From: Sebastien Bourdeauducq Date: Thu, 16 Feb 2012 17:02:37 +0000 (+0100) Subject: Generate all clocks for the DDR PHY X-Git-Tag: 24jan2021_ls180~3240 X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=72f9af9d90ee437aa0a4892628624e044fe43e84;p=litex.git Generate all clocks for the DDR PHY --- diff --git a/build.py b/build.py index 7559f11d..fae1a93a 100644 --- a/build.py +++ b/build.py @@ -10,7 +10,7 @@ def add_core_dir(d): def add_core_files(d, files): for f in files: verilog_sources.append(os.path.join("verilog", d, f)) -add_core_dir("m1reset") +add_core_dir("m1crg") add_core_files("lm32", ["lm32_cpu.v", "lm32_instruction_unit.v", "lm32_decoder.v", "lm32_load_store_unit.v", "lm32_adder.v", "lm32_addsub.v", "lm32_logic_op.v", "lm32_shifter.v", "lm32_multiplier_spartan6.v", "lm32_mc_arithmetic.v", @@ -59,4 +59,4 @@ os.system("map -ol high -w soc.ngd") os.system("par -ol high -w soc.ncd soc-routed.ncd") # bitgen -os.system("bitgen -g LCK_cycle:6 -g Binary:Yes -g INIT_9K:Yes -w soc-routed.ncd soc.bit") +os.system("bitgen -g Binary:Yes -g INIT_9K:Yes -w soc-routed.ncd soc.bit") diff --git a/constraints.py b/constraints.py index f37b6b27..91b44dd6 100644 --- a/constraints.py +++ b/constraints.py @@ -1,4 +1,4 @@ -def get(ns, clkfx_sys, reset0, norflash0, uart0): +def get(ns, crg0, norflash0, uart0): constraints = [] def add(signal, pin, vec=-1, iostandard="LVCMOS33", extra=""): constraints.append((ns.get_name(signal), vec, pin, iostandard, extra)) @@ -8,12 +8,12 @@ def get(ns, clkfx_sys, reset0, norflash0, uart0): add(signal, p, i, iostandard, extra) i += 1 - add(clkfx_sys.clkin, "AB11", extra="TNM_NET = \"GRPclk50\"") - - add(reset0.trigger_reset, "AA4") - add(reset0.ac97_rst_n, "D6") - add(reset0.videoin_rst_n, "W17") - add(reset0.flash_rst_n, "P22", extra="SLEW = FAST | DRIVE = 8") + add(crg0.clkin, "AB11", extra="TNM_NET = \"GRPclk50\"") + add(crg0.ac97_rst_n, "D6") + add(crg0.videoin_rst_n, "W17") + add(crg0.flash_rst_n, "P22", extra="SLEW = FAST | DRIVE = 8") + add(crg0.rd_clk_lb, "K5") + add(crg0.trigger_reset, "AA4") add_vec(norflash0.adr, ["L22", "L20", "K22", "K21", "J19", "H20", "F22", "F21", "K17", "J17", "E22", "E20", "H18", "H19", "F20", diff --git a/milkymist/m1crg/__init__.py b/milkymist/m1crg/__init__.py new file mode 100644 index 00000000..ad51a7c2 --- /dev/null +++ b/milkymist/m1crg/__init__.py @@ -0,0 +1,51 @@ +from fractions import Fraction + +from migen.fhdl.structure import * + +class M1CRG: + def __init__(self, infreq, outfreq1x): + self.clkin = Signal() + self.trigger_reset = Signal() + + generated = [] + for name in [ + "sys_clk", + "sys_rst", + "ac97_rst_n", + "videoin_rst_n", + "flash_rst_n", + "clk2x_90", + "clk4x_wr_left", + "clk4x_wr_strb_left", + "clk4x_wr_right", + "clk4x_wr_strb_right", + "clk4x_rd_left", + "clk4x_rd_strb_left", + "clk4x_rd_right", + "clk4x_rd_strb_right" + ]: + s = Signal(name=name) + setattr(self, name, s) + generated.append((name, s)) + + self.rd_clk_lb = Signal() + + ratio = Fraction(outfreq1x)/Fraction(infreq) + in_period = float(Fraction(1000000000)/Fraction(infreq)) + + self._inst = Instance("m1crg", + generated, + [ + ("clkin", self.clkin), + ("trigger_reset", self.trigger_reset), + ("rd_clk_lb", self.rd_clk_lb) # TODO: inout + ], [ + ("in_period", in_period), + ("f_mult", ratio.numerator), + ("f_div", ratio.denominator) + ] + ) + + def get_fragment(self): + return Fragment(instances=[self._inst], + pads={self.clkin, self.ac97_rst_n, self.videoin_rst_n, self.flash_rst_n, self.rd_clk_lb}) diff --git a/milkymist/m1reset/__init__.py b/milkymist/m1reset/__init__.py deleted file mode 100644 index 64b973b9..00000000 --- a/milkymist/m1reset/__init__.py +++ /dev/null @@ -1,20 +0,0 @@ -from migen.fhdl.structure import * - -class M1Reset: - def __init__(self): - self.trigger_reset = Signal() - self.sys_rst = Signal() - self.ac97_rst_n = Signal() - self.videoin_rst_n = Signal() - self.flash_rst_n = Signal() - self._inst = Instance("m1reset", - [("sys_rst", self.sys_rst), - ("ac97_rst_n", self.ac97_rst_n), - ("videoin_rst_n", self.videoin_rst_n), - ("flash_rst_n", self.flash_rst_n)], - [("trigger_reset", self.trigger_reset)], - clkport="sys_clk") - - def get_fragment(self): - return Fragment(instances=[self._inst], - pads={self.ac97_rst_n, self.videoin_rst_n, self.flash_rst_n}) diff --git a/top.py b/top.py index 50c8f0bd..c46eda58 100644 --- a/top.py +++ b/top.py @@ -1,12 +1,14 @@ +from fractions import Fraction + from migen.fhdl.structure import * from migen.fhdl import verilog, autofragment from migen.bus import wishbone, asmibus, wishbone2asmi, csr, wishbone2csr -from milkymist import m1reset, clkfx, lm32, norflash, uart, sram +from milkymist import m1crg, lm32, norflash, uart, sram#, s6ddrphy import constraints MHz = 1000000 -clk_freq = 80*MHz +clk_freq = (83 + Fraction(1, 3))*MHz sram_size = 4096 # in bytes l2_size = 8192 # in bytes @@ -14,7 +16,8 @@ def get(): # # ASMI # - asmihub0 = asmibus.Hub(24, 64, 8) # TODO: get hub from memory controller + #ddrphy0 = s6ddrphy.S6DDRPHY(13, 2, 128) + asmihub0 = asmibus.Hub(23, 128, 12) # TODO: get hub from memory controller asmiport_wb = asmihub0.get_port() asmihub0.finalize() @@ -62,15 +65,14 @@ def get(): # # Housekeeping # - clkfx_sys = clkfx.ClkFX(50*MHz, clk_freq) - reset0 = m1reset.M1Reset() + crg0 = m1crg.M1CRG(50*MHz, clk_freq) frag = autofragment.from_local() + interrupts src_verilog, vns = verilog.convert(frag, - {clkfx_sys.clkin, reset0.trigger_reset}, + {crg0.trigger_reset}, name="soc", - clk_signal=clkfx_sys.clkout, - rst_signal=reset0.sys_rst, + clk_signal=crg0.sys_clk, + rst_signal=crg0.sys_rst, return_ns=True) - src_ucf = constraints.get(vns, clkfx_sys, reset0, norflash0, uart0) + src_ucf = constraints.get(vns, crg0, norflash0, uart0) return (src_verilog, src_ucf) diff --git a/verilog/m1crg/m1crg.v b/verilog/m1crg/m1crg.v new file mode 100644 index 00000000..e885a0c0 --- /dev/null +++ b/verilog/m1crg/m1crg.v @@ -0,0 +1,424 @@ +/* + * Milkymist-NG SoC + * Copyright (C) 2007, 2008, 2009, 2010, 2011, 2012 Sebastien Bourdeauducq + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, version 3 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +module m1crg #( + parameter in_period = 0.0, + parameter f_mult = 0, + parameter f_div = 0, + parameter clk2x_period = (in_period*f_div)/(2.0*f_mult) +) ( + input clkin, + input trigger_reset, + + output sys_clk, + output reg sys_rst, + + /* Reset off-chip devices */ + output ac97_rst_n, + output videoin_rst_n, + output flash_rst_n, + + /* DDR PHY clocks and reset */ + output clk2x_90, + output clk4x_wr_left, + output clk4x_wr_strb_left, + output clk4x_wr_right, + output clk4x_wr_strb_right, + output clk4x_rd_left, + output clk4x_rd_strb_left, + output clk4x_rd_right, + output clk4x_rd_strb_right, + inout rd_clk_lb /* < unconnected clock pin for read clock PLL loopback */ +); + +/* + * Reset + */ + +wire reset_n; + +reg [19:0] rst_debounce; +always @(posedge sys_clk, negedge reset_n) begin + if(~reset_n) begin + rst_debounce <= 20'hFFFFF; + sys_rst <= 1'b1; + end else begin + if(trigger_reset) + rst_debounce <= 20'hFFFFF; + else if(rst_debounce != 20'd0) + rst_debounce <= rst_debounce - 20'd1; + sys_rst <= rst_debounce != 20'd0; + end +end + +assign ac97_rst_n = ~sys_rst; +assign videoin_rst_n = ~sys_rst; + +/* + * We must release the Flash reset before the system reset + * because the Flash needs some time to come out of reset + * and the CPU begins fetching instructions from it + * as soon as the system reset is released. + * From datasheet, minimum reset pulse width is 100ns + * and reset-to-read time is 150ns. + */ + +reg [7:0] flash_rstcounter; + +always @(posedge sys_clk, negedge reset_n) begin + if(~reset_n) begin + flash_rstcounter <= 8'd0; + end else begin + if(trigger_reset) + flash_rstcounter <= 8'd0; + else if(~flash_rstcounter[7]) + flash_rstcounter <= flash_rstcounter + 8'd1; + end +end + +assign flash_rst_n = flash_rstcounter[7]; + +/* + * Clock management. Largely taken from the NWL reference design. + */ + +wire sdr_clkin; +wire clkdiv; + +IBUF #( + .IOSTANDARD("DEFAULT") +) clk2_iob ( + .I(clkin), + .O(sdr_clkin) +); + +BUFIO2 #( + .DIVIDE(1), + .DIVIDE_BYPASS("FALSE"), + .I_INVERT("FALSE") +) bufio2_inst2 ( + .I(sdr_clkin), + .IOCLK(), + .DIVCLK(clkdiv), + .SERDESSTROBE() +); + +wire pll1_lckd; +wire buf_pll1_fb_out; +wire pll1out0; +wire pll1out1; +wire pll1out2; +wire pll1out3; + +PLL_ADV #( + .BANDWIDTH("OPTIMIZED"), + .CLKFBOUT_MULT(4*f_mult), + .CLKFBOUT_PHASE(0.0), + .CLKIN1_PERIOD(in_period), + .CLKIN2_PERIOD(in_period), + .CLKOUT0_DIVIDE(f_div), + .CLKOUT0_DUTY_CYCLE(0.5), + .CLKOUT0_PHASE(0), + .CLKOUT1_DIVIDE(f_div), + .CLKOUT1_DUTY_CYCLE(0.5), + .CLKOUT1_PHASE(0), + .CLKOUT2_DIVIDE(4*f_div), + .CLKOUT2_DUTY_CYCLE(0.5), + .CLKOUT2_PHASE(0.0), + .CLKOUT3_DIVIDE(2*f_div), + .CLKOUT3_DUTY_CYCLE(0.5), + .CLKOUT3_PHASE(90), + .CLKOUT4_DIVIDE(7), + .CLKOUT4_DUTY_CYCLE(0.5), + .CLKOUT4_PHASE(0), + .CLKOUT5_DIVIDE(7), + .CLKOUT5_DUTY_CYCLE(0.5), + .CLKOUT5_PHASE(0.0), + .COMPENSATION("INTERNAL"), + .DIVCLK_DIVIDE(1), + .REF_JITTER(0.100), + .CLK_FEEDBACK("CLKFBOUT"), + .SIM_DEVICE("SPARTAN6") +) pll1 ( + .CLKFBDCM(), + .CLKFBOUT(buf_pll1_fb_out), + .CLKOUT0(pll1out0), /* < x4 180 clock for transmitter */ + .CLKOUT1(pll1out1), /* < x4 180 clock for transmitter */ + .CLKOUT2(pll1out2), /* < x1 clock for memory controller */ + .CLKOUT3(pll1out3), /* < x2 90 clock to generate memory clock, clock DQS and memory address and control signals. */ + .CLKOUT4(), + .CLKOUT5(), + .CLKOUTDCM0(), + .CLKOUTDCM1(), + .CLKOUTDCM2(), + .CLKOUTDCM3(), + .CLKOUTDCM4(), + .CLKOUTDCM5(), + .DO(), + .DRDY(), + .LOCKED(pll1_lckd), + .CLKFBIN(buf_pll1_fb_out), + .CLKIN1(clkdiv), + .CLKIN2(1'b0), + .CLKINSEL(1'b1), + .DADDR(5'b00000), + .DCLK(1'b0), + .DEN(1'b0), + .DI(16'h0000), + .DWE(1'b0), + .RST(1'b0), + .REL(1'b0) +); + +BUFPLL #( + .DIVIDE(4) +) wr_bufpll_left ( + .PLLIN(pll1out0), + .GCLK(sys_clk), + .LOCKED(pll1_lckd), + .IOCLK(clk4x_wr_left), + .LOCK(), + .SERDESSTROBE(clk4x_wr_strb_left) +); + +BUFPLL #( + .DIVIDE(4) +) wr_bufpll_right ( + .PLLIN(pll1out1), + .GCLK(sys_clk), + .LOCKED(pll1_lckd), + .IOCLK(clk4x_wr_right), + .LOCK(), + .SERDESSTROBE(clk4x_wr_strb_right) +); + +BUFG bufg_x1( + .I(pll1out2), + .O(sys_clk) +); + +BUFG bufg_x2_2( + .I(pll1out3), + .O(clk2x_90) +); + +/* + * Generate clk4x_rd. This clock is sourced from clk2x_90. + * An IODELAY2 element is included in the path of this clock so that + * any variation in IDELAY element's base delay is compensated when this