from migen.fhdl.structure import *
from migen.fhdl import verilog
from migen.genlib.fsm import FSM
s = Signal()
myfsm = FSM("FOO", "BAR")
myfsm.act(myfsm.FOO, s.eq(1), myfsm.next_state(myfsm.BAR))
myfsm.act(myfsm.BAR, s.eq(0), myfsm.next_state(myfsm.FOO))
print(verilog.convert(myfsm.get_fragment(), {s}))
def __init__(self):
self.s = Signal()
myfsm = FSM("FOO", "BAR")
self.submodules += myfsm
myfsm.act(myfsm.FOO, self.s.eq(1), myfsm.next_state(myfsm.BAR))
myfsm.act(myfsm.BAR, self.s.eq(0), myfsm.next_state(myfsm.FOO))
def __init__(self, pads, default=_default_edid): self.specials.mem = Memory(8, 128, init=default) ### scl_raw = Signal() sda_i = Signal() sda_drv = Signal() _sda_drv_reg = Signal() _sda_i_async = Signal() self.sync += _sda_drv_reg.eq(sda_drv) self.specials += [ MultiReg(pads.scl, scl_raw), Tristate(pads.sda, 0, _sda_drv_reg, _sda_i_async), MultiReg(_sda_i_async, sda_i) ] scl_i = Signal() samp_count = Signal(6) samp_carry = Signal() self.sync += [ Cat(samp_count, samp_carry).eq(samp_count + 1), If(samp_carry, scl_i.eq(scl_raw)) ] scl_r = Signal() sda_r = Signal() scl_rising = Signal() sda_rising = Signal() sda_falling = Signal() self.sync += [ scl_r.eq(scl_i), sda_r.eq(sda_i) ] self.comb += [ scl_rising.eq(scl_i & ~scl_r), sda_rising.eq(sda_i & ~sda_r), sda_falling.eq(~sda_i & sda_r) ] start = Signal() self.comb += start.eq(scl_i & sda_falling) din = Signal(8) counter = Signal(max=9) self.sync += [ If(start, counter.eq(0)), If(scl_rising, If(counter == 8, counter.eq(0) ).Else( counter.eq(counter + 1), din.eq(Cat(sda_i, din[:7])) ) ) ] is_read = Signal() update_is_read = Signal() self.sync += If(update_is_read, is_read.eq(din[0])) offset_counter = Signal(max=128) oc_load = Signal() oc_inc = Signal() self.sync += [ If(oc_load, offset_counter.eq(din) ).Elif(oc_inc, offset_counter.eq(offset_counter + 1) ) ] rdport = self.mem.get_port() self.comb += rdport.adr.eq(offset_counter) data_bit = Signal() zero_drv = Signal() data_drv = Signal() self.comb += If(zero_drv, sda_drv.eq(1)).Elif(data_drv, sda_drv.eq(~data_bit)) data_drv_en = Signal() data_drv_stop = Signal() self.sync += If(data_drv_en, data_drv.eq(1)).Elif(data_drv_stop, data_drv.eq(0)) self.sync += If(data_drv_en, chooser(rdport.dat_r, counter, data_bit, 8, reverse=True)) states = ["WAIT_START", "RCV_ADDRESS", "ACK_ADDRESS0", "ACK_ADDRESS1", "ACK_ADDRESS2", "RCV_OFFSET", "ACK_OFFSET0", "ACK_OFFSET1", "ACK_OFFSET2", "READ", "ACK_READ"] fsm = FSM(*states) self.submodules += fsm fsm.act(fsm.RCV_ADDRESS, If(counter == 8, If(din[1:] == 