GX_XY
wiifb_gx_bp_load(sc, 0x59000000 | GX_XY(xo >> 1, yo >> 1));
wiifb_gx_bp_load(sc, 0x49000000 | GX_XY(0, 0));
GX_XY(WIIFB_RGB_WIDTH - 1, WIIFB_RGB_HEIGHT - 1));