File: mkbugboot.c

package info (click to toggle)
kernel-source-2.4.27 2.4.27-10sarge5
  • links: PTS
  • area: main
  • in suites: sarge
  • size: 191,224 kB
  • ctags: 610,077
  • sloc: ansic: 3,299,602; asm: 164,708; makefile: 10,962; sh: 3,725; perl: 2,273; yacc: 1,651; cpp: 820; lex: 752; tcl: 577; awk: 251; lisp: 218; sed: 79
file content (184 lines) | stat: -rw-r--r-- 4,641 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
/*
 * arch/ppc/pp3boot/mkbugboot.c
 *
 * Makes a Motorola PPCBUG ROM bootable image which can be flashed
 * into one of the FLASH banks on a Motorola PowerPlus board.
 *
 * Author: Matt Porter <mporter@mvista.com>
 *
 * Copyright 2001 MontaVista Software Inc.
 *
 * This program is free software; you can redistribute  it and/or modify it
 * under  the terms of  the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 */

#define ELF_HEADER_SIZE	65536

#include <unistd.h>
#include <sys/stat.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <fcntl.h>

#ifdef __i386__
#define cpu_to_be32(x) le32_to_cpu(x)
#define cpu_to_be16(x) le16_to_cpu(x)
#else
#define cpu_to_be32(x) (x)
#define cpu_to_be16(x) (x)
#endif

#define cpu_to_le32(x) le32_to_cpu((x))
unsigned long le32_to_cpu(unsigned long x)
{
     	return (((x & 0x000000ffU) << 24) |
		((x & 0x0000ff00U) <<  8) |
		((x & 0x00ff0000U) >>  8) |
		((x & 0xff000000U) >> 24));
}

#define cpu_to_le16(x) le16_to_cpu((x))
unsigned short le16_to_cpu(unsigned short x)
{
	return (((x & 0x00ff) << 8) |
		((x & 0xff00) >> 8));
}

/* size of read buffer */
#define SIZE 0x1000

/* PPCBUG ROM boot header */
typedef struct bug_boot_header {
  unsigned char	magic_word[4];		/* "BOOT" */
  unsigned long	entry_offset;		/* Offset from top of header to code */
  unsigned long	routine_length;		/* Length of code */
  unsigned char	routine_name[8];	/* Name of the boot code */
} bug_boot_header_t;

#define HEADER_SIZE	sizeof(bug_boot_header_t)

unsigned long copy_image(int32_t in_fd, int32_t out_fd)
{
  unsigned char buf[SIZE];
  int n;
  unsigned long image_size = 0;
  unsigned char zero = 0;

  lseek(in_fd, ELF_HEADER_SIZE, SEEK_SET);

  /* Copy an image while recording its size */
  while ( (n = read(in_fd, buf, SIZE)) > 0 )
    {
    image_size = image_size + n;
    write(out_fd, buf, n);
    }

  /* BUG romboot requires that our size is divisible by 2 */
  /* align image to 2 byte boundary */
  if (image_size % 2)
    {
    image_size++;
    write(out_fd, &zero, 1);
    }

  return image_size;
}

void write_bugboot_header(int32_t out_fd, unsigned long boot_size)
{
  unsigned char header_block[HEADER_SIZE];
  bug_boot_header_t *bbh = (bug_boot_header_t *)&header_block[0];

  memset(header_block, 0, HEADER_SIZE);

  /* Fill in the PPCBUG ROM boot header */
  strncpy(bbh->magic_word, "BOOT", 4);		/* PPCBUG magic word */
  bbh->entry_offset = cpu_to_be32(HEADER_SIZE);	/* Entry address */
  bbh->routine_length= cpu_to_be32(HEADER_SIZE+boot_size+2);	/* Routine length */
  strncpy(bbh->routine_name, "LINUXROM", 8);		/* Routine name   */

  /* Output the header and bootloader to the file */
  write(out_fd, header_block, HEADER_SIZE);
}

unsigned short calc_checksum(int32_t bug_fd)
{
  unsigned long checksum_var = 0;
  unsigned char buf[2];
  int n;

  /* Checksum loop */
  while ( (n = read(bug_fd, buf, 2) ) )
  {
    checksum_var = checksum_var + *(unsigned short *)buf;

    /* If we carry out, mask it and add one to the checksum */
    if (checksum_var >> 16)
      checksum_var = (checksum_var & 0x0000ffff) + 1;
  }

  return checksum_var;
}

int main(int argc, char *argv[])
{
  int32_t image_fd, bugboot_fd;
  int argptr = 1;
  unsigned long kernel_size = 0;
  unsigned short checksum = 0;
  unsigned char bugbootname[256];

  if ( (argc != 3) )
  {
    fprintf(stderr, "usage: %s <kernel_image> <bugboot>\n",argv[0]);
    exit(-1);
  }

  /* Get file args */

  /* kernel image file */
    if ((image_fd = open( argv[argptr] , 0)) < 0)
      exit(-1);
  argptr++;

  /* bugboot file */
  if ( !strcmp( argv[argptr], "-" ) )
    bugboot_fd = 1;			/* stdout */
  else
    if ((bugboot_fd = creat( argv[argptr] , 0755)) < 0)
      exit(-1);
    else
      strcpy(bugbootname, argv[argptr]);
  argptr++;

  /* Set file position after ROM header block where zImage will be written */
  lseek(bugboot_fd, HEADER_SIZE, SEEK_SET);

  /* Copy kernel image into bugboot image */
  kernel_size = copy_image(image_fd, bugboot_fd);
  close(image_fd);

  /* Set file position to beginning where header/romboot will be written */
  lseek(bugboot_fd, 0, SEEK_SET);

  /* Write out BUG header/romboot */
  write_bugboot_header(bugboot_fd, kernel_size);

  /* Close bugboot file */
  close(bugboot_fd);

  /* Reopen it as read/write */
  bugboot_fd = open(bugbootname, O_RDWR);

  /* Calculate checksum */
  checksum = calc_checksum(bugboot_fd);

  /* Write out the calculated checksum */
  write(bugboot_fd, &checksum, 2);

  return 0;
}