--- /dev/null
+#!/usr/bin/env python3
+#
+# SPDX-License-Identifier: LGPLv3+
+# Copyright (C) 2020-2022 Raptor Engineering, LLC <support@raptorengineering.com>
+# Copyright (C) 2022 Luke Kenneth Casson Leighton <lkcl@lkcl.net>
+# Sponsored by NLnet and NGI POINTER under EU Grants 871528 and 957073
+# Part of the Libre-SOC Project.
+#
+# this is a wrapper around the opencores verilog tercel module
+
+from nmigen import (Elaboratable, Cat, Module, Signal, ClockSignal, Instance,
+ ResetSignal)
+
+from nmigen_soc.wishbone.bus import Interface
+from nmigen_soc.memory import MemoryMap
+from nmigen.utils import log2_int
+from nmigen.cli import rtlil, verilog
+import os
+
+__all__ = ["Tercel"]
+
+
+class Tercel(Elaboratable):
+ """Tercel SPI controller from Raptor Engineering, nmigen wrapper. remember to call
+ Tercel.add_verilog_source
+ """
+
+ def __init__(self, bus=None, cfg_bus=None, features=None, name=None,
+ data_width=32, spi_region_addr_width=28, pins=None,
+ clk_freq=None,
+ lattice_ecp5_usrmclk=False):
+ if name is not None:
+ # convention: give the name in the format "name_number"
+ self.idx = int(name.split("_")[-1])
+ else:
+ self.idx = 0
+ name = "spi_0"
+ self.granularity = 8
+ self.data_width = data_width
+ self.dsize = log2_int(self.data_width//self.granularity)
+
+ # set up the wishbone busses
+ if features is None:
+ features = frozenset()
+ if bus is None:
+ bus = Interface(addr_width=spi_region_addr_width,
+ data_width=data_width,
+ features=features,
+ granularity=8,
+ name=name+"_wb_%d_0" % self.idx)
+ if cfg_bus is None:
+ cfg_bus = Interface(addr_width=6,
+ data_width=data_width,
+ features=features,
+ granularity=8,
+ name=name+"_wb_%d_1" % self.idx)
+ self.bus = bus
+ assert len(self.bus.dat_r) == data_width, \
+ "bus width must be %d" % data_width
+ self.cfg_bus = cfg_bus
+ assert len(self.cfg_bus.dat_r) == data_width, \
+ "bus width must be %d" % data_width
+
+ mmap = MemoryMap(addr_width=spi_region_addr_width+self.dsize,
+ data_width=self.granularity)
+ cfg_mmap = MemoryMap(addr_width=6+self.dsize,
+ data_width=self.granularity)
+
+ self.bus.memory_map = mmap
+ self.cfg_bus.memory_map = cfg_mmap
+
+ # QSPI signals
+ self.dq_out = Signal(4) # Data
+ self.dq_direction = Signal(4)
+ self.dq_in = Signal(4)
+ self.cs_n_out = Signal() # Slave select
+ self.spi_clk = Signal() # Clock
+
+ # pins resource
+ self.pins = pins
+
+ @classmethod
+ def add_verilog_source(cls, verilog_src_dir, platform):
+ # add each of the verilog sources, needed for when doing platform.build
+ for fname in ['wishbone_spi_master.v', 'phy.v']:
+ # prepend the src directory to each filename, add its contents
+ fullname = os.path.join(verilog_src_dir, fname)
+ with open(fullname) as f:
+ platform.add_file(fullname, f)
+
