Re: [PATCH] Add virtio gpu driver.

[Gerd Hoffmann]

  Hi,

> I guess I didn't do a good job at looking at your v2: Cursor is still
> using legacy interfaces and not a proper plane. Would be awesome if
> you could fix that up. Atomic drivers really shouldn't use the legacy
> cursor interfaces any more at all.
> -Daniel

Figured that one for the most part, see attached draft.

The only thing I'm wondering is how the hotspot is handled.
drm_mode_cursor_universal doesn't even look at req->hot_{x,y}.

/me looks confused.

cheers,
  Gerd

From fb1d0700a46d850ec9f931304a9e99854a3ce5e9 Mon Sep 17 00:00:00 2001
From: Gerd Hoffmann <kraxel@xxxxxxxxxx>
Date: Thu, 26 May 2016 11:42:52 +0200
Subject: [PATCH] [wip] virtio-gpu: switch to atomic cursor interfaces

Signed-off-by: Gerd Hoffmann <kraxel@xxxxxxxxxx>
---
 drivers/gpu/drm/virtio/virtgpu_display.c | 102 +++-----------------------
 drivers/gpu/drm/virtio/virtgpu_drv.h     |   1 +
 drivers/gpu/drm/virtio/virtgpu_plane.c   | 122 ++++++++++++++++++++++++-------
 3 files changed, 109 insertions(+), 116 deletions(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_display.c b/drivers/gpu/drm/virtio/virtgpu_display.c
index 5990cab..d6b16d1 100644
--- a/drivers/gpu/drm/virtio/virtgpu_display.c
+++ b/drivers/gpu/drm/virtio/virtgpu_display.c
@@ -29,8 +29,8 @@
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_atomic_helper.h>
 
-#define XRES_MIN   320
-#define YRES_MIN   200
+#define XRES_MIN    32
+#define YRES_MIN    32
 
 #define XRES_DEF  1024
 #define YRES_DEF   768
@@ -38,86 +38,6 @@
 #define XRES_MAX  8192
 #define YRES_MAX  8192
 
-static void
-virtio_gpu_hide_cursor(struct virtio_gpu_device *vgdev,
-		       struct virtio_gpu_output *output)
-{
-	output->cursor.hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_UPDATE_CURSOR);
-	output->cursor.resource_id = 0;
-	virtio_gpu_cursor_ping(vgdev, output);
-}
-
-static int virtio_gpu_crtc_cursor_set(struct drm_crtc *crtc,
-				      struct drm_file *file_priv,
-				      uint32_t handle,
-				      uint32_t width,
-				      uint32_t height,
-				      int32_t hot_x, int32_t hot_y)
-{
-	struct virtio_gpu_device *vgdev = crtc->dev->dev_private;
-	struct virtio_gpu_output *output =
-		container_of(crtc, struct virtio_gpu_output, crtc);
-	struct drm_gem_object *gobj = NULL;
-	struct virtio_gpu_object *qobj = NULL;
-	struct virtio_gpu_fence *fence = NULL;
-	int ret = 0;
-
-	if (handle == 0) {
-		virtio_gpu_hide_cursor(vgdev, output);
-		return 0;
-	}
-
-	/* lookup the cursor */
-	gobj = drm_gem_object_lookup(crtc->dev, file_priv, handle);
-	if (gobj == NULL)
-		return -ENOENT;
-
-	qobj = gem_to_virtio_gpu_obj(gobj);
-
-	if (!qobj->hw_res_handle) {
-		ret = -EINVAL;
-		goto out;
-	}
-
-	virtio_gpu_cmd_transfer_to_host_2d(vgdev, qobj->hw_res_handle, 0,
-					   cpu_to_le32(64),
-					   cpu_to_le32(64),
-					   0, 0, &fence);
-	ret = virtio_gpu_object_reserve(qobj, false);
-	if (!ret) {
-		reservation_object_add_excl_fence(qobj->tbo.resv,
-						  &fence->f);
-		fence_put(&fence->f);
-		virtio_gpu_object_unreserve(qobj);
-		virtio_gpu_object_wait(qobj, false);
-	}
-
-	output->cursor.hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_UPDATE_CURSOR);
-	output->cursor.resource_id = cpu_to_le32(qobj->hw_res_handle);
-	output->cursor.hot_x = cpu_to_le32(hot_x);
-	output->cursor.hot_y = cpu_to_le32(hot_y);
-	virtio_gpu_cursor_ping(vgdev, output);
-	ret = 0;
-
-out:
-	drm_gem_object_unreference_unlocked(gobj);
-	return ret;
-}
-
-static int virtio_gpu_crtc_cursor_move(struct drm_crtc *crtc,
-				    int x, int y)
-{
-	struct virtio_gpu_device *vgdev = crtc->dev->dev_private;
-	struct virtio_gpu_output *output =
-		container_of(crtc, struct virtio_gpu_output, crtc);
-
-	output->cursor.hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_MOVE_CURSOR);
-	output->cursor.pos.x = cpu_to_le32(x);
-	output->cursor.pos.y = cpu_to_le32(y);
-	virtio_gpu_cursor_ping(vgdev, output);
-	return 0;
-}
-
 static int virtio_gpu_page_flip(struct drm_crtc *crtc,
 				struct drm_framebuffer *fb,
 				struct drm_pending_vblank_event *event,
@@ -164,8 +84,6 @@ static int virtio_gpu_page_flip(struct drm_crtc *crtc,
 }
 
