xref: /freebsd/stand/i386/isoboot/isoboot.c (revision 8aac90f18aef7c9eea906c3ff9a001ca7b94f375)
1 /*-
2  * Copyright (c) 1998 Robert Nordier
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms are freely
6  * permitted provided that the above copyright notice and this
7  * paragraph and the following disclaimer are duplicated in all
8  * such forms.
9  *
10  * This software is provided "AS IS" and without any express or
11  * implied warranties, including, without limitation, the implied
12  * warranties of merchantability and fitness for a particular
13  * purpose.
14  */
15 
16 #include <sys/param.h>
17 #include <sys/gpt.h>
18 #include <sys/dirent.h>
19 #include <sys/reboot.h>
20 
21 #include <machine/bootinfo.h>
22 #include <machine/elf.h>
23 #include <machine/pc/bios.h>
24 #include <machine/psl.h>
25 
26 #include <stdarg.h>
27 
28 #include <a.out.h>
29 
30 #include <btxv86.h>
31 
32 #include "stand.h"
33 
34 #include "bootargs.h"
35 #include "lib.h"
36 #include "rbx.h"
37 #include "drv.h"
38 #include "cons.h"
39 #include "gpt.h"
40 #include "paths.h"
41 
42 #define ARGS		0x900
43 #define NOPT		14
44 #define NDEV		3
45 #define MEM_BASE	0x12
46 #define MEM_EXT 	0x15
47 
48 #define DRV_HARD	0x80
49 #define DRV_MASK	0x7f
50 
51 #define TYPE_AD		0
52 #define TYPE_DA		1
53 #define TYPE_MAXHARD	TYPE_DA
54 #define TYPE_FD		2
55 
56 extern uint32_t _end;
57 
58 static const char optstr[NOPT] = "DhaCcdgmnpqrsv"; /* Also 'P', 'S' */
59 static const unsigned char flags[NOPT] = {
60 	RBX_DUAL,
61 	RBX_SERIAL,
62 	RBX_ASKNAME,
63 	RBX_CDROM,
64 	RBX_CONFIG,
65 	RBX_KDB,
66 	RBX_GDB,
67 	RBX_MUTE,
68 	RBX_NOINTR,
69 	RBX_PAUSE,
70 	RBX_QUIET,
71 	RBX_DFLTROOT,
72 	RBX_SINGLE,
73 	RBX_VERBOSE
74 };
75 uint32_t opts;
76 
77 static const char *const dev_nm[NDEV] = {"ad", "da", "fd"};
78 static const unsigned char dev_maj[NDEV] = {30, 4, 2};
79 
80 static struct dsk dsk;
81 static char kname[1024];
82 static int comspeed = SIOSPD;
83 static struct bootinfo bootinfo;
84 
85 static vm_offset_t	high_heap_base;
86 static uint32_t		bios_basemem, bios_extmem, high_heap_size;
87 
88 static struct bios_smap smap;
89 
90 /*
91  * The minimum amount of memory to reserve in bios_extmem for the heap.
