from migen.fhdl.std import * from migen.genlib.cdc import MultiReg, PulseSynchronizer from migen.bank.description import * class DataCapture(Module, AutoCSR): def __init__(self, pad_p, pad_n, ntbits): self.serdesstrobe = Signal() self.d = Signal(10) self._dly_ctl = CSR(6) self._dly_busy = CSRStatus(2) self._phase = CSRStatus(2) self._phase_reset = CSR() ### # IO pad_se = Signal() self.specials += Instance("IBUFDS", i_I=pad_p, i_IB=pad_n, o_O=pad_se) pad_delayed_master = Signal() pad_delayed_slave = Signal() delay_inc = Signal() delay_ce = Signal() delay_master_cal = Signal() delay_master_rst = Signal() delay_master_busy = Signal() delay_slave_cal = Signal() delay_slave_rst = Signal() delay_slave_busy = Signal() self.specials += Instance("IODELAY2", p_SERDES_MODE="MASTER", p_DELAY_SRC="IDATAIN", p_IDELAY_TYPE="DIFF_PHASE_DETECTOR", p_COUNTER_WRAPAROUND="STAY_AT_LIMIT", p_DATA_RATE="SDR", i_IDATAIN=pad_se, o_DATAOUT=pad_delayed_master, i_CLK=ClockSignal("pix2x"), i_IOCLK0=ClockSignal("pix10x"), i_INC=delay_inc, i_CE=delay_ce, i_CAL=delay_master_cal, i_RST=delay_master_rst, o_BUSY=delay_master_busy, i_T=1) self.specials += Instance("IODELAY2", p_SERDES_MODE="SLAVE", p_DELAY_SRC="IDATAIN", p_IDELAY_TYPE="DIFF_PHASE_DETECTOR", p_COUNTER_WRAPAROUND="WRAPAROUND", p_DATA_RATE="SDR", i_IDATAIN=pad_se, o_DATAOUT=pad_delayed_slave, i_CLK=ClockSignal("pix2x"), i_IOCLK0=ClockSignal("pix10x"), i_INC=delay_inc, i_CE=delay_ce, i_CAL=delay_slave_cal, i_RST=delay_slave_rst, o_BUSY=delay_slave_busy, i_T=1) dsr2 = Signal(5) pd_valid = Signal() pd_incdec = Signal() pd_edge = Signal() pd_cascade = Signal() self.specials += Instance("ISERDES2", p_SERDES_MODE="MASTER", p_BITSLIP_ENABLE="FALSE", p_DATA_RATE="SDR", p_DATA_WIDTH=5, p_INTERFACE_TYPE="RETIMED", i_D=pad_delayed_master, o_Q4=dsr2[4], o_Q3=dsr2[3], o_Q2=dsr2[2], o_Q1=dsr2[1], i_BITSLIP=0, i_CE0=1, i_RST=0, i_CLK0=ClockSignal("pix10x"), i_CLKDIV=ClockSignal("pix2x"), i_IOCE=self.serdesstrobe, o_VALID=pd_valid, o_INCDEC=pd_incdec, i_SHIFTIN=pd_edge, o_SHIFTOUT=pd_cascade) self.specials += Instance("ISERDES2", p_SERDES_MODE="SLAVE", p_BITSLIP_ENABLE="FALSE", p_DATA_RATE="SDR", p_DATA_WIDTH=5, p_INTERFACE_TYPE="RETIMED", i_D=pad_delayed_slave, o_Q4=dsr2[0], i_BITSLIP=0, i_CE0=1, i_RST=0, i_CLK0=ClockSignal("pix10x"), i_CLKDIV=ClockSignal("pix2x"), i_IOCE=self.serdesstrobe, i_SHIFTIN=pd_cascade, o_SHIFTOUT=pd_edge) # Phase error accumulator lateness = Signal(ntbits, reset=2**(ntbits - 1)) too_late = Signal() too_early = Signal() reset_lateness = Signal() self.comb += [ too_late.eq(lateness == (2**ntbits - 1)), too_early.eq(lateness == 0) ] self.sync.pix2x += [ If(reset_lateness, lateness.eq(2**(ntbits - 1)) ).Elif(~delay_master_busy & ~delay_slave_busy & ~too_late & ~too_early, If(pd_valid & pd_incdec, lateness.eq(lateness - 1)), If(pd_valid & ~pd_incdec, lateness.eq(lateness + 1)) ) ] # Delay control self.submodules.delay_master_done = PulseSynchronizer("pix2x", "sys") delay_master_pending = Signal() self.sync.pix2x += [ self.delay_master_done.i.eq(0), If(~delay_master_pending, If(delay_master_cal | delay_ce, delay_master_pending.eq(1)) ).Else( If(~delay_master_busy, self.delay_master_done.i.eq(1), delay_master_pending.eq(0) ) ) ] self.submodules.delay_slave_done = PulseSynchronizer("pix2x", "sys") delay_slave_pending = Signal() self.sync.pix2x += [ self.delay_slave_done.i.eq(0), If(~delay_slave_pending, If(delay_slave_cal | delay_ce, delay_slave_pending.eq(1)) ).Else( If(~delay_slave_busy, self.delay_slave_done.i.eq(1), delay_slave_pending.eq(0) ) ) ] self.submodules.do_delay_master_cal = PulseSynchronizer("sys", "pix2x") self.submodules.do_delay_master_rst = PulseSynchronizer("sys", "pix2x") self.submodules.do_delay_slave_cal = PulseSynchronizer("sys", "pix2x") self.submodules.do_delay_slave_rst = PulseSynchronizer("sys", "pix2x") self.submodules.do_delay_inc = PulseSynchronizer("sys", "pix2x") self.submodules.do_delay_dec = PulseSynchronizer("sys", "pix2x") self.comb += [ delay_master_cal.eq(self.do_delay_master_cal.o), delay_master_rst.eq(self.do_delay_master_rst.o), delay_slave_cal.eq(self.do_delay_slave_cal.o), delay_slave_rst.eq(self.do_delay_slave_rst.o), delay_inc.eq(self.do_delay_inc.o), delay_ce.eq(self.do_delay_inc.o | self.do_delay_dec.o), ] sys_delay_master_pending = Signal() self.sync += [ If(self.do_delay_master_cal.i | self.do_delay_inc.i | self.do_delay_dec.i, sys_delay_master_pending.eq(1) ).Elif(self.delay_master_done.o, sys_delay_master_pending.eq(0) ) ] sys_delay_slave_pending = Signal() self.sync += [ If(self.do_delay_slave_cal.i | self.do_delay_inc.i | self.do_delay_dec.i, sys_delay_slave_pending.eq(1) ).Elif(self.delay_slave_done.o, sys_delay_slave_pending.eq(0) ) ] self.comb += [ self.do_delay_master_cal.i.eq(self._dly_ctl.re & self._dly_ctl.r[0]), self.do_delay_master_rst.i.eq(self._dly_ctl.re & self._dly_ctl.r[1]), self.do_delay_slave_cal.i.eq(self._dly_ctl.re & self._dly_ctl.r[2]), self.do_delay_slave_rst.i.eq(self._dly_ctl.re & self._dly_ctl.r[3]), self.do_delay_inc.i.eq(self._dly_ctl.re & self._dly_ctl.r[4]), self.do_delay_dec.i.eq(self._dly_ctl.re & self._dly_ctl.r[5]), self._dly_busy.status.eq(Cat(sys_delay_master_pending, sys_delay_slave_pending)) ] # Phase detector control self.specials += MultiReg(Cat(too_late, too_early), self._phase.status) self.submodules.do_reset_lateness = PulseSynchronizer("sys", "pix2x") self.comb += [ reset_lateness.eq(self.do_reset_lateness.o), self.do_reset_lateness.i.eq(self._phase_reset.re) ] # 5:10 deserialization dsr = Signal(10) self.sync.pix2x += dsr.eq(Cat(dsr[5:], dsr2)) self.sync.pix += self.d.eq(dsr)