scripts/mkknlimg

   1 #!/usr/bin/env perl
   2 # ----------------------------------------------------------------------
   3 # mkknlimg by Phil Elwell for Raspberry Pi
   4 # based on extract-ikconfig by Dick Streefland
   5 #
   6 # (c) 2009,2010 Dick Streefland <dick@streefland.net>
   7 # (c) 2014,2015 Raspberry Pi (Trading) Limited <info@raspberrypi.org>
   8 #
   9 # Licensed under the terms of the GNU General Public License.
  10 # ----------------------------------------------------------------------
  11
  12 use strict;
  13 use warnings;
  14 use integer;
  15
  16 use constant FLAG_PI   => 0x01;
  17 use constant FLAG_DTOK => 0x02;
  18 use constant FLAG_DDTK => 0x04;
  19 use constant FLAG_270X => 0x08;
  20 use constant FLAG_283X => 0x10;
  21
  22 my $trailer_magic = 'RPTL';
  23
  24 my $tmpfile1 = "/tmp/mkknlimg_$$.1";
  25 my $tmpfile2 = "/tmp/mkknlimg_$$.2";
  26
  27 my $dtok = 0;
  28 my $ddtk = 0;
  29 my $is_270x = 0;
  30 my $is_283x = 0;
  31
  32 while (@ARGV && ($ARGV[0] =~ /^-/))
  33 {
  34     my $arg = shift(@ARGV);
  35     if ($arg eq '--dtok')
  36     {
  37         $dtok = 1;
  38     }
  39     elsif ($arg eq '--ddtk')
  40     {
  41         $ddtk = 1;
  42     }
  43     elsif ($arg eq '--270x')
  44     {
  45         $is_270x = 1;
  46     }
  47     elsif ($arg eq '--283x')
  48     {
  49         $is_283x = 1;
  50     }
  51     else
  52     {
  53         print ("* Unknown option '$arg'\n");
  54         usage();
  55     }
  56 }
  57
  58 usage() if (@ARGV != 2);
  59
  60 my $kernel_file = $ARGV[0];
  61 my $out_file = $ARGV[1];
  62
  63 if (! -r $kernel_file)
  64 {
  65     print ("* File '$kernel_file' not found\n");
  66     usage();
  67 }
  68
  69 my $wanted_strings =
  70 {
  71         'bcm2708_fb' => FLAG_PI,
  72         'brcm,bcm2835-mmc' => FLAG_PI,
  73         'brcm,bcm2835-sdhost' => FLAG_PI,
  74         'brcm,bcm2708-pinctrl' => FLAG_PI | FLAG_DTOK,
  75         'brcm,bcm2835-gpio' => FLAG_PI | FLAG_DTOK,
  76         'brcm,bcm2708' => FLAG_PI | FLAG_DTOK | FLAG_270X,
  77         'brcm,bcm2709' => FLAG_PI | FLAG_DTOK | FLAG_270X,
  78         'brcm,bcm2835' => FLAG_PI | FLAG_DTOK | FLAG_283X,
  79         'brcm,bcm2836' => FLAG_PI | FLAG_DTOK | FLAG_283X,
  80         'of_cfs_init' => FLAG_DTOK | FLAG_DDTK,
  81         'vc_cma_init' => FLAG_PI | FLAG_270X,
  82 };
  83
  84 my $res = try_extract($kernel_file, $tmpfile1);
  85 $res ||= try_decompress('\037\213\010', 'xy',    'gunzip', 0,
  86                         $kernel_file, $tmpfile1, $tmpfile2);
  87 $res ||= try_decompress('\3757zXZ\000', 'abcde', 'unxz --single-stream', -1,
  88                         $kernel_file, $tmpfile1, $tmpfile2);
  89 $res ||= try_decompress('BZh',          'xy',    'bunzip2', 0,
  90                         $kernel_file, $tmpfile1, $tmpfile2);
  91 $res ||= try_decompress('\135\0\0\0',   'xxx',   'unlzma', 0,
  92                         $kernel_file, $tmpfile1, $tmpfile2);
  93 $res ||= try_decompress('\211\114\132', 'xy',    'lzop -d', 0,
  94                         $kernel_file, $tmpfile1, $tmpfile2);
  95 $res ||= try_decompress('\002\041\114\030', 'xy',    'lz4 -d', 1,
  96                         $kernel_file, $tmpfile1, $tmpfile2);
  97
  98 my $append_trailer;
  99 my $trailer;
 100 my $kver = '?';
 101
 102 $append_trailer = 1;
 103
 104 if ($res)
 105 {
 106     $kver = $res->{'kver'} || '?';
 107     my $flags = $res->{'flags'};
 108     print("Version: $kver\n");
 109
 110     if ($flags & FLAG_PI)
 111     {
 112         $dtok ||= ($flags & FLAG_DTOK) != 0;
 113         $is_270x ||= ($flags & FLAG_270X) != 0;
 114         $is_283x ||= ($flags & FLAG_283X) != 0;
 115         $ddtk ||= ($flags & FLAG_DDTK) != 0;
 116     }
 117     else
 118     {
 119         print ("* This doesn't look like a Raspberry Pi kernel.\n");
 120     }
 121 }
 122 elsif (!$dtok)
 123 {
 124     print ("* Is this a valid kernel?\n");
 125 }
 126
 127 if ($append_trailer)
