From: Oleksandr Andrushchenko oleksandr_andrushchenko@epam.com
Read configuration values from Xen store according to xen/interface/io/displif.h protocol: - read connector(s) configuration - read buffer allocation mode (backend/frontend)
Signed-off-by: Oleksandr Andrushchenko oleksandr_andrushchenko@epam.com --- drivers/gpu/drm/xen/Makefile | 3 +- drivers/gpu/drm/xen/xen_drm_front.c | 9 ++++ drivers/gpu/drm/xen/xen_drm_front.h | 3 ++ drivers/gpu/drm/xen/xen_drm_front_cfg.c | 77 +++++++++++++++++++++++++++++++++ drivers/gpu/drm/xen/xen_drm_front_cfg.h | 37 ++++++++++++++++ 5 files changed, 128 insertions(+), 1 deletion(-) create mode 100644 drivers/gpu/drm/xen/xen_drm_front_cfg.c create mode 100644 drivers/gpu/drm/xen/xen_drm_front_cfg.h
diff --git a/drivers/gpu/drm/xen/Makefile b/drivers/gpu/drm/xen/Makefile index 3283e104c7bb..d3ec8c8589e0 100644 --- a/drivers/gpu/drm/xen/Makefile +++ b/drivers/gpu/drm/xen/Makefile @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 OR MIT
-drm_xen_front-objs := xen_drm_front.o +drm_xen_front-objs := xen_drm_front.o \ + xen_drm_front_cfg.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 index 520b5b34520b..ca42ceb24a40 100644 --- a/drivers/gpu/drm/xen/xen_drm_front.c +++ b/drivers/gpu/drm/xen/xen_drm_front.c @@ -24,6 +24,15 @@ static void xen_drv_remove_internal(struct xen_drm_front_info *front_info)
static int displback_initwait(struct xen_drm_front_info *front_info) { + struct xen_drm_front_cfg *cfg = &front_info->cfg; + int ret; + + cfg->front_info = front_info; + ret = xen_drm_front_cfg_card(front_info, cfg); + if (ret < 0) + return ret; + + DRM_INFO("Have %d conector(s)\n", cfg->num_connectors); return 0; }
diff --git a/drivers/gpu/drm/xen/xen_drm_front.h b/drivers/gpu/drm/xen/xen_drm_front.h index 8b8d4d1e0816..034a3987657e 100644 --- a/drivers/gpu/drm/xen/xen_drm_front.h +++ b/drivers/gpu/drm/xen/xen_drm_front.h @@ -11,8 +11,11 @@ #ifndef __XEN_DRM_FRONT_H_ #define __XEN_DRM_FRONT_H_
+#include "xen_drm_front_cfg.h" + struct xen_drm_front_info { struct xenbus_device *xb_dev; + struct xen_drm_front_cfg cfg; };
#endif /* __XEN_DRM_FRONT_H_ */ diff --git a/drivers/gpu/drm/xen/xen_drm_front_cfg.c b/drivers/gpu/drm/xen/xen_drm_front_cfg.c new file mode 100644 index 000000000000..9a0b2b8e6169 --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front_cfg.c @@ -0,0 +1,77 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko oleksandr_andrushchenko@epam.com + */ + +#include <drm/drmP.h> + +#include <linux/device.h> + +#include <xen/interface/io/displif.h> +#include <xen/xenbus.h> + +#include "xen_drm_front.h" +#include "xen_drm_front_cfg.h" + +static int cfg_connector(struct xen_drm_front_info *front_info, + struct xen_drm_front_cfg_connector *connector, + const char *path, int index) +{ + char *connector_path; + + connector_path = devm_kasprintf(&front_info->xb_dev->dev, + GFP_KERNEL, "%s/%d", path, index); + if (!connector_path) + return -ENOMEM; + + if (xenbus_scanf(XBT_NIL, connector_path, XENDISPL_FIELD_RESOLUTION, + "%d" XENDISPL_RESOLUTION_SEPARATOR "%d", + &connector->width, &connector->height) < 0) { + /* either no entry configured or wrong resolution set */ + connector->width = 0; + connector->height = 0; + return -EINVAL; + } + + connector->xenstore_path = connector_path; + + DRM_INFO("Connector %s: resolution %dx%d\n", + connector_path, connector->width, connector->height); + return 0; +} + +int xen_drm_front_cfg_card(struct xen_drm_front_info *front_info, + struct xen_drm_front_cfg *cfg) +{ + struct xenbus_device *xb_dev = front_info->xb_dev; + int ret, i; + + if (xenbus_read_unsigned(front_info->xb_dev->nodename, + XENDISPL_FIELD_BE_ALLOC, 0)) { + DRM_INFO("Backend can provide display buffers\n"); + cfg->be_alloc = true; + } + + cfg->num_connectors = 0; + for (i = 0; i < ARRAY_SIZE(cfg->connectors); i++) { + ret = cfg_connector(front_info, + &cfg->connectors[i], xb_dev->nodename, i); + if (ret < 0) + break; + cfg->num_connectors++; + } + + if (!cfg->num_connectors) { + DRM_ERROR("No connector(s) configured at %s\n", + xb_dev->nodename); + return -ENODEV; + } + + return 0; +} + diff --git a/drivers/gpu/drm/xen/xen_drm_front_cfg.h b/drivers/gpu/drm/xen/xen_drm_front_cfg.h new file mode 100644 index 000000000000..6e7af670f8cd --- /dev/null +++ b/drivers/gpu/drm/xen/xen_drm_front_cfg.h @@ -0,0 +1,37 @@ +/* SPDX-License-Identifier: GPL-2.0 OR MIT */ + +/* + * Xen para-virtual DRM device + * + * Copyright (C) 2016-2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko oleksandr_andrushchenko@epam.com + */ + +#ifndef __XEN_DRM_FRONT_CFG_H_ +#define __XEN_DRM_FRONT_CFG_H_ + +#include <linux/types.h> + +#define XEN_DRM_FRONT_MAX_CRTCS 4 + +struct xen_drm_front_cfg_connector { + int width; + int height; + char *xenstore_path; +}; + +struct xen_drm_front_cfg { + struct xen_drm_front_info *front_info; + /* number of connectors in this configuration */ + int num_connectors; + /* connector configurations */ + struct xen_drm_front_cfg_connector connectors[XEN_DRM_FRONT_MAX_CRTCS]; + /* set if dumb buffers are allocated externally on backend side */ + bool be_alloc; +}; + +int xen_drm_front_cfg_card(struct xen_drm_front_info *front_info, + struct xen_drm_front_cfg *cfg); + +#endif /* __XEN_DRM_FRONT_CFG_H_ */