File: /usr/src/linux/arch/ppc/boot/utils/mkprep.c
1 /*
2 * BK Id: SCCS/s.mkprep.c 1.7 05/18/01 06:20:29 patch
3 */
4 /*
5 * Makes a prep bootable image which can be dd'd onto
6 * a disk device to make a bootdisk. Will take
7 * as input a elf executable, strip off the header
8 * and write out a boot image as:
9 * 1) default - strips elf header
10 * suitable as a network boot image
11 * 2) -pbp - strips elf header and writes out prep boot partition image
12 * cat or dd onto disk for booting
13 * 3) -asm - strips elf header and writes out as asm data
14 * useful for generating data for a compressed image
15 * -- Cort
16 *
17 * Modified for x86 hosted builds by Matt Porter <porter@neta.com>
18 */
19
20 #include <fcntl.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24 #include <sys/stat.h>
25 #include <unistd.h>
26
27 #define cpu_to_le32(x) le32_to_cpu((x))
28 unsigned long le32_to_cpu(unsigned long x)
29 {
30 return (((x & 0x000000ffU) << 24) |
31 ((x & 0x0000ff00U) << 8) |
32 ((x & 0x00ff0000U) >> 8) |
33 ((x & 0xff000000U) >> 24));
34 }
35
36
37 #define cpu_to_le16(x) le16_to_cpu((x))
38 unsigned short le16_to_cpu(unsigned short x)
39 {
40 return (((x & 0x00ff) << 8) |
41 ((x & 0xff00) >> 8));
42 }
43
44 #define cpu_to_be32(x) (x)
45 #define be32_to_cpu(x) (x)
46 #define cpu_to_be16(x) (x)
47 #define be16_to_cpu(x) (x)
48
49 /* size of read buffer */
50 #define SIZE 0x1000
51
52
53 typedef unsigned long dword_t;
54 typedef unsigned short word_t;
55 typedef unsigned char byte_t;
56 typedef byte_t block_t[512];
57 typedef byte_t page_t[4096];
58
59
60 /*
61 * Partition table entry
62 * - from the PReP spec
63 */
64 typedef struct partition_entry {
65 byte_t boot_indicator;
66 byte_t starting_head;
67 byte_t starting_sector;
68 byte_t starting_cylinder;
69
70 byte_t system_indicator;
71 byte_t ending_head;
72 byte_t ending_sector;
73 byte_t ending_cylinder;
74
75 dword_t beginning_sector;
76 dword_t number_of_sectors;
77 } partition_entry_t;
78
79 #define BootActive 0x80
80 #define SystemPrep 0x41
81
82 void copy_image(int , int);
83 void write_prep_partition(int , int );
84 void write_asm_data( int in, int out );
85
86 unsigned int elfhdr_size = 65536;
87
88 int main(int argc, char *argv[])
89 {
90 int in_fd, out_fd;
91 int argptr = 1;
92 unsigned int prep = 0;
93 unsigned int asmoutput = 0;
94
95 if ( (argc < 3) || (argc > 4) )
96 {
97 fprintf(stderr, "usage: %s [-pbp] [-asm] <boot-file> <image>\n",argv[0]);
98 exit(-1);
99 }
100
101 /* needs to handle args more elegantly -- but this is a small/simple program */
102
103 /* check for -pbp */
104 if ( !strcmp( argv[argptr], "-pbp" ) )
105 {
106 prep = 1;
107 argptr++;
108 }
109
110 /* check for -asm */
111 if ( !strcmp( argv[argptr], "-asm" ) )
112 {
113 asmoutput = 1;
114 argptr++;
115 }
116
117 /* input file */
118 if ( !strcmp( argv[argptr], "-" ) )
119 in_fd = 0; /* stdin */
120 else
121 if ((in_fd = open( argv[argptr] , 0)) < 0)
122 exit(-1);
123 argptr++;
124
125 /* output file */
126 if ( !strcmp( argv[argptr], "-" ) )
127 out_fd = 1; /* stdout */
128 else
129 if ((out_fd = creat( argv[argptr] , 0755)) < 0)
130 exit(-1);
131 argptr++;
132
133 /* skip elf header in input file */
134 /*if ( !prep )*/
135 lseek(in_fd, elfhdr_size, SEEK_SET);
136
137 /* write prep partition if necessary */
138 if ( prep )
139 write_prep_partition( in_fd, out_fd );
140
141 /* write input image to bootimage */
142 if ( asmoutput )
143 write_asm_data( in_fd, out_fd );
144 else
145 copy_image(in_fd, out_fd);
146
147 return 0;
148 }
149
150 void write_prep_partition(int in, int out)
151 {
152 unsigned char block[512];
153 partition_entry_t *pe = (partition_entry_t *)&block[0x1BE];
154 dword_t *entry = (dword_t *)&block[0];
155 dword_t *length = (dword_t *)&block[sizeof(long)];
156 struct stat info;
157
158 if (fstat(in, &info) < 0)
159 {
160 fprintf(stderr,"info failed\n");
161 exit(-1);
162 }
163
164 bzero( block, sizeof block );
165
166 /* set entry point and boot image size skipping over elf header */
167 #ifdef __i386__
168 *entry = 0x400/*+65536*/;
169 *length = info.st_size-elfhdr_size+0x400;
170 #else
171 *entry = cpu_to_le32(0x400/*+65536*/);
172 *length = cpu_to_le32(info.st_size-elfhdr_size+0x400);
173 #endif /* __i386__ */
174
175 /* sets magic number for msdos partition (used by linux) */
176 block[510] = 0x55;
177 block[511] = 0xAA;
178
179 /*
180 * Build a "PReP" partition table entry in the boot record
181 * - "PReP" may only look at the system_indicator
182 */
183 pe->boot_indicator = BootActive;
184 pe->system_indicator = SystemPrep;
185 /*
186 * The first block of the diskette is used by this "boot record" which
187 * actually contains the partition table. (The first block of the
188 * partition contains the boot image, but I digress...) We'll set up
189 * one partition on the diskette and it shall contain the rest of the
190 * diskette.
