[PATCH 3/3] drm/virtio: Probe and implement VIRTIO_GPU_F_EXPLICIT_FLUSH feature

Vivek Kasireddy vivek.kasireddy at intel.com
Tue May 11 08:36:10 UTC 2021


If this feature is available, a fence will be associated with the
scanout buffer and a dma_fence_wait will be performed as part of
plane update.

Cc: Gerd Hoffmann <kraxel at redhat.com>
Signed-off-by: Vivek Kasireddy <vivek.kasireddy at intel.com>
---
 drivers/gpu/drm/virtio/virtgpu_debugfs.c |  1 +
 drivers/gpu/drm/virtio/virtgpu_drv.c     |  1 +
 drivers/gpu/drm/virtio/virtgpu_drv.h     |  1 +
 drivers/gpu/drm/virtio/virtgpu_kms.c     |  9 ++++-
 drivers/gpu/drm/virtio/virtgpu_plane.c   | 51 ++++++++++++++++++++----
 5 files changed, 53 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_debugfs.c b/drivers/gpu/drm/virtio/virtgpu_debugfs.c
index c2b20e0ee030..4c258299752b 100644
--- a/drivers/gpu/drm/virtio/virtgpu_debugfs.c
+++ b/drivers/gpu/drm/virtio/virtgpu_debugfs.c
@@ -52,6 +52,7 @@ static int virtio_gpu_features(struct seq_file *m, void *data)
 			    vgdev->has_resource_assign_uuid);
 
 	virtio_gpu_add_bool(m, "blob resources", vgdev->has_resource_blob);
+	virtio_gpu_add_bool(m, "explicit flush", vgdev->has_explicit_flush);
 	virtio_gpu_add_int(m, "cap sets", vgdev->num_capsets);
 	virtio_gpu_add_int(m, "scanouts", vgdev->num_scanouts);
 	if (vgdev->host_visible_region.len) {
diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.c b/drivers/gpu/drm/virtio/virtgpu_drv.c
index a21dc3ad6f88..b003523e876e 100644
--- a/drivers/gpu/drm/virtio/virtgpu_drv.c
+++ b/drivers/gpu/drm/virtio/virtgpu_drv.c
@@ -166,6 +166,7 @@ static unsigned int features[] = {
 	VIRTIO_GPU_F_EDID,
 	VIRTIO_GPU_F_RESOURCE_UUID,
 	VIRTIO_GPU_F_RESOURCE_BLOB,
+	VIRTIO_GPU_F_EXPLICIT_FLUSH,
 };
 static struct virtio_driver virtio_gpu_driver = {
 	.feature_table = features,
diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h
index f77d196ccc8f..72552618d3c3 100644
--- a/drivers/gpu/drm/virtio/virtgpu_drv.h
+++ b/drivers/gpu/drm/virtio/virtgpu_drv.h
@@ -233,6 +233,7 @@ struct virtio_gpu_device {
 	bool has_resource_assign_uuid;
 	bool has_resource_blob;
 	bool has_host_visible;
+	bool has_explicit_flush;
 	struct virtio_shm_region host_visible_region;
 	struct drm_mm host_visible_mm;
 
diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c b/drivers/gpu/drm/virtio/virtgpu_kms.c
index b375394193be..d6ff9cb8f97e 100644
--- a/drivers/gpu/drm/virtio/virtgpu_kms.c
+++ b/drivers/gpu/drm/virtio/virtgpu_kms.c
@@ -156,6 +156,9 @@ int virtio_gpu_init(struct drm_device *dev)
 	if (virtio_has_feature(vgdev->vdev, VIRTIO_GPU_F_RESOURCE_BLOB)) {
 		vgdev->has_resource_blob = true;
 	}
+	if (virtio_has_feature(vgdev->vdev, VIRTIO_GPU_F_EXPLICIT_FLUSH)) {
+		vgdev->has_explicit_flush = true;
+	}
 	if (virtio_get_shm_region(vgdev->vdev, &vgdev->host_visible_region,
 				  VIRTIO_GPU_SHM_ID_HOST_VISIBLE)) {
 		if (!devm_request_mem_region(&vgdev->vdev->dev,
@@ -176,11 +179,13 @@ int virtio_gpu_init(struct drm_device *dev)
 			    (unsigned long)vgdev->host_visible_region.len);
 	}
 
-	DRM_INFO("features: %cvirgl %cedid %cresource_blob %chost_visible\n",
+	DRM_INFO("features: %cvirgl %cedid %cresource_blob %chost_visible\
+		 %cexplicit_flush\n",
 		 vgdev->has_virgl_3d    ? '+' : '-',
 		 vgdev->has_edid        ? '+' : '-',
 		 vgdev->has_resource_blob ? '+' : '-',
-		 vgdev->has_host_visible ? '+' : '-');
+		 vgdev->has_host_visible ? '+' : '-',
+		 vgdev->has_explicit_flush ? '+' : '-');
 
 	ret = virtio_find_vqs(vgdev->vdev, 2, vqs, callbacks, names, NULL);
 	if (ret) {
diff --git a/drivers/gpu/drm/virtio/virtgpu_plane.c b/drivers/gpu/drm/virtio/virtgpu_plane.c
index 4e1b17548007..9ae2ec2e9da7 100644
--- a/drivers/gpu/drm/virtio/virtgpu_plane.c
+++ b/drivers/gpu/drm/virtio/virtgpu_plane.c
@@ -129,6 +129,30 @@ static void virtio_gpu_update_dumb_bo(struct virtio_gpu_device *vgdev,
 					   objs, NULL);
 }
 
