from migen.fhdl.std import * from migen.bus import wishbone from misoclib import spiflash from misoclib.gensoc import GenSoC class SimpleSoC(GenSoC): default_platform = "papilio_pro" def __init__(self, platform): GenSoC.__init__(self, platform, clk_freq=32*1000000, cpu_reset_address=0x60000) # We can't use reset_less as LM32 does require a reset signal self.clock_domains.cd_sys = ClockDomain() self.comb += self.cd_sys.clk.eq(platform.request("clk32")) self.specials += Instance("FD", p_INIT=1, i_D=0, o_Q=self.cd_sys.rst, i_C=ClockSignal()) # BIOS is in SPI flash self.submodules.spiflash = spiflash.SpiFlash(platform.request("spiflash2x"), cmd=0xefef, cmd_width=16, addr_width=24, dummy=4) self.flash_boot_address = 0x70000 self.register_rom(self.spiflash.bus) # TODO: use on-board SDRAM instead of block RAM sys_ram_size = 32*1024 self.submodules.sys_ram = wishbone.SRAM(sys_ram_size) self.add_wb_slave(lambda a: a[27:29] == 2, self.sys_ram.bus) self.add_cpu_memory_region("sdram", 0x40000000, sys_ram_size) default_subtarget = SimpleSoC