PTP_EGR_TS_FIFO_SIG_BYTES_MASK
val &= ~(PTP_EGR_TS_FIFO_SIG_BYTES_MASK | PTP_EGR_TS_FIFO_THRESH_MASK);
#define PTP_EGR_TS_FIFO_SIG_BYTES(x) ((x) & PTP_EGR_TS_FIFO_SIG_BYTES_MASK)