arch/ppc/boot/utils/mkprep.c

   1 /*
   2  * Makes a prep bootable image which can be dd'd onto
   3  * a disk device to make a bootdisk.  Will take
   4  * as input a elf executable, strip off the header
   5  * and write out a boot image as:
   6  * 1) default - strips elf header
   7  *      suitable as a network boot image
   8  * 2) -pbp - strips elf header and writes out prep boot partition image
   9  *      cat or dd onto disk for booting
  10  * 3) -asm - strips elf header and writes out as asm data
  11  *      useful for generating data for a compressed image
  12  *                  -- Cort
  13  *
  14  * Modified for x86 hosted builds by Matt Porter <porter@neta.com>
  15  * Modified for Sparc hosted builds by Peter Wahl <PeterWahl@web.de>
  16  */
  17
  18 #include <fcntl.h>
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <strings.h>
  23 #include <sys/stat.h>
  24 #include <unistd.h>
  25
  26 #define cpu_to_le32(x) le32_to_cpu((x))
  27 unsigned long le32_to_cpu(unsigned long x)
  28 {
  29         return (((x & 0x000000ffU) << 24) |
  30                 ((x & 0x0000ff00U) <<  8) |
  31                 ((x & 0x00ff0000U) >>  8) |
  32                 ((x & 0xff000000U) >> 24));
  33 }
  34
  35
  36 #define cpu_to_le16(x) le16_to_cpu((x))
  37 unsigned short le16_to_cpu(unsigned short x)
  38 {
  39         return (((x & 0x00ff) << 8) |
  40                 ((x & 0xff00) >> 8));
  41 }
  42
  43 #define cpu_to_be32(x) (x)
  44 #define be32_to_cpu(x) (x)
  45 #define cpu_to_be16(x) (x)
  46 #define be16_to_cpu(x) (x)
  47
  48 /* size of read buffer */
  49 #define SIZE 0x1000
  50
  51
  52 typedef unsigned long dword_t;
  53 typedef unsigned short word_t;
  54 typedef unsigned char byte_t;
  55 typedef byte_t block_t[512];
  56 typedef byte_t page_t[4096];
  57
  58
  59 /*
  60  * Partition table entry
  61  *  - from the PReP spec
  62  */
  63 typedef struct partition_entry {
  64   byte_t        boot_indicator;
  65   byte_t        starting_head;
  66   byte_t        starting_sector;
  67   byte_t        starting_cylinder;
  68
  69   byte_t        system_indicator;
  70   byte_t        ending_head;
  71   byte_t        ending_sector;
  72   byte_t        ending_cylinder;
  73
  74   dword_t       beginning_sector;
  75   dword_t       number_of_sectors;
  76 } partition_entry_t;
  77
  78 #define BootActive      0x80
  79 #define SystemPrep      0x41
  80
  81 void copy_image(int , int);
  82 void write_prep_partition(int , int );
  83 void write_asm_data( int in, int out );
  84
  85 unsigned int elfhdr_size = 65536;
  86
  87 int main(int argc, char *argv[])
  88 {
  89   int in_fd, out_fd;
  90   int argptr = 1;
  91   unsigned int prep = 0;
  92   unsigned int asmoutput = 0;
  93
  94   if ( (argc < 3) || (argc > 4) )
  95   {
  96     fprintf(stderr, "usage: %s [-pbp] [-asm] <boot-file> <image>\n",argv[0]);
  97     exit(-1);
  98   }
  99
 100   /* needs to handle args more elegantly -- but this is a small/simple program */
 101
 102   /* check for -pbp */
 103   if ( !strcmp( argv[argptr], "-pbp" ) )
 104   {
 105     prep = 1;
 106     argptr++;
 107   }
 108
 109   /* check for -asm */
 110   if ( !strcmp( argv[argptr], "-asm" ) )
 111   {
 112     asmoutput = 1;
 113     argptr++;
 114   }
 115
 116   /* input file */
 117   if ( !strcmp( argv[argptr], "-" ) )
 118     in_fd = 0;                  /* stdin */
 119   else
 120     if ((in_fd = open( argv[argptr] , 0)) < 0)
 121       exit(-1);
 122   argptr++;
 123
 124   /* output file */
 125   if ( !strcmp( argv[argptr], "-" ) )
 126     out_fd = 1;                 /* stdout */
 127   else
 128     if ((out_fd = creat( argv[argptr] , 0755)) < 0)
 129       exit(-1);
 130   argptr++;
 131
 132   /* skip elf header in input file */
 133   /*if ( !prep )*/
 134   lseek(in_fd, elfhdr_size, SEEK_SET);
 135
 136   /* write prep partition if necessary */
 137   if ( prep )
 138           write_prep_partition( in_fd, out_fd );
 139
 140   /* write input image to bootimage */
 141   if ( asmoutput )
 142           write_asm_data( in_fd, out_fd );
 143   else
 144           copy_image(in_fd, out_fd);
 145
 146   return 0;
 147 }
 148
 149 void write_prep_partition(int in, int out)
 150 {
 151   unsigned char block[512];
 152   partition_entry_t pe;
 153   dword_t *entry  = (dword_t *)&block[0];
 154   dword_t *length = (dword_t *)&block[sizeof(long)];
 155   struct stat info;
 156
 157   if (fstat(in, &info) < 0)
 158   {
 159     fprintf(stderr,"info failed\n");
 160     exit(-1);
 161   }
 162
 163   bzero( block, sizeof block );
 164
 165   /* set entry point and boot image size skipping over elf header */
 166 #ifdef __i386__
 167   *entry = 0x400/*+65536*/;
 168   *length = info.st_size-elfhdr_size+0x400;
 169 #else
 170   *entry = cpu_to_le32(0x400/*+65536*/);
 171   *length = cpu_to_le32(info.st_size-elfhdr_size+0x400);
 172 #endif /* __i386__ */
 173
 174   /* sets magic number for msdos partition (used by linux) */
 175   block[510] = 0x55;
 176   block[511] = 0xAA;
 177
 178   /*
 179    * Build a "PReP" partition table entry in the boot record
 180    *  - "PReP" may only look at the system_indicator
 181    */
 182   pe.boot_indicator   = BootActive;
 183   pe.system_indicator = SystemPrep;
 184   /*
 185    * The first block of the diskette is used by this "boot record" which
 186    * actually contains the partition table. (The first block of the
 187    * partition contains the boot image, but I digress...)  We'll set up
 188    * one partition on the diskette and it shall contain the rest of the
 189    * diskette.