+static void virtio_gpu_fb_wait_flush(struct drm_plane *plane)
+{
+	struct drm_device *dev = plane->dev;
+	struct virtio_gpu_device *vgdev = dev->dev_private;
+	struct virtio_gpu_framebuffer *vgfb;
+
+	vgfb = to_virtio_gpu_framebuffer(plane->state->fb);
+	if (vgfb && vgfb->fence) {
+		struct virtio_gpu_object_array *objs;
+
+		objs = virtio_gpu_array_alloc(1);
+		if (!objs)
+			return;
+		virtio_gpu_array_add_obj(objs, vgfb->base.obj[0]);
+		virtio_gpu_array_lock_resv(objs);
+		virtio_gpu_cmd_wait_flush(vgdev, objs, vgfb->fence);
+		virtio_gpu_notify(vgdev);
+
+		dma_fence_wait(&vgfb->fence->f, true);
+		dma_fence_put(&vgfb->fence->f);
+		vgfb->fence = NULL;
+	}
+}
+
 static void virtio_gpu_primary_plane_update(struct drm_plane *plane,
 					    struct drm_atomic_state *state)
 {
@@ -204,17 +228,22 @@ static void virtio_gpu_primary_plane_update(struct drm_plane *plane,
 				      rect.x2 - rect.x1,
 				      rect.y2 - rect.y1);
 	virtio_gpu_notify(vgdev);
+
+	if (vgdev->has_explicit_flush && bo->guest_blob)
+		virtio_gpu_fb_wait_flush(plane);
 }
 
-static int virtio_gpu_cursor_prepare_fb(struct drm_plane *plane,
-					struct drm_plane_state *new_state)
+static int virtio_gpu_plane_prepare_fb(struct drm_plane *plane,
+				       struct drm_plane_state *new_state)
 {
 	struct drm_device *dev = plane->dev;
 	struct virtio_gpu_device *vgdev = dev->dev_private;
 	struct virtio_gpu_framebuffer *vgfb;
 	struct virtio_gpu_object *bo;
 
-	if (!new_state->fb)
+	if (!new_state->fb ||
+	    (plane->type == DRM_PLANE_TYPE_PRIMARY &&
+	    !vgdev->has_explicit_flush))
 		return 0;
 
 	vgfb = to_virtio_gpu_framebuffer(new_state->fb);
@@ -228,12 +257,16 @@ static int virtio_gpu_cursor_prepare_fb(struct drm_plane *plane,
 	return 0;
 }
 
-static void virtio_gpu_cursor_cleanup_fb(struct drm_plane *plane,
-					 struct drm_plane_state *old_state)
+static void virtio_gpu_plane_cleanup_fb(struct drm_plane *plane,
+					struct drm_plane_state *old_state)
 {
+	struct drm_device *dev = plane->dev;
+	struct virtio_gpu_device *vgdev = dev->dev_private;
 	struct virtio_gpu_framebuffer *vgfb;
 
-	if (!plane->state->fb)
+	if (!plane->state->fb ||
+	    (plane->type == DRM_PLANE_TYPE_PRIMARY &&
+	    !vgdev->has_explicit_flush))
 		return;
 
 	vgfb = to_virtio_gpu_framebuffer(plane->state->fb);
@@ -321,13 +354,15 @@ static void virtio_gpu_cursor_plane_update(struct drm_plane *plane,
 }
 
 static const struct drm_plane_helper_funcs virtio_gpu_primary_helper_funcs = {
+	.prepare_fb		= virtio_gpu_plane_prepare_fb,
+	.cleanup_fb		= virtio_gpu_plane_cleanup_fb,
 	.atomic_check		= virtio_gpu_plane_atomic_check,
 	.atomic_update		= virtio_gpu_primary_plane_update,
 };
 
 static const struct drm_plane_helper_funcs virtio_gpu_cursor_helper_funcs = {
-	.prepare_fb		= virtio_gpu_cursor_prepare_fb,
-	.cleanup_fb		= virtio_gpu_cursor_cleanup_fb,
+	.prepare_fb		= virtio_gpu_plane_prepare_fb,
+	.cleanup_fb		= virtio_gpu_plane_cleanup_fb,
 	.atomic_check		= virtio_gpu_plane_atomic_check,
 	.atomic_update		= virtio_gpu_cursor_plane_update,
 };
-- 
2.30.2



More information about the dri-devel mailing list