clock + * is used to capture read data which also goes through IDELAY element. + */ + +wire rd_clk_out; + +ODDR2 #( + .DDR_ALIGNMENT("C0"), + .INIT(1'b0), + .SRTYPE("ASYNC") +) rd_clk_out_inst ( + .Q(rd_clk_out), + .C0(clk2x_90), + .C1(~clk2x_90), + .CE(1'b1), + .D0(1'b1), + .D1(1'b0), + .R(1'b0), + .S(1'b0) +); + +wire rd_clk_out_oe_n; + +ODDR2 #( + .DDR_ALIGNMENT("C0"), + .INIT(1'b0), + .SRTYPE("ASYNC") +) rd_clk_out_oe_inst ( + .Q(rd_clk_out_oe_n), + .C0(clk2x_90), + .C1(~clk2x_90), + .CE(1'b1), + .D0(1'b0), + .D1(1'b0), + .R(1'b0), + .S(1'b0) +); + +wire rd_clk_fb; + +/* Dummy pin used for calibration */ +IOBUF rd_clk_loop_back_inst( + .O(rd_clk_fb), + .IO(rd_clk_lb), + .I(rd_clk_out), + .T(rd_clk_out_oe_n) +); + +wire rd_clk_fb_dly; + +IODELAY2 #( + .DATA_RATE("DDR"), + .IDELAY_VALUE(0), + .IDELAY2_VALUE(0), + .IDELAY_MODE("NORMAL"), + .ODELAY_VALUE(0), + .IDELAY_TYPE("FIXED"), + .COUNTER_WRAPAROUND("STAY_AT_LIMIT"), + .DELAY_SRC("IDATAIN"), + .SERDES_MODE("NONE"), + .SIM_TAPDELAY_VALUE(49) +) iodelay_cm ( + .IDATAIN(rd_clk_fb), + .TOUT(), + .DOUT(), + .T(1'b1), + .ODATAIN(1'b0), + .DATAOUT(rd_clk_fb_dly), + .DATAOUT2(), + .IOCLK0(1'b0), + .IOCLK1(1'b0), + .CLK(1'b0), + .CAL(1'b0), + .INC(1'b0), + .CE(1'b0), + .RST(1'b0), + .BUSY() +); + +wire rd_clk_fb_dly_bufio; + +BUFIO2 #( + .DIVIDE(1), + .DIVIDE_BYPASS("FALSE"), + .I_INVERT("FALSE") +) bufio2_inst ( + .I(rd_clk_fb_dly), + .IOCLK(), + .DIVCLK(rd_clk_fb_dly_bufio), + .SERDESSTROBE() +); + +wire pll2_lckd; +wire buf_pll2_fb_out; +wire pll2out0; +wire pll2out1; + +PLL_ADV #( + .BANDWIDTH("OPTIMIZED"), + .CLKFBOUT_MULT(4), + .CLKFBOUT_PHASE(0.0), + .CLKIN1_PERIOD(clk2x_period), + .CLKIN2_PERIOD(clk2x_period), + .CLKOUT0_DIVIDE(2), + .CLKOUT0_DUTY_CYCLE(0.5), + .CLKOUT0_PHASE(0.0), + .CLKOUT1_DIVIDE(2), + .CLKOUT1_DUTY_CYCLE(0.5), + .CLKOUT1_PHASE(0.0), + .CLKOUT2_DIVIDE(7), + .CLKOUT2_DUTY_CYCLE(0.5), + .CLKOUT2_PHASE(0.0), + .CLKOUT3_DIVIDE(7), + .CLKOUT3_DUTY_CYCLE(0.5), + .CLKOUT3_PHASE(0.0), + .CLKOUT4_DIVIDE(7), + .CLKOUT4_DUTY_CYCLE(0.5), + .CLKOUT4_PHASE(0.0), + .CLKOUT5_DIVIDE(7), + .CLKOUT5_DUTY_CYCLE (0.5), + .CLKOUT5_PHASE(0.0), + .COMPENSATION("INTERNAL"), + .DIVCLK_DIVIDE(1), + .REF_JITTER(0.100), + .CLK_FEEDBACK("CLKFBOUT"), + .SIM_DEVICE("SPARTAN6") +) pll2 ( + .CLKFBDCM(), + .CLKFBOUT(buf_pll2_fb_out), + .CLKOUT0(pll2out0), /* < x4 clock to capture read data */ + .CLKOUT1(pll2out1), /* < x4 clock to capture read data */ + .CLKOUT2(), + .CLKOUT3(), + .CLKOUT4(), + .CLKOUT5(), + .CLKOUTDCM0(), + .CLKOUTDCM1(), + .CLKOUTDCM2(), + .CLKOUTDCM3(), + .CLKOUTDCM4(), + .CLKOUTDCM5(), + .DO(), + .DRDY(), + .LOCKED(pll2_lckd), + .CLKFBIN(buf_pll2_fb_out), + .CLKIN1(rd_clk_fb_dly_bufio), + .CLKIN2(1'b0), + .CLKINSEL(1'b1), + .DADDR(5'b00000), + .DCLK(1'b0), + .DEN(1'b0), + .DI(16'h0000), + .DWE(1'b0), + .RST(~pll1_lckd), + .REL(1'b0) +); + +BUFPLL #( + .DIVIDE(4) +) rd_bufpll_left ( + .PLLIN(pll2out0), + .GCLK(sys_clk), + .LOCKED(pll2_lckd), + .IOCLK(clk4x_rd_left), + .LOCK(), + .SERDESSTROBE(clk4x_rd_strb_left) +); + +BUFPLL #( + .DIVIDE(4) +) rd_bufpll_right ( + .PLLIN(pll2out1), + .GCLK(sys_clk), + .LOCKED(pll2_lckd), + .IOCLK(clk4x_rd_right), + .LOCK(), + .SERDESSTROBE(clk4x_rd_strb_right) +); + +wire sdram_sys_clk_lock_d16; +reg sdram_sys_clk_lock_d17; + +/* + * Async reset generation + * The reset is de-asserted 16 clocks after both internal clocks are locked. + */ + +SRL16 reset_delay_sr( + .CLK(sys_clk), + .D(pll1_lckd & pll2_lckd), + .A0(1'b1), + .A1(1'b1), + .A2(1'b1), + .A3(1'b1), + .Q(sdram_sys_clk_lock_d16) +); + +always @(posedge sys_clk) + sdram_sys_clk_lock_d17 <= sdram_sys_clk_lock_d16; + +assign reset_n = sdram_sys_clk_lock_d17; + +endmodule diff --git a/verilog/m1reset/m1reset.v b/verilog/m1reset/m1reset.v deleted file mode 100644 index 4095e461..00000000 --- a/verilog/m1reset/m1reset.v +++ /dev/null @@ -1,62 +0,0 @@ -/* - * Milkymist-NG SoC - * Copyright (C) 2007, 2008, 2009, 2010, 2011 Sebastien Bourdeauducq - * - * This program is free software: you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation, version 3 of the License. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see . - */ - -module m1reset( - input sys_clk, - input trigger_reset, - - output reg sys_rst, - output ac97_rst_n, - output videoin_rst_n, - output flash_rst_n -); - -reg [19:0] rst_debounce; -initial rst_debounce <= 20'hFFFFF; -initial sys_rst <= 1'b1; -always @(posedge sys_clk) begin - if(trigger_reset) - rst_debounce <= 20'hFFFFF; - else if(rst_debounce != 20'd0) - rst_debounce <= rst_debounce - 20'd1; - sys_rst <= rst_debounce != 20'd0; -end - -assign ac97_rst_n = ~sys_rst; -assign videoin_rst_n = ~sys_rst; - -/* - * We must release the Flash reset before the system reset - * because the Flash needs some time to come out of reset - * and the CPU begins fetching instructions from it - * as soon as the system reset is released. - * From datasheet, minimum reset pulse width is 100ns - * and reset-to-read time is 150ns. - */ - -reg [7:0] flash_rstcounter; -initial flash_rstcounter <= 8'd0; -always @(posedge sys_clk) begin - if(trigger_reset) - flash_rstcounter <= 8'd0; - else if(~flash_rstcounter[7]) - flash_rstcounter <= flash_rstcounter + 8'd1; -end - -assign flash_rst_n = flash_rstcounter[7]; - -endmodule