#!/usr/bin/env python3

#
# This file is part of LiteX-Boards.
#
# Copyright (c) 2018-2019 Florent Kermarrec <florent@enjoy-digital.fr>
# SPDX-License-Identifier: BSD-2-Clause

from migen import *

from litex.gen import LiteXModule

from litex_boards.platforms import digilent_nexys4ddr

from litex.soc.cores.clock import *
from litex.soc.integration.soc import SoCRegion
from litex.soc.integration.soc_core import *
from litex.soc.integration.builder import *
from litex.soc.cores.video import VideoVGAPHY
from litex.soc.cores.led import LedChaser

from litedram.modules import MT47H64M16
from litedram.phy import s7ddrphy

from liteeth.phy.rmii import LiteEthPHYRMII

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

class _CRG(LiteXModule):
    def __init__(self, platform, sys_clk_freq):
        self.rst          = Signal()
        self.cd_sys       = ClockDomain()
        self.cd_sys2x     = ClockDomain()
        self.cd_sys2x_dqs = ClockDomain()
        self.cd_idelay    = ClockDomain()
        self.cd_eth       = ClockDomain()
        self.cd_vga       = ClockDomain()
        # # #

        self.pll = pll = S7MMCM(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_sys2x,     2*sys_clk_freq)
        pll.create_clkout(self.cd_sys2x_dqs, 2*sys_clk_freq, phase=90)
        pll.create_clkout(self.cd_idelay,    200e6)
        pll.create_clkout(self.cd_eth,       50e6)
        pll.create_clkout(self.cd_vga,       40e6)
        platform.add_false_path_constraints(self.cd_sys.clk, pll.clkin) # Ignore sys_clk to pll.clkin path created by SoC's rst.

        self.idelayctrl = S7IDELAYCTRL(self.cd_idelay)

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

class BaseSoC(SoCCore):
    def __init__(self, sys_clk_freq=75e6, with_ethernet=False, with_etherbone=False,
                 with_led_chaser=True, with_video_terminal=False, with_video_framebuffer=False,
                 **kwargs):
        platform = digilent_nexys4ddr.Platform()

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

        # SoCCore ----------------------------------_-----------------------------------------------
        SoCCore.__init__(self, platform, sys_clk_freq, ident="LiteX SoC on Nexys4DDR", **kwargs)

        # DDR2 SDRAM -------------------------------------------------------------------------------
        if not self.integrated_main_ram_size:
            self.ddrphy = s7ddrphy.A7DDRPHY(platform.request("ddram"),
                memtype      = "DDR2",
                nphases      = 2,
                sys_clk_freq = sys_clk_freq)
            self.add_sdram("sdram",
                phy           = self.ddrphy,
                module        = MT47H64M16(sys_clk_freq, "1:2"),
                l2_cache_size = kwargs.get("l2_size", 8192)
            )

        # Ethernet / Etherbone ---------------------------------------------------------------------
        if with_ethernet or with_etherbone:
            self.ethphy = LiteEthPHYRMII(
                clock_pads = self.platform.request("eth_clocks"),
                pads       = self.platform.request("eth"))
            if with_ethernet:
                self.add_ethernet(phy=self.ethphy)
            if with_etherbone:
                self.add_etherbone(phy=self.ethphy)

        # Video ------------------------------------------------------------------------------------
        if with_video_terminal or with_video_framebuffer:
            self.videophy = VideoVGAPHY(platform.request("vga"), clock_domain="vga")
            if with_video_terminal:
                self.add_video_terminal(phy=self.videophy, timings="800x600@60Hz", clock_domain="vga")
            if with_video_framebuffer:
                self.add_video_framebuffer(phy=self.videophy, timings="800x600@60Hz", clock_domain="vga")

        # Leds -------------------------------------------------------------------------------------
        if with_led_chaser:
            self.leds = LedChaser(
                pads         = platform.request_all("user_led"),
                sys_clk_freq = sys_clk_freq)

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

def main():
    from litex.build.parser import LiteXArgumentParser
    parser = LiteXArgumentParser(platform=digilent_nexys4ddr.Platform, description="LiteX SoC on Nexys4DDR.")
    parser.add_target_argument("--sys-clk-freq", default=75e6, type=float, help="System clock frequency.")
    ethopts = parser.target_group.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.target_group.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.target_group.add_mutually_exclusive_group()
    viopts.add_argument("--with-video-terminal",    action="store_true", help="Enable Video Terminal (VGA).")
    viopts.add_argument("--with-video-framebuffer", action="store_true", help="Enable Video Framebuffer (VGA).")
    args = parser.parse_args()

    soc = BaseSoC(
        sys_clk_freq           = args.sys_clk_freq,
        with_ethernet          = args.with_ethernet,
        with_etherbone         = args.with_etherbone,
        with_video_terminal    = args.with_video_terminal,
        with_video_framebuffer = args.with_video_framebuffer,
        **parser.soc_argdict
    )
    if args.with_spi_sdcard:
        soc.add_spi_sdcard()
    if args.with_sdcard:
        soc.add_sdcard()
    builder = Builder(soc, **parser.builder_argdict)
    if args.build:
        builder.build(**parser.toolchain_argdict)

    if args.load:
        prog = soc.platform.create_programmer()
        prog.load_bitstream(builder.get_bitstream_filename(mode="sram"))

if __name__ == "__main__":
    main()