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add artix7 gtp (3gbps), share clock aligner with gth_ultrascale

This commit is contained in:
Florent Kermarrec 2018-01-19 12:17:54 +01:00
parent cdbf95d46a
commit d27727968c
5 changed files with 672 additions and 113 deletions

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@ -0,0 +1,114 @@
from math import ceil
from functools import reduce
from operator import add
from migen import *
from migen.genlib.cdc import MultiReg, PulseSynchronizer
# Changes the phase of the transceiver RX clock to align the comma to
# the LSBs of RXDATA, fixing the latency.
#
# This is implemented by repeatedly resetting the transceiver until it
# gives out the correct phase. Each reset gives a random phase.
#
# If Xilinx had designed the GTX transceiver correctly, RXSLIDE_MODE=PMA
# would achieve this faster and in a cleaner way. But:
# * the phase jumps are of 2 UI at every second RXSLIDE pulse, instead
# of 1 UI at every pulse. It is unclear what the latency becomes.
# * RXSLIDE_MODE=PMA cannot be used with the RX buffer bypassed.
# Those design flaws make RXSLIDE_MODE=PMA yet another broken and useless
# transceiver "feature".
#
# Warning: Xilinx transceivers are LSB first, and comma needs to be flipped
# compared to the usual 8b10b binary representation.
class BruteforceClockAligner(Module):
def __init__(self, comma, tx_clk_freq, check_period=6e-3):
self.rxdata = Signal(20)
self.restart = Signal()
self.ready = Signal()
check_max_val = ceil(check_period*tx_clk_freq)
check_counter = Signal(max=check_max_val+1)
check = Signal()
reset_check_counter = Signal()
self.sync.rtio_tx += [
check.eq(0),
If(reset_check_counter,
check_counter.eq(check_max_val)
).Else(
If(check_counter == 0,
check.eq(1),
check_counter.eq(check_max_val)
).Else(
check_counter.eq(check_counter-1)
)
)
]
checks_reset = PulseSynchronizer("rtio_tx", "rtio_rx")
self.submodules += checks_reset
comma_n = ~comma & 0b1111111111
comma_seen_rxclk = Signal()
comma_seen = Signal()
comma_seen_rxclk.attr.add("no_retiming")
self.specials += MultiReg(comma_seen_rxclk, comma_seen)
self.sync.rtio_rx += \
If(checks_reset.o,
comma_seen_rxclk.eq(0)
).Elif((self.rxdata[:10] == comma) | (self.rxdata[:10] == comma_n),
comma_seen_rxclk.eq(1)
)
error_seen_rxclk = Signal()
error_seen = Signal()
error_seen_rxclk.attr.add("no_retiming")
self.specials += MultiReg(error_seen_rxclk, error_seen)
rx1cnt = Signal(max=11)
self.sync.rtio_rx += [
rx1cnt.eq(reduce(add, [self.rxdata[i] for i in range(10)])),
If(checks_reset.o,
error_seen_rxclk.eq(0)
).Elif((rx1cnt != 4) & (rx1cnt != 5) & (rx1cnt != 6),
error_seen_rxclk.eq(1)
)
]
fsm = ClockDomainsRenamer("rtio_tx")(FSM(reset_state="WAIT_COMMA"))
