Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 156 insertions, 0 deletions

diff --git a/drivers/gpu/drm/xen/xen_drm_front.h b/drivers/gpu/drm/xen/xen_drm_front.h
new file mode 100644
index 000000000..a987c78ab
--- /dev/null
+++ b/drivers/gpu/drm/xen/xen_drm_front.h
@@ -0,0 +1,156 @@
+/* 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_H_
+#define __XEN_DRM_FRONT_H_
+
+#include <linux/scatterlist.h>
+
+#include <drm/drm_connector.h>
+#include <drm/drm_simple_kms_helper.h>
+
+#include "xen_drm_front_cfg.h"
+
+struct drm_device;
+struct drm_framebuffer;
+struct drm_gem_object;
+struct drm_pending_vblank_event;
+
+/**
+ * DOC: Driver modes of operation in terms of display buffers used
+ *
+ * Depending on the requirements for the para-virtualized environment, namely
+ * requirements dictated by the accompanying DRM/(v)GPU drivers running in both
+ * host and guest environments, display buffers can be allocated by either
+ * frontend driver or backend.
+ */
+
+/**
+ * DOC: Buffers allocated by the frontend driver
+ *
+ * In this mode of operation driver allocates buffers from system memory.
+ *
+ * Note! If used with accompanying DRM/(v)GPU drivers this mode of operation
+ * may require IOMMU support on the platform, so accompanying DRM/vGPU
+ * hardware can still reach display buffer memory while importing PRIME
+ * buffers from the frontend driver.
+ */
+
+/**
+ * DOC: Buffers allocated by the backend
+ *
+ * This mode of operation is run-time configured via guest domain configuration
+ * through XenStore entries.
+ *
+ * For systems which do not provide IOMMU support, but having specific
+ * requirements for display buffers it is possible to allocate such buffers
+ * at backend side and share those with the frontend.
+ * For example, if host domain is 1:1 mapped and has DRM/GPU hardware expecting
+ * physically contiguous memory, this allows implementing zero-copying
+ * use-cases.
+ *
+ * Note, while using this scenario the following should be considered:
+ *
+ * #. If guest domain dies then pages/grants received from the backend
+ *    cannot be claimed back
+ *
+ * #. Misbehaving guest may send too many requests to the
+ *    backend exhausting its grant references and memory
+ *    (consider this from security POV)
+ */
+
+/**
+ * DOC: Driver limitations
+ *
+ * #. Only primary plane without additional properties is supported.
+ *
+ * #. Only one video mode per connector supported which is configured
+ *    via XenStore.
+ *
+ * #. All CRTCs operate at fixed frequency of 60Hz.
+ */
+
+/* timeout in ms to wait for backend to respond */
+#define XEN_DRM_FRONT_WAIT_BACK_MS	3000
+
+struct xen_drm_front_info {
+	struct xenbus_device *xb_dev;
+	struct xen_drm_front_drm_info *drm_info;
+
+	/* to protect data between backend IO code and interrupt handler */
+	spinlock_t io_lock;
+
+	int num_evt_pairs;
+	struct xen_drm_front_evtchnl_pair *evt_pairs;
+	struct xen_drm_front_cfg cfg;
+
+	/* display buffers */
+	struct list_head dbuf_list;
+};
+
+struct xen_drm_front_drm_pipeline {
+	struct xen_drm_front_drm_info *drm_info;
+
+	int index;
+
+	struct drm_simple_display_pipe pipe;
+
+	struct drm_connector conn;
+	/* These are only for connector mode checking */
+	int width, height;
+
+	struct drm_pending_vblank_event *pending_event;
+
+	struct delayed_work pflip_to_worker;
+
+	bool conn_connected;
+};
+
+struct xen_drm_front_drm_info {
+	struct xen_drm_front_info *front_info;
+	struct drm_device *drm_dev;
+
+	struct xen_drm_front_drm_pipeline pipeline[XEN_DRM_FRONT_MAX_CRTCS];
+};
+
+static inline u64 xen_drm_front_fb_to_cookie(struct drm_framebuffer *fb)
+{
+	return (uintptr_t)fb;
+}
+
+static inline u64 xen_drm_front_dbuf_to_cookie(struct drm_gem_object *gem_obj)
+{
+	return (uintptr_t)gem_obj;
+}
+
+int xen_drm_front_mode_set(struct xen_drm_front_drm_pipeline *pipeline,
+			   u32 x, u32 y, u32 width, u32 height,
+			   u32 bpp, u64 fb_cookie);
+
+int xen_drm_front_dbuf_create(struct xen_drm_front_info *front_info,
+			      u64 dbuf_cookie, u32 width, u32 height,
+			      u32 bpp, u64 size, u32 offset, struct page **pages);
+
+int xen_drm_front_fb_attach(struct xen_drm_front_info *front_info,
+			    u64 dbuf_cookie, u64 fb_cookie, u32 width,
+			    u32 height, u32 pixel_format);
+
+int xen_drm_front_fb_detach(struct xen_drm_front_info *front_info,
+			    u64 fb_cookie);
+
+int xen_drm_front_page_flip(struct xen_drm_front_info *front_info,
+			    int conn_idx, u64 fb_cookie);
+
+void xen_drm_front_on_frame_done(struct xen_drm_front_info *front_info,
+				 int conn_idx, u64 fb_cookie);
+
+void xen_drm_front_gem_object_free(struct drm_gem_object *obj);
+
+#endif /* __XEN_DRM_FRONT_H_ */