 128 {
 129     printf("DT: %s\n", $dtok ? "y" : "n");
 130     printf("DDT: %s\n", $ddtk ? "y" : "n");
 131     printf("270x: %s\n", $is_270x ? "y" : "n");
 132     printf("283x: %s\n", $is_283x ? "y" : "n");
 133
 134     my @atoms;
 135
 136     push @atoms, [ $trailer_magic, pack('V', 0) ];
 137     push @atoms, [ 'KVer', $kver ];
 138     push @atoms, [ 'DTOK', pack('V', $dtok) ];
 139     push @atoms, [ 'DDTK', pack('V', $ddtk) ];
 140     push @atoms, [ '270X', pack('V', $is_270x) ];
 141     push @atoms, [ '283X', pack('V', $is_283x) ];
 142     push @atoms, [ '283x', pack('V', $is_283x && !$is_270x) ];
 143
 144     $trailer = pack_trailer(\@atoms);
 145     $atoms[0]->[1] = pack('V', length($trailer));
 146
 147     $trailer = pack_trailer(\@atoms);
 148 }
 149
 150 my $ofh;
 151 my $total_len = 0;
 152
 153 if ($out_file eq $kernel_file)
 154 {
 155     die "* Failed to open '$out_file' for append\n"
 156         if (!open($ofh, '>>', $out_file));
 157     $total_len = tell($ofh);
 158 }
 159 else
 160 {
 161     die "* Failed to open '$kernel_file'\n"
 162         if (!open(my $ifh, '<', $kernel_file));
 163     die "* Failed to create '$out_file'\n"
 164         if (!open($ofh, '>', $out_file));
 165
 166     my $copybuf;
 167     while (1)
 168     {
 169         my $bytes = sysread($ifh, $copybuf, 64*1024);
 170         last if (!$bytes);
 171         syswrite($ofh, $copybuf, $bytes);
 172         $total_len += $bytes;
 173     }
 174     close($ifh);
 175 }
 176
 177 if ($trailer)
 178 {
 179     # Pad to word-alignment
 180     syswrite($ofh, "\x000\x000\x000", (-$total_len & 0x3));
 181     syswrite($ofh, $trailer);
 182 }
 183
 184 close($ofh);
 185
 186 exit($trailer ? 0 : 1);
 187
 188 END {
 189         unlink($tmpfile1) if ($tmpfile1);
 190         unlink($tmpfile2) if ($tmpfile2);
 191 }
 192
 193
 194 sub usage
 195 {
 196         print ("Usage: mkknlimg [--dtok] [--270x] [--283x] <vmlinux|zImage|bzImage> <outfile>\n");
 197         exit(1);
 198 }
 199
 200 sub try_extract
 201 {
 202         my ($knl, $tmp) = @_;
 203
 204         my $ver = `strings "$knl" | grep -a -E "^Linux version [1-9]"`;
 205
 206         return undef if (!$ver);
 207
 208         chomp($ver);
 209
 210         my $res = { 'kver'=>$ver };
 211         $res->{'flags'} = strings_to_flags($knl, $wanted_strings);
 212
 213         return $res;
 214 }
 215
 216
 217 sub try_decompress
 218 {
 219         my ($magic, $subst, $zcat, $idx, $knl, $tmp1, $tmp2) = @_;
 220
 221         my $pos = `tr "$magic\n$subst" "\n$subst=" < "$knl" | grep -abo "^$subst"`;
 222         if ($pos)
 223         {
 224                 chomp($pos);
 225                 $pos = (split(/[\r\n]+/, $pos))[$idx];
 226                 return undef if (!defined($pos));
 227                 $pos =~ s/:.*[\r\n]*$//s;
 228                 my $cmd = "tail -c+$pos \"$knl\" | $zcat > $tmp2 2> /dev/null";
 229                 my $err = (system($cmd) >> 8);
 230                 return undef if (($err != 0) && ($err != 2));
 231
 232                 return try_extract($tmp2, $tmp1);
 233         }
 234
 235         return undef;
 236 }
 237
 238 sub strings_to_flags
 239 {
 240         my ($knl, $strings) = @_;
 241         my $string_pattern = '^('.join('|', keys(%$strings)).')$';
 242         my $flags = 0;
 243
 244         my @matches = `strings \"$knl\" | grep -E \"$string_pattern\"`;
 245         foreach my $match (@matches)
 246         {
 247             chomp($match);
 248             $flags |= $strings->{$match};
 249         }
 250
 251         return $flags;
 252 }
 253
 254 sub pack_trailer
 255 {
 256         my ($atoms) = @_;
 257         my $trailer = pack('VV', 0, 0);
 258         for (my $i = $#$atoms; $i>=0; $i--)
 259         {
 260                 my $atom = $atoms->[$i];
 261                 $trailer .= pack('a*x!4Va4', $atom->[1], length($atom->[1]), $atom->[0]);
 262         }
 263         return $trailer;
 264 }