self.submodules += fsm
fsm.act("WAIT_COMMA",
If(check,
# Errors are still OK at this stage, as the transceiver
# has just been reset and may output garbage data.
If(comma_seen,
NextState("WAIT_NOERROR")
).Else(
self.restart.eq(1)
),
checks_reset.i.eq(1)
)
)
fsm.act("WAIT_NOERROR",
If(check,
If(comma_seen & ~error_seen,
NextState("READY")
).Else(
self.restart.eq(1),
NextState("WAIT_COMMA")
),
checks_reset.i.eq(1)
)
)
fsm.act("READY",
reset_check_counter.eq(1),
self.ready.eq(1),
If(error_seen,
checks_reset.i.eq(1),
self.restart.eq(1),
NextState("WAIT_COMMA")
)
)

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@ -3,14 +3,13 @@ from operator import or_
from migen import *
from migen.genlib.resetsync import AsyncResetSynchronizer
from migen.genlib.cdc import MultiReg
from misoc.interconnect.csr import *
from misoc.cores.code_8b10b import Encoder, Decoder
from microscope import *
from artiq.gateware.drtio.core import TransceiverInterface, ChannelInterface
from artiq.gateware.drtio.transceiver.clock_aligner import BruteforceClockAligner
from artiq.gateware.drtio.transceiver.gth_ultrascale_init import *

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@ -1,13 +1,11 @@
from math import ceil
from functools import reduce
from operator import add
from migen import *
from migen.genlib.cdc import MultiReg, PulseSynchronizer
from migen.genlib.misc import WaitTimer
__all__ = ["BruteforceClockAligner", "GTHInit"]
__all__ = ["GTHInit"]
class GTHInit(Module):
@ -140,111 +138,3 @@ class GTHInit(Module):
self.done.eq(1),
If(self.restart, NextState("RESET_ALL"))
)
# Changes the phase of the transceiver RX clock to align the comma to
# the LSBs of RXDATA, fixing the latency.
#
# This is implemented by repeatedly resetting the transceiver until it
# gives out the correct phase. Each reset gives a random phase.
#
# If Xilinx had designed the GTX transceiver correctly, RXSLIDE_MODE=PMA
# would achieve this faster and in a cleaner way. But:
# * the phase jumps are of 2 UI at every second RXSLIDE pulse, instead
# of 1 UI at every pulse. It is unclear what the latency becomes.
# * RXSLIDE_MODE=PMA cannot be used with the RX buffer bypassed.
# Those design flaws make RXSLIDE_MODE=PMA yet another broken and useless
# transceiver "feature".
#
# Warning: Xilinx transceivers are LSB first, and comma needs to be flipped
# compared to the usual 8b10b binary representation.
class BruteforceClockAligner(Module):
def __init__(self, comma, tx_clk_freq, check_period=6e-3):
self.rxdata = Signal(20)
self.restart = Signal()
self.ready = Signal()
check_max_val = ceil(check_period*tx_clk_freq)
check_counter = Signal(max=check_max_val+1)
check = Signal()
reset_check_counter = Signal()
self.sync.rtio_tx += [
check.eq(0),
If(reset_check_counter,
check_counter.eq(check_max_val)
).Else(
If(check_counter == 0,
check.eq(1),
check_counter.eq(check_max_val)
).Else(
check_counter.eq(check_counter-1)
)
)
]
checks_reset = PulseSynchronizer("rtio_tx", "rtio_rx")
self.submodules += checks_reset
comma_n = ~comma & 0b1111111111
comma_seen_rxclk = Signal()
comma_seen = Signal()
comma_seen_rxclk.attr.add("no_retiming")
self.specials += MultiReg(comma_seen_rxclk, comma_seen)
self.sync.rtio_rx += \
If(checks_reset.o,
comma_seen_rxclk.eq(0)
).Elif((self.rxdata[:10] == comma) | (self.rxdata[:10] == comma_n),
comma_seen_rxclk.eq(1)
)
error_seen_rxclk = Signal()
error_seen = Signal()
error_seen_rxclk.attr.add("no_retiming")
self.specials += MultiReg(error_seen_rxclk, error_seen)
rx1cnt = Signal(max=11)
self.sync.rtio_rx += [
rx1cnt.eq(reduce(add, [self.rxdata[i] for i in range(10)])),
If(checks_reset.o,
error_seen_rxclk.eq(0)
).Elif((rx1cnt != 4) & (rx1cnt != 5) & (rx1cnt != 6),
error_seen_rxclk.eq(1)
)
]
fsm = ClockDomainsRenamer("rtio_tx")(FSM(reset_state="WAIT_COMMA"))
