litex/misoclib/dfii/__init__.py

58 lines
1.9 KiB
Python

from migen.fhdl.std import *
from migen.bus import dfi
from migen.bank.description import *
class PhaseInjector(Module, AutoCSR):
def __init__(self, phase):
self._command = CSRStorage(6) # cs, we, cas, ras, wren, rden
self._command_issue = CSR()
self._address = CSRStorage(flen(phase.address))
self._baddress = CSRStorage(flen(phase.bank))
self._wrdata = CSRStorage(flen(phase.wrdata))
self._rddata = CSRStatus(flen(phase.rddata))
###
self.comb += [
If(self._command_issue.re,
phase.cs_n.eq(~self._command.storage[0]),
phase.we_n.eq(~self._command.storage[1]),
phase.cas_n.eq(~self._command.storage[2]),
phase.ras_n.eq(~self._command.storage[3])
).Else(
phase.cs_n.eq(1),
phase.we_n.eq(1),
phase.cas_n.eq(1),
phase.ras_n.eq(1)
),
phase.address.eq(self._address.storage),
phase.bank.eq(self._baddress.storage),
phase.wrdata_en.eq(self._command_issue.re & self._command.storage[4]),
phase.rddata_en.eq(self._command_issue.re & self._command.storage[5]),
phase.wrdata.eq(self._wrdata.storage),
phase.wrdata_mask.eq(0)
]
self.sync += If(phase.rddata_valid, self._rddata.status.eq(phase.rddata))
class DFIInjector(Module, AutoCSR):
def __init__(self, a, ba, d, nphases=1):
inti = dfi.Interface(a, ba, d, nphases)
self.slave = dfi.Interface(a, ba, d, nphases)
self.master = dfi.Interface(a, ba, d, nphases)
self._control = CSRStorage(4) # sel, cke, odt, reset_n
for n, phase in enumerate(inti.phases):
setattr(self.submodules, "pi" + str(n), PhaseInjector(phase))
###
self.comb += If(self._control.storage[0],
self.slave.connect(self.master)
).Else(
inti.connect(self.master)
)
self.comb += [phase.cke.eq(self._control.storage[1]) for phase in inti.phases]
self.comb += [phase.odt.eq(self._control.storage[2]) for phase in inti.phases if hasattr(phase, "odt")]
self.comb += [phase.reset_n.eq(self._control.storage[3]) for phase in inti.phases if hasattr(phase, "reset_n")]