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boot.c revision 1.21
      1  1.21    martin /*	$NetBSD: boot.c,v 1.21 2010/01/27 22:18:37 martin Exp $	*/
      2  1.12       cdi 
      3   1.1       mrg /*
      4   1.1       mrg  * Copyright (c) 1997, 1999 Eduardo E. Horvath.  All rights reserved.
      5   1.1       mrg  * Copyright (c) 1997 Jason R. Thorpe.  All rights reserved.
      6   1.1       mrg  * Copyright (C) 1995, 1996 Wolfgang Solfrank.
      7   1.1       mrg  * Copyright (C) 1995, 1996 TooLs GmbH.
      8   1.1       mrg  * All rights reserved.
      9   1.1       mrg  *
     10   1.1       mrg  * ELF support derived from NetBSD/alpha's boot loader, written
     11   1.1       mrg  * by Christopher G. Demetriou.
     12   1.1       mrg  *
     13   1.1       mrg  * Redistribution and use in source and binary forms, with or without
     14   1.1       mrg  * modification, are permitted provided that the following conditions
     15   1.1       mrg  * are met:
     16   1.1       mrg  * 1. Redistributions of source code must retain the above copyright
     17   1.1       mrg  *    notice, this list of conditions and the following disclaimer.
     18   1.1       mrg  * 2. Redistributions in binary form must reproduce the above copyright
     19   1.1       mrg  *    notice, this list of conditions and the following disclaimer in the
     20   1.1       mrg  *    documentation and/or other materials provided with the distribution.
     21   1.1       mrg  * 3. All advertising materials mentioning features or use of this software
     22   1.1       mrg  *    must display the following acknowledgement:
     23   1.1       mrg  *	This product includes software developed by TooLs GmbH.
     24   1.1       mrg  * 4. The name of TooLs GmbH may not be used to endorse or promote products
     25   1.1       mrg  *    derived from this software without specific prior written permission.
     26   1.1       mrg  *
     27   1.1       mrg  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
     28   1.1       mrg  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     29   1.1       mrg  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     30   1.1       mrg  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     31   1.1       mrg  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     32   1.1       mrg  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
     33   1.1       mrg  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
     34   1.1       mrg  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
     35   1.1       mrg  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
     36   1.1       mrg  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     37   1.1       mrg  */
     38   1.1       mrg 
     39   1.1       mrg /*
     40   1.1       mrg  * First try for the boot code
     41   1.1       mrg  *
     42   1.1       mrg  * Input syntax is:
     43   1.1       mrg  *	[promdev[{:|,}partition]]/[filename] [flags]
     44   1.1       mrg  */
     45   1.1       mrg 
     46   1.1       mrg #include <lib/libsa/stand.h>
     47  1.12       cdi #include <lib/libsa/loadfile.h>
     48   1.1       mrg #include <lib/libkern/libkern.h>
     49   1.1       mrg 
     50   1.1       mrg #include <sys/param.h>
     51   1.1       mrg #include <sys/reboot.h>
     52   1.1       mrg #include <sys/disklabel.h>
     53   1.2  jdolecek #include <sys/boot_flag.h>
     54   1.1       mrg 
     55   1.1       mrg #include <machine/cpu.h>
     56  1.12       cdi #include <machine/promlib.h>
     57  1.12       cdi #include <machine/bootinfo.h>
     58   1.1       mrg 
     59  1.12       cdi #include "boot.h"
     60   1.1       mrg #include "ofdev.h"
     61   1.1       mrg #include "openfirm.h"
     62   1.1       mrg 
     63  1.12       cdi 
     64  1.12       cdi #define COMPAT_BOOT(marks)	(marks[MARK_START] == marks[MARK_ENTRY])
     65  1.12       cdi 
     66  1.12       cdi 
     67  1.12       cdi typedef void (*entry_t)(long o0, long bootargs, long bootsize, long o3,
     68  1.12       cdi                         long ofw);
     69   1.1       mrg 
     70   1.1       mrg /*
     71   1.1       mrg  * Boot device is derived from ROM provided information, or if there is none,
     72   1.1       mrg  * this list is used in sequence, to find a kernel.