self.submodules += fsm
fsm.act("WAIT_COMMA",
If(check,
# Errors are still OK at this stage, as the transceiver
# has just been reset and may output garbage data.
If(comma_seen,
NextState("WAIT_NOERROR")
).Else(
self.restart.eq(1)
),
checks_reset.i.eq(1)
)
)
fsm.act("WAIT_NOERROR",
If(check,
If(comma_seen & ~error_seen,
NextState("READY")
).Else(
self.restart.eq(1),
NextState("WAIT_COMMA")
),
checks_reset.i.eq(1)
)
)
fsm.act("READY",
reset_check_counter.eq(1),
self.ready.eq(1),
If(error_seen,
checks_reset.i.eq(1),
self.restart.eq(1),
NextState("WAIT_COMMA")
)
)

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@ -0,0 +1,251 @@
from functools import reduce
from operator import or_
from migen import *
from migen.genlib.resetsync import AsyncResetSynchronizer
from misoc.cores.code_8b10b import Encoder, Decoder
from artiq.gateware.drtio.core import TransceiverInterface, ChannelInterface
from artiq.gateware.drtio.transceiver.clock_aligner import BruteforceClockAligner
from artiq.gateware.drtio.transceiver.gtp_7series_init import *
class GTPSingle(Module):
def __init__(self, qpll_channel, tx_pads, rx_pads, sys_clk_freq, rtio_clk_freq, mode):
if mode != "master":
raise NotImplementedError
self.submodules.encoder = encoder = ClockDomainsRenamer("rtio_tx")(
Encoder(2, True))
self.submodules.decoders = decoders = [ClockDomainsRenamer("rtio_rx")(
(Decoder(True))) for _ in range(2)]
self.rx_ready = Signal()
# transceiver direct clock outputs
# useful to specify clock constraints in a way palatable to Vivado
self.txoutclk = Signal()
self.rxoutclk = Signal()
# # #
# TX generates RTIO clock, init must be in system domain
tx_init = GTPTXInit(sys_clk_freq)
# RX receives restart commands from RTIO domain
rx_init = ClockDomainsRenamer("rtio_tx")(GTPRXInit(rtio_clk_freq))
self.submodules += tx_init, rx_init
self.comb += [
qpll_channel.reset.eq(tx_init.pllreset),
tx_init.plllock.eq(qpll_channel.lock),
rx_init.plllock.eq(qpll_channel.lock),
]
txdata = Signal(20)
rxdata = Signal(20)
rxphaligndone = Signal()
self.specials += \
Instance("GTPE2_CHANNEL",
# Reset modes
i_GTRESETSEL=0,
i_RESETOVRD=0,
# DRP
i_DRPADDR=rx_init.drpaddr,
i_DRPCLK=ClockSignal("rtio_tx"),
i_DRPDI=rx_init.drpdi,
o_DRPDO=rx_init.drpdo,
i_DRPEN=rx_init.drpen,
o_DRPRDY=rx_init.drprdy,
i_DRPWE=rx_init.drpwe,
# PMA Attributes
p_PMA_RSV=0x333,
p_PMA_RSV2=0x2040,
p_PMA_RSV3=0,
p_PMA_RSV4=0,
p_RX_BIAS_CFG=0b0000111100110011,
p_RX_CM_SEL=0b01,
p_RX_CM_TRIM=0b1010,
p_RX_OS_CFG=0b10000000,
p_RXLPM_IPCM_CFG=1,
i_RXELECIDLEMODE=0b11,
i_RXOSINTCFG=0b0010,
i_RXOSINTEN=1,
# Power-Down Attributes
p_PD_TRANS_TIME_FROM_P2=0x3c,
p_PD_TRANS_TIME_NONE_P2=0x3c,
p_PD_TRANS_TIME_TO_P2=0x64,
# QPLL
i_PLL0CLK=qpll_channel.clk,
i_PLL0REFCLK=qpll_channel.refclk,
# TX clock
p_TXBUF_EN="FALSE",
p_TX_XCLK_SEL="TXUSR",
o_TXOUTCLK=self.txoutclk,
p_TXOUT_DIV=2,
