5 files changed, 45 insertions, 14 deletions

diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c
index 48b1cf0f4ec8..e49523866e1d 100644
--- a/drivers/gpu/drm/vkms/vkms_composer.c
+++ b/drivers/gpu/drm/vkms/vkms_composer.c
@@ -176,11 +176,12 @@ static void compose_plane(struct vkms_composer *primary_composer,
 
 static int compose_active_planes(void **vaddr_out,
 				 struct vkms_composer *primary_composer,
-				 struct vkms_composer *cursor_composer)
+				 struct vkms_crtc_state *crtc_state)
 {
 	struct drm_framebuffer *fb = &primary_composer->fb;
 	struct drm_gem_object *gem_obj = drm_gem_fb_get_obj(fb, 0);
 	struct drm_gem_shmem_object *shmem_obj = to_drm_gem_shmem_obj(gem_obj);
+	int i;
 
 	if (!*vaddr_out) {
 		*vaddr_out = kzalloc(shmem_obj->base.size, GFP_KERNEL);
@@ -195,8 +196,14 @@ static int compose_active_planes(void **vaddr_out,
 
 	memcpy(*vaddr_out, shmem_obj->vaddr, shmem_obj->base.size);
 
-	if (cursor_composer)
-		compose_plane(primary_composer, cursor_composer, *vaddr_out);
+	/* If there are other planes besides primary, we consider the active
+	 * planes should be in z-order and compose them associatively:
+	 * ((primary <- overlay) <- cursor)
+	 */
+	for (i = 1; i < crtc_state->num_active_planes; i++)
+		compose_plane(primary_composer,
+			      crtc_state->active_planes[i]->composer,
+			      *vaddr_out);
 
 	return 0;
 }
@@ -218,7 +225,7 @@ void vkms_composer_worker(struct work_struct *work)
 	struct drm_crtc *crtc = crtc_state->base.crtc;
 	struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
 	struct vkms_composer *primary_composer = NULL;
-	struct vkms_composer *cursor_composer = NULL;
+	struct vkms_plane_state *act_plane = NULL;
 	bool crc_pending, wb_pending;
 	void *vaddr_out = NULL;
 	u32 crc32 = 0;
@@ -242,11 +249,11 @@ void vkms_composer_worker(struct work_struct *work)
 	if (!crc_pending)
 		return;
 
-	if (crtc_state->num_active_planes >= 1)
-		primary_composer = crtc_state->active_planes[0]->composer;
-
-	if (crtc_state->num_active_planes == 2)
-		cursor_composer = crtc_state->active_planes[1]->composer;
+	if (crtc_state->num_active_planes >= 1) {
+		act_plane = crtc_state->active_planes[0];
+		if (act_plane->base.plane->type == DRM_PLANE_TYPE_PRIMARY)
+			primary_composer = act_plane->composer;
+	}
 
 	if (!primary_composer)
 		return;
@@ -255,7 +262,7 @@ void vkms_composer_worker(struct work_struct *work)
 		vaddr_out = crtc_state->active_writeback;
 
 	ret = compose_active_planes(&vaddr_out, primary_composer,
-				    cursor_composer);
+				    crtc_state);
 	if (ret) {
 		if (ret == -EINVAL && !wb_pending)
 			kfree(vaddr_out);
diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c
index 2173b82606f6..027ffe759440 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.c
+++ b/drivers/gpu/drm/vkms/vkms_drv.c
@@ -44,6 +44,10 @@ static bool enable_writeback = true;
 module_param_named(enable_writeback, enable_writeback, bool, 0444);
 MODULE_PARM_DESC(enable_writeback, "Enable/Disable writeback connector support");
 
+static bool enable_overlay;
+module_param_named(enable_overlay, enable_overlay, bool, 0444);
+MODULE_PARM_DESC(enable_overlay, "Enable/Disable overlay support");
+
 DEFINE_DRM_GEM_FOPS(vkms_driver_fops);
 
 static void vkms_release(struct drm_device *dev)
@@ -198,6 +202,7 @@ static int __init vkms_init(void)
 
 	config->cursor = enable_cursor;
 	config->writeback = enable_writeback;
+	config->overlay = enable_overlay;
 
 	return vkms_create(config);
 }
diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
index 70fb79621617..ac8c9c2fa4ed 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.h
+++ b/drivers/gpu/drm/vkms/vkms_drv.h
@@ -89,6 +89,7 @@ struct vkms_device;
 struct vkms_config {
 	bool writeback;
 	bool cursor;
+	bool overlay;
 	/* only set when instantiated */
 	struct vkms_device *dev;
 };
diff --git a/drivers/gpu/drm/vkms/vkms_output.c b/drivers/gpu/drm/vkms/vkms_output.c
index 6979fbc7f821..04406bd3ff02 100644
--- a/drivers/gpu/drm/vkms/vkms_output.c
+++ b/drivers/gpu/drm/vkms/vkms_output.c
@@ -39,7 +39,7 @@ int vkms_output_init(struct vkms_device *vkmsdev, int index)
 	struct drm_connector *connector = &output->connector;
 	struct drm_encoder *encoder = &output->encoder;
 	struct drm_crtc *crtc = &output->crtc;
-	struct vkms_plane *primary, *cursor = NULL;
+	struct vkms_plane *primary, *cursor = NULL, *overlay = NULL;
 	int ret;
 	int writeback;
 
@@ -47,6 +47,15 @@ int vkms_output_init(struct vkms_device *vkmsdev, int index)
 	if (IS_ERR(primary))
 		return PTR_ERR(primary);
 
+	if (vkmsdev->config->overlay) {
+		overlay = vkms_plane_init(vkmsdev, DRM_PLANE_TYPE_OVERLAY, index);
+		if (IS_ERR(overlay))
+			return PTR_ERR(overlay);
+
+		if (!overlay->base.possible_crtcs)
+			overlay->base.possible_crtcs = drm_crtc_mask(crtc);
+	}
+
 	if (vkmsdev->config->cursor) {
 		cursor = vkms_plane_init(vkmsdev, DRM_PLANE_TYPE_CURSOR, index);
 		if (IS_ERR(cursor))
diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c
index da4251aff67f..107521ace597 100644
--- a/drivers/gpu/drm/vkms/vkms_plane.c
+++ b/drivers/gpu/drm/vkms/vkms_plane.c
@@ -133,7 +133,7 @@ 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)
+	if (plane->type != DRM_PLANE_TYPE_PRIMARY)
 		can_position = true;
 
 	ret = drm_atomic_helper_check_plane_state(new_plane_state, crtc_state,
@@ -200,14 +200,23 @@ struct vkms_plane *vkms_plane_init(struct vkms_device *vkmsdev,
 	const u32 *formats;
 	int nformats;
 
-	if (type == DRM_PLANE_TYPE_CURSOR) {
+	switch (type) {
+	case DRM_PLANE_TYPE_PRIMARY:
+		formats = vkms_formats;
+		nformats = ARRAY_SIZE(vkms_formats);
+		funcs = &vkms_primary_helper_funcs;
+		break;
+	case DRM_PLANE_TYPE_CURSOR:
+	case DRM_PLANE_TYPE_OVERLAY:
 		formats = vkms_plane_formats;
 		nformats = ARRAY_SIZE(vkms_plane_formats);
 		funcs = &vkms_primary_helper_funcs;
-	} else {
+		break;
+	default:
 		formats = vkms_formats;
 		nformats = ARRAY_SIZE(vkms_formats);
 		funcs = &vkms_primary_helper_funcs;
+		break;
 	}
 
 	plane = drmm_universal_plane_alloc(dev, struct vkms_plane, base, 1 << index,