util/cavium: Add tool to convert devicetree blobs

Convert Cavium's BDK devicetree blob to a static C file.

The resulting file must be included in mainboard folder to provide
board specific configuration values to BDK functions.

Example call:
python devicetree_convert.py --in sff8104.dtb --out bdk_devicetree.c

Change-Id: I76a5588aefe4f680228eca46a0e4dba7e695931c
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Reviewed-on: https://review.coreboot.org/26228
Reviewed-by: David Hendricks <david.hendricks@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

util/cavium/devicetree_convert.py

@@ -0,0 +1,55 @@
+#!/usr/bin/python
+
+# devicetree_convert Tool to convert a DTB to a static C file
+# Copyright (C) 2018 Facebook Inc.
+#
+# This program 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.
+#
+# This program 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.
+#
+
+from pyfdt.pyfdt import FdtBlobParse
+import argparse
+
+parser = argparse.ArgumentParser(description='Cavium DTB to C converter')
+parser.add_argument('--indtb', help='Compiled devicetree blob to parse')
+parser.add_argument('--out', help='The file to write')
+parser.add_argument('--verbose', help='Be verbose', action='store_true', default=False)
+args = parser.parse_args()
+
+outfile = None
+if args.out is not None:
+    outfile = open(args.out, 'w')
+    outfile.write("// This file is part of the coreboot project.\n")
+    outfile.write("// This file is automatically generated.\n")
+    outfile.write("// DO NOT EDIT BY HAND.\n\n")
+    outfile.write("#include <bdk-devicetree.h>\n\n")
+    outfile.write("const struct bdk_devicetree_key_value devtree[] = {\n")
+
+with open(args.indtb) as infile:
+    dtb = FdtBlobParse(infile)
+    fdt = dtb.to_fdt()
+    for (path, node) in fdt.resolve_path('/cavium,bdk').walk():
+        if "/" in path:
+            path = path.replace("/", "")
+        if len(node) == 1:
+            for i in node:
+                if type(i) is not unicode:
+                    print "%s: Type is not string" % path
+                    continue
+                if args.verbose:
+                    print "%s = %s" % (path, i)
+                if outfile is not None:
+                    outfile.write("{\"%s\", \"%s\"},\n" % (path, i))
+        else:
+            print "%s: Arrays aren't supported" % path
+
+if outfile is not None:
+    outfile.write("{0, 0},\n")
+    outfile.write("};\n")