i_TXSYSCLKSEL=0b00,
i_TXOUTCLKSEL=0b11,
# TX Startup/Reset
i_GTTXRESET=tx_init.gttxreset,
o_TXRESETDONE=tx_init.txresetdone,
p_TXSYNC_OVRD=1,
i_TXDLYSRESET=tx_init.txdlysreset,
o_TXDLYSRESETDONE=tx_init.txdlysresetdone,
i_TXPHINIT=tx_init.txphinit,
o_TXPHINITDONE=tx_init.txphinitdone,
i_TXPHALIGNEN=1,
i_TXPHALIGN=tx_init.txphalign,
o_TXPHALIGNDONE=tx_init.txphaligndone,
i_TXDLYEN=tx_init.txdlyen,
i_TXUSERRDY=tx_init.txuserrdy,
# TX data
p_TX_DATA_WIDTH=20,
i_TXCHARDISPMODE=Cat(txdata[9], txdata[19]),
i_TXCHARDISPVAL=Cat(txdata[8], txdata[18]),
i_TXDATA=Cat(txdata[:8], txdata[10:18]),
i_TXUSRCLK=ClockSignal("rtio_tx"),
i_TXUSRCLK2=ClockSignal("rtio_tx"),
# TX electrical
i_TXBUFDIFFCTRL=0b100,
i_TXDIFFCTRL=0b1000,
# RX Startup/Reset
i_GTRXRESET=rx_init.gtrxreset,
o_RXRESETDONE=rx_init.rxresetdone,
i_RXDLYSRESET=rx_init.rxdlysreset,
o_RXDLYSRESETDONE=rx_init.rxdlysresetdone,
o_RXPHALIGNDONE=rxphaligndone,
i_RXSYNCALLIN=rxphaligndone,
i_RXUSERRDY=rx_init.rxuserrdy,
i_RXSYNCIN=0,
i_RXSYNCMODE=1,
p_RXSYNC_MULTILANE=0,
p_RXSYNC_OVRD=0,
o_RXSYNCDONE=rx_init.rxsyncdone,
p_RXPMARESET_TIME=0b11,
o_RXPMARESETDONE=rx_init.rxpmaresetdone,
# RX clock
p_RX_CLK25_DIV=5,
p_TX_CLK25_DIV=5,
p_RX_XCLK_SEL="RXUSR",
p_RXOUT_DIV=2,
i_RXSYSCLKSEL=0b00,
i_RXOUTCLKSEL=0b010,
o_RXOUTCLK=self.rxoutclk,
i_RXUSRCLK=ClockSignal("rtio_rx"),
i_RXUSRCLK2=ClockSignal("rtio_rx"),
p_RXCDR_CFG=0x0000107FE206001041010,
p_RXPI_CFG1=1,
p_RXPI_CFG2=1,
# RX Clock Correction Attributes
p_CLK_CORRECT_USE="FALSE",
# RX data
p_RXBUF_EN="FALSE",
p_RXDLY_CFG=0x001f,
p_RXDLY_LCFG=0x030,
p_RXPHDLY_CFG=0x084020,
p_RXPH_CFG=0xc00002,
p_RX_DATA_WIDTH=20,
i_RXCOMMADETEN=1,
i_RXDLYBYPASS=0,
i_RXDDIEN=1,
o_RXDISPERR=Cat(rxdata[9], rxdata[19]),
o_RXCHARISK=Cat(rxdata[8], rxdata[18]),
o_RXDATA=Cat(rxdata[:8], rxdata[10:18]),
# Pads
i_GTPRXP=rx_pads.p,
i_GTPRXN=rx_pads.n,
o_GTPTXP=tx_pads.p,
o_GTPTXN=tx_pads.n
)
# tx clocking
tx_reset_deglitched = Signal()
tx_reset_deglitched.attr.add("no_retiming")
self.sync += tx_reset_deglitched.eq(~tx_init.done)
self.clock_domains.cd_rtio_tx = ClockDomain()
if mode == "master":
txoutclk_bufg = Signal()
txoutclk_bufr = Signal()
tx_bufr_div = 150.e6/rtio_clk_freq
assert tx_bufr_div == int(tx_bufr_div)
self.specials += [
Instance("BUFG", i_I=self.txoutclk, o_O=txoutclk_bufg),
Instance("BUFR", i_I=txoutclk_bufg, o_O=txoutclk_bufr,
i_CE=1, p_BUFR_DIVIDE=str(int(tx_bufr_div))),
Instance("BUFG", i_I=txoutclk_bufr, o_O=self.cd_rtio_tx.clk)
]
self.specials += AsyncResetSynchronizer(self.cd_rtio_tx, tx_reset_deglitched)
# rx clocking
rx_reset_deglitched = Signal()
rx_reset_deglitched.attr.add("no_retiming")
self.sync.rtio_tx += rx_reset_deglitched.eq(~rx_init.done)
self.clock_domains.cd_rtio_rx = ClockDomain()
self.specials += [
Instance("BUFG", i_I=self.rxoutclk, o_O=self.cd_rtio_rx.clk),
AsyncResetSynchronizer(self.cd_rtio_rx, rx_reset_deglitched)