0x50, update_is_read.eq(1), fsm.next_state(fsm.ACK_ADDRESS0) ).Else( fsm.next_state(fsm.WAIT_START) ) ) ) fsm.act(fsm.ACK_ADDRESS0, If(~scl_i, fsm.next_state(fsm.ACK_ADDRESS1)) ) fsm.act(fsm.ACK_ADDRESS1, zero_drv.eq(1), If(scl_i, fsm.next_state(fsm.ACK_ADDRESS2)) ) fsm.act(fsm.ACK_ADDRESS2, zero_drv.eq(1), If(~scl_i, If(is_read, fsm.next_state(fsm.READ) ).Else( fsm.next_state(fsm.RCV_OFFSET) ) ) ) fsm.act(fsm.RCV_OFFSET, If(counter == 8, oc_load.eq(1), fsm.next_state(fsm.ACK_OFFSET0) ) ) fsm.act(fsm.ACK_OFFSET0, If(~scl_i, fsm.next_state(fsm.ACK_OFFSET1)) ) fsm.act(fsm.ACK_OFFSET1, zero_drv.eq(1), If(scl_i, fsm.next_state(fsm.ACK_OFFSET2)) ) fsm.act(fsm.ACK_OFFSET2, zero_drv.eq(1), If(~scl_i, fsm.next_state(fsm.RCV_ADDRESS)) ) fsm.act(fsm.READ, If(~scl_i, If(counter == 8, data_drv_stop.eq(1), fsm.next_state(fsm.ACK_READ) ).Else( data_drv_en.eq(1) ) ) ) fsm.act(fsm.ACK_READ, If(scl_rising, oc_inc.eq(1), If(sda_i, fsm.next_state(fsm.WAIT_START) ).Else( fsm.next_state(fsm.READ) ) ) ) for state in states: fsm.act(getattr(fsm, state), If(start, fsm.next_state(fsm.RCV_ADDRESS)))
def __init__(self, cachesize, lasmim):
self.wishbone = wishbone.Interface()
###
if lasmim.dw <= 32:
raise ValueError("LASMI data width must be strictly larger than 32")
if (lasmim.dw % 32) != 0:
raise ValueError("LASMI data width must be a multiple of 32")
# Split address:
# TAG | LINE NUMBER | LINE OFFSET
offsetbits = log2_int(lasmim.dw//32)
addressbits = lasmim.aw + offsetbits
linebits = log2_int(cachesize) - offsetbits
tagbits = addressbits - linebits
adr_offset, adr_line, adr_tag = split(self.wishbone.adr, offsetbits, linebits, tagbits)
# Data memory
data_mem = Memory(lasmim.dw, 2**linebits)
data_port = data_mem.get_port(write_capable=True, we_granularity=8)
self.specials += data_mem, data_port
write_from_lasmi = Signal()
write_to_lasmi = Signal()
adr_offset_r = Signal(offsetbits)
self.comb += [
data_port.adr.eq(adr_line),
If(write_from_lasmi,
data_port.dat_w.eq(lasmim.dat_r),
data_port.we.eq(Replicate(1, lasmim.dw//8))
).Else(
data_port.dat_w.eq(Replicate(self.wishbone.dat_w, lasmim.dw//32)),
If(self.wishbone.cyc & self.wishbone.stb & self.wishbone.we & self.wishbone.ack,
displacer(self.wishbone.sel, adr_offset, data_port.we, 2**offsetbits, reverse=True)
)
),
If(write_to_lasmi,
lasmim.dat_w.eq(data_port.dat_r),
lasmim.dat_we.eq(2**(lasmim.dw//8)-1)
),
chooser(data_port.dat_r, adr_offset_r, self.wishbone.dat_r, reverse=True)
]
self.sync += adr_offset_r.eq(adr_offset)
# Tag memory
tag_layout = [("tag", tagbits), ("dirty", 1)]
tag_mem = Memory(layout_len(tag_layout), 2**linebits)
tag_port = tag_mem.get_port(write_capable=True)