191 */
192 pe->starting_head = 0; /* zero-based */
193 pe->starting_sector = 2; /* one-based */
194 pe->starting_cylinder = 0; /* zero-based */
195 pe->ending_head = 1; /* assumes two heads */
196 pe->ending_sector = 18; /* assumes 18 sectors/track */
197 pe->ending_cylinder = 79; /* assumes 80 cylinders/diskette */
198
199 /*
200 * The "PReP" software ignores the above fields and just looks at
201 * the next two.
202 * - size of the diskette is (assumed to be)
203 * (2 tracks/cylinder)(18 sectors/tracks)(80 cylinders/diskette)
204 * - unlike the above sector numbers, the beginning sector is zero-based!
205 */
206 #if 0
207 pe->beginning_sector = cpu_to_le32(1);
208 #else
209 /* This has to be 0 on the PowerStack? */
210 #ifdef __i386__
211 pe->beginning_sector = 0;
212 #else
213 pe->beginning_sector = cpu_to_le32(0);
214 #endif /* __i386__ */
215 #endif
216
217 #ifdef __i386__
218 pe->number_of_sectors = 2*18*80-1;
219 #else
220 pe->number_of_sectors = cpu_to_le32(2*18*80-1);
221 #endif /* __i386__ */
222
223 write( out, block, sizeof(block) );
224 write( out, entry, sizeof(*entry) );
225 write( out, length, sizeof(*length) );
226 /* set file position to 2nd sector where image will be written */
227 lseek( out, 0x400, SEEK_SET );
228 }
229
230
231
232 void
233 copy_image(int in, int out)
234 {
235 char buf[SIZE];
236 int n;
237
238 while ( (n = read(in, buf, SIZE)) > 0 )
239 write(out, buf, n);
240 }
241
242
243 void
244 write_asm_data( int in, int out )
245 {
246 int i, cnt, pos, len;
247 unsigned int cksum, val;
248 unsigned char *lp;
249 unsigned char buf[SIZE];
250 unsigned char str[256];
251
252 write( out, "\t.data\n\t.globl input_data\ninput_data:\n",
253 strlen( "\t.data\n\t.globl input_data\ninput_data:\n" ) );
254 pos = 0;
255 cksum = 0;
256 while ((len = read(in, buf, sizeof(buf))) > 0)
257 {
258 cnt = 0;
259 lp = (unsigned char *)buf;
260 len = (len + 3) & ~3; /* Round up to longwords */
261 for (i = 0; i < len; i += 4)
262 {
263 if (cnt == 0)
264 {
265 write( out, "\t.long\t", strlen( "\t.long\t" ) );
266 }
267 sprintf( str, "0x%02X%02X%02X%02X", lp[0], lp[1], lp[2], lp[3]);
268 write( out, str, strlen(str) );
269 val = *(unsigned long *)lp;
270 cksum ^= val;
271 lp += 4;
272 if (++cnt == 4)
273 {
274 cnt = 0;
275 sprintf( str, " # %x \n", pos+i-12);
276 write( out, str, strlen(str) );
277 } else
278 {
279 write( out, ",", 1 );
280 }
281 }
282 if (cnt)
283 {
284 write( out, "0\n", 2 );
285 }
286 pos += len;
287 }
288 sprintf(str, "\t.globl input_len\ninput_len:\t.long\t0x%x\n", pos);
289 write( out, str, strlen(str) );
290
291 fprintf(stderr, "cksum = %x\n", cksum);
292 }
293