]
# tx data
self.comb += txdata.eq(Cat(*[encoder.output[i] for i in range(2)]))
# rx data
for i in range(2):
self.comb += decoders[i].input.eq(rxdata[10*i:10*(i+1)])
# clock alignment
clock_aligner = BruteforceClockAligner(0b0101111100, rtio_clk_freq, check_period=10e-3)
self.submodules += clock_aligner
self.comb += [
clock_aligner.rxdata.eq(rxdata),
rx_init.restart.eq(clock_aligner.restart),
self.rx_ready.eq(clock_aligner.ready)
]
class GTP(Module, TransceiverInterface):
def __init__(self, qpll_channel, tx_pads, rx_pads, sys_clk_freq, rtio_clk_freq, master=0):
self.nchannels = nchannels = len(tx_pads)
self.gtps = []
if nchannels >= 1:
raise NotImplementedError
# # #
rtio_tx_clk = Signal()
channel_interfaces = []
for i in range(nchannels):
mode = "master" if i == master else "slave"
gtp = GTPSingle(qpll_channel, tx_pads[i], rx_pads[i], sys_clk_freq, rtio_clk_freq, mode)
if mode == "master":
self.comb += rtio_tx_clk.eq(gtp.cd_rtio_tx.clk)
else:
self.comb += gtp.cd_rtio_tx.clk.eq(rtio_tx_clk)
self.gtps.append(gtp)
setattr(self.submodules, "gtp"+str(i), gtp)
channel_interface = ChannelInterface(gtp.encoder, gtp.decoders)
self.comb += channel_interface.rx_ready.eq(gtp.rx_ready)
channel_interfaces.append(channel_interface)
TransceiverInterface.__init__(self, channel_interfaces)
self.comb += [
self.cd_rtio.clk.eq(self.gtps[master].cd_rtio_tx.clk),
self.cd_rtio.rst.eq(reduce(or_, [gtp.cd_rtio_tx.rst for gtp in self.gtps]))
]
for i in range(nchannels):
self.comb += [
getattr(self, "cd_rtio_rx" + str(i)).clk.eq(self.gtps[i].cd_rtio_rx.clk),
getattr(self, "cd_rtio_rx" + str(i)).rst.eq(self.gtps[i].cd_rtio_rx.rst)
]

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@ -0,0 +1,305 @@
from math import ceil
from migen import *
from migen.genlib.cdc import MultiReg, PulseSynchronizer
from migen.genlib.misc import WaitTimer
__all__ = ["GTPTXInit", "GTPRXInit"]
class GTPTXInit(Module):
def __init__(self, sys_clk_freq):
self.done = Signal()
self.restart = Signal()
# GTP signals
self.plllock = Signal()
self.pllreset = Signal()
self.gttxreset = Signal()
self.txresetdone = Signal()
self.txdlysreset = Signal()
self.txdlysresetdone = Signal()
self.txphinit = Signal()
self.txphinitdone = Signal()
self.txphalign = Signal()
self.txphaligndone = Signal()
self.txdlyen = Signal()
self.txuserrdy = Signal()
# # #
# Double-latch transceiver asynch outputs
plllock = Signal()
txresetdone = Signal()
txdlysresetdone = Signal()
txphinitdone = Signal()
txphaligndone = Signal()
self.specials += [
MultiReg(self.plllock, plllock),
MultiReg(self.txresetdone, txresetdone),
MultiReg(self.txdlysresetdone, txdlysresetdone),
MultiReg(self.txphinitdone, txphinitdone),
MultiReg(self.txphaligndone, txphaligndone)
]
# Deglitch FSM outputs driving transceiver asynch inputs
gttxreset = Signal()
txdlysreset = Signal()
