build/yosys_wrapper: a Yosys wrapper

litex/build/yosys_wrapper.py

@@ -0,0 +1,136 @@
+#
+# This file is part of LiteX.
+#
+# Copyright (c) 2022 Gwenhael Goavec-Merou <gwenhael.goavec-merou@trabucayre.com>
+# SPDX-License-Identifier: BSD-2-Clause
+
+
+from litex.build import tools
+
+
+class YosysWrapper():
+    """
+    YosysWrapper synthesis wrapper
+    """
+
+    def __init__(self, platform, build_name, target="", output_name="",
+            template=[], yosys_opts="",
+            yosys_cmds=[],
+            synth_format="json",
+            **kwargs):
+        """
+        Parameters
+        ==========
+        platform : GenericPlatform subclass
+            current platform.
+        build_name : str
+            gateware name.
+        target: str
+            target model (ice40, ecp5, nexus, ...).
+        output_name: str
+            output name if different to build_name [optional]
+        template: str
+            yosys template to use instead of default.
+        yosys_opts : str
+            Yosys options to use for synth_xxx
+        yosys_cmds : list
+            optionals commands called before synth_xxx
+        synth_format : str
+            Yosys ouptput format
+        kwargs: dict
+            list of key/value for yosys_opts [optional]
+        """
+
+        assert platform != ""
+        assert build_name != ""
+        assert target != ""
+        assert synth_format != ""
+
+        self._template = self._default_template if template == [] else template
+        self._output_name = build_name if output_name == "" else output_name
+
+        self._platform = platform
+        self._build_name = build_name
+        self._synth_format = synth_format
+        self._yosys_opts = yosys_opts
+        self._yosys_cmds = yosys_cmds
+
+        self._target=target
+
+        for key,value in kwargs.items():
+            key = key.replace("_","-")
+            if isinstance(value, bool):
+                self._yosys_opts += f"-{key} " if value else ""
+            else:
+                self._yosys_opts += f"-{key} {value} "
+
+    def _import_sources(self):
+        """built a list of sources to read
+        Return
+        ======
+            a string containing all read_xxx lines
+        """
+        includes = ""
+        reads = []
+        for path in self._platform.verilog_include_paths:
+            includes += " -I" + path
+        for filename, language, library, *copy in self._platform.sources:
+            # yosys has no such function read_systemverilog
+            if language == "systemverilog":
+                language = "verilog -sv"
+            reads.append(f"read_{language}{includes} {filename}")
+        return "\n".join(reads)
+
+    _default_template = [
+        "verilog_defaults -push",
+        "verilog_defaults -add -defer",
+        "{read_files}",
+        "verilog_defaults -pop",
+        "attrmap -tocase keep -imap keep=\"true\" keep=1 -imap keep=\"false\" keep=0 -remove keep=0",
+        "{yosys_cmds}",
+        "synth_{target} {synth_opts} -top {build_name}",
+        "write_{write_fmt} {write_opts} {output_name}.{synth_fmt}",
+    ]
+
+    def build_script(self):
+        """fill and write ys script.
+        """
+        read_files = self._import_sources()
+
+        format_dict = {
+            "build_name"  : self._build_name,
+            "read_files"  : read_files,
+            "synth_opts"  : self._yosys_opts,
+            "target"      : self._target,
+            "synth_fmt"   : self._synth_format,
+            "write_fmt"   : "verilog" if self._synth_format[0] == "v" else self._synth_format,
+            "write_opts"  : "-pvector bra -attrprop" if self._synth_format == "edif" else "",
+            "output_name" : self._output_name,
+        }
+
+        yosys_cmds = [l.format(**format_dict) for l in self._yosys_cmds]
+        format_dict["yosys_cmds"] = "\n".join(yosys_cmds)
+
+        ys = [l.format(**format_dict) for l in self._template]
+
+        tools.write_to_file(self._build_name + ".ys", "\n".join(ys))
+
+    def get_yosys_call(self, target="script"):
+        """built the script command or Makefile rule + command
+
+        Parameters
+        ==========
+        target : str
+            selects if it's a script command or a Makefile rule to be returned
+
+        Returns
+        =======
+        str containing instruction and/or rule
+        """
+        base_cmd = f"yosys -l {self._build_name}.rpt {self._build_name}.ys\n"
+        if target == "makefile":
+            return f"{self._build_name}.{self._synth_format}:\n\t" + base_cmd
+        elif target == "script":
+            return base_cmd
+        else:
+            raise ValueError("Invalid script type")