drm/radeon: Hide the HW cursor while it's out of bounds

Fixes hangs in that case under some circumstances.

v2:
* Only use non-0 x/yorigin if the cursor is (partially) outside of the
  top/left edge of the total surface with AVIVO/DCE

Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=1000433
Cc: stable@vger.kernel.org
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com> (v1)
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/radeon_cursor.c

@@ -90,6 +90,9 @@ static void radeon_show_cursor(struct drm_crtc *crtc)
 	struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
 	struct radeon_device *rdev = crtc->dev->dev_private;
 
+	if (radeon_crtc->cursor_out_of_bounds)
+		return;
+
 	if (ASIC_IS_DCE4(rdev)) {
 		WREG32(EVERGREEN_CUR_SURFACE_ADDRESS_HIGH + radeon_crtc->crtc_offset,
 		       upper_32_bits(radeon_crtc->cursor_addr));
@@ -151,16 +154,17 @@ static int radeon_cursor_move_locked(struct drm_crtc *crtc, int x, int y)
 		x += crtc->x;
 		y += crtc->y;
 	}
-	DRM_DEBUG("x %d y %d c->x %d c->y %d\n", x, y, crtc->x, crtc->y);
 
-	if (x < 0) {
+	if (x < 0)
 		xorigin = min(-x, radeon_crtc->max_cursor_width - 1);
-		x = 0;
+	if (y < 0)
-	}
-	if (y < 0) {
 		yorigin = min(-y, radeon_crtc->max_cursor_height - 1);
-		y = 0;
+
+	if (!ASIC_IS_AVIVO(rdev)) {
+		x += crtc->x;
+		y += crtc->y;
 	}
+	DRM_DEBUG("x %d y %d c->x %d c->y %d\n", x, y, crtc->x, crtc->y);
 
 	/* fixed on DCE6 and newer */
 	if (ASIC_IS_AVIVO(rdev) && !ASIC_IS_DCE6(rdev)) {
@@ -183,27 +187,31 @@ static int radeon_cursor_move_locked(struct drm_crtc *crtc, int x, int y)
 		if (i > 1) {
 			int cursor_end, frame_end;
 
-			cursor_end = x - xorigin + w;
+			cursor_end = x + w;
 			frame_end = crtc->x + crtc->mode.crtc_hdisplay;
 			if (cursor_end >= frame_end) {
 				w = w - (cursor_end - frame_end);
 				if (!(frame_end & 0x7f))
 					w--;
-			} else {
+			} else if (cursor_end <= 0) {
-				if (!(cursor_end & 0x7f))
+				goto out_of_bounds;
-					w--;
+			} else if (!(cursor_end & 0x7f)) {
+				w--;
 			}
 			if (w <= 0) {
-				w = 1;
+				goto out_of_bounds;
-				cursor_end = x - xorigin + w;
-				if (!(cursor_end & 0x7f)) {
-					x--;
-					WARN_ON_ONCE(x < 0);
-				}
 			}
 		}
 	}
 
+	if (x <= (crtc->x - w) || y <= (crtc->y - radeon_crtc->cursor_height) ||
+	    x >= (crtc->x + crtc->mode.crtc_hdisplay) ||
+	    y >= (crtc->y + crtc->mode.crtc_vdisplay))
+		goto out_of_bounds;
+
+	x += xorigin;
+	y += yorigin;
+
 	if (ASIC_IS_DCE4(rdev)) {
 		WREG32(EVERGREEN_CUR_POSITION + radeon_crtc->crtc_offset, (x << 16) | y);
 		WREG32(EVERGREEN_CUR_HOT_SPOT + radeon_crtc->crtc_offset, (xorigin << 16) | yorigin);
@@ -215,6 +223,9 @@ static int radeon_cursor_move_locked(struct drm_crtc *crtc, int x, int y)
 		WREG32(AVIVO_D1CUR_SIZE + radeon_crtc->crtc_offset,
 		       ((w - 1) << 16) | (radeon_crtc->cursor_height - 1));
 	} else {
+		x -= crtc->x;
+		y -= crtc->y;
+
 		if (crtc->mode.flags & DRM_MODE_FLAG_DBLSCAN)
 			y *= 2;
 
@@ -232,6 +243,19 @@ static int radeon_cursor_move_locked(struct drm_crtc *crtc, int x, int y)
 		       yorigin * 256);
 	}
 
+	if (radeon_crtc->cursor_out_of_bounds) {
+		radeon_crtc->cursor_out_of_bounds = false;
+		if (radeon_crtc->cursor_bo)
+			radeon_show_cursor(crtc);
+	}
+
+	return 0;
+
+ out_of_bounds:
+	if (!radeon_crtc->cursor_out_of_bounds) {
+		radeon_hide_cursor(crtc);
+		radeon_crtc->cursor_out_of_bounds = true;
+	}
 	return 0;
 }
 
@@ -308,12 +332,12 @@ int radeon_crtc_cursor_set2(struct drm_crtc *crtc,
 		x = radeon_crtc->cursor_x + radeon_crtc->cursor_hot_x - hot_x;
 		y = radeon_crtc->cursor_y + radeon_crtc->cursor_hot_y - hot_y;
 
-		radeon_cursor_move_locked(crtc, x, y);
-
 		radeon_crtc->cursor_width = width;
 		radeon_crtc->cursor_height = height;
 		radeon_crtc->cursor_hot_x = hot_x;
 		radeon_crtc->cursor_hot_y = hot_y;
+
+		radeon_cursor_move_locked(crtc, x, y);
 	}
 
 	radeon_show_cursor(crtc);

drivers/gpu/drm/radeon/radeon_mode.h

@@ -330,6 +330,7 @@ struct radeon_crtc {
 	u16 lut_r[256], lut_g[256], lut_b[256];
 	bool enabled;
 	bool can_tile;
+	bool cursor_out_of_bounds;
 	uint32_t crtc_offset;
 	struct drm_gem_object *cursor_bo;
 	uint64_t cursor_addr;