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/arch/x86/boot/tools/build.c

https://bitbucket.org/ndreys/linux-sunxi
C | 247 lines | 185 code | 27 blank | 35 comment | 32 complexity | 5efc8b605981fd7ceb08c144fd7daf38 MD5 | raw file
Possible License(s): GPL-2.0, LGPL-2.0, AGPL-1.0
  1/*
  2 *  Copyright (C) 1991, 1992  Linus Torvalds
  3 *  Copyright (C) 1997 Martin Mares
  4 *  Copyright (C) 2007 H. Peter Anvin
  5 */
  6
  7/*
  8 * This file builds a disk-image from two different files:
  9 *
 10 * - setup: 8086 machine code, sets up system parm
 11 * - system: 80386 code for actual system
 12 *
 13 * It does some checking that all files are of the correct type, and
 14 * just writes the result to stdout, removing headers and padding to
 15 * the right amount. It also writes some system data to stderr.
 16 */
 17
 18/*
 19 * Changes by tytso to allow root device specification
 20 * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
 21 * Cross compiling fixes by Gertjan van Wingerde, July 1996
 22 * Rewritten by Martin Mares, April 1997
 23 * Substantially overhauled by H. Peter Anvin, April 2007
 24 */
 25
 26#include <stdio.h>
 27#include <string.h>
 28#include <stdlib.h>
 29#include <stdarg.h>
 30#include <sys/types.h>
 31#include <sys/stat.h>
 32#include <sys/sysmacros.h>
 33#include <unistd.h>
 34#include <fcntl.h>
 35#include <sys/mman.h>
 36#include <asm/boot.h>
 37
 38typedef unsigned char  u8;
 39typedef unsigned short u16;
 40typedef unsigned long  u32;
 41
 42#define DEFAULT_MAJOR_ROOT 0
 43#define DEFAULT_MINOR_ROOT 0
 44
 45/* Minimal number of setup sectors */
 46#define SETUP_SECT_MIN 5
 47#define SETUP_SECT_MAX 64
 48
 49/* This must be large enough to hold the entire setup */
 50u8 buf[SETUP_SECT_MAX*512];
 51int is_big_kernel;
 52
 53/*----------------------------------------------------------------------*/
 54
 55static const u32 crctab32[] = {
 56	0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419,
 57	0x706af48f, 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4,
 58	0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07,
 59	0x90bf1d91, 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de,
 60	0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 0x136c9856,
 61	0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
 62	0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4,
 63	0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
 64	0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3,
 65	0x45df5c75, 0xdcd60dcf, 0xabd13d59, 0x26d930ac, 0x51de003a,
 66	0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599,
 67	0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
 68	0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190,
 69	0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f,
 70	0x9fbfe4a5, 0xe8b8d433, 0x7807c9a2, 0x0f00f934, 0x9609a88e,
 71	0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
 72	0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed,
 73	0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
 74	0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3,
 75	0xfbd44c65, 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2,
 76	0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a,
 77	0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5,
 78	0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, 0xbe0b1010,
 79	0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
 80	0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17,
 81	0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6,
 82	0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615,
 83	0x73dc1683, 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8,
 84	0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 0xf00f9344,
 85	0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
 86	0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a,
 87	0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
 88	0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1,
 89	0xa6bc5767, 0x3fb506dd, 0x48b2364b, 0xd80d2bda, 0xaf0a1b4c,
 90	0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef,
 91	0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
 92	0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe,
 93	0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31,
 94	0x2cd99e8b, 0x5bdeae1d, 0x9b64c2b0, 0xec63f226, 0x756aa39c,
 95	0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
 96	0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b,
 97	0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
 98	0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1,
 99	0x18b74777, 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,
100	0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, 0xa00ae278,
101	0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7,
102	0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 0x40df0b66,
103	0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
104	0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605,
105	0xcdd70693, 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8,
106	0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b,
107	0x2d02ef8d
108};
109
110static u32 partial_crc32_one(u8 c, u32 crc)
111{
112	return crctab32[(crc ^ c) & 0xff] ^ (crc >> 8);
113}
114
115static u32 partial_crc32(const u8 *s, int len, u32 crc)
116{
117	while (len--)
118		crc = partial_crc32_one(*s++, crc);
119	return crc;
120}
121
122static void die(const char * str, ...)
