litex/migen/bus/wishbone2csr.py

24 lines
642 B
Python

from migen.bus import wishbone
from migen.bus import csr
from migen.fhdl.structure import *
from migen.corelogic.misc import timeline
class WB2CSR:
def __init__(self):
self.wishbone = wishbone.Interface()
self.csr = csr.Interface()
def get_fragment(self):
sync = [
self.csr.we.eq(0),
self.csr.dat_w.eq(self.wishbone.dat_w[:8]),
self.csr.adr.eq(self.wishbone.adr[:14]),
self.wishbone.dat_r.eq(self.csr.dat_r)
]
sync += timeline(self.wishbone.cyc & self.wishbone.stb, [
(1, [self.csr.we.eq(self.wishbone.we)]),
(2, [self.wishbone.ack.eq(1)]),
(3, [self.wishbone.ack.eq(0)])
])
return Fragment(sync=sync)