 static const struct drm_crtc_funcs virtio_gpu_crtc_funcs = {
-	.cursor_set2            = virtio_gpu_crtc_cursor_set,
-	.cursor_move            = virtio_gpu_crtc_cursor_move,
 	.set_config             = drm_atomic_helper_set_config,
 	.destroy                = drm_crtc_cleanup,
 
@@ -406,7 +324,7 @@ static int vgdev_output_init(struct virtio_gpu_device *vgdev, int index)
 	struct drm_connector *connector = &output->conn;
 	struct drm_encoder *encoder = &output->enc;
 	struct drm_crtc *crtc = &output->crtc;
-	struct drm_plane *plane;
+	struct drm_plane *primary, *cursor;
 
 	output->index = index;
 	if (index == 0) {
@@ -415,14 +333,18 @@ static int vgdev_output_init(struct virtio_gpu_device *vgdev, int index)
 		output->info.r.height = cpu_to_le32(YRES_DEF);
 	}
 
-	plane = virtio_gpu_plane_init(vgdev, index);
-	if (IS_ERR(plane))
-		return PTR_ERR(plane);
-	drm_crtc_init_with_planes(dev, crtc, plane, NULL,
+	primary = virtio_gpu_plane_init(vgdev, DRM_PLANE_TYPE_PRIMARY, index);
+	if (IS_ERR(primary))
+		return PTR_ERR(primary);
+	cursor = virtio_gpu_plane_init(vgdev, DRM_PLANE_TYPE_CURSOR, index);
+	if (IS_ERR(cursor))
+		return PTR_ERR(cursor);
+	drm_crtc_init_with_planes(dev, crtc, primary, cursor,
 				  &virtio_gpu_crtc_funcs, NULL);
 	drm_mode_crtc_set_gamma_size(crtc, 256);
 	drm_crtc_helper_add(crtc, &virtio_gpu_crtc_helper_funcs);
-	plane->crtc = crtc;
+	primary->crtc = crtc;
+	cursor->crtc = crtc;
 
 	drm_connector_init(dev, connector, &virtio_gpu_connector_funcs,
 			   DRM_MODE_CONNECTOR_VIRTUAL);
diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h
index 8f486f4..a1f7e9d 100644
--- a/drivers/gpu/drm/virtio/virtgpu_drv.h
+++ b/drivers/gpu/drm/virtio/virtgpu_drv.h
@@ -335,6 +335,7 @@ void virtio_gpu_modeset_fini(struct virtio_gpu_device *vgdev);
 
