diff --git a/litex_boards/targets/sipeed_tang_nano.py b/litex_boards/targets/sipeed_tang_nano.py index 3a97333..7804150 100755 --- a/litex_boards/targets/sipeed_tang_nano.py +++ b/litex_boards/targets/sipeed_tang_nano.py @@ -6,12 +6,37 @@ # Copyright (c) 2021 Florent Kermarrec # SPDX-License-Identifier: BSD-2-Clause +# Build/Use +# --------- +# 1) Update CH552 firmware: https://qiita.com/ciniml/items/05ac7fd2515ceed3f88d +# 2) Build/Load design: ./sipeed_tang_nano.py --csr-csv=csr.csv --build --load +# 3) Patch litex_server (CH552 firmware seems to require receiving a few bytes before +# operating correctly...): +#diff --git a/litex/tools/remote/comm_uart.py b/litex/tools/remote/comm_uart.py +#index bb124fb3..d5a075fd 100644 +#--- a/litex/tools/remote/comm_uart.py +#+++ b/litex/tools/remote/comm_uart.py +#@@ -29,6 +29,8 @@ class CommUART(CSRBuilder): +# if hasattr(self, "port"): +# return +# self.port.open() +#+ for i in range(256): +#+ self.port.write(0) +# +# def close(self): +# if not hasattr(self, "port"): +# 4) Start litex_server at 1MBps (CH552 does not seem to work at traditional baudrates...): +# litex_server --uart --uart-port=/dev/ttyUSBX --uart-baudrate=1000000 +# 5) Test UARTBone ex: litex_cli --regs + + import os import argparse from migen import * from migen.genlib.resetsync import AsyncResetSynchronizer +from litex.soc.cores.clock.gowin_gw1n import GW1NPLL from litex.soc.integration.soc_core import * from litex.soc.integration.builder import * from litex.soc.cores.led import LedChaser @@ -27,36 +52,33 @@ class _CRG(Module): # # # - # Clk / Rst + # Clk / Rst. clk24 = platform.request("clk24") rst_n = platform.request("user_btn", 0) - self.comb += self.cd_sys.clk.eq(clk24) - self.specials += AsyncResetSynchronizer(self.cd_sys, ~rst_n) + + # PLL. + self.submodules.pll = pll = GW1NPLL(device="GW1N-1") + self.comb += pll.reset.eq(~rst_n) + pll.register_clkin(clk24, 24e6) + pll.create_clkout(self.cd_sys, sys_clk_freq) # BaseSoC ------------------------------------------------------------------------------------------ -class BaseSoC(SoCCore): - def __init__(self, sys_clk_freq=int(24e6), with_led_chaser=True, **kwargs): +class BaseSoC(SoCMini): + def __init__(self, sys_clk_freq=int(48e6), with_led_chaser=True, **kwargs): platform = tang_nano.Platform() - - # Disable CPU/UART for now. - kwargs["cpu_type"] = None - kwargs["with_uart"] = False - - # UART loopback. - serial_pads = platform.request("serial") - self.comb += serial_pads.tx.eq(serial_pads.rx) - - # SoCCore ---------------------------------------------------------------------------------- - SoCCore.__init__(self, platform, sys_clk_freq, + # SoCMini ---------------------------------------------------------------------------------- + SoCMini.__init__(self, platform, sys_clk_freq, ident = "LiteX SoC on Tang Nano", - ident_version = True, - **kwargs) + ident_version = True) # CRG -------------------------------------------------------------------------------------- self.submodules.crg = _CRG(platform, sys_clk_freq) + # UARTBone --------------------------------------------------------------------------------- + self.add_uartbone(baudrate=int(1e6)) # CH552 firmware does not support traditional baudrates. + # Leds ------------------------------------------------------------------------------------- if with_led_chaser: self.submodules.leds = LedChaser( @@ -70,7 +92,7 @@ def main(): parser.add_argument("--build", action="store_true", help="Build bitstream") parser.add_argument("--load", action="store_true", help="Load bitstream") parser.add_argument("--flash", action="store_true", help="Flash Bitstream") - parser.add_argument("--sys-clk-freq",default=24e6, help="System clock frequency (default: 24MHz)") + parser.add_argument("--sys-clk-freq",default=48e6, help="System clock frequency (default: 48MHz)") builder_args(parser) soc_core_args(parser) args = parser.parse_args()