diff options
Diffstat (limited to 'qemu/roms/seabios/scripts/buildrom.py')
-rwxr-xr-x | qemu/roms/seabios/scripts/buildrom.py | 56 |
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() |