RING_WAIT_SEMAPHORE
ENGINE_READ(engine, RING_CTL) & (RING_WAIT | RING_WAIT_SEMAPHORE) ? " [waiting]" : "");
if ((regs[CTX_RING_CTL] & ~(RING_WAIT | RING_WAIT_SEMAPHORE)) !=
if (val & RING_WAIT_SEMAPHORE)
busy = val & (RING_WAIT_SEMAPHORE | RING_WAIT);