92  */
93 #define	HEAP_MIN	(3 * 1024 * 1024)
94 
95 static char *heap_next;
96 static char *heap_end;
97 
98 int main(void);
99 
100 static void load(void);
101 static int parse_cmds(char *, int *);
102 
103 static uint8_t ls, dsk_meta;
104 static uint32_t fs_off;
105 
106 #include "cd9660read.c"
107 
108 static inline int
109 xfsread(uint64_t inode, void *buf, size_t nbyte)
110 {
111 
112 	if ((size_t)cd9660_fsread(inode, buf, nbyte) != nbyte) {
113 		printf("Invalid %s\n", "format");
114 		return (-1);
115 	}
116 	return (0);
117 }
118 
119 static void
120 bios_getmem(void)
121 {
122 	uint64_t size;
123 
124 	/* Parse system memory map */
125 	v86.ebx = 0;
126 	do {
127 		v86.ctl = V86_FLAGS;
128 		v86.addr = MEM_EXT;		/* int 0x15 function 0xe820*/
129 		v86.eax = 0xe820;
130 		v86.ecx = sizeof(struct bios_smap);
131 		v86.edx = SMAP_SIG;
132 		v86.es = VTOPSEG(&smap);
133 		v86.edi = VTOPOFF(&smap);
134 		v86int();
135 		if ((v86.efl & 1) || (v86.eax != SMAP_SIG))
136 			break;
137 		/* look for a low-memory segment that's large enough */
138 		if ((smap.type == SMAP_TYPE_MEMORY) && (smap.base == 0) &&
139 		    (smap.length >= (512 * 1024)))
140 			bios_basemem = smap.length;
141 		/* look for the first segment in 'extended' memory */
142 		if ((smap.type == SMAP_TYPE_MEMORY) &&
143 		    (smap.base == 0x100000)) {
144 			bios_extmem = smap.length;
145 		}
146 
147 		/*
148 		 * Look for the largest segment in 'extended' memory beyond
149 		 * 1MB but below 4GB.
150 		 */
151 		if ((smap.type == SMAP_TYPE_MEMORY) &&
152 		    (smap.base > 0x100000) && (smap.base < 0x100000000ull)) {
153 			size = smap.length;
154 
155 			/*
156 			 * If this segment crosses the 4GB boundary,
157 			 * truncate it.
158 			 */
159 			if (smap.base + size > 0x100000000ull)
160 				size = 0x100000000ull - smap.base;
161 
162 			if (size > high_heap_size) {
163 				high_heap_size = size;
164 				high_heap_base = smap.base;
165 			}
166 		}
167 	} while (v86.ebx != 0);
168 
169 	/* Fall back to the old compatibility function for base memory */
170 	if (bios_basemem == 0) {
171 		v86.ctl = 0;
172 		v86.addr = 0x12;		/* int 0x12 */
173 		v86int();
174 
175 		bios_basemem = (v86.eax & 0xffff) * 1024;
176 	}
177 
178 	/*
179 	 * Fall back through several compatibility functions for extended
180 	 * memory
181 	 */
182 	if (bios_extmem == 0) {
183 		v86.ctl = V86_FLAGS;
184 		v86.addr = 0x15;		/* int 0x15 function 0xe801*/
185 		v86.eax = 0xe801;
186 		v86int();
187 		if (!(v86.efl & 1)) {
188 			bios_extmem = ((v86.ecx & 0xffff) +
189 			    ((v86.edx & 0xffff) * 64)) * 1024;
190 		}
191 	}
192 	if (bios_extmem == 0) {
193 		v86.ctl = 0;
194 		v86.addr = 0x15;		/* int 0x15 function 0x88*/
195 		v86.eax = 0x8800;
196 		v86int();
197 		bios_extmem = (v86.eax & 0xffff) * 1024;
198 	}
199 
200 	/*
201 	 * If we have extended memory and did not find a suitable heap
202 	 * region in the SMAP, use the last 3MB of 'extended' memory as a
203 	 * high heap candidate.
