#!/usr/bin/env python3

#
# This file is part of LiteX-Boards.
#
# Copyright (c) 2021 Florent Kermarrec <florent@enjoy-digital.fr>
# SPDX-License-Identifier: BSD-2-Clause

import os
import argparse
import sys

from migen import *

from litex_boards.platforms import litex_m2_baseboard

from litex.build.lattice.trellis import trellis_args, trellis_argdict

from litex.soc.cores.clock import *
from litex.soc.integration.soc_core import *
from litex.soc.integration.builder import *
from litex.soc.cores.video import VideoHDMIPHY

from liteeth.phy.ecp5rgmii import LiteEthPHYRGMII

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

class _CRG(Module):
    def __init__(self, platform, sys_clk_freq, with_video_pll=False):
        self.rst = Signal()
        self.clock_domains.cd_por = ClockDomain(reset_less=True)
        self.clock_domains.cd_sys = ClockDomain()

        # # #

        # Clk / Rst
        clk50 = platform.request("clk50")

        # Power on reset
        por_count = Signal(16, reset=2**16-1)
        por_done  = Signal()
        self.comb += self.cd_por.clk.eq(clk50)
        self.comb += por_done.eq(por_count == 0)
        self.sync.por += If(~por_done, por_count.eq(por_count - 1))

        # PLL
        self.submodules.pll = pll = ECP5PLL()
        self.comb += pll.reset.eq(~por_done | self.rst)
        pll.register_clkin(clk50, 50e6)
        pll.create_clkout(self.cd_sys, sys_clk_freq)

        # Video PLL
        if with_video_pll:
            self.submodules.video_pll = video_pll = ECP5PLL()
            self.comb += pll.reset.eq(~por_done | self.rst)
            video_pll.register_clkin(clk50, 50e6)
            self.clock_domains.cd_hdmi   = ClockDomain()
            self.clock_domains.cd_hdmi5x = ClockDomain()
            video_pll.create_clkout(self.cd_hdmi,    25e6, margin=0)
            video_pll.create_clkout(self.cd_hdmi5x, 125e6, margin=0)

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

class BaseSoC(SoCCore):
    def __init__(self, sys_clk_freq=int(75e6),
        with_ethernet       = False,
        with_etherbone      = False,
        with_video_terminal = False,
        **kwargs):
        platform = litex_m2_baseboard.Platform(toolchain="trellis")

        # SoCCore ----------------------------------------------------------------------------------
        SoCCore.__init__(self, platform, sys_clk_freq,
            ident          = "LiteX SoC on LiteX M2 Baseboard",
            ident_version  = True,
            **kwargs)

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

        # Ethernet / Etherbone ---------------------------------------------------------------------
        if with_ethernet or with_etherbone:
            self.submodules.ethphy = LiteEthPHYRGMII(
                clock_pads = self.platform.request("eth_clocks"),
                pads       = self.platform.request("eth"),
                rx_delay   = 0e-9)
            if with_ethernet:
                self.add_ethernet(phy=self.ethphy)
            if with_etherbone:
                self.add_etherbone(phy=self.ethphy)


        # Video ------------------------------------------------------------------------------------
        if with_video_terminal:
            self.submodules.videophy = VideoHDMIPHY(platform.request("hdmi"), clock_domain="hdmi", pn_swap=["g", "b"])
            self.add_video_terminal(phy=self.videophy, timings="640x480@75Hz", clock_domain="hdmi")

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

def main():
    parser = argparse.ArgumentParser(description="LiteX SoC on LiteX M2 Baseboard")
    parser.add_argument("--build",        action="store_true", help="Build bitstream")
    parser.add_argument("--load",         action="store_true", help="Load bitstream")
    parser.add_argument("--flash",        action="store_true", help="Flash bitstream to SPI Flash")
    parser.add_argument("--sys-clk-freq", default=75e6,        help="System clock frequency (default: 75MHz)")
    ethopts = parser.add_mutually_exclusive_group()
    ethopts.add_argument("--with-ethernet",  action="store_true", help="Enable Ethernet support")
    ethopts.add_argument("--with-etherbone", action="store_true", help="Enable Etherbone support")
    sdopts = parser.add_mutually_exclusive_group()
    sdopts.add_argument("--with-spi-sdcard", action="store_true", help="Enable SPI-mode SDCard support")
    sdopts.add_argument("--with-sdcard",     action="store_true", help="Enable SDCard support")
    viopts = parser.add_mutually_exclusive_group()
    viopts.add_argument("--with-video-terminal", action="store_true", help="Enable Video Terminal (HDMI)")
    builder_args(parser)
    soc_core_args(parser)
    trellis_args(parser)
    args = parser.parse_args()

    soc = BaseSoC(
        sys_clk_freq        = int(float(args.sys_clk_freq)),
        with_ethernet       = args.with_ethernet,
        with_etherbone      = args.with_etherbone,
        with_video_terminal = args.with_video_terminal,
        **soc_core_argdict(args)
    )
    if args.with_spi_sdcard:
        soc.add_spi_sdcard()
    if args.with_sdcard:
        soc.add_sdcard()
    builder = Builder(soc, **builder_argdict(args))
    builder.build(**trellis_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 args.flash:
        prog = soc.platform.create_programmer()
        prog.flash(None, os.path.join(builder.gateware_dir, soc.build_name + ".bit"))

if __name__ == "__main__":
    main()