targets/simple.py

   1 from migen.fhdl.std import *
   2
   3 from misoclib import gpio, spiflash
   4 from misoclib.gensoc import GenSoC, IntegratedBIOS
   5
   6 class SimpleSoC(GenSoC, IntegratedBIOS):
   7         def __init__(self, platform):
   8                 GenSoC.__init__(self, platform,
   9                         clk_freq=32*1000000,
  10                         cpu_reset_address=0)
  11                 IntegratedBIOS.__init__(self)
  12
  13                 # We can't use reset_less as LM32 does require a reset signal
  14                 self.clock_domains.cd_sys = ClockDomain()
  15                 self.comb += self.cd_sys.clk.eq(platform.request("clk32"))
  16                 self.specials += Instance("FD", p_INIT=1, i_D=0, o_Q=self.cd_sys.rst, i_C=ClockSignal())
  17
  18                 self.submodules.leds = gpio.GPIOOut(platform.request("user_led"))
  19
  20                 # Map the SPI flash at 0xb0000000 for demo purposes. Later, we'll want to store the BIOS there.
  21                 self.submodules.spiflash = spiflash.SpiFlash(platform.request("spiflash2x"),
  22                         cmd=0xefef, cmd_width=16, addr_width=24, dummy=4)
  23                 self.add_wb_slave(lambda a: a[26:29] == 3, self.spiflash.bus)
  24
  25 def get_default_subtarget(platform):
  26         return SimpleSoC