204 	 */
205 	if (bios_extmem >= HEAP_MIN && high_heap_size < HEAP_MIN) {
206 		high_heap_size = HEAP_MIN;
207 		high_heap_base = bios_extmem + 0x100000 - HEAP_MIN;
208 	}
209 }
210 
211 int
212 main(void)
213 {
214 	char cmd[512], cmdtmp[512];
215 	ssize_t sz;
216 	int autoboot, dskupdated;
217 	uint64_t ino;
218 
219 	bios_getmem();
220 
221 	if (high_heap_size > 0) {
222 		heap_end = PTOV(high_heap_base + high_heap_size);
223 		heap_next = PTOV(high_heap_base);
224 	} else {
225 		heap_next = (char *)
226 		    (roundup2(__base + (int32_t)&_end, 0x10000) - __base);
227 		heap_end = (char *)PTOV(bios_basemem);
228 	}
229 	setheap(heap_next, heap_end);
230 
231 	v86.ctl = V86_FLAGS;
232 	v86.efl = PSL_RESERVED_DEFAULT | PSL_I;
233 	dsk.drive = *(uint8_t *)PTOV(ARGS);
234 	dsk.type = dsk.drive & DRV_HARD ? TYPE_AD : TYPE_FD;
235 	dsk.unit = dsk.drive & DRV_MASK;
236 	dsk.part = -1;
237 	dsk.start = 0;
238 	bootinfo.bi_version = BOOTINFO_VERSION;
239 	bootinfo.bi_size = sizeof(bootinfo);
240 	bootinfo.bi_basemem = bios_basemem / 1024;
241 	bootinfo.bi_extmem = bios_extmem / 1024;
242 	bootinfo.bi_memsizes_valid++;
243 	bootinfo.bi_bios_dev = dsk.drive;
244 
245 	autoboot = 1;
246 	*cmd = '\0';
247 
248 	for (;;) {
249 		*kname = '\0';
250 		if ((ino = cd9660_lookup(PATH_CONFIG)) ||
251 		    (ino = cd9660_lookup(PATH_DOTCONFIG))) {
252 			sz = cd9660_fsread(ino, cmd, sizeof(cmd) - 1);
253 			cmd[(sz < 0) ? 0 : sz] = '\0';
254 		}
255 		if (*cmd != '\0') {
256 			memcpy(cmdtmp, cmd, sizeof(cmdtmp));
257 			if (parse_cmds(cmdtmp, &dskupdated))
258 				break;
259 			if (!OPT_CHECK(RBX_QUIET))
260 				printf("%s: %s", PATH_CONFIG, cmd);
261 			*cmd = '\0';
262 		}
263 
264 		if (autoboot && keyhit(3)) {
265 			if (*kname == '\0')
266 				memcpy(kname, PATH_LOADER, sizeof(PATH_LOADER));
267 			break;
268 		}
269 		autoboot = 0;
270 
271 		/*
272 		 * Try to exec stage 3 boot loader. If interrupted by a
273 		 * keypress, or in case of failure, try to load a kernel
274 		 * directly instead.
275 		 */
276 		if (*kname != '\0')
277 			load();
278 		memcpy(kname, PATH_LOADER, sizeof(PATH_LOADER));
279 		load();
280 		memcpy(kname, PATH_KERNEL, sizeof(PATH_KERNEL));
281 		load();
282 		dsk_meta = 0;
283 	}
284 
285 	/* Present the user with the boot2 prompt. */
286 
287 	for (;;) {
288 		if (!OPT_CHECK(RBX_QUIET)) {
289 			printf("\nFreeBSD/x86 boot\n"
290 			    "Default: %u:%s(%up%u)%s\n"
291 			    "boot: ",
292 			    dsk.drive & DRV_MASK, dev_nm[dsk.type], dsk.unit,
293 			    dsk.part, kname);
294 		}
295 		if (ioctrl & IO_SERIAL)
296 			sio_flush();
297 		*cmd = '\0';
298 		if (keyhit(0))
299 			getstr(cmd, sizeof(cmd));
300 		else if (!OPT_CHECK(RBX_QUIET))
301 			putchar('\n');
302 		if (parse_cmds(cmd, &dskupdated)) {
303 			putchar('\a');