 /* virtio_gpu_plane.c */
 struct drm_plane *virtio_gpu_plane_init(struct virtio_gpu_device *vgdev,
+					enum drm_plane_type type,
 					int index);
 
 /* virtio_gpu_ttm.c */
diff --git a/drivers/gpu/drm/virtio/virtgpu_plane.c b/drivers/gpu/drm/virtio/virtgpu_plane.c
index 70b44a2..d68270f 100644
--- a/drivers/gpu/drm/virtio/virtgpu_plane.c
+++ b/drivers/gpu/drm/virtio/virtgpu_plane.c
@@ -38,6 +38,10 @@ static const uint32_t virtio_gpu_formats[] = {
 	DRM_FORMAT_ABGR8888,
 };
 
+static const uint32_t virtio_gpu_cursor_formats[] = {
+	DRM_FORMAT_ARGB8888,
+};
+
 static void virtio_gpu_plane_destroy(struct drm_plane *plane)
 {
 	kfree(plane);
@@ -63,39 +67,97 @@ static void virtio_gpu_plane_atomic_update(struct drm_plane *plane,
 {
 	struct drm_device *dev = plane->dev;
 	struct virtio_gpu_device *vgdev = dev->dev_private;
-	struct virtio_gpu_output *output = drm_crtc_to_virtio_gpu_output(plane->crtc);
+	struct virtio_gpu_output *output = NULL;
 	struct virtio_gpu_framebuffer *vgfb;
-	struct virtio_gpu_object *bo;
+	struct virtio_gpu_fence *fence = NULL;
+	struct virtio_gpu_object *bo = NULL;
 	uint32_t handle;
+	int ret = 0;
+
+	if (plane->state->crtc)
+		output = drm_crtc_to_virtio_gpu_output(plane->state->crtc);
+	if (old_state->crtc)
+		output = drm_crtc_to_virtio_gpu_output(old_state->crtc);
+	WARN_ON(!output);
 
 	if (plane->state->fb) {
 		vgfb = to_virtio_gpu_framebuffer(plane->state->fb);
 		bo = gem_to_virtio_gpu_obj(vgfb->obj);
 		handle = bo->hw_res_handle;
-		if (bo->dumb) {
-			virtio_gpu_cmd_transfer_to_host_2d
-				(vgdev, handle, 0,
-				 cpu_to_le32(plane->state->crtc_w),
-				 cpu_to_le32(plane->state->crtc_h),
-				 plane->state->crtc_x, plane->state->crtc_y, NULL);
-		}
 	} else {
 		handle = 0;
 	}
 
