drm/tegra: plane: Support horizontal reflection

Support horizontal reflection mode which will allow to support 180°
rotation mode when combined with the vertical reflection.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/gpu/drm/tegra/dc.c

@@ -368,6 +368,12 @@ static void tegra_dc_setup_window(struct tegra_plane *plane,
 	h_size = window->src.w * bpp;
 	v_size = window->src.h;
 
+	if (window->reflect_x)
+		h_offset += (window->src.w - 1) * bpp;
+
+	if (window->reflect_y)
+		v_offset += window->src.h - 1;
+
 	value = V_PRESCALED_SIZE(v_size) | H_PRESCALED_SIZE(h_size);
 	tegra_plane_writel(plane, value, DC_WIN_PRESCALED_SIZE);
 
@@ -404,9 +410,6 @@ static void tegra_dc_setup_window(struct tegra_plane *plane,
 		tegra_plane_writel(plane, window->stride[0], DC_WIN_LINE_STRIDE);
 	}
 
-	if (window->reflect_y)
-		v_offset += window->src.h - 1;
-
 	tegra_plane_writel(plane, h_offset, DC_WINBUF_ADDR_H_OFFSET);
 	tegra_plane_writel(plane, v_offset, DC_WINBUF_ADDR_V_OFFSET);
 
@@ -470,6 +473,9 @@ static void tegra_dc_setup_window(struct tegra_plane *plane,
 		value |= COLOR_EXPAND;
 	}
 
+	if (window->reflect_x)
+		value |= H_DIRECTION;
+
 	if (window->reflect_y)
 		value |= V_DIRECTION;
 
@@ -601,7 +607,10 @@ static int tegra_plane_atomic_check(struct drm_plane *plane,
 				    struct drm_plane_state *state)
 {
 	struct tegra_plane_state *plane_state = to_tegra_plane_state(state);
-	unsigned int rotation = DRM_MODE_ROTATE_0 | DRM_MODE_REFLECT_Y;
+	unsigned int supported_rotation = DRM_MODE_ROTATE_0 |
+					  DRM_MODE_REFLECT_X |
+					  DRM_MODE_REFLECT_Y;
+	unsigned int rotation = state->rotation;
 	struct tegra_bo_tiling *tiling = &plane_state->tiling;
 	struct tegra_plane *tegra = to_tegra_plane(plane);
 	struct tegra_dc *dc = to_tegra_dc(state->crtc);
@@ -639,7 +648,21 @@ static int tegra_plane_atomic_check(struct drm_plane *plane,
 		return -EINVAL;
 	}
 
-	rotation = drm_rotation_simplify(state->rotation, rotation);
+	/*
+	 * Older userspace used custom BO flag in order to specify the Y
+	 * reflection, while modern userspace uses the generic DRM rotation
+	 * property in order to achieve the same result.  The legacy BO flag
+	 * duplicates the DRM rotation property when both are set.
+	 */
+	if (tegra_fb_is_bottom_up(state->fb))
+		rotation |= DRM_MODE_REFLECT_Y;
+
+	rotation = drm_rotation_simplify(rotation, supported_rotation);
+
+	if (rotation & DRM_MODE_REFLECT_X)
+		plane_state->reflect_x = true;
+	else
+		plane_state->reflect_x = false;
 
 	if (rotation & DRM_MODE_REFLECT_Y)
 		plane_state->reflect_y = true;
@@ -706,7 +729,8 @@ static void tegra_plane_atomic_update(struct drm_plane *plane,
 	window.dst.w = drm_rect_width(&plane->state->dst);
 	window.dst.h = drm_rect_height(&plane->state->dst);
 	window.bits_per_pixel = fb->format->cpp[0] * 8;
-	window.reflect_y = tegra_fb_is_bottom_up(fb) || state->reflect_y;
+	window.reflect_x = state->reflect_x;
+	window.reflect_y = state->reflect_y;
 
 	/* copy from state */
 	window.zpos = plane->state->normalized_zpos;
@@ -792,6 +816,7 @@ static struct drm_plane *tegra_primary_plane_create(struct drm_device *drm,
 	err = drm_plane_create_rotation_property(&plane->base,
 						 DRM_MODE_ROTATE_0,
 						 DRM_MODE_ROTATE_0 |
+						 DRM_MODE_REFLECT_X |
 						 DRM_MODE_REFLECT_Y);
 	if (err < 0)
 		dev_err(dc->dev, "failed to create rotation property: %d\n",
@@ -1080,6 +1105,7 @@ static struct drm_plane *tegra_dc_overlay_plane_create(struct drm_device *drm,
 	err = drm_plane_create_rotation_property(&plane->base,
 						 DRM_MODE_ROTATE_0,
 						 DRM_MODE_ROTATE_0 |
+						 DRM_MODE_REFLECT_X |
 						 DRM_MODE_REFLECT_Y);
 	if (err < 0)
 		dev_err(dc->dev, "failed to create rotation property: %d\n",