From 4eb5cd9c4006848fce00fff39d2b53dc8cad93c7 Mon Sep 17 00:00:00 2001 From: Alessandro Comodi Date: Tue, 1 Mar 2022 09:49:33 +0100 Subject: [PATCH] s7: fix DDR4 mode Signed-off-by: Alessandro Comodi --- litedram/phy/s7ddrphy.py | 108 ++++++++++++++++++++++----------------- 1 file changed, 61 insertions(+), 47 deletions(-) diff --git a/litedram/phy/s7ddrphy.py b/litedram/phy/s7ddrphy.py index 8eee484..ac584b1 100644 --- a/litedram/phy/s7ddrphy.py +++ b/litedram/phy/s7ddrphy.py @@ -47,11 +47,12 @@ class S7DDRPHY(Module, AutoCSR): addressbits = len(pads.a) if memtype == "DDR4": addressbits += 3 # cas_n/ras_n/we_n multiplexed with address - bankbits = len(pads.ba) + bankbits = len(pads.ba) if memtype != "DDR4" else len(pads.ba) + len(pads.bg) nranks = 1 if not hasattr(pads, "cs_n") else len(pads.cs_n) databits = len(pads.dq) nphases = nphases assert databits%8 == 0 + x4_dimm_mode = (databits / len(pads.dqs_p)) == 4 # Parameters ------------------------------------------------------------------------------- iodelay_tap_average = { @@ -162,6 +163,7 @@ class S7DDRPHY(Module, AutoCSR): # DFI Interface ---------------------------------------------------------------------------- self.dfi = dfi = Interface(addressbits, bankbits, nranks, 2*databits, max(4, nphases)) if memtype == "DDR4": + dfi = Interface(addressbits, bankbits, nranks, 2*databits, nphases) self.submodules += DDR4DFIMux(self.dfi, dfi) # # # @@ -213,20 +215,22 @@ class S7DDRPHY(Module, AutoCSR): ) # Commands ----------------------------------------------------------------------------- + pads_ba = Signal(bankbits) commands = { # Pad name: (DFI name, Pad type (required or optional)) "reset_n" : ("reset_n", "optional"), "cs_n" : ("cs_n", "optional"), "a" : ("address", "required"), - "ba" : ("bank" , "required"), + pads_ba : ("bank" , "required"), "ras_n" : ("ras_n" , "required"), "cas_n" : ("cas_n" , "required"), "we_n" : ("we_n" , "required"), "cke" : ("cke" , "optional"), "odt" : ("odt" , "optional"), + "act_n" : ("act_n" , "optional"), } for pad_name, (dfi_name, pad_type) in commands.items(): - pad = getattr(pads, pad_name, None) + pad = pad_name if isinstance(pad_name, Signal) else getattr(pads, pad_name, None) if (pad is None): if (pad_type == "required"): raise ValueError(f"DRAM pad {pad_name} required but not found in pads.") @@ -265,6 +269,10 @@ class S7DDRPHY(Module, AutoCSR): o_DATAOUT = pad[i], ) + self.comb += pads.ba.eq(pads_ba) + if hasattr(pads, "bg"): + self.comb += pads.bg.eq(pads_ba[len(pads.ba):]) + # DQS -------------------------------------------------------------------------------------- dqs_oe = Signal() dqs_preamble = Signal() @@ -279,56 +287,62 @@ class S7DDRPHY(Module, AutoCSR): self.submodules += dqs_oe_delay, dqs_pattern self.comb += dqs_oe_delay.input.eq(dqs_preamble | dqs_oe | dqs_postamble) for i in range(databits//8): - dqs_o_no_delay = Signal() - dqs_o_delayed = Signal() - dqs_t = Signal() dqs_bitslip = BitSlip(8, i = dqs_pattern.o, rst = (self._dly_sel.storage[i] & wdly_dq_bitslip_rst) | self._rst.storage, slp = self._dly_sel.storage[i] & wdly_dq_bitslip, cycles = 1) - self.submodules += dqs_bitslip - self.specials += Instance("OSERDESE2", - p_SERDES_MODE = "MASTER", - p_DATA_WIDTH = 2*nphases, - p_TRISTATE_WIDTH = 1, - p_DATA_RATE_OQ = "DDR", - p_DATA_RATE_TQ = "BUF", - i_RST = ResetSignal("sys") | self._rst.storage, - i_CLK = ClockSignal(ddr_clk) if with_odelay else ClockSignal(ddr_clk+"_dqs"), - i_CLKDIV = ClockSignal("sys"), - **{f"i_D{n+1}": dqs_bitslip.o[n] for n in range(8)}, - i_OCE = 1, - o_OFB = dqs_o_no_delay if with_odelay else Signal(), - o_OQ = Signal() if with_odelay else dqs_o_no_delay, - i_TCE = 1, - i_T1 = ~dqs_oe_delay.output, - o_TQ = dqs_t, - ) - if with_odelay: - self.specials += Instance("ODELAYE2", - p_DELAY_SRC = "ODATAIN", - p_SIGNAL_PATTERN = "DATA", - p_CINVCTRL_SEL = "FALSE", - p_HIGH_PERFORMANCE_MODE = "TRUE", - p_REFCLK_FREQUENCY = iodelay_clk_freq/1e6, - p_PIPE_SEL = "FALSE", - p_ODELAY_TYPE = "VARIABLE", - p_ODELAY_VALUE = half_sys8x_taps, - i_C = ClockSignal("sys"), - i_LD = (self._dly_sel.storage[i] & wdly_dqs_rst) | self._rst.storage, - i_CE = self._dly_sel.storage[i] & wdly_dqs_inc, - i_LDPIPEEN = 0, - i_INC = 1, - o_ODATAIN = dqs_o_no_delay, - o_DATAOUT = dqs_o_delayed + if x4_dimm_mode: + dqs_pads = ((pads.dqs_p[i*2], pads.dqs_n[i*2]), (pads.dqs_p[i*2 + 1], pads.dqs_n[i*2 + 1])) + else: + dqs_pads = ((pads.dqs_p[i], pads.dqs_n[i]), ) + + for j, (dqs_p, dqs_n) in enumerate(dqs_pads): + dqs_o_no_delay = Signal() + dqs_o_delayed = Signal() + dqs_t = Signal() + self.submodules += dqs_bitslip + self.specials += Instance("OSERDESE2", + p_SERDES_MODE = "MASTER", + p_DATA_WIDTH = 2*nphases, + p_TRISTATE_WIDTH = 1, + p_DATA_RATE_OQ = "DDR", + p_DATA_RATE_TQ = "BUF", + i_RST = ResetSignal("sys") | self._rst.storage, + i_CLK = ClockSignal(ddr_clk) if with_odelay else ClockSignal(ddr_clk+"_dqs"), + i_CLKDIV = ClockSignal("sys"), + **{f"i_D{n+1}": dqs_bitslip.o[n] for n in range(8)}, + i_OCE = 1, + o_OFB = dqs_o_no_delay if with_odelay else Signal(), + o_OQ = Signal() if with_odelay else dqs_o_no_delay, + i_TCE = 1, + i_T1 = ~dqs_oe_delay.output, + o_TQ = dqs_t, + ) + if with_odelay: + self.specials += Instance("ODELAYE2", + p_DELAY_SRC = "ODATAIN", + p_SIGNAL_PATTERN = "DATA", + p_CINVCTRL_SEL = "FALSE", + p_HIGH_PERFORMANCE_MODE = "TRUE", + p_REFCLK_FREQUENCY = iodelay_clk_freq/1e6, + p_PIPE_SEL = "FALSE", + p_ODELAY_TYPE = "VARIABLE", + p_ODELAY_VALUE = half_sys8x_taps, + i_C = ClockSignal("sys"), + i_LD = (self._dly_sel.storage[i] & wdly_dqs_rst) | self._rst.storage, + i_CE = self._dly_sel.storage[i] & wdly_dqs_inc, + i_LDPIPEEN = 0, + i_INC = 1, + o_ODATAIN = dqs_o_no_delay, + o_DATAOUT = dqs_o_delayed + ) + self.specials += Instance("IOBUFDS", + i_T = dqs_t, + i_I = dqs_o_delayed if with_odelay else dqs_o_no_delay, + io_IO = dqs_p, + io_IOB = dqs_n, ) - self.specials += Instance("IOBUFDS", - i_T = dqs_t, - i_I = dqs_o_delayed if with_odelay else dqs_o_no_delay, - io_IO = pads.dqs_p[i], - io_IOB = pads.dqs_n[i], - ) # DM --------------------------------------------------------------------------------------- if hasattr(pads, "dm"):