 190    */
 191   pe.starting_head     = 0;     /* zero-based                        */
 192   pe.starting_sector   = 2;     /* one-based                         */
 193   pe.starting_cylinder = 0;     /* zero-based                        */
 194   pe.ending_head       = 1;     /* assumes two heads                 */
 195   pe.ending_sector     = 18;    /* assumes 18 sectors/track          */
 196   pe.ending_cylinder   = 79;    /* assumes 80 cylinders/diskette     */
 197
 198   /*
 199    * The "PReP" software ignores the above fields and just looks at
 200    * the next two.
 201    *   - size of the diskette is (assumed to be)
 202    *     (2 tracks/cylinder)(18 sectors/tracks)(80 cylinders/diskette)
 203    *   - unlike the above sector numbers, the beginning sector is zero-based!
 204    */
 205 #if 0
 206   pe.beginning_sector  = cpu_to_le32(1);
 207 #else
 208   /* This has to be 0 on the PowerStack? */
 209 #ifdef __i386__
 210   pe.beginning_sector  = 0;
 211 #else
 212   pe.beginning_sector  = cpu_to_le32(0);
 213 #endif /* __i386__ */
 214 #endif
 215
 216 #ifdef __i386__
 217   pe.number_of_sectors = 2*18*80-1;
 218 #else
 219   pe.number_of_sectors = cpu_to_le32(2*18*80-1);
 220 #endif /* __i386__ */
 221
 222   memcpy(&block[0x1BE], &pe, sizeof(pe));
 223
 224   write( out, block, sizeof(block) );
 225   write( out, entry, sizeof(*entry) );
 226   write( out, length, sizeof(*length) );
 227   /* set file position to 2nd sector where image will be written */
 228   lseek( out, 0x400, SEEK_SET );
 229 }
 230
 231
 232
 233 void
 234 copy_image(int in, int out)
 235 {
 236   char buf[SIZE];
 237   int n;
 238
 239   while ( (n = read(in, buf, SIZE)) > 0 )
 240     write(out, buf, n);
 241 }
 242
 243
 244 void
 245 write_asm_data( int in, int out )
 246 {
 247   int i, cnt, pos, len;
 248   unsigned int cksum, val;
 249   unsigned char *lp;
 250   unsigned char buf[SIZE];
 251   unsigned char str[256];
 252
 253   write( out, "\t.data\n\t.globl input_data\ninput_data:\n",
 254          strlen( "\t.data\n\t.globl input_data\ninput_data:\n" ) );
 255   pos = 0;
 256   cksum = 0;
 257   while ((len = read(in, buf, sizeof(buf))) > 0)
 258   {
 259     cnt = 0;
 260     lp = (unsigned char *)buf;
 261     len = (len + 3) & ~3;  /* Round up to longwords */
 262     for (i = 0;  i < len;  i += 4)
 263     {
 264       if (cnt == 0)
 265       {
 266         write( out, "\t.long\t", strlen( "\t.long\t" ) );
 267       }
 268       sprintf( str, "0x%02X%02X%02X%02X", lp[0], lp[1], lp[2], lp[3]);
 269       write( out, str, strlen(str) );
 270       val = *(unsigned long *)lp;
 271       cksum ^= val;
 272       lp += 4;
 273       if (++cnt == 4)
 274       {
 275         cnt = 0;
 276         sprintf( str, " # %x \n", pos+i-12);
 277         write( out, str, strlen(str) );
 278       } else
 279       {
 280         write( out, ",", 1 );
 281       }
 282     }
 283     if (cnt)
 284     {
 285       write( out, "0\n", 2 );
 286     }
 287     pos += len;
 288   }
 289   sprintf(str, "\t.globl input_len\ninput_len:\t.long\t0x%x\n", pos);
 290   write( out, str, strlen(str) );
 291
 292   fprintf(stderr, "cksum = %x\n", cksum);
 293 }