litex/milkymist/m1crg/__init__.py

52 lines
1.4 KiB
Python

from fractions import Fraction
from migen.fhdl.structure import *
class M1CRG:
def __init__(self, infreq, outfreq1x):
self.clkin = Signal()
self.trigger_reset = Signal()
self.cd_sys = ClockDomain("sys")
self.cd_sys2x_270 = ClockDomain("sys2x_270")
self.cd_sys4x_wr = ClockDomain("sys4x_wr")
self.cd_sys4x_rd = ClockDomain("sys4x_rd")
self.cd_vga = ClockDomain("vga")
ratio = Fraction(outfreq1x)/Fraction(infreq)
in_period = float(Fraction(1000000000)/Fraction(infreq))
inst_items = [
Instance.Parameter("in_period", in_period),
Instance.Parameter("f_mult", ratio.numerator),
Instance.Parameter("f_div", ratio.denominator),
Instance.Input("clkin", self.clkin),
Instance.Input("trigger_reset", self.trigger_reset),
Instance.Output("sys_clk", self.cd_sys.clk),
Instance.Output("sys_rst", self.cd_sys.rst),
Instance.Output("clk2x_270", self.cd_sys2x_270.clk),
Instance.Output("clk4x_wr", self.cd_sys4x_wr.clk),
Instance.Output("clk4x_rd", self.cd_sys4x_rd.clk),
Instance.Output("vga_clk", self.cd_vga.clk)
]
for name in [
"ac97_rst_n",
"videoin_rst_n",
"flash_rst_n",
"clk4x_wr_strb",
"clk4x_rd_strb",
"eth_clk_pad",
"vga_clk_pad"
]:
s = Signal(name=name)
setattr(self, name, s)
inst_items.append(Instance.Output(name, s))
self._inst = Instance("m1crg", *inst_items)
def get_fragment(self):
return Fragment(instances=[self._inst])