-	DRM_DEBUG("handle 0x%x, crtc %dx%d+%d+%d\n", handle,
-		  plane->state->crtc_w, plane->state->crtc_h,
-		  plane->state->crtc_x, plane->state->crtc_y);
-	virtio_gpu_cmd_set_scanout(vgdev, output->index, handle,
-				   plane->state->crtc_w,
-				   plane->state->crtc_h,
-				   plane->state->crtc_x,
-				   plane->state->crtc_y);
-	virtio_gpu_cmd_resource_flush(vgdev, handle,
-				      plane->state->crtc_x,
-				      plane->state->crtc_y,
-				      plane->state->crtc_w,
-				      plane->state->crtc_h);
+	switch (plane->type) {
+	case DRM_PLANE_TYPE_CURSOR:
+		if (bo && bo->dumb && (plane->state->fb != old_state->fb)) {
+			/* new cursor -- update & wait */
+			virtio_gpu_cmd_transfer_to_host_2d
+				(vgdev, handle, 0,
+				 cpu_to_le32(plane->state->crtc_w),
+				 cpu_to_le32(plane->state->crtc_h),
+				 0, 0, &fence);
+			ret = virtio_gpu_object_reserve(bo, false);
+			if (!ret) {
+				reservation_object_add_excl_fence(bo->tbo.resv,
+								  &fence->f);
+				fence_put(&fence->f);
+				fence = NULL;
+				virtio_gpu_object_unreserve(bo);
+				virtio_gpu_object_wait(bo, false);
+			}
+		}
+
+		if (plane->state->fb != old_state->fb) {
+			DRM_DEBUG("cursor update, handle %d, +%d+%d\n", handle,
+				  plane->state->crtc_x,
+				  plane->state->crtc_y);
+			output->cursor.hdr.type =
+				cpu_to_le32(VIRTIO_GPU_CMD_UPDATE_CURSOR);
+			output->cursor.resource_id = cpu_to_le32(handle);
+#if 0
+			output->cursor.hot_x = cpu_to_le32(hot_x);
+			output->cursor.hot_y = cpu_to_le32(hot_y);
+#endif
+		} else {
+			DRM_DEBUG("cursor move +%d+%d\n",
+				  plane->state->crtc_x,
+				  plane->state->crtc_y);
+			output->cursor.hdr.type =
+				cpu_to_le32(VIRTIO_GPU_CMD_MOVE_CURSOR);
+		}
+		output->cursor.pos.x = cpu_to_le32(plane->state->crtc_x);
+		output->cursor.pos.y = cpu_to_le32(plane->state->crtc_y);
+		virtio_gpu_cursor_ping(vgdev, output);
+		break;
+
+	case DRM_PLANE_TYPE_PRIMARY:
+		DRM_DEBUG("primary, handle 0x%x, crtc %dx%d+%d+%d\n", handle,
+			  plane->state->crtc_w, plane->state->crtc_h,
+			  plane->state->crtc_x, plane->state->crtc_y);
+		if (bo && bo->dumb) {
+			virtio_gpu_cmd_transfer_to_host_2d
+				(vgdev, handle, 0,
+				 cpu_to_le32(plane->state->crtc_w),
+				 cpu_to_le32(plane->state->crtc_h),
+				 plane->state->crtc_x, plane->state->crtc_y,
+				 &fence);
+		}
+		virtio_gpu_cmd_set_scanout(vgdev, output->index, handle,
+					   plane->state->crtc_w,
+					   plane->state->crtc_h,
+					   plane->state->crtc_x,
+					   plane->state->crtc_y);
+		virtio_gpu_cmd_resource_flush(vgdev, handle,
+					      plane->state->crtc_x,
+					      plane->state->crtc_y,
+					      plane->state->crtc_w,
+					      plane->state->crtc_h);
+		break;
+
+	default:
+		WARN_ON(true);
+	}
 }
 
 
@@ -105,21 +167,29 @@ static const struct drm_plane_helper_funcs virtio_gpu_plane_helper_funcs = {
 };
 
 struct drm_plane *virtio_gpu_plane_init(struct virtio_gpu_device *vgdev,
+					enum drm_plane_type type,
 					int index)
 {
 	struct drm_device *dev = vgdev->ddev;
 	struct drm_plane *plane;
-	int ret;
+	const uint32_t *formats;
+	int ret, nformats;
 
 	plane = kzalloc(sizeof(*plane), GFP_KERNEL);
 	if (!plane)
 		return ERR_PTR(-ENOMEM);
 
+	if (type == DRM_PLANE_TYPE_CURSOR) {
+		formats = virtio_gpu_cursor_formats;
+		nformats = ARRAY_SIZE(virtio_gpu_cursor_formats);
+	} else {
+		formats = virtio_gpu_formats;
+		nformats = ARRAY_SIZE(virtio_gpu_formats);
+	}
 	ret = drm_universal_plane_init(dev, plane, 1 << index,
 				       &virtio_gpu_plane_funcs,
-				       virtio_gpu_formats,
-				       ARRAY_SIZE(virtio_gpu_formats),
-				       DRM_PLANE_TYPE_PRIMARY, NULL);
+				       formats, nformats,
+				       type, NULL);
 	if (ret)
 		goto err_plane_init;
 
-- 
1.8.3.1