self.specials += tag_mem, tag_port
tag_do = Record(tag_layout)
tag_di = Record(tag_layout)
self.comb += [
tag_do.raw_bits().eq(tag_port.dat_r),
tag_port.dat_w.eq(tag_di.raw_bits())
]
self.comb += [
tag_port.adr.eq(adr_line),
tag_di.tag.eq(adr_tag),
lasmim.adr.eq(Cat(adr_line, tag_do.tag))
]
# Control FSM
assert(lasmim.write_latency >= 1 and lasmim.read_latency >= 1)
fsm = FSM("IDLE", "TEST_HIT",
"EVICT_REQUEST", "EVICT_WAIT_DATA_ACK", "EVICT_DATA",
"REFILL_WRTAG", "REFILL_REQUEST", "REFILL_WAIT_DATA_ACK", "REFILL_DATA",
delayed_enters=[
("EVICT_DATAD", "EVICT_DATA", lasmim.write_latency-1),
("REFILL_DATAD", "REFILL_DATA", lasmim.read_latency-1)
])
self.submodules += fsm
fsm.act(fsm.IDLE,
If(self.wishbone.cyc & self.wishbone.stb, fsm.next_state(fsm.TEST_HIT))
)
fsm.act(fsm.TEST_HIT,
If(tag_do.tag == adr_tag,
self.wishbone.ack.eq(1),
If(self.wishbone.we,
tag_di.dirty.eq(1),
tag_port.we.eq(1)
),
fsm.next_state(fsm.IDLE)
).Else(
If(tag_do.dirty,
fsm.next_state(fsm.EVICT_REQUEST)
).Else(
fsm.next_state(fsm.REFILL_WRTAG)
)
)
)
fsm.act(fsm.EVICT_REQUEST,
lasmim.stb.eq(1),
lasmim.we.eq(1),
If(lasmim.req_ack, fsm.next_state(fsm.EVICT_WAIT_DATA_ACK))
)
fsm.act(fsm.EVICT_WAIT_DATA_ACK,
If(lasmim.dat_ack, fsm.next_state(fsm.EVICT_DATAD))
)
fsm.act(fsm.EVICT_DATA,
write_to_lasmi.eq(1),
fsm.next_state(fsm.REFILL_WRTAG)
)
fsm.act(fsm.REFILL_WRTAG,
# Write the tag first to set the LASMI address
tag_port.we.eq(1),
fsm.next_state(fsm.REFILL_REQUEST)
)
fsm.act(fsm.REFILL_REQUEST,
lasmim.stb.eq(1),
If(lasmim.req_ack, fsm.next_state(fsm.REFILL_WAIT_DATA_ACK))
)
fsm.act(fsm.REFILL_WAIT_DATA_ACK,
If(lasmim.dat_ack, fsm.next_state(fsm.REFILL_DATAD))
)
fsm.act(fsm.REFILL_DATA,
write_from_lasmi.eq(1),
fsm.next_state(fsm.TEST_HIT)
)
def __init__(self, a, ba, tRP, tREFI, tRFC):
self.req = Signal()
self.ack = Signal() # 1st command 1 cycle after assertion of ack
self.cmd = CommandRequest(a, ba)
###
# Refresh sequence generator:
# PRECHARGE ALL --(tRP)--> AUTO REFRESH --(tRFC)--> done
seq_start = Signal()
seq_done = Signal()
self.sync += [
self.cmd.a.eq(2**10),
self.cmd.ba.eq(0),
self.cmd.cas_n.eq(1),
self.cmd.ras_n.eq(1),
self.cmd.we_n.eq(1),
seq_done.eq(0)
]
self.sync += timeline(seq_start, [
(1, [
self.cmd.ras_n.eq(0),
self.cmd.we_n.eq(0)
]),
(1+tRP, [
self.cmd.cas_n.eq(0),
self.cmd.ras_n.eq(0)
]),
(1+tRP+tRFC, [
seq_done.eq(1)
])
])
# Periodic refresh counter
counter = Signal(max=tREFI)
start = Signal()
self.sync += [
start.eq(0),
If(counter == 0,
start.eq(1),
counter.eq(tREFI - 1)
).Else(
counter.eq(counter - 1)
)
]
