bit2bin: add small bitstream conversion tool

artiq/frontend/bit2bin.py

@@ -0,0 +1,79 @@
+#!/usr/bin/env python3.5
+# Copyright 2014-2015 Robert Jordens <jordens@gmail.com>
+# after
+# https://github.com/mfischer/fpgadev-zynq/blob/master/top/python/bit_to_zynq_bin.py
+#
+# This file is part of redpid.
+#
+# redpid is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# redpid is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with redpid.  If not, see <http://www.gnu.org/licenses/>.
+
+import struct
+
+
+def flip32(data):
+    sl = struct.Struct("<I")
+    sb = struct.Struct(">I")
+    b = memoryview(data)
+    d = bytearray(len(data))
+    for offset in range(0, len(data), sl.size):
+         sb.pack_into(d, offset, *sl.unpack_from(b, offset))
+    return d
+
+
+def bit2bin(bit, bin, flip=False):
+    bitfile = open(bit, "rb")
+
+    l, = struct.unpack(">H", bitfile.read(2))
+    if l != 9:
+        raise ValueError("Missing <0009> header, not a bit file")
+
+    bitfile.read(l)
+    d = bitfile.read(*struct.unpack(">H", bitfile.read(2)))
+    if d != b"a":
+        raise ValueError("Missing <a> header, not a bit file")
+
+    d = bitfile.read(*struct.unpack(">H", bitfile.read(2)))
+    print("Design name:", d)
+
+    while True:
+        key = bitfile.read(1)
+        if not key:
+            break
+        if key in b"bcd":
+            d = bitfile.read(*struct.unpack(">H", bitfile.read(2)))
+            name = {b"b": "Partname", b"c": "Date", b"d": "Time"}[key]
+            print(name, d)
+        elif key == b"e":
+            l, = struct.unpack(">I", bitfile.read(4))
+            print("found binary data length:", l)
+            d = bitfile.read(l)
+            if flip:
+                d = flip32(d)
+            open(bin, "wb").write(d)
+        else:
+            d = bitfile.read(*struct.unpack(">H", bitfile.read(2)))
+            print("Unexpected key: ", key, d)
+
+
+if __name__ == "__main__":
+    import argparse
+    parser = argparse.ArgumentParser(
+            description="Convert FPGA bit files to raw bin format suitable for flashing")
+    parser.add_argument("-f", "--flip", dest="flip", action="store_true",
+            default=False, help="Flip 32-bit endianess (needed for Zynq)")
+    parser.add_argument("bitfile", help="Input bit file name")
+    parser.add_argument("binfile", help="Output bin file name")
+    args = parser.parse_args()
+
+    bit2bin(args.bitfile, args.binfile, args.flip)