txphinit = Signal()
txphalign = Signal()
txdlyen = Signal()
txuserrdy = Signal()
self.sync += [
self.gttxreset.eq(gttxreset),
self.txdlysreset.eq(txdlysreset),
self.txphinit.eq(txphinit),
self.txphalign.eq(txphalign),
self.txdlyen.eq(txdlyen),
self.txuserrdy.eq(txuserrdy)
]
# PLL reset must be at least 500us
pll_reset_cycles = ceil(500e-9*sys_clk_freq)
pll_reset_timer = WaitTimer(pll_reset_cycles)
self.submodules += pll_reset_timer
startup_fsm = ResetInserter()(FSM(reset_state="PLL_RESET"))
self.submodules += startup_fsm
ready_timer = WaitTimer(int(1e-3*sys_clk_freq))
self.submodules += ready_timer
self.comb += [
ready_timer.wait.eq(~self.done & ~startup_fsm.reset),
startup_fsm.reset.eq(self.restart | ready_timer.done)
]
txphaligndone_r = Signal(reset=1)
txphaligndone_rising = Signal()
self.sync += txphaligndone_r.eq(txphaligndone)
self.comb += txphaligndone_rising.eq(txphaligndone & ~txphaligndone_r)
startup_fsm.act("PLL_RESET",
self.pllreset.eq(1),
pll_reset_timer.wait.eq(1),
If(pll_reset_timer.done,
NextState("GTP_RESET")
)
)
startup_fsm.act("GTP_RESET",
gttxreset.eq(1),
If(plllock,
NextState("WAIT_GTP_RESET_DONE")
)
)
# Release GTP reset and wait for GTP resetdone
# (from UG482, GTP is reset on falling edge
# of gttxreset)
startup_fsm.act("WAIT_GTP_RESET_DONE",
txuserrdy.eq(1),
If(txresetdone, NextState("ALIGN"))
)
# Start delay alignment
startup_fsm.act("ALIGN",
txuserrdy.eq(1),
txdlysreset.eq(1),
If(txdlysresetdone,
NextState("PHALIGN")
)
)
# Start phase alignment
startup_fsm.act("PHALIGN",
txuserrdy.eq(1),
txphinit.eq(1),
If(txphinitdone,
NextState("WAIT_FIRST_ALIGN_DONE")
)
)
# Wait 2 rising edges of Xxphaligndone
# (from UG482 in TX Buffer Bypass in Single-Lane Auto Mode)
startup_fsm.act("WAIT_FIRST_ALIGN_DONE",
txuserrdy.eq(1),
txphalign.eq(1),
If(txphaligndone_rising,
NextState("WAIT_SECOND_ALIGN_DONE")
)
)
startup_fsm.act("WAIT_SECOND_ALIGN_DONE",
txuserrdy.eq(1),
txdlyen.eq(1),
If(txphaligndone_rising,
NextState("READY")
)
)
startup_fsm.act("READY",
txuserrdy.eq(1),
self.done.eq(1),
If(self.restart, NextState("PLL_RESET"))
)
class GTPRXInit(Module):
def __init__(self, sys_clk_freq):
self.done = Signal()
self.restart = Signal()
# GTP signals
self.plllock = Signal()
self.gtrxreset = Signal()
self.rxresetdone = Signal()
self.rxdlysreset = Signal()
self.rxdlysresetdone = Signal()
self.rxphalign = Signal()
self.rxdlyen = Signal()
self.rxuserrdy = Signal()
self.rxsyncdone = Signal()
self.rxpmaresetdone = Signal()
self.drpaddr = Signal(9)
self.drpen = Signal()
self.drpdi = Signal(16)
self.drprdy = Signal()
self.drpdo = Signal(16)
self.drpwe = Signal()
# # #
drpvalue = Signal(16)
drpmask = Signal()
self.comb += [
self.drpaddr.eq(0x011),
If(drpmask,
self.drpdi.eq(drpvalue & 0xf7ff)
).Else(
self.drpdi.eq(drpvalue)
)
]
rxpmaresetdone = Signal()
self.specials += MultiReg(self.rxpmaresetdone, rxpmaresetdone)