# Control FSM
fsm = FSM("IDLE", "WAIT_GRANT", "WAIT_SEQ")
self.submodules += fsm
fsm.act(fsm.IDLE, If(start, fsm.next_state(fsm.WAIT_GRANT)))
fsm.act(fsm.WAIT_GRANT,
self.req.eq(1),
If(self.ack,
seq_start.eq(1),
fsm.next_state(fsm.WAIT_SEQ)
)
)
fsm.act(fsm.WAIT_SEQ,
self.req.eq(1),
If(seq_done, fsm.next_state(fsm.IDLE))
)
def get_fragment(self):
comb = []
sync = []
aaw = self.asmiport.hub.aw
adw = self.asmiport.hub.dw
# Split address:
# TAG | LINE NUMBER | LINE OFFSET
offsetbits = log2_int(adw//32)
addressbits = aaw + offsetbits
linebits = log2_int(self.cachesize) - offsetbits
tagbits = addressbits - linebits
adr_offset, adr_line, adr_tag = split(self.wishbone.adr, offsetbits, linebits, tagbits)
# Data memory
data_mem = Memory(adw, 2**linebits)
data_port = data_mem.get_port(write_capable=True, we_granularity=8)
write_from_asmi = Signal()
write_to_asmi = Signal()
adr_offset_r = Signal(offsetbits)
comb += [
data_port.adr.eq(adr_line),
If(write_from_asmi,
data_port.dat_w.eq(self.asmiport.dat_r),
data_port.we.eq(Replicate(1, adw//8))
).Else(
data_port.dat_w.eq(Replicate(self.wishbone.dat_w, adw//32)),
If(self.wishbone.cyc & self.wishbone.stb & self.wishbone.we & self.wishbone.ack,
displacer(self.wishbone.sel, adr_offset, data_port.we, 2**offsetbits, reverse=True)
)
),
If(write_to_asmi, self.asmiport.dat_w.eq(data_port.dat_r)),
self.asmiport.dat_wm.eq(0),
chooser(data_port.dat_r, adr_offset_r, self.wishbone.dat_r, reverse=True)
]
sync += [
adr_offset_r.eq(adr_offset)
]
# Tag memory
tag_layout = [("tag", tagbits), ("dirty", 1)]
tag_mem = Memory(layout_len(tag_layout), 2**linebits)
tag_port = tag_mem.get_port(write_capable=True)
tag_do = Record(tag_layout)
tag_di = Record(tag_layout)
comb += [
tag_do.raw_bits().eq(tag_port.dat_r),
tag_port.dat_w.eq(tag_di.raw_bits())
]
comb += [
tag_port.adr.eq(adr_line),
tag_di.tag.eq(adr_tag),
self.asmiport.adr.eq(Cat(adr_line, tag_do.tag))
]
# Control FSM
write_to_asmi_pre = Signal()
sync.append(write_to_asmi.eq(write_to_asmi_pre))
fsm = FSM("IDLE", "TEST_HIT",
"EVICT_ISSUE", "EVICT_WAIT",
"REFILL_WRTAG", "REFILL_ISSUE", "REFILL_WAIT", "REFILL_COMPLETE")
fsm.act(fsm.IDLE,
If(self.wishbone.cyc & self.wishbone.stb, fsm.next_state(fsm.TEST_HIT))
)
fsm.act(fsm.TEST_HIT,
If(tag_do.tag == adr_tag,
self.wishbone.ack.eq(1),
If(self.wishbone.we,
tag_di.dirty.eq(1),
tag_port.we.eq(1)
),
fsm.next_state(fsm.IDLE)
).Else(
If(tag_do.dirty,
fsm.next_state(fsm.EVICT_ISSUE)
).Else(
fsm.next_state(fsm.REFILL_WRTAG)
)
)
)
fsm.act(fsm.EVICT_ISSUE,
self.asmiport.stb.eq(1),
self.asmiport.we.eq(1),
If(self.asmiport.ack, fsm.next_state(fsm.EVICT_WAIT))
)
