20623-2-git-send-email-andr2000@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 21/02/18 09:03, Oleksandr Andrushchenko wrote: > From: Oleksandr Andrushchenko > > Introduce skeleton of the para-virtualized Xen display > frontend driver. This patch only adds required > essential stubs. > > Signed-off-by: Oleksandr Andrushchenko > --- > 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. Use SPDX identifier instead (same applies for all other new sources): // SPDX-License-Identifier: GPL-2.0 > + * > + * Copyright (C) 2016-2018 EPAM Systems Inc. > + * > + * Author: Oleksandr Andrushchenko > + */ > + > +#include > + > +#include > +#include > +#include > + > +#include > + > +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; > + } Why not? Wouldn't that be possible in case of the backend living in a driver domain? Juergen