artiq/artiq/gateware/targets/sayma_rtm.py

#!/usr/bin/env python3

import os

from migen import *
from migen.genlib.resetsync import AsyncResetSynchronizer
from migen.build.platforms.sinara import sayma_rtm

from misoc.interconnect import wishbone, stream
from misoc.interconnect.csr import *
from misoc.cores import spi
from misoc.integration.wb_slaves import WishboneSlaveManager
from misoc.integration.cpu_interface import get_csr_csv

from artiq.gateware import serwb


class CRG(Module):
    def __init__(self, platform):
        self.clock_domains.cd_sys = ClockDomain()
        self.clock_domains.cd_clk200 = ClockDomain()

        clk50 = platform.request("clk50")
        self.reset = Signal()

        pll_locked = Signal()
        pll_fb = Signal()
        pll_sys = Signal()
        pll_clk200 = Signal()
        self.specials += [
            Instance("PLLE2_BASE",
                     p_STARTUP_WAIT="FALSE", o_LOCKED=pll_locked,

                     # VCO @ 1GHz
                     p_REF_JITTER1=0.01, p_CLKIN1_PERIOD=20.0,
                     p_CLKFBOUT_MULT=20, p_DIVCLK_DIVIDE=1,
                     i_CLKIN1=clk50, i_CLKFBIN=pll_fb, o_CLKFBOUT=pll_fb,

                     # 125MHz
                     p_CLKOUT0_DIVIDE=8, p_CLKOUT0_PHASE=0.0, o_CLKOUT0=pll_sys,

                     # 200MHz
                     p_CLKOUT3_DIVIDE=5, p_CLKOUT3_PHASE=0.0, o_CLKOUT3=pll_clk200
            ),
            Instance("BUFG", i_I=pll_sys, o_O=self.cd_sys.clk),
            Instance("BUFG", i_I=pll_clk200, o_O=self.cd_clk200.clk),
            AsyncResetSynchronizer(self.cd_sys, ~pll_locked | self.reset),
            AsyncResetSynchronizer(self.cd_clk200, ~pll_locked | self.reset)
        ]

        reset_counter = Signal(4, reset=15)
        ic_reset = Signal(reset=1)
        self.sync.clk200 += \
            If(reset_counter != 0,
                reset_counter.eq(reset_counter - 1)
            ).Else(
                ic_reset.eq(0)
            )
        self.specials += Instance("IDELAYCTRL", i_REFCLK=ClockSignal("clk200"), i_RST=ic_reset)


class RTMIdentifier(Module, AutoCSR):
    def __init__(self):
        self.identifier = CSRStatus(32)
        self.comb += self.identifier.status.eq(0x5352544d)  # "SRTM"


CSR_RANGE_SIZE = 0x800


class SaymaRTM(Module):

    def __init__(self, platform):
        csr_devices = []

        self.submodules.crg = CRG(platform)
        self.crg.cd_sys.clk.attr.add("keep")
        clk_freq = 125e6
        platform.add_period_constraint(self.crg.cd_sys.clk, 8.0)

        self.submodules.rtm_identifier = RTMIdentifier()
        csr_devices.append("rtm_identifier")

        self.submodules.converter_spi = spi.SPIMaster(platform.request("hmc_spi"))
        csr_devices.append("converter_spi")
        self.comb += platform.request("hmc7043_reset").eq(0)

        # TODO: push all those serwb bits into library modules
        # maybe keep only 3 user-visible modules: serwb PLL, serwb PHY, and serwb core
        # TODO: after this is done, stop exposing internal modules in serwb/__init__.py
        # TODO: avoid having a "serdes" clock domain at the top level, rename to "serwb_serdes" or similar.
        # TODO: the above also applies to sayma_amc_standalone.py.

        # serwb SERDES
        serwb_pll = serwb.s7phy.S7SerdesPLL(125e6, 1.25e9, vco_div=1)
        self.submodules += serwb_pll

        serwb_serdes = serwb.s7phy.S7Serdes(serwb_pll, platform.request("amc_rtm_serwb"), mode="slave")
        self.submodules += serwb_serdes
        serwb_init = serwb.phy.SerdesSlaveInit(serwb_serdes, taps=32)
        self.submodules += serwb_init
        self.comb += self.crg.reset.eq(serwb_init.reset)

        serwb_serdes.cd_serdes.clk.attr.add("keep")
        serwb_serdes.cd_serdes_20x.clk.attr.add("keep")
        serwb_serdes.cd_serdes_5x.clk.attr.add("keep")
        platform.add_period_constraint(serwb_serdes.cd_serdes.clk, 32.0),
        platform.add_period_constraint(serwb_serdes.cd_serdes_20x.clk, 1.6),
        platform.add_period_constraint(serwb_serdes.cd_serdes_5x.clk, 6.4)
        platform.add_false_path_constraints(
            self.crg.cd_sys.clk,
            serwb_serdes.cd_serdes.clk,
            serwb_serdes.cd_serdes_5x.clk)

        # serwb master
        serwb_depacketizer = serwb.packet.Depacketizer(int(clk_freq))
        serwb_packetizer = serwb.packet.Packetizer()
        self.submodules += serwb_depacketizer, serwb_packetizer
        serwb_etherbone = serwb.etherbone.Etherbone(mode="master")
        self.submodules += serwb_etherbone
        serwb_tx_cdc = ClockDomainsRenamer({"write": "sys", "read": "serdes"})(
            stream.AsyncFIFO([("data", 32)], 8))
        self.submodules += serwb_tx_cdc
        serwb_rx_cdc = ClockDomainsRenamer({"write": "serdes", "read": "sys"})(
            stream.AsyncFIFO([("data", 32)], 8))
        self.submodules += serwb_rx_cdc
        self.comb += [
            # core <--> etherbone
            serwb_depacketizer.source.connect(serwb_etherbone.sink),
            serwb_etherbone.source.connect(serwb_packetizer.sink),

            # core --> serdes
            serwb_packetizer.source.connect(serwb_tx_cdc.sink),
            If(serwb_tx_cdc.source.stb & serwb_init.ready,
                serwb_serdes.tx_data.eq(serwb_tx_cdc.source.data)
            ),
            serwb_tx_cdc.source.ack.eq(serwb_init.ready),

            # serdes --> core
            serwb_rx_cdc.sink.stb.eq(serwb_init.ready),
            serwb_rx_cdc.sink.data.eq(serwb_serdes.rx_data),
            serwb_rx_cdc.source.connect(serwb_depacketizer.sink),
        ]

        # process CSR devices and connect them to serwb
        self.csr_regions = []
        wb_slaves = WishboneSlaveManager(0x10000000)
        for i, name in enumerate(csr_devices):
            origin = i*CSR_RANGE_SIZE
            module = getattr(self, name)
            csrs = module.get_csrs()

            bank = wishbone.CSRBank(csrs)
            self.submodules += bank

            wb_slaves.add(origin, CSR_RANGE_SIZE, bank.bus)
            self.csr_regions.append((name, origin, 32, csrs))

        self.submodules += wishbone.Decoder(serwb_etherbone.wishbone.bus,
                                            wb_slaves.get_interconnect_slaves(),
                                            register=True)


def main():
    build_dir = "artiq_sayma_rtm"
    platform = sayma_rtm.Platform()
    top = SaymaRTM(platform)
    with open(os.path.join(build_dir, "sayma_rtm_csr.csv"), "w") as f:
        f.write(get_csr_csv(top.csr_regions))
    platform.build(top, build_dir=build_dir)


if __name__ == "__main__":
    main()