Port IceStorm backend from Migen.

litex/build/lattice/icestorm.py

@@ -0,0 +1,148 @@
+# This file is Copyright (c) 2017 William D. Jones <thor0505@comcast.net>
+# License: BSD
+
+import os
+import sys
+import subprocess
+
+from litex.gen.fhdl.structure import _Fragment
+
+from litex.build.generic_platform import *
+from litex.build import tools
+
+
+def _format_constraint(c):
+    pass
+
+
+def _format_pcf(signame, pin, others, resname):
+    return "set_io " + signame + " " + pin + "\n"
+
+
+def _build_pcf(named_sc, named_pc):
+    r = ""
+    for sig, pins, others, resname in named_sc:
+        if len(pins) > 1:
+            for i, p in enumerate(pins):
+                r += _format_pcf(sig + "[" + str(i) + "]", p, others, resname)
+        else:
+            r += _format_pcf(sig, pins[0], others, resname)
+    if named_pc:
+        r += "\n" + "\n\n".join(named_pc)
+    return r
+
+
+def _build_yosys(device, sources, vincpaths, build_name):
+    ys_contents = ""
+    incflags = ""
+    for path in vincpaths:
+        incflags += " -I" + path
+    for filename, language, library in sources:
+        ys_contents += "read_{}{} {}\n".format(language, incflags, filename)
+
+    ys_contents += """synth_ice40 -top top -blif {build_name}.blif""".format(
+        build_name=build_name)
+
+    ys_name = build_name + ".ys"
+    tools.write_to_file(ys_name, ys_contents)
+
+
+def _run_icestorm(build_name, source, yosys_opt, pnr_opt,
+                  icetime_opt, icepack_opt):
+    if sys.platform == "win32" or sys.platform == "cygwin":
+        source_cmd = "call "
+        script_ext = ".bat"
+        shell = ["cmd", "/c"]
+        build_script_contents = "@echo off\nrem Autogenerated by LiteX\n"
+        fail_stmt = " || exit /b"
+    else:
+        source_cmd = "source "
+        script_ext = ".sh"
+        shell = ["bash"]
+        build_script_contents = "# Autogenerated by LiteX\nset -e\n"
+        fail_stmt = ""
+
+    build_script_contents += """
+yosys {yosys_opt} -l {build_name}.rpt {build_name}.ys{fail_stmt}
+arachne-pnr {pnr_opt} -p {build_name}.pcf {build_name}.blif -o {build_name}.txt{fail_stmt}
+icetime {icetime_opt} -t -p {build_name}.pcf -r {build_name}.tim {build_name}.txt{fail_stmt}
+icepack {icepack_opt} {build_name}.txt {build_name}.bin{fail_stmt}
+"""
+    build_script_contents = build_script_contents.format(
+        build_name=build_name,
+        yosys_opt=yosys_opt, pnr_opt=pnr_opt, icepack_opt=icepack_opt,
+        icetime_opt=icetime_opt, fail_stmt=fail_stmt)
+    build_script_file = "build_" + build_name + script_ext
+    tools.write_to_file(build_script_file, build_script_contents,
+                        force_unix=False)
+    command = shell + [build_script_file]
+    r = subprocess.call(command)
+    if r != 0:
+        raise OSError("Subprocess failed")
+
+
+class LatticeIceStormToolchain:
+    def __init__(self):
+        self.yosys_opt = "-q"
+        self.pnr_opt = "-q"
+        self.icetime_opt = ""
+        self.icepack_opt = ""
+        self.freq_constraints = dict()
+
+    # platform.device should be of the form "ice40-{1k,8k}-{tq144, etc}""
+    def build(self, platform, fragment, build_dir="build", build_name="top",
+              run=True):
+        os.makedirs(build_dir, exist_ok=True)
+        cwd = os.getcwd()
+        os.chdir(build_dir)
+
+        if not isinstance(fragment, _Fragment):
+            fragment = fragment.get_fragment()
+        platform.finalize(fragment)
+
+        v_output = platform.get_verilog(fragment)
+        named_sc, named_pc = platform.resolve_signals(v_output.ns)
+        v_file = build_name + ".v"
+        v_output.write(v_file)
+        sources = platform.sources | {(v_file, "verilog", "work")}
+        _build_yosys(platform.device, sources, platform.verilog_include_paths,
+                     build_name)
+
+        tools.write_to_file(build_name + ".pcf",
+                            _build_pcf(named_sc, named_pc))
+        if run:
+            (family, size, package) = self.parse_device_string(platform.device)
+            pnr_opt = self.pnr_opt + " -d " + size + " -P " + package
+            # TODO: PNR will probably eventually support LP devices.
+            icetime_opt = self.icetime_opt + " -P " + package + \
+                " -d " + "hx" + size + " -c " + \
+                str(max(self.freq_constraints.values(), default=0.0))
+            _run_icestorm(build_name, False, self.yosys_opt, pnr_opt,
+                          icetime_opt, self.icepack_opt)
+
+        os.chdir(cwd)
+
+        return v_output.ns
+
+    def parse_device_string(self, device_str):
+        (family, size, package) = device_str.split("-")
+        if family not in ["ice40"]:
+            raise ValueError("Unknown device family")
+        if size not in ["1k", "8k"]:
+            raise ValueError("Invalid device size")
+        if package not in ["tq144", "ct256", "vq100"]:
+            raise ValueError("Invalid device package")
+        return (family, size, package)
+
+    # icetime can only handle a single global constraint. Pending more
+    # finely-tuned analysis features in arachne-pnr and IceStorm, save
+    # all the constraints in a dictionary and test against the fastest clk.
+    # Though imprecise, if the global design satisfies the fastest clock,
+    # we can be sure all other constraints are satisfied.
+    def add_period_constraint(self, platform, clk, period):
+        new_freq = 1000.0/period
+
+        if clk not in self.freq_constraints.keys():
+            self.freq_constraints[clk] = new_freq
+        else:
+            raise ConstraintError("Period constraint already added to signal.")