304 			continue;
305 		}
306 		load();
307 	}
308 	/* NOTREACHED */
309 }
310 
311 /* Needed so btxld can link us properly; do not remove. */
312 void
313 exit(int x)
314 {
315 
316 	while (1);
317 	__unreachable();
318 }
319 
320 static void
321 load(void)
322 {
323 	union {
324 		struct exec ex;
325 		Elf32_Ehdr eh;
326 	} hdr;
327 	static Elf32_Phdr ep[2];
328 	static Elf32_Shdr es[2];
329 	caddr_t p;
330 	uint64_t ino;
331 	uint32_t addr, x;
332 	int fmt, i, j;
333 
334 	if (!(ino = cd9660_lookup(kname))) {
335 		if (!ls) {
336 			printf("%s: No %s on %u:%s(%up%u)\n", BOOTPROG,
337 			    kname, dsk.drive & DRV_MASK, dev_nm[dsk.type],
338 			    dsk.unit,
339 			    dsk.part);
340 		}
341 		return;
342 	}
343 	if (xfsread(ino, &hdr, sizeof(hdr)))
344 		return;
345 	if (N_GETMAGIC(hdr.ex) == ZMAGIC)
346 		fmt = 0;
347 	else if (IS_ELF(hdr.eh))
348 		fmt = 1;
349 	else {
350 		printf("Invalid %s\n", "format");
351 		return;
352 	}
353 	if (fmt == 0) {
354 		addr = hdr.ex.a_entry & 0xffffff;
355 		p = PTOV(addr);
356 		fs_off = PAGE_SIZE;
357 		if (xfsread(ino, p, hdr.ex.a_text))
358 			return;
359 		p += roundup2(hdr.ex.a_text, PAGE_SIZE);
360 		if (xfsread(ino, p, hdr.ex.a_data))
361 			return;
362 		p += hdr.ex.a_data + roundup2(hdr.ex.a_bss, PAGE_SIZE);
363 		bootinfo.bi_symtab = VTOP(p);
364 		memcpy(p, &hdr.ex.a_syms, sizeof(hdr.ex.a_syms));
365 		p += sizeof(hdr.ex.a_syms);
366 		if (hdr.ex.a_syms) {
367 			if (xfsread(ino, p, hdr.ex.a_syms))
368 				return;
369 			p += hdr.ex.a_syms;
370 			if (xfsread(ino, p, sizeof(int)))
371 				return;
372 			x = *(uint32_t *)p;
373 			p += sizeof(int);
374 			x -= sizeof(int);
375 			if (xfsread(ino, p, x))
376 				return;
377 			p += x;
378 		}
379 	} else {
380 		fs_off = hdr.eh.e_phoff;
381 		for (j = i = 0; i < hdr.eh.e_phnum && j < 2; i++) {
382 			if (xfsread(ino, ep + j, sizeof(ep[0])))
383 				return;
384 			if (ep[j].p_type == PT_LOAD)
385 				j++;
386 		}
387 		for (i = 0; i < 2; i++) {
388 			p = PTOV(ep[i].p_paddr & 0xffffff);
389 			fs_off = ep[i].p_offset;
390 			if (xfsread(ino, p, ep[i].p_filesz))
391 				return;
392 		}
393 		p += roundup2(ep[1].p_memsz, PAGE_SIZE);
394 		bootinfo.bi_symtab = VTOP(p);
395 		if (hdr.eh.e_shnum == hdr.eh.e_shstrndx + 3) {
396 			fs_off = hdr.eh.e_shoff + sizeof(es[0]) *
397 			    (hdr.eh.e_shstrndx + 1);
398 			if (xfsread(ino, &es, sizeof(es)))
399 				return;
400 			for (i = 0; i < 2; i++) {
401 				memcpy(p, &es[i].sh_size,
402 				    sizeof(es[i].sh_size));
403 				p += sizeof(es[i].sh_size);
404 				fs_off = es[i].sh_offset;
405 				if (xfsread(ino, p, es[i].sh_size))
406 					return;
407 				p += es[i].sh_size;
408 			}
409 		}
410 		addr = hdr.eh.e_entry & 0xffffff;
411 	}
412 	bootinfo.bi_esymtab = VTOP(p);
