litex/migen/bus/wishbone2csr.py

23 lines
738 B
Python

from migen.fhdl import structure as f
from migen.corelogic import timeline
from . import wishbone
from . import csr
class Inst():
def __init__(self):
self.wishbone = wishbone.Slave("to_csr")
self.csr = csr.Master("from_wishbone")
self.timeline = timeline.Inst(self.wishbone.cyc_i & self.wishbone.stb_i,
[(1, [f.Assign(self.csr.we_o, self.wishbone.we_i)]),
(2, [f.Assign(self.wishbone.ack_o, 1)]),
(3, [f.Assign(self.wishbone.ack_o, 0)])])
def GetFragment(self):
sync = [
f.Assign(self.csr.we_o, 0),
f.Assign(self.csr.d_o, self.wishbone.dat_i),
f.Assign(self.csr.a_o, self.wishbone.adr_i[2:16]),
f.Assign(self.wishbone.dat_o, self.csr.d_i)
]
return f.Fragment(sync=sync) + self.timeline.GetFragment()