#
# This file is part of LiteX-Boards.
#
# Copyright (c) 2020 Antmicro <www.antmicro.com>
# SPDX-License-Identifier: BSD-2-Clause

from litex.build.generic_platform import *
from litex.build.xilinx import XilinxUSPPlatform, VivadoProgrammer

# IOs ----------------------------------------------------------------------------------------------

_io = [
    # Clk / Rst
    ("clk100", 0,
        Subsignal("n", Pins("AD4"), IOStandard("DIFF_SSTL12_DCI")),
        Subsignal("p", Pins("AD5"), IOStandard("DIFF_SSTL12_DCI")),
    ),
    ("clk100_gtr", 0,
        Subsignal("p", Pins("C21"), IOStandard("DIFF_SSTL12")),
        Subsignal("n", Pins("C22"), IOStandard("DIFF_SSTL12")),
    ),
    ("clk27_gtr", 0,
        Subsignal("p", Pins("A21"), IOStandard("DIFF_SSTL12")),
        Subsignal("n", Pins("A22"), IOStandard("DIFF_SSTL12")),
    ),
    ("clk33", 0, Pins("AD4"), IOStandard("SSTL12")),
    ("cpu_reset", 0, Pins("N19"), IOStandard("LVCMOS33")),

    # Leds
    ("user_led", 0, Pins("H2"),   IOStandard("LVCMOS18")),
    ("user_led", 1, Pins("P9"),   IOStandard("LVCMOS18")),
    ("user_led", 2, Pins("K5"),   IOStandard("LVCMOS18")),

    # Serial
    ("serial", 0,
        Subsignal("rx", Pins("AA10")),  # Module connector A: A60 (Meccury PE1: "IO B" connector 32)
        Subsignal("tx", Pins("AA11")),  # Module connector A: A58 (Meccury PE1: "IO B" connector 31)
        IOStandard("LVCMOS33"),
    ),

    # I2C
    ("i2c", 0,
        Subsignal("scl", Pins("D12")),
        Subsignal("sda", Pins("C12")),
        IOStandard("LVCMOS18")
    ),

    # DDR4 SDRAM
    ("ddram", 0,
        Subsignal("a",       Pins(
            "AC4 AC3 AB4 AB3 AB2 AC2 AB1 AC1",
            "AB5 AG4 AH4 AG3 AH3 AE3"),       IOStandard("SSTL12_DCI")),
        Subsignal("we_n",    Pins("AF3"),     IOStandard("SSTL12_DCI")),  # A14
        Subsignal("cas_n",   Pins("AE2"),     IOStandard("SSTL12_DCI")),  # A15
        Subsignal("ras_n",   Pins("AF2"),     IOStandard("SSTL12_DCI")),  # A16
        Subsignal("ba",      Pins("AH1 AF1"), IOStandard("SSTL12_DCI")),
        Subsignal("bg",      Pins("AG1"),     IOStandard("SSTL12_DCI")),
        Subsignal("cs_n",    Pins("AH9"),     IOStandard("SSTL12_DCI")),
        Subsignal("act_n",   Pins("AH2"),     IOStandard("SSTL12_DCI")),
        Subsignal("dm",      Pins("AC9 AG9"), IOStandard("POD12_DCI")),
        Subsignal("dq",      Pins(
            "AB6 AC6 AE9 AE8 AB8 AC8 AB7 AC7",
            "AE5 AF5 AF8 AG8 AH8 AH7 AF7 AF6"), IOStandard("POD12_DCI"),
            Misc("PRE_EMPHASIS=RDRV_240"),
            Misc("EQUALIZATION=EQ_LEVEL2")),
        Subsignal("dqs_p",   Pins("AD7 AG6"), IOStandard("DIFF_POD12_DCI"),
            Misc("PRE_EMPHASIS=RDRV_240"),
            Misc("EQUALIZATION=EQ_LEVEL2")),
        Subsignal("dqs_n",   Pins("AE7 AG5"), IOStandard("DIFF_POD12_DCI"),
            Misc("PRE_EMPHASIS=RDRV_240"),
            Misc("EQUALIZATION=EQ_LEVEL2")),
        Subsignal("clk_p",   Pins("AD2"), IOStandard("DIFF_SSTL12_DCI")),
        Subsignal("clk_n",   Pins("AD1"), IOStandard("DIFF_SSTL12_DCI")),
        Subsignal("cke",     Pins("AH6"), IOStandard("SSTL12_DCI")),
        Subsignal("odt",     Pins("AE4"), IOStandard("SSTL12_DCI")),
        Subsignal("reset_n", Pins("G4"),  IOStandard("LVCMOS18")),
        Misc("SLEW=FAST"),
    ),
]

# Connectors ---------------------------------------------------------------------------------------

_connectors = []

# Platform -----------------------------------------------------------------------------------------

class Platform(XilinxUSPPlatform):
    default_clk_name   = "clk100"
    default_clk_period = 1e9/100e6

    def __init__(self, toolchain="vivado"):
        XilinxUSPPlatform.__init__(self, "xczu2eg-sfvc784-1-i", _io, _connectors, toolchain=toolchain)

    def create_programmer(self):
        return VivadoProgrammer()

    def do_finalize(self, fragment):
        XilinxUSPPlatform.do_finalize(self, fragment)
        self.add_period_constraint(self.lookup_request("clk100",     loose=True), 1e9/100e6)
        self.add_period_constraint(self.lookup_request("clk100_gtr", loose=True), 1e9/100e6)
        self.add_period_constraint(self.lookup_request("clk27_gtr",  loose=True), 1e9/27e6)
        self.add_period_constraint(self.lookup_request("clk33",      loose=True), 1e9/33e6)
        self.add_platform_command("set_property BITSTREAM.CONFIG.OVERTEMPSHUTDOWN ENABLE [current_design]")
        self.add_platform_command("set_property BITSTREAM.CONFIG.UNUSEDPIN PULLNONE [current_design]")
        self.add_platform_command("set_property INTERNAL_VREF 0.84 [get_iobanks 64]")