1#!/usr/bin/env python
2# Script to check a bios image and report info on it.
3#
4# Copyright (C) 2008  Kevin O'Connor <kevin@koconnor.net>
5#
6# This file may be distributed under the terms of the GNU GPLv3 license.
7
8import sys, struct
9import layoutrom, buildrom
10
11from python23compat import as_bytes
12
13def subst(data, offset, new):
14    return data[:offset] + new + data[offset + len(new):]
15
16def checksum(data, start, size, csum):
17    sumbyte = buildrom.checksum(data[start:start+size])
18    return subst(data, start+csum, sumbyte)
19
20def main():
21    # Get args
22    objinfo, finalsize, rawfile, outfile = sys.argv[1:]
23
24    # Read in symbols
25    objinfofile = open(objinfo, 'r')
26    symbols = layoutrom.parseObjDump(objinfofile, 'in')[1]
27
28    # Read in raw file
29    f = open(rawfile, 'rb')
30    rawdata = f.read()
31    f.close()
32    datasize = len(rawdata)
33    finalsize = int(finalsize) * 1024
34    if finalsize == 0:
35        finalsize = 64*1024
36        if datasize > 64*1024:
37            finalsize = 128*1024
38            if datasize > 128*1024:
39                finalsize = 256*1024
40    if datasize > finalsize:
41        print("Error!  ROM doesn't fit (%d > %d)" % (datasize, finalsize))
42        print("   You have to either increase the size (CONFIG_ROM_SIZE)")
43        print("   or turn off some features (such as hardware support not")
44        print("   needed) to make it fit.  Trying a more recent gcc version")
45        print("   might work too.")
46        sys.exit(1)
47
48    # Sanity checks
49    start = symbols['code32flat_start'].offset
50    end = symbols['code32flat_end'].offset
51    expend = layoutrom.BUILD_BIOS_ADDR + layoutrom.BUILD_BIOS_SIZE
52    if end != expend:
53        print("Error!  Code does not end at 0x%x (got 0x%x)" % (
54            expend, end))
55        sys.exit(1)
56    if datasize > finalsize:
57        print("Error!  Code is too big (0x%x vs 0x%x)" % (
58            datasize, finalsize))
59        sys.exit(1)
60    expdatasize = end - start
61    if datasize != expdatasize:
62        print("Error!  Unknown extra data (0x%x vs 0x%x)" % (
63            datasize, expdatasize))
64        sys.exit(1)
65
66    # Fix up CSM Compatibility16 table
67    if 'csm_compat_table' in symbols and 'entry_csm' in symbols:
68        # Field offsets within EFI_COMPATIBILITY16_TABLE
69        ENTRY_FIELD_OFS = 14 # Compatibility16CallOffset (UINT16)
70        SIZE_FIELD_OFS = 5   # TableLength (UINT8)
71        CSUM_FIELD_OFS = 4   # TableChecksum (UINT8)
72
73        tableofs = symbols['csm_compat_table'].offset - symbols['code32flat_start'].offset
74        entry_addr = symbols['entry_csm'].offset - layoutrom.BUILD_BIOS_ADDR
75        entry_addr = struct.pack('<H', entry_addr)
76        rawdata = subst(rawdata, tableofs+ENTRY_FIELD_OFS, entry_addr)
77
78        tsfield = tableofs+SIZE_FIELD_OFS
79        tablesize = ord(rawdata[tsfield:tsfield+1])
80        rawdata = checksum(rawdata, tableofs, tablesize, CSUM_FIELD_OFS)
81
82    # Print statistics
83    runtimesize = end - symbols['code32init_end'].offset
84    print("Total size: %d  Fixed: %d  Free: %d (used %.1f%% of %dKiB rom)" % (
85        datasize, runtimesize, finalsize - datasize
86        , (datasize / float(finalsize)) * 100.0
87        , int(finalsize / 1024)))
88
89    # Write final file
90    f = open(outfile, 'wb')
91    f.write((as_bytes("\0") * (finalsize - datasize)) + rawdata)
92    f.close()
93
94if __name__ == '__main__':
95    main()
96