litex/build/lattice/platform.py

@@ -1,5 +1,5 @@
 from litex.build.generic_platform import GenericPlatform
-from litex.build.lattice import common, diamond
+from litex.build.lattice import common, diamond, icestorm
 
 
 class LatticePlatform(GenericPlatform):
@@ -9,6 +9,9 @@ class LatticePlatform(GenericPlatform):
         GenericPlatform.__init__(self, *args, **kwargs)
         if toolchain == "diamond":
             self.toolchain = diamond.LatticeDiamondToolchain()
+        elif toolchain == "icestorm":
+            self.bitstream_ext = ".bin"
+            self.toolchain = icestorm.LatticeIceStormToolchain()
         else:
             raise ValueError("Unknown toolchain")
 

litex/build/lattice/programmer.py

@@ -20,3 +20,24 @@ class LatticeProgrammer(GenericProgrammer):
         else:
             pgrcmr = 'pgrcmr'
         subprocess.call([pgrcmd, "-infile", xcf_file])
+
+
+class IceStormProgrammer(GenericProgrammer):
+    needs_bitreverse = False
+
+    def flash(self, address, bitstream_file):
+        subprocess.call(["iceprog", "-o", str(address), bitstream_file])
+
+    def load_bitstream(self, bitstream_file):
+        subprocess.call(["iceprog", "-S", bitstream_file])
+
+
+class IceBurnProgrammer(GenericProgrammer):
+    def __init__(self, iceburn_path):
+        GenericProgrammer.__init__(self)
+        self.iceburn = iceburn_path
+
+    needs_bitreverse = False
+
+    def load_bitstream(self, bitstream_file):
+        subprocess.call([self.iceburn, "-evw", bitstream_file])