123{
124	va_list args;
125	va_start(args, str);
126	vfprintf(stderr, str, args);
127	fputc('\n', stderr);
128	exit(1);
129}
130
131static void usage(void)
132{
133	die("Usage: build setup system [rootdev] [> image]");
134}
135
136int main(int argc, char ** argv)
137{
138	unsigned int i, sz, setup_sectors;
139	int c;
140	u32 sys_size;
141	u8 major_root, minor_root;
142	struct stat sb;
143	FILE *file;
144	int fd;
145	void *kernel;
146	u32 crc = 0xffffffffUL;
147
148	if ((argc < 3) || (argc > 4))
149		usage();
150	if (argc > 3) {
151		if (!strcmp(argv[3], "CURRENT")) {
152			if (stat("/", &sb)) {
153				perror("/");
154				die("Couldn't stat /");
155			}
156			major_root = major(sb.st_dev);
157			minor_root = minor(sb.st_dev);
158		} else if (strcmp(argv[3], "FLOPPY")) {
159			if (stat(argv[3], &sb)) {
160				perror(argv[3]);
161				die("Couldn't stat root device.");
162			}
163			major_root = major(sb.st_rdev);
164			minor_root = minor(sb.st_rdev);
165		} else {
166			major_root = 0;
167			minor_root = 0;
168		}
169	} else {
170		major_root = DEFAULT_MAJOR_ROOT;
171		minor_root = DEFAULT_MINOR_ROOT;
172	}
173	fprintf(stderr, "Root device is (%d, %d)\n", major_root, minor_root);
174
175	/* Copy the setup code */
176	file = fopen(argv[1], "r");
177	if (!file)
178		die("Unable to open `%s': %m", argv[1]);
179	c = fread(buf, 1, sizeof(buf), file);
180	if (ferror(file))
181		die("read-error on `setup'");
182	if (c < 1024)
183		die("The setup must be at least 1024 bytes");
184	if (buf[510] != 0x55 || buf[511] != 0xaa)
185		die("Boot block hasn't got boot flag (0xAA55)");
186	fclose(file);
187
188	/* Pad unused space with zeros */
189	setup_sectors = (c + 511) / 512;
190	if (setup_sectors < SETUP_SECT_MIN)
191		setup_sectors = SETUP_SECT_MIN;
192	i = setup_sectors*512;
193	memset(buf+c, 0, i-c);
194
195	/* Set the default root device */
196	buf[508] = minor_root;
197	buf[509] = major_root;
198
199	fprintf(stderr, "Setup is %d bytes (padded to %d bytes).\n", c, i);
200
201	/* Open and stat the kernel file */
202	fd = open(argv[2], O_RDONLY);
203	if (fd < 0)
204		die("Unable to open `%s': %m", argv[2]);
205	if (fstat(fd, &sb))
206		die("Unable to stat `%s': %m", argv[2]);
207	sz = sb.st_size;
208	fprintf (stderr, "System is %d kB\n", (sz+1023)/1024);
209	kernel = mmap(NULL, sz, PROT_READ, MAP_SHARED, fd, 0);
210	if (kernel == MAP_FAILED)
211		die("Unable to mmap '%s': %m", argv[2]);
212	/* Number of 16-byte paragraphs, including space for a 4-byte CRC */
213	sys_size = (sz + 15 + 4) / 16;
214
215	/* Patch the setup code with the appropriate size parameters */
216	buf[0x1f1] = setup_sectors-1;
217	buf[0x1f4] = sys_size;
218	buf[0x1f5] = sys_size >> 8;
219	buf[0x1f6] = sys_size >> 16;
220	buf[0x1f7] = sys_size >> 24;
221
222	crc = partial_crc32(buf, i, crc);
223	if (fwrite(buf, 1, i, stdout) != i)
224		die("Writing setup failed");
225
226	/* Copy the kernel code */
227	crc = partial_crc32(kernel, sz, crc);
228	if (fwrite(kernel, 1, sz, stdout) != sz)
229		die("Writing kernel failed");
230
231	/* Add padding leaving 4 bytes for the checksum */
232	while (sz++ < (sys_size*16) - 4) {
233		crc = partial_crc32_one('\0', crc);
234		if (fwrite("\0", 1, 1, stdout) != 1)
235			die("Writing padding failed");
236	}
237
238	/* Write the CRC */
239	fprintf(stderr, "CRC %lx\n", crc);
240	if (fwrite(&crc, 1, 4, stdout) != 4)
241		die("Writing CRC failed");
242
243	close(fd);
244
245	/* Everything is OK */
246	return 0;
247}