fsm.act(fsm.EVICT_WAIT,
# Data is actually sampled by the memory controller in the next state.
# But since the data memory has one cycle latency, it gets the data
# at the address given during this cycle.
If(self.asmiport.get_call_expression(),
write_to_asmi_pre.eq(1),
fsm.next_state(fsm.REFILL_WRTAG)
)
)
fsm.act(fsm.REFILL_WRTAG,
# Write the tag first to set the ASMI address
tag_port.we.eq(1),
fsm.next_state(fsm.REFILL_ISSUE)
)
fsm.act(fsm.REFILL_ISSUE,
self.asmiport.stb.eq(1),
If(self.asmiport.ack, fsm.next_state(fsm.REFILL_WAIT))
)
fsm.act(fsm.REFILL_WAIT,
If(self.asmiport.get_call_expression(), fsm.next_state(fsm.REFILL_COMPLETE))
)
fsm.act(fsm.REFILL_COMPLETE,
write_from_asmi.eq(1),
fsm.next_state(fsm.TEST_HIT)
)
return Fragment(comb, sync, specials={data_mem, tag_mem}) \
+ fsm.get_fragment()
def __init__(self, phy_settings, geom_settings, timing_settings, bank_machines, refresher, dfi, hub):
assert(phy_settings.nphases == len(dfi.phases))
if phy_settings.nphases != 2:
raise NotImplementedError("TODO: multiplexer only supports 2 phases")
# Command choosing
requests = [bm.cmd for bm in bank_machines]
tagbits = len(hub.tag_call)
choose_cmd = _CommandChooser(requests, tagbits)
choose_req = _CommandChooser(requests, tagbits)
self.comb += [
choose_cmd.want_reads.eq(0),
choose_cmd.want_writes.eq(0)
]
self.submodules += choose_cmd, choose_req
# Command steering
nop = CommandRequest(geom_settings.mux_a, geom_settings.bank_a)
commands = [nop, choose_cmd.cmd, choose_req.cmd, refresher.cmd] # nop must be 1st
(STEER_NOP, STEER_CMD, STEER_REQ, STEER_REFRESH) = range(4)
steerer = _Steerer(commands, dfi)
self.submodules += steerer
# Read/write turnaround
read_available = Signal()
write_available = Signal()
self.comb += [
read_available.eq(optree("|", [req.stb & req.is_read for req in requests])),
write_available.eq(optree("|", [req.stb & req.is_write for req in requests]))
]
def anti_starvation(timeout):
en = Signal()
max_time = Signal()
if timeout:
t = timeout - 1
time = Signal(max=t+1)
self.comb += max_time.eq(time == 0)
self.sync += If(~en,
time.eq(t)
).Elif(~max_time,
time.eq(time - 1)
)
else:
self.comb += max_time.eq(0)
return en, max_time
read_time_en, max_read_time = anti_starvation(timing_settings.read_time)
write_time_en, max_write_time = anti_starvation(timing_settings.write_time)
# Refresh
self.comb += [bm.refresh_req.eq(refresher.req) for bm in bank_machines]
go_to_refresh = Signal()
self.comb += go_to_refresh.eq(optree("&", [bm.refresh_gnt for bm in bank_machines]))
# Datapath
datapath = _Datapath(timing_settings, choose_req.cmd, dfi, hub)
self.submodules += datapath
# Control FSM
fsm = FSM("READ", "WRITE", "REFRESH", delayed_enters=[
("RTW", "WRITE", timing_settings.rd_delay),
("WTR", "READ", timing_settings.tWR)
])