+ def elaborate(self, platform):
+ m = Module()
+ comb = m.d.comb
+
+ # Calculate SPI flash address
+ spi_bus_adr = Signal(30)
+ self.comb += spi_bus_adr.eq(bus.adr - (adr_offset >> 2)) # wb address is in words, offset is in bytes
+
+ # create definition of external verilog Tercel code here, so that
+ # nmigen understands I/O directions (defined by i_ and o_ prefixes)
+ idx, bus = self.idx, self.bus
+ tercel = Instance("tercel_core",
+ # System parameters
+ i_sys_clk_freq = clk_freq,
+
+ # Clock/reset (use DomainRenamer if needed)
+ i_peripheral_clock=ClockSignal(),
+ i_peripheral_reset=ResetSignal(),
+
+ # SPI region Wishbone bus signals
+ i_wishbone_adr_i=spi_bus_adr,
+ i_wishbone_dat_i=bus.dat_w,
+ i_wishbone_sel_i=bus.sel,
+ o_wishbone_dat_o=bus.dat_r,
+ i_wishbone_we_i=bus.we,
+ i_wishbone_stb_i=bus.stb,
+ i_wishbone_cyc_i=bus.cyc,
+ o_wishbone_ack_o=bus.ack,
+
+ # Configuration region Wishbone bus signals
+ i_cfg_wishbone_adr_i=cfg_bus.adr,
+ i_cfg_wishbone_dat_i=cfg_bus.dat_w,
+ i_cfg_wishbone_sel_i=cfg_bus.sel,
+ o_cfg_wishbone_dat_o=cfg_bus.dat_r,
+ i_cfg_wishbone_we_i=cfg_bus.we,
+ i_cfg_wishbone_stb_i=cfg_bus.stb,
+ i_cfg_wishbone_cyc_i=cfg_bus.cyc,
+ o_cfg_wishbone_ack_o=cfg_bus.ack,
+
+ # QSPI signals
+ o_spi_d_out=self.dq_out,
+ o_spi_d_direction=self.dq_direction,
+ i_spi_d_in=self.dq_in,
+ o_spi_ss_n=self.cs_n_out,
+ o_spi_clock=self.spi_clk
+ );
+
+ m.submodules['tercel_%d' % self.idx] = uart
+
+ if self.pins is not None:
+ comb += self.pins.dq.o.eq(self.dq_out)
+ comb += self.pins.dq.oe.eq(self.dq_direction)
+ comb += self.pins.dq.oe.eq(self.dq_direction)
+ comb += self.pins.dq.o_clk.eq(ClockSignal())
+ comb += self.dq_in.eq(self.pins.dq.i)
+ comb += self.pins.dq.i_clk.eq(ClockSignal())
+ comb += self.pins.cs_n.eq(self.cs_n_out)
+ if lattice_ecp5_usrmclk:
+ self.specials += Instance("USRMCLK",
+ i_USRMCLKI = self.spi_clk,
+ i_USRMCLKTS = 0
+ )
+ else:
+ self.comb += pads.clk.eq(self.spi_clk)
+
+ return m
+
+
+def create_ilang(dut, ports, test_name):
+ vl = rtlil.convert(dut, name=test_name, ports=ports)
+ with open("%s.il" % test_name, "w") as f:
+ f.write(vl)
+
+def create_verilog(dut, ports, test_name):
+ vl = verilog.convert(dut, name=test_name, ports=ports)
+ with open("%s.v" % test_name, "w") as f:
+ f.write(vl)
+
+
+if __name__ == "__main__":
+ tercel = Tercel(name="spi_0", data_width=32)
+ create_ilang(tercel, [tercel.bus.cyc, tercel.bus.stb, tercel.bus.ack,
+ tercel.bus.dat_r, tercel.bus.dat_w, tercel.bus.adr,
+ tercel.bus.we, tercel.bus.sel,
+ tercel.cfg_bus.cyc, tercel.cfg_bus.stb, tercel.cfg_bus.ack,
+ tercel.cfg_bus.dat_r, tercel.cfg_bus.dat_w, tercel.cfg_bus.adr,
+ tercel.cfg_bus.we, tercel.cfg_bus.sel,
+ tercel.dq_out, tercel.dq_direction, tercel.dq_in,
+ tercel.cs_n_out, tercel.spi_clk
+ ], "spi_0")
+