rxpmaresetdone_r = Signal()
self.sync += rxpmaresetdone_r.eq(rxpmaresetdone)
# Double-latch transceiver asynch outputs
plllock = Signal()
rxresetdone = Signal()
rxdlysresetdone = Signal()
rxsyncdone = Signal()
self.specials += [
MultiReg(self.plllock, plllock),
MultiReg(self.rxresetdone, rxresetdone),
MultiReg(self.rxdlysresetdone, rxdlysresetdone),
MultiReg(self.rxsyncdone, rxsyncdone)
]
# Deglitch FSM outputs driving transceiver asynch inputs
gtrxreset = Signal()
rxdlysreset = Signal()
rxphalign = Signal()
rxdlyen = Signal()
rxuserrdy = Signal()
self.sync += [
self.gtrxreset.eq(gtrxreset),
self.rxdlysreset.eq(rxdlysreset),
self.rxphalign.eq(rxphalign),
self.rxdlyen.eq(rxdlyen),
self.rxuserrdy.eq(rxuserrdy)
]
# After configuration, transceiver resets have to stay low for
# at least 500ns (see AR43482)
pll_reset_cycles = ceil(500e-9*sys_clk_freq)
pll_reset_timer = WaitTimer(pll_reset_cycles)
self.submodules += pll_reset_timer
startup_fsm = ResetInserter()(FSM(reset_state="GTP_RESET"))
self.submodules += startup_fsm
ready_timer = WaitTimer(int(4e-3*sys_clk_freq))
self.submodules += ready_timer
self.comb += [
ready_timer.wait.eq(~self.done & ~startup_fsm.reset),
startup_fsm.reset.eq(self.restart | ready_timer.done)
]
cdr_stable_timer = WaitTimer(1024)
self.submodules += cdr_stable_timer
startup_fsm.act("GTP_RESET",
gtrxreset.eq(1),
NextState("DRP_READ_ISSUE")
)
startup_fsm.act("DRP_READ_ISSUE",
gtrxreset.eq(1),
self.drpen.eq(1),
NextState("DRP_READ_WAIT")
)
startup_fsm.act("DRP_READ_WAIT",
gtrxreset.eq(1),
If(self.drprdy,
NextValue(drpvalue, self.drpdo),
NextState("DRP_MOD_ISSUE")
)
)
startup_fsm.act("DRP_MOD_ISSUE",
gtrxreset.eq(1),
drpmask.eq(1),
self.drpen.eq(1),
self.drpwe.eq(1),
NextState("DRP_MOD_WAIT")
)
startup_fsm.act("DRP_MOD_WAIT",
gtrxreset.eq(1),
If(self.drprdy,
NextState("WAIT_PMARST_FALL")
)
)
startup_fsm.act("WAIT_PMARST_FALL",
rxuserrdy.eq(1),
If(rxpmaresetdone_r & ~rxpmaresetdone,
NextState("DRP_RESTORE_ISSUE")
)
)
startup_fsm.act("DRP_RESTORE_ISSUE",
rxuserrdy.eq(1),
self.drpen.eq(1),
self.drpwe.eq(1),
NextState("DRP_RESTORE_WAIT")
)
startup_fsm.act("DRP_RESTORE_WAIT",
rxuserrdy.eq(1),
If(self.drprdy,
NextState("WAIT_GTP_RESET_DONE")
)
)
# Release GTP reset and wait for GTP resetdone
# (from UG482, GTP is reset on falling edge
# of gtrxreset)
startup_fsm.act("WAIT_GTP_RESET_DONE",
rxuserrdy.eq(1),
cdr_stable_timer.wait.eq(1),
If(rxresetdone & cdr_stable_timer.done,
NextState("ALIGN")
)
)
# Start delay alignment
startup_fsm.act("ALIGN",
rxuserrdy.eq(1),
rxdlysreset.eq(1),
If(rxdlysresetdone,
NextState("WAIT_ALIGN_DONE")
)
)
# Wait for delay alignment
startup_fsm.act("WAIT_ALIGN_DONE",
rxuserrdy.eq(1),
If(rxsyncdone,
NextState("READY")
)
)
startup_fsm.act("READY",
rxuserrdy.eq(1),
self.done.eq(1),
If(self.restart, NextState("GTP_RESET")
)
)