413 	bootinfo.bi_kernelname = VTOP(kname);
414 	bootinfo.bi_bios_dev = dsk.drive;
415 	__exec((caddr_t)addr, RB_BOOTINFO | (opts & RBX_MASK),
416 	    MAKEBOOTDEV(dev_maj[dsk.type], 0, dsk.unit, 0),
417 	    0, 0, 0, VTOP(&bootinfo));
418 }
419 
420 static int
421 parse_cmds(char *cmdstr, int *dskupdated)
422 {
423 	char *arg;
424 	char *ep, *p, *q;
425 	const char *cp;
426 	unsigned int drv;
427 	int c, i, j;
428 
429 	arg = cmdstr;
430 	*dskupdated = 0;
431 	while ((c = *arg++)) {
432 		if (c == ' ' || c == '\t' || c == '\n')
433 			continue;
434 		for (p = arg; *p && *p != '\n' && *p != ' ' && *p != '\t'; p++);
435 		ep = p;
436 		if (*p)
437 			*p++ = 0;
438 		if (c == '-') {
439 			while ((c = *arg++)) {
440 				if (c == 'P') {
441 					if (*(uint8_t *)PTOV(0x496) & 0x10) {
442 						cp = "yes";
443 					} else {
444 						opts |= OPT_SET(RBX_DUAL) |
445 						    OPT_SET(RBX_SERIAL);
446 						cp = "no";
447 					}
448 					printf("Keyboard: %s\n", cp);
449 					continue;
450 				} else if (c == 'S') {
451 					j = 0;
452 					while ((unsigned int)(i = *arg++ - '0')
453 					    <= 9)
454 						j = j * 10 + i;
455 					if (j > 0 && i == -'0') {
456 						comspeed = j;
457 						break;
458 					}
459 					/*
460 					 * Fall through to error below
461 					 * ('S' not in optstr[]).
462 					 */
463 				}
464 				for (i = 0; c != optstr[i]; i++)
465 					if (i == NOPT - 1)
466 						return (-1);
467 				opts ^= OPT_SET(flags[i]);
468 			}
469 			ioctrl = OPT_CHECK(RBX_DUAL) ? (IO_SERIAL|IO_KEYBOARD) :
470 			    OPT_CHECK(RBX_SERIAL) ? IO_SERIAL : IO_KEYBOARD;
471 			if (ioctrl & IO_SERIAL) {
472 				if (sio_init(115200 / comspeed) != 0)
473 					ioctrl &= ~IO_SERIAL;
474 			}
475 		} else {
476 			for (q = arg--; *q && *q != '('; q++);
477 			if (*q) {
478 				drv = -1;
479 				if (arg[1] == ':') {
480 					drv = *arg - '0';
481 					if (drv > 9)
482 						return (-1);
483 					arg += 2;
484 				}
485 				if (q - arg != 2)
486 					return (-1);
487 				for (i = 0; arg[0] != dev_nm[i][0] ||
488 				    arg[1] != dev_nm[i][1]; i++)
489 					if (i == NDEV - 1)
490 						return (-1);
491 				dsk.type = i;
492 				arg += 3;
493 				dsk.unit = *arg - '0';
494 				if (arg[1] != 'p' || dsk.unit > 9)
495 					return (-1);
496 				arg += 2;
497 				dsk.part = *arg - '0';
498 				if (dsk.part < 1 || dsk.part > 9)
499 					return (-1);
500 				arg++;
501 				if (arg[0] != ')')
502 					return (-1);
503 				arg++;
504 				if (drv == -1)
505 					drv = dsk.unit;
506 				dsk.drive = (dsk.type <= TYPE_MAXHARD
507 				    ? DRV_HARD : 0) + drv;
508 				*dskupdated = 1;
509 			}
510 			if ((i = ep - arg)) {
511 				if ((size_t)i >= sizeof(kname))
512 					return (-1);
513 				memcpy(kname, arg, i + 1);
514 			}
515 		}
516 		arg = p;
517 	}
518 	return (0);
519 }
520