self.submodules += fsm
fsm.act(fsm.READ,
read_time_en.eq(1),
choose_req.want_reads.eq(1),
choose_cmd.cmd.ack.eq(1),
choose_req.cmd.ack.eq(1),
steerer.sel[1-phy_settings.rdphase].eq(STEER_CMD),
steerer.sel[phy_settings.rdphase].eq(STEER_REQ),
If(write_available,
# TODO: switch only after several cycles of ~read_available?
If(~read_available | max_read_time, fsm.next_state(fsm.RTW))
),
If(go_to_refresh, fsm.next_state(fsm.REFRESH))
)
fsm.act(fsm.WRITE,
write_time_en.eq(1),
choose_req.want_writes.eq(1),
choose_cmd.cmd.ack.eq(1),
choose_req.cmd.ack.eq(1),
steerer.sel[1-phy_settings.wrphase].eq(STEER_CMD),
steerer.sel[phy_settings.wrphase].eq(STEER_REQ),
If(read_available,
If(~write_available | max_write_time, fsm.next_state(fsm.WTR))
),
If(go_to_refresh, fsm.next_state(fsm.REFRESH))
)
fsm.act(fsm.REFRESH,
steerer.sel[0].eq(STEER_REFRESH),
If(~refresher.req, fsm.next_state(fsm.READ))
)
# FIXME: workaround for zero-delay loop simulation problem with Icarus Verilog
self.comb += refresher.ack.eq(fsm._state == fsm.REFRESH)
def __init__(self, geom_settings, timing_settings, address_align, bankn, slots, full_selector):
self.refresh_req = Signal()
self.refresh_gnt = Signal()
self.cmd = CommandRequestRW(geom_settings.mux_a, geom_settings.bank_a,
bits_for(len(slots)-1))
###
# Sub components
slicer = _AddressSlicer(geom_settings, address_align)
if full_selector:
selector = _FullSelector(slicer, bankn, slots)
self.submodules.buf = _Buffer(selector)
cmdsource = self.buf
else:
selector = _SimpleSelector(slicer, bankn, slots)
cmdsource = selector
self.submodules += selector
# Row tracking
has_openrow = Signal()
openrow = Signal(geom_settings.row_a)
hit = Signal()
self.comb += hit.eq(openrow == slicer.row(cmdsource.adr))
track_open = Signal()
track_close = Signal()
self.sync += [
If(track_open,
has_openrow.eq(1),
openrow.eq(slicer.row(cmdsource.adr))
),
If(track_close,
has_openrow.eq(0)
)
]
# Address generation
s_row_adr = Signal()
self.comb += [
self.cmd.ba.eq(bankn),
If(s_row_adr,
self.cmd.a.eq(slicer.row(cmdsource.adr))
).Else(
self.cmd.a.eq(slicer.col(cmdsource.adr))
)
]
self.comb += self.cmd.tag.eq(cmdsource.tag)
# Respect write-to-precharge specification
precharge_ok = Signal()
t_unsafe_precharge = 2 + timing_settings.tWR - 1
unsafe_precharge_count = Signal(max=t_unsafe_precharge+1)
self.comb += precharge_ok.eq(unsafe_precharge_count == 0)
self.sync += [
If(self.cmd.stb & self.cmd.ack & self.cmd.is_write,
unsafe_precharge_count.eq(t_unsafe_precharge)
).Elif(~precharge_ok,
unsafe_precharge_count.eq(unsafe_precharge_count-1)
)
]
# Control and command generation FSM
fsm = FSM("REGULAR", "PRECHARGE", "ACTIVATE", "REFRESH", delayed_enters=[
("TRP", "ACTIVATE", timing_settings.tRP-1),
("TRCD", "REGULAR", timing_settings.tRCD-1)
])
self.submodules += fsm
fsm.act(fsm.REGULAR,
If(self.refresh_req,
fsm.next_state(fsm.REFRESH)
).Elif(cmdsource.stb,
If(has_openrow,
If(hit,
# NB: write-to-read specification is enforced by multiplexer
self.cmd.stb.eq(1),
cmdsource.ack.eq(self.cmd.ack),
self.cmd.is_read.eq(~cmdsource.we),
self.cmd.is_write.eq(cmdsource.we),
self.cmd.cas_n.eq(0),
self.cmd.we_n.eq(~cmdsource.we)
).Else(
fsm.next_state(fsm.PRECHARGE)
)
).Else(
fsm.next_state(fsm.ACTIVATE)
)
)
)
fsm.act(fsm.PRECHARGE,
# Notes:
# 1. we are presenting the column address, A10 is always low
# 2. since we always go to the ACTIVATE state, we do not need
# to assert track_close.
If(precharge_ok,
self.cmd.stb.eq(1),
If(self.cmd.ack, fsm.next_state(fsm.TRP)),
self.cmd.ras_n.eq(0),
self.cmd.we_n.eq(0)
)
)
fsm.act(fsm.ACTIVATE,
s_row_adr.eq(1),
track_open.eq(1),
self.cmd.stb.eq(1),
If(self.cmd.ack, fsm.next_state(fsm.TRCD)),
self.cmd.ras_n.eq(0)
)
fsm.act(fsm.REFRESH,
self.refresh_gnt.eq(precharge_ok),
track_close.eq(1),
If(~self.refresh_req, fsm.next_state(fsm.REGULAR))
)
