5 files changed, 125 insertions, 1 deletions

diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index 1fafc2f8e8f9..e2336cd2059b 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -37,7 +37,7 @@ drm_kms_helper-y := drm_crtc_helper.o drm_dp_helper.o drm_probe_helper.o \
 		drm_kms_helper_common.o drm_dp_dual_mode_helper.o \
 		drm_simple_kms_helper.o drm_modeset_helper.o \
 		drm_scdc_helper.o drm_gem_framebuffer_helper.o \
-		drm_atomic_state_helper.o
+		drm_atomic_state_helper.o drm_damage_helper.o
 
 drm_kms_helper-$(CONFIG_DRM_PANEL_BRIDGE) += bridge/panel.o
 drm_kms_helper-$(CONFIG_DRM_FBDEV_EMULATION) += drm_fb_helper.o
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 9ac26437051b..48ec378fb27e 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -531,6 +531,8 @@ static int drm_atomic_plane_check(const struct drm_plane_state *old_plane_state,
 	struct drm_crtc *crtc = new_plane_state->crtc;
 	const struct drm_framebuffer *fb = new_plane_state->fb;
 	unsigned int fb_width, fb_height;
+	struct drm_mode_rect *clips;
+	uint32_t num_clips;
 	int ret;
 
 	/* either *both* CRTC and FB must be set, or neither */
@@ -604,6 +606,26 @@ static int drm_atomic_plane_check(const struct drm_plane_state *old_plane_state,
 		return -ENOSPC;
 	}
 
+	clips = drm_plane_get_damage_clips(new_plane_state);
+	num_clips = drm_plane_get_damage_clips_count(new_plane_state);
+
+	/* Make sure damage clips are valid and inside the fb. */
+	while (num_clips > 0) {
+		if (clips->x1 >= clips->x2 ||
+		    clips->y1 >= clips->y2 ||
+		    clips->x1 < 0 ||
+		    clips->y1 < 0 ||
+		    clips->x2 > fb_width ||
+		    clips->y2 > fb_height) {
+			DRM_DEBUG_ATOMIC("[PLANE:%d:%s] invalid damage clip %d %d %d %d\n",
+					 plane->base.id, plane->name, clips->x1,
+					 clips->y1, clips->x2, clips->y2);
+			return -EINVAL;
+		}
+		clips++;
+		num_clips--;
+	}
+
 	if (plane_switching_crtc(old_plane_state, new_plane_state)) {
 		DRM_DEBUG_ATOMIC("[PLANE:%d:%s] switching CRTC directly\n",
 				 plane->base.id, plane->name);
diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
index 86ac33922b09..0876c6941f7a 100644
--- a/drivers/gpu/drm/drm_atomic_uapi.c
+++ b/drivers/gpu/drm/drm_atomic_uapi.c
@@ -513,6 +513,8 @@ static int drm_atomic_plane_set_property(struct drm_plane *plane,
 {
 	struct drm_device *dev = plane->dev;
 	struct drm_mode_config *config = &dev->mode_config;
+	bool replaced = false;
+	int ret;
 
