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-rwxr-xr-xqemu/roms/seabios/scripts/buildrom.py56
1 files changed, 56 insertions, 0 deletions
diff --git a/qemu/roms/seabios/scripts/buildrom.py b/qemu/roms/seabios/scripts/buildrom.py
new file mode 100755
index 000000000..0499049c3
--- /dev/null
+++ b/qemu/roms/seabios/scripts/buildrom.py
@@ -0,0 +1,56 @@
+#!/usr/bin/env python
+# Fill in checksum/size of an option rom, and pad it to proper length.
+#
+# Copyright (C) 2009 Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+
+import sys, struct
+
+from python23compat import as_bytes
+
+def alignpos(pos, alignbytes):
+ mask = alignbytes - 1
+ return (pos + mask) & ~mask
+
+def checksum(data):
+ if (sys.version_info > (3, 0)):
+ cksum = sum(data)
+ else:
+ cksum = sum(map(ord, data))
+ return struct.pack('<B', (0x100 - cksum) & 0xff)
+
+def main():
+ inname = sys.argv[1]
+ outname = sys.argv[2]
+
+ # Read data in
+ f = open(inname, 'rb')
+ data = f.read()
+ f.close()
+ count = len(data)
+
+ # Pad to a 512 byte boundary
+ data += as_bytes("\0") * (alignpos(count, 512) - count)
+ count = len(data)
+
+ # Check if a pci header is present
+ pcidata = ord(data[24:25]) + (ord(data[25:26]) << 8)
+ if pcidata != 0:
+ blocks = struct.pack('<H', int(count/512))
+ data = data[:pcidata + 16] + blocks + data[pcidata + 18:]
+
+ # Fill in size field; clear checksum field
+ blocks = struct.pack('<B', int(count/512))
+ data = data[:2] + blocks + data[3:6] + as_bytes("\0") + data[7:]
+
+ # Checksum rom
+ data = data[:6] + checksum(data) + data[7:]
+
+ # Write new rom
+ f = open(outname, 'wb')
+ f.write(data)
+ f.close()
+
+if __name__ == '__main__':
+ main()