litex-boards/litex_boards/platforms/tinyfpga_bx.py

#
# This file is part of LiteX-Boards.
#
# Copyright (c) 2018 William D. Jones <thor0505@comcast.net>
# Copyright (c) 2019 Florent Kermarrec <florent@enjoy-digital.fr>
# SPDX-License-Identifier: BSD-2-Clause

from litex.build.generic_platform import *
from litex.build.lattice import LatticeiCE40Platform
from litex.build.lattice.programmer import TinyProgProgrammer

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

_io = [
    # Clk / Rst
    ("clk16", 0, Pins("B2"), IOStandard("LVCMOS33")),

    # Leds
    ("user_led", 0, Pins("B3"), IOStandard("LVCMOS33")),

    # USB
    ("usb", 0,
        Subsignal("d_p", Pins("B4")),
        Subsignal("d_n", Pins("A4")),
        Subsignal("pullup", Pins("A3")),
        IOStandard("LVCMOS33")
    ),

    # SPIFlash
    ("spiflash", 0,
        Subsignal("cs_n", Pins("F7"), IOStandard("LVCMOS33")),
        Subsignal("clk",  Pins("G7"), IOStandard("LVCMOS33")),
        Subsignal("mosi", Pins("G6"), IOStandard("LVCMOS33")),
        Subsignal("miso", Pins("H7"), IOStandard("LVCMOS33")),
        Subsignal("wp",   Pins("H4"), IOStandard("LVCMOS33")),
        Subsignal("hold", Pins("J8"), IOStandard("LVCMOS33"))
    ),
    ("spiflash4x", 0,
        Subsignal("cs_n", Pins("F7"), IOStandard("LVCMOS33")),
        Subsignal("clk",  Pins("G7"), IOStandard("LVCMOS33")),
        Subsignal("dq",   Pins("G6 H7 H4 J8"), IOStandard("LVCMOS33"))
    ),
]

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

_connectors = [
    # A2-H2, Pins 1-13
    # H9-A6, Pins 14-24
    # G1-J2, Pins 25-31
    ("GPIO",  "A2 A1 B1 C2 C1 D2 D1 E2 E1 G2 H1 J1 H2 H9 D9 D8 C9 A9 B8 A8 B7 A7 B6 A6"),
    ("EXTRA", "G1 J3 J4 G9 J9 E8 J2")
]

# Default peripherals
serial = [
    ("serial", 0,
        Subsignal("tx", Pins("GPIO:0")),
        Subsignal("rx", Pins("GPIO:1")),
        IOStandard("LVCMOS33")
    )
]

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

class Platform(LatticeiCE40Platform):
    default_clk_name   = "clk16"
    default_clk_period = 1e9/16e6

    def __init__(self, toolchain="icestorm"):
        LatticeiCE40Platform.__init__(self, "ice40-lp8k-cm81", _io, _connectors, toolchain=toolchain)
        self.add_extension(serial)

    def create_programmer(self):
        return TinyProgProgrammer()

    def do_finalize(self, fragment):
        LatticeiCE40Platform.do_finalize(self, fragment)
        self.add_period_constraint(self.lookup_request("clk16", loose=True), 1e9/16e6)