def _split_mem(self, mem):
depths = [1 << i for i in range(log2_int(mem.depth, need_pow2=False))
if mem.depth & (1 << i)]
depths.reverse()
inits = None
if mem.init is not None:
inits = list(mem.init)
mems = []
for i, depth in enumerate(depths):
init = None
if inits is not None:
init = inits[:depth]
del inits[:depth]
name = "{}_part{}".format(mem.name_override, i)
mems.append(Memory(width=mem.width, depth=depth,
init=init, name=name))
ports = []
comb = []
sync = {}
for port in mem.ports:
p, c, s = self._split_port(port, mems)
ports += p
comb += c
sy = sync.setdefault(port.clock.cd, [])
sy += s
return mems + ports, comb, sync
def transform_fragment(self, i, f):
old_specials, f.specials = f.specials, set()
old_ports = set()
for old in old_specials:
if not isinstance(old, Memory):
f.specials.add(old)
continue
try:
log2_int(old.depth, need_pow2=True)
f.specials.add(old)
except ValueError:
new, comb, sync = self._split_mem(old)
old_ports |= set(old.ports)
f.specials.update(new)
f.comb += comb
for cd, sy in sync.items():
s = f.sync.setdefault(cd, [])
s += sy
f.specials -= old_ports
def __init__(self, width, depth):
super().__init__(width, depth)
###
depth_bits = log2_int(depth, True)
produce = ClockDomainsRenamer("write")(GrayCounter(depth_bits + 1))
consume = ClockDomainsRenamer("read")(GrayCounter(depth_bits + 1))
self.submodules += produce, consume
self.comb += [
produce.ce.eq(self.writable & self.we),
consume.ce.eq(self.readable & self.re)
]
produce_rdomain = Signal(depth_bits + 1)
self.specials += [
NoRetiming(produce.q),
MultiReg(produce.q, produce_rdomain, "read")
]
consume_wdomain = Signal(depth_bits + 1)
self.specials += [
NoRetiming(consume.q),
MultiReg(consume.q, consume_wdomain, "write")
]
if depth_bits == 1:
self.comb += self.writable.eq((produce.q[-1] == consume_wdomain[-1])
| (produce.q[-2] == consume_wdomain[-2]))
else:
self.comb += [
self.writable.eq((produce.q[-1] == consume_wdomain[-1])
| (produce.q[-2] == consume_wdomain[-2])
| (produce.q[:-2] != consume_wdomain[:-2]))
]
self.comb += self.readable.eq(consume.q != produce_rdomain)
storage = Memory(self.width, depth)
self.specials += storage
wrport = storage.get_port(write_capable=True, clock_domain="write")
self.specials += wrport
self.comb += [
wrport.adr.eq(produce.q_binary[:-1]),
wrport.dat_w.eq(self.din),
wrport.we.eq(produce.ce)
]
rdport = storage.get_port(clock_domain="read")
self.specials += rdport
self.comb += [
rdport.adr.eq(consume.q_next_binary[:-1]),
self.dout.eq(rdport.dat_r)
]
def __init__(self, width, depth):
super().__init__(width, depth)
###
depth_bits = log2_int(depth, True)
produce = ClockDomainsRenamer("write")(GrayCounter(depth_bits + 1))
consume = ClockDomainsRenamer("read")(GrayCounter(depth_bits + 1))
self.submodules += produce, consume
self.comb += [
produce.ce.eq(self.writable & self.we),
consume.ce.eq(self.readable & self.re)
]
produce_rdomain = Signal(depth_bits + 1)
produce.q.attr.add("no_retiming")
self.specials += MultiReg(produce.q, produce_rdomain, "read")
consume_wdomain = Signal(depth_bits + 1)
consume.q.attr.add("no_retiming")
self.specials += MultiReg(consume.q, consume_wdomain, "write")
if depth_bits == 1:
self.comb += self.writable.eq(
(produce.q[-1] == consume_wdomain[-1]) |
(produce.q[-2] == consume_wdomain[-2]))
else:
self.comb += [
self.writable.eq(
(produce.q[-1] == consume_wdomain[-1]) |
(produce.q[-2] == consume_wdomain[-2]) |
(produce.q[:-2] != consume_wdomain[:-2]))
]
self.comb += self.readable.eq(consume.q != produce_rdomain)
storage = Memory(self.width, depth)
self.specials += storage
wrport = storage.get_port(write_capable=True, clock_domain="write")
self.specials += wrport
self.comb += [
wrport.adr.eq(produce.q_binary[:-1]),
wrport.dat_w.eq(self.din),
wrport.we.eq(produce.ce)
]
rdport = storage.get_port(clock_domain="read")
self.specials += rdport
self.comb += [
rdport.adr.eq(consume.q_next_binary[:-1]),
self.dout.eq(rdport.dat_r)
]