drm/vkms: Add cursor plane support

Add cursor plane support and update vkms_plane_atomic_check to enable
positioning cursor plane.

Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/c69078820eacf3246fa77beb0c6227b692cc5e82.1536210181.git.hamohammed.sa@gmail.com

drivers/gpu/drm/vkms/vkms_drv.h

@@ -7,8 +7,8 @@
 #include <drm/drm_encoder.h>
 #include <linux/hrtimer.h>
 
-#define XRES_MIN    32
-#define YRES_MIN    32
+#define XRES_MIN    20
+#define YRES_MIN    20
 
 #define XRES_DEF  1024
 #define YRES_DEF   768
@@ -20,6 +20,10 @@ static const u32 vkms_formats[] = {
 	DRM_FORMAT_XRGB8888,
 };
 
+static const u32 vkms_cursor_formats[] = {
+	DRM_FORMAT_ARGB8888,
+};
+
 struct vkms_crc_data {
 	struct drm_rect src;
 	struct drm_framebuffer fb;
@@ -104,7 +108,8 @@ bool vkms_get_vblank_timestamp(struct drm_device *dev, unsigned int pipe,
 
 int vkms_output_init(struct vkms_device *vkmsdev);
 
-struct drm_plane *vkms_plane_init(struct vkms_device *vkmsdev);
+struct drm_plane *vkms_plane_init(struct vkms_device *vkmsdev,
+				  enum drm_plane_type type);
 
 /* Gem stuff */
 struct drm_gem_object *vkms_gem_create(struct drm_device *dev,

drivers/gpu/drm/vkms/vkms_output.c

@@ -49,14 +49,20 @@ int vkms_output_init(struct vkms_device *vkmsdev)
 	struct drm_connector *connector = &output->connector;
 	struct drm_encoder *encoder = &output->encoder;
 	struct drm_crtc *crtc = &output->crtc;
-	struct drm_plane *primary;
+	struct drm_plane *primary, *cursor = NULL;
 	int ret;
 
-	primary = vkms_plane_init(vkmsdev);
+	primary = vkms_plane_init(vkmsdev, DRM_PLANE_TYPE_PRIMARY);
 	if (IS_ERR(primary))
 		return PTR_ERR(primary);
 
-	ret = vkms_crtc_init(dev, crtc, primary, NULL);
+	cursor = vkms_plane_init(vkmsdev, DRM_PLANE_TYPE_CURSOR);
+	if (IS_ERR(cursor)) {
+		ret = PTR_ERR(cursor);
+		goto err_cursor;
+	}
+
+	ret = vkms_crtc_init(dev, crtc, primary, cursor);
 	if (ret)
 		goto err_crtc;
 
@@ -106,6 +112,10 @@ err_connector:
 	drm_crtc_cleanup(crtc);
 
 err_crtc:
+	drm_plane_cleanup(cursor);
+
+err_cursor:
 	drm_plane_cleanup(primary);
+
 	return ret;
 }

drivers/gpu/drm/vkms/vkms_plane.c

@@ -81,8 +81,8 @@ static const struct drm_plane_funcs vkms_plane_funcs = {
 	.atomic_destroy_state	= vkms_plane_destroy_state,
 };
 
-static void vkms_primary_plane_update(struct drm_plane *plane,
-				      struct drm_plane_state *old_state)
+static void vkms_plane_atomic_update(struct drm_plane *plane,
+				     struct drm_plane_state *old_state)
 {
 	struct vkms_plane_state *vkms_plane_state;
 	struct vkms_crc_data *crc_data;
@@ -101,6 +101,7 @@ static int vkms_plane_atomic_check(struct drm_plane *plane,
 				   struct drm_plane_state *state)
 {
 	struct drm_crtc_state *crtc_state;
+	bool can_position = false;
 	int ret;
 
 	if (!state->fb | !state->crtc)
@@ -110,15 +111,18 @@ static int vkms_plane_atomic_check(struct drm_plane *plane,
 	if (IS_ERR(crtc_state))
 		return PTR_ERR(crtc_state);
 
+	if (plane->type == DRM_PLANE_TYPE_CURSOR)
+		can_position = true;
+
 	ret = drm_atomic_helper_check_plane_state(state, crtc_state,
 						  DRM_PLANE_HELPER_NO_SCALING,
 						  DRM_PLANE_HELPER_NO_SCALING,
-						  false, true);
+						  can_position, true);
 	if (ret != 0)
 		return ret;
 
 	/* for now primary plane must be visible and full screen */
-	if (!state->visible)
+	if (!state->visible && !can_position)
 		return -EINVAL;
 
 	return 0;
@@ -156,15 +160,17 @@ static void vkms_cleanup_fb(struct drm_plane *plane,
 }
 
 static const struct drm_plane_helper_funcs vkms_primary_helper_funcs = {
-	.atomic_update		= vkms_primary_plane_update,
+	.atomic_update		= vkms_plane_atomic_update,
 	.atomic_check		= vkms_plane_atomic_check,
 	.prepare_fb		= vkms_prepare_fb,
 	.cleanup_fb		= vkms_cleanup_fb,
 };
 
-struct drm_plane *vkms_plane_init(struct vkms_device *vkmsdev)
+struct drm_plane *vkms_plane_init(struct vkms_device *vkmsdev,
+				  enum drm_plane_type type)
 {
 	struct drm_device *dev = &vkmsdev->drm;
+	const struct drm_plane_helper_funcs *funcs;
 	struct drm_plane *plane;
 	const u32 *formats;
 	int ret, nformats;
@@ -173,19 +179,26 @@ struct drm_plane *vkms_plane_init(struct vkms_device *vkmsdev)
 	if (!plane)
 		return ERR_PTR(-ENOMEM);
 
-	formats = vkms_formats;
-	nformats = ARRAY_SIZE(vkms_formats);
+	if (type == DRM_PLANE_TYPE_CURSOR) {
+		formats = vkms_cursor_formats;
+		nformats = ARRAY_SIZE(vkms_cursor_formats);
+		funcs = &vkms_primary_helper_funcs;
+	} else {
+		formats = vkms_formats;
+		nformats = ARRAY_SIZE(vkms_formats);
+		funcs = &vkms_primary_helper_funcs;
+	}
 
 	ret = drm_universal_plane_init(dev, plane, 0,
 				       &vkms_plane_funcs,
 				       formats, nformats,
-				       NULL, DRM_PLANE_TYPE_PRIMARY, NULL);
+				       NULL, type, NULL);
 	if (ret) {
 		kfree(plane);
 		return ERR_PTR(ret);
 	}
 
-	drm_plane_helper_add(plane, &vkms_primary_helper_funcs);
+	drm_plane_helper_add(plane, funcs);
 
 	return plane;
 }