mimas_a7.py

#!/usr/bin/env python3

#
# This file is part of LiteX-Boards.
#
# Copyright (c) 2018-2019 Rohit Singh <rohit@rohitksingh.in>
# Copyright (c) 2020 Feliks Montez <feliks.montez@gmail.com>
# SPDX-License-Identifier: BSD-2-Clause

import os
import argparse

from migen import *

from litex_boards.platforms import mimas_a7
from litex.build.xilinx.vivado import vivado_build_args, vivado_build_argdict

from litex.soc.cores.clock import *
from litex.soc.integration.soc_core import *
from litex.soc.integration.soc_sdram import *
from litex.soc.integration.builder import *
from litex.soc.cores.led import LedChaser

from litedram.modules import MT41J128M16
from litedram.phy import s7ddrphy

from liteeth.phy.s7rgmii import LiteEthPHYRGMII

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

class _CRG(Module):
    def __init__(self, platform, sys_clk_freq):
        self.rst = Signal()
        self.clock_domains.cd_sys       = ClockDomain()
        self.clock_domains.cd_sys4x     = ClockDomain(reset_less=True)
        self.clock_domains.cd_sys4x_dqs = ClockDomain(reset_less=True)
        self.clock_domains.cd_idelay    = ClockDomain()

        # # #

        self.submodules.pll = pll = S7PLL(speedgrade=-1)
        self.comb += pll.reset.eq(platform.request("cpu_reset") | self.rst)
        pll.register_clkin(platform.request("clk100"), 100e6)
        pll.create_clkout(self.cd_sys,       sys_clk_freq)
        pll.create_clkout(self.cd_sys4x,     4*sys_clk_freq)
        pll.create_clkout(self.cd_sys4x_dqs, 4*sys_clk_freq, phase=90)
        pll.create_clkout(self.cd_idelay,    200e6)
        platform.add_false_path_constraints(self.cd_sys.clk, pll.clkin) # Ignore sys_clk to pll.clkin path created by SoC's rst.

        self.submodules.idelayctrl = S7IDELAYCTRL(self.cd_idelay)

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

class BaseSoC(SoCCore):
    def __init__(self, sys_clk_freq=int(100e6), with_ethernet=False, **kwargs):
        platform = mimas_a7.Platform()

        # SoCCore ----------------------------------------------------------------------------------
        SoCCore.__init__(self, platform, sys_clk_freq,
            ident          = "LiteX SoC on Mimas A7",
            ident_version  = True,
            **kwargs)

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

        # DDR3 SDRAM -------------------------------------------------------------------------------
        if not self.integrated_main_ram_size:
            self.submodules.ddrphy = s7ddrphy.A7DDRPHY(platform.request("ddram"),
                memtype      = "DDR3",
                nphases      = 4,
                sys_clk_freq = sys_clk_freq)
            self.add_csr("ddrphy")
            self.add_sdram("sdram",
                phy                     = self.ddrphy,
                module                  = MT41J128M16(sys_clk_freq, "1:4"),
                origin                  = self.mem_map["main_ram"],
                size                    = kwargs.get("max_sdram_size", 0x40000000),
                l2_cache_size           = kwargs.get("l2_size", 8192),
                l2_cache_min_data_width = kwargs.get("min_l2_data_width", 128),
                l2_cache_reverse        = True
            )

        # Ethernet ---------------------------------------------------------------------------------
        if with_ethernet:
            self.submodules.ethphy = LiteEthPHYRGMII(
                clock_pads = self.platform.request("eth_clocks"),
                pads       = self.platform.request("eth"))
            self.add_csr("ethphy")
            self.add_ethernet(phy=self.ethphy)

        # Leds -------------------------------------------------------------------------------------
        self.submodules.leds = LedChaser(
            pads         = platform.request_all("user_led"),
            sys_clk_freq = sys_clk_freq)
        self.add_csr("leds")

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

def main():
    parser = argparse.ArgumentParser(description="LiteX SoC on Mimas A7")
    parser.add_argument("--build",         action="store_true", help="Build bitstream")
    parser.add_argument("--load",          action="store_true", help="Load bitstream")
    parser.add_argument("--sys-clk-freq",  default=100e6,       help="System clock frequency (default: 100MHz)")
    parser.add_argument("--with-ethernet", action="store_true", help="Enable Ethernet support")
    builder_args(parser)
    soc_sdram_args(parser)
    vivado_build_args(parser)
    args = parser.parse_args()

    soc = BaseSoC(
        sys_clk_freq  = int(float(args.sys_clk_freq)),
        with_ethernet = args.with_ethernet,
        **soc_sdram_argdict(args)
    )
    builder = Builder(soc, **builder_argdict(args))
    builder.build(**vivado_build_argdict(args), run=args.build)

    if args.load:
        prog = soc.platform.create_programmer()
        prog.load_bitstream(os.path.join(builder.gateware_dir, soc.build_name + ".bit"))

if __name__ == "__main__":
    main()