SPCNTR
intel_de_write_fw(display, SPCNTR(pipe, plane_id), sprctl);
intel_de_write_fw(display, SPCNTR(pipe, plane_id), 0);
error->ctl = intel_de_read(display, SPCNTR(crtc->pipe, plane->id));
ret = intel_de_read(display, SPCNTR(plane->pipe, plane_id)) & SP_ENABLE;