linsn_rv901t.py

#!/usr/bin/env python3

# This file is Copyright (c) 2019-2020 Florent Kermarrec <florent@enjoy-digital.fr>
# License: BSD

import argparse

from migen import *

from litex_boards.platforms import linsn_rv901t

from litex.soc.integration.soc_sdram import *
from litex.soc.integration.builder import *
from litex.soc.cores.clock import S6PLL

from litedram.modules import M12L64322A
from litedram.phy import GENSDRPHY

from liteeth.phy.s6rgmii import LiteEthPHYRGMII
from liteeth.mac import LiteEthMAC

# CRG ----------------------------------------------------------------------------------------------

class _CRG(Module):
    def __init__(self, platform, sys_clk_freq):
        self.clock_domains.cd_sys    = ClockDomain()
        self.clock_domains.cd_sys_ps = ClockDomain(reset_less=True)

        # # #

        clk25 = platform.request("clk25")
        platform.add_period_constraint(clk25, 1e9/25e6)

        self.submodules.pll = pll = S6PLL(speedgrade=-2)
        pll.register_clkin(clk25, 25e6)
        pll.create_clkout(self.cd_sys,    sys_clk_freq)
        pll.create_clkout(self.cd_sys_ps, sys_clk_freq, phase=270)

        self.specials += Instance("ODDR2",
            p_DDR_ALIGNMENT="NONE",
            p_INIT=0, p_SRTYPE="SYNC",
            i_D0=0, i_D1=1, i_S=0, i_R=0, i_CE=1,
            i_C0=self.cd_sys.clk, i_C1=~self.cd_sys.clk,
            o_Q=platform.request("sdram_clock"))

# BaseSoC ------------------------------------------------------------------------------------------

class BaseSoC(SoCSDRAM):
    def __init__(self, **kwargs):
        platform     = linsn_rv901t.Platform()
        sys_clk_freq = int(75e6)

        # SoCSDRAM ---------------------------------------------------------------------------------
        SoCSDRAM.__init__(self, platform, clk_freq=sys_clk_freq, **kwargs)

        # CRG --------------------------------------------------------------------------------------
        self.submodules.crg = _CRG(platform, sys_clk_freq)

        # SDR SDRAM --------------------------------------------------------------------------------
        self.submodules.sdrphy = GENSDRPHY(platform.request("sdram"))
        sdram_module = M12L64322A(sys_clk_freq, "1:1")
        self.register_sdram(self.sdrphy, sdram_module.geom_settings, sdram_module.timing_settings)

# EthernetSoC --------------------------------------------------------------------------------------

class EthernetSoC(BaseSoC):
    mem_map = {
        "ethmac": 0xb0000000,
    }
    mem_map.update(BaseSoC.mem_map)

    def __init__(self, eth_phy=0, **kwargs):
        BaseSoC.__init__(self, **kwargs)

        # Ethernet ---------------------------------------------------------------------------------
        # phy
        self.submodules.ethphy = LiteEthPHYRGMII(
            clock_pads = self.platform.request("eth_clocks", eth_phy),
            pads       = self.platform.request("eth", eth_phy))
        self.add_csr("ethphy")
        # mac
        self.submodules.ethmac = LiteEthMAC(
            phy        = self.ethphy,
            dw         = 32,
            interface  = "wishbone",
            endianness = self.cpu.endianness)
        self.add_memory_region("ethmac", self.mem_map["ethmac"], 0x2000, type="io")
        self.add_wb_slave(self.mem_map["ethmac"], self.ethmac.bus, 0x2000)
        self.add_csr("ethmac")
        self.add_interrupt("ethmac")
        # timing constraints
        self.platform.add_period_constraint(self.ethphy.crg.cd_eth_rx.clk, 1e9/125e6)
        self.platform.add_period_constraint(self.ethphy.crg.cd_eth_tx.clk, 1e9/125e6)
        self.platform.add_false_path_constraints(
            self.crg.cd_sys.clk,
            self.ethphy.crg.cd_eth_rx.clk,
            self.ethphy.crg.cd_eth_tx.clk)

# Build --------------------------------------------------------------------------------------------

def main():
    parser = argparse.ArgumentParser(description="LiteX SoC on Linsn RV901T")
    builder_args(parser)
    soc_sdram_args(parser)
    parser.add_argument("--with-ethernet", action="store_true", help="enable Ethernet support")
    parser.add_argument("--eth-phy", default=0, type=int, help="Ethernet PHY 0 or 1 (default=0)")
    args = parser.parse_args()

    if args.with_ethernet:
        soc = EthernetSoC(eth_phy=args.eth_phy, **soc_sdram_argdict(args))
    else:
        soc = BaseSoC(**soc_sdram_argdict(args))
    builder = Builder(soc, **builder_argdict(args))
    builder.build()


if __name__ == "__main__":
    main()