 	if (property == config->prop_fb_id) {
 		struct drm_framebuffer *fb = drm_framebuffer_lookup(dev, NULL, val);
@@ -566,6 +568,14 @@ static int drm_atomic_plane_set_property(struct drm_plane *plane,
 		state->color_encoding = val;
 	} else if (property == plane->color_range_property) {
 		state->color_range = val;
+	} else if (property == config->prop_fb_damage_clips) {
+		ret = drm_atomic_replace_property_blob_from_id(dev,
+					&state->fb_damage_clips,
+					val,
+					-1,
+					sizeof(struct drm_rect),
+					&replaced);
+		return ret;
 	} else if (plane->funcs->atomic_set_property) {
 		return plane->funcs->atomic_set_property(plane, state,
 				property, val);
@@ -621,6 +631,9 @@ drm_atomic_plane_get_property(struct drm_plane *plane,
 		*val = state->color_encoding;
 	} else if (property == plane->color_range_property) {
 		*val = state->color_range;
+	} else if (property == config->prop_fb_damage_clips) {
+		*val = (state->fb_damage_clips) ?
+			state->fb_damage_clips->base.id : 0;
 	} else if (plane->funcs->atomic_get_property) {
 		return plane->funcs->atomic_get_property(plane, state, property, val);
 	} else {
diff --git a/drivers/gpu/drm/drm_damage_helper.c b/drivers/gpu/drm/drm_damage_helper.c
new file mode 100644
index 000000000000..8dc906a489a9
--- /dev/null
+++ b/drivers/gpu/drm/drm_damage_helper.c
@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+/**************************************************************************
+ *
+ * Copyright (c) 2018 VMware, Inc., Palo Alto, CA., USA
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+ * USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors:
+ * Deepak Rawat <drawat@vmware.com>
+ *
+ **************************************************************************/
+
+#include <drm/drm_damage_helper.h>
+
+/**
+ * DOC: overview
+ *
+ * FB_DAMAGE_CLIPS is an optional plane property which provides a means to
+ * specify a list of damage rectangles on a plane in framebuffer coordinates of
+ * the framebuffer attached to the plane. In current context damage is the area
+ * of plane framebuffer that has changed since last plane update (also called
+ * page-flip), irrespective of whether currently attached framebuffer is same as
+ * framebuffer attached during last plane update or not.
+ *
+ * FB_DAMAGE_CLIPS is a hint to kernel which could be helpful for some drivers
+ * to optimize internally especially for virtual devices where each framebuffer
+ * change needs to be transmitted over network, usb, etc.
+ *
+ * Since FB_DAMAGE_CLIPS is a hint so it is an optional property. User-space can
+ * ignore damage clips property and in that case driver will do a full plane
+ * update. In case damage clips are provided then it is guaranteed that the area
+ * inside damage clips will be updated to plane. For efficiency driver can do
+ * full update or can update more than specified in damage clips. Since driver
+ * is free to read more, user-space must always render the entire visible
+ * framebuffer. Otherwise there can be corruptions. Also, if a user-space
+ * provides damage clips which doesn't encompass the actual damage to
+ * framebuffer (since last plane update) can result in incorrect rendering.
+ *
+ * FB_DAMAGE_CLIPS is a blob property with the layout of blob data is simply an
+ * array of &drm_mode_rect. Unlike plane &drm_plane_state.src coordinates,
+ * damage clips are not in 16.16 fixed point. Similar to plane src in
+ * framebuffer, damage clips cannot be negative. In damage clip, x1/y1 are
+ * inclusive and x2/y2 are exclusive. While kernel does not error for overlapped
+ * damage clips, it is strongly discouraged.
+ *
+ * Drivers that are interested in damage interface for plane should enable
+ * FB_DAMAGE_CLIPS property by calling drm_plane_enable_fb_damage_clips().
+ */
+
+/**
+ * drm_plane_enable_fb_damage_clips - Enables plane fb damage clips property.
+ * @plane: Plane on which to enable damage clips property.
+ *
+ * This function lets driver to enable the damage clips property on a plane.
+ */
+void drm_plane_enable_fb_damage_clips(struct drm_plane *plane)
+{
+	struct drm_device *dev = plane->dev;
+	struct drm_mode_config *config = &dev->mode_config;
+
+	drm_object_attach_property(&plane->base, config->prop_fb_damage_clips,
+				   0);
+}
+EXPORT_SYMBOL(drm_plane_enable_fb_damage_clips);
diff --git a/drivers/gpu/drm/drm_mode_config.c b/drivers/gpu/drm/drm_mode_config.c
index ee80788f2c40..05cd5e9857e4 100644
--- a/drivers/gpu/drm/drm_mode_config.c
+++ b/drivers/gpu/drm/drm_mode_config.c
@@ -297,6 +297,12 @@ static int drm_mode_create_standard_properties(struct drm_device *dev)
 		return -ENOMEM;
 	dev->mode_config.prop_crtc_id = prop;
 
+	prop = drm_property_create(dev, DRM_MODE_PROP_BLOB, "FB_DAMAGE_CLIPS",
+				   0);
+	if (!prop)
+		return -ENOMEM;
+	dev->mode_config.prop_fb_damage_clips = prop;
+
 	prop = drm_property_create_bool(dev, DRM_MODE_PROP_ATOMIC,
 			"ACTIVE");
 	if (!prop)