     73   1.1       mrg  */
     74  1.12       cdi const char *kernelnames[] = {
     75  1.12       cdi 	"netbsd",
     76  1.12       cdi 	"netbsd.gz",
     77  1.12       cdi 	"netbsd.old",
     78  1.12       cdi 	"netbsd.old.gz",
     79  1.12       cdi 	"onetbsd",
     80  1.12       cdi 	"onetbsd.gz",
     81   1.1       mrg 	"vmunix ",
     82   1.1       mrg #ifdef notyet
     83   1.1       mrg 	"netbsd.pl ",
     84   1.1       mrg 	"netbsd.pl.gz ",
     85   1.1       mrg 	"netbsd.el ",
     86   1.1       mrg 	"netbsd.el.gz ",
     87   1.1       mrg #endif
     88   1.1       mrg 	NULL
     89   1.1       mrg };
     90   1.1       mrg 
     91  1.12       cdi char bootdev[PROM_MAX_PATH];
     92   1.1       mrg 
     93  1.12       cdi int debug  = 0;
     94  1.12       cdi int compatmode = 0;
     95   1.1       mrg 
     96   1.1       mrg #if 0
     97   1.1       mrg static void
     98  1.13       uwe prom2boot(char *dev)
     99   1.1       mrg {
    100   1.1       mrg 	char *cp, *lp = 0;
    101   1.1       mrg 	int handle;
    102   1.1       mrg 	char devtype[16];
    103   1.1       mrg 
    104   1.1       mrg 	for (cp = dev; *cp; cp++)
    105   1.1       mrg 		if (*cp == ':')
    106   1.1       mrg 			lp = cp;
    107   1.1       mrg 	if (!lp)
    108   1.1       mrg 		lp = cp;
    109   1.1       mrg 	*lp = 0;
    110   1.1       mrg }
    111   1.1       mrg #endif
    112   1.1       mrg 
    113  1.12       cdi static int
    114  1.15    martin bootoptions(const char *ap, char *loaddev, char *kernel, char *options)
    115   1.1       mrg {
    116  1.12       cdi 	int v = 0;
    117  1.15    martin 	const char *start1 = NULL, *end1 = NULL, *start2 = NULL, *end2 = NULL;
    118  1.15    martin 	const char *path;
    119  1.17    martin 	char partition, *pp;
    120  1.12       cdi 
    121  1.12       cdi 	*kernel  = '\0';
    122  1.12       cdi 	*options = '\0';
    123  1.12       cdi 
    124  1.12       cdi 	if (ap == NULL) {
    125  1.12       cdi 		return (0);
    126  1.12       cdi 	}
    127  1.12       cdi 
    128  1.12       cdi 	while (*ap == ' ') {
    129  1.12       cdi 		ap++;
    130  1.12       cdi 	}
    131  1.12       cdi 
    132  1.12       cdi 	if (*ap != '-') {
    133  1.15    martin 		start1 = ap;
    134  1.12       cdi 		while (*ap != '\0' && *ap != ' ') {
    135  1.12       cdi 			ap++;
    136  1.12       cdi 		}
    137  1.15    martin 		end1 = ap;
    138   1.1       mrg 
    139  1.12       cdi 		while (*ap != '\0' && *ap == ' ') {
    140  1.12       cdi 			ap++;
    141  1.12       cdi 		}
    142  1.15    martin 
    143  1.15    martin 		if (*ap != '-') {
    144  1.15    martin 			start2 = ap;
    145  1.15    martin 			while (*ap != '\0' && *ap != ' ') {
    146  1.15    martin 				ap++;
    147  1.15    martin 			}
    148  1.15    martin 			end2 = ap;
    149  1.15    martin 			while (*ap != '\0' && *ap == ' ') {
    150  1.15    martin 				ap++;
    151  1.15    martin 			}
    152  1.15    martin 		}
    153  1.15    martin 	}
    154  1.15    martin 	if (end2 == start2) {
    155  1.15    martin 		start2 = end2 = NULL;
    156  1.15    martin 	}
    157  1.15    martin 	if (end1 == start1) {
    158  1.15    martin 		start1 = end1 = NULL;
    159  1.15    martin 	}
    160  1.15    martin 
    161  1.15    martin 	if (start1 == NULL) {
    162  1.15    martin 		/* only options */
    163  1.15    martin 	} else if (start2 == NULL) {
    164  1.15    martin 		memcpy(kernel, start1, (end1 - start1));
    165  1.15    martin 		kernel[end1 - start1] = '\0';
    166  1.15    martin 		path = filename(kernel, &partition);
    167  1.16    martin 		if (path == NULL) {
    168  1.16    martin 			strcpy(loaddev, kernel);
    169  1.16    martin 			kernel[0] = '\0';
    170  1.16    martin 		} else if (path != kernel) {
    171  1.15    martin 			/* copy device part */
    172  1.15    martin 			memcpy(loaddev, kernel, path-kernel);
    173  1.15    martin 			loaddev[path-kernel] = '\0';
    174  1.17    martin 			if (partition) {
    175  1.17    martin 				pp = loaddev + strlen(loaddev);
    176  1.17    martin 				pp[0] = ':';
    177  1.17    martin 				pp[1] = partition;
    178  1.17    martin 				pp[2] = '\0';
    179  1.17    martin 			}
    180  1.15    martin 			/* and kernel path */
    181  1.15    martin 			strcpy(kernel, path);
    182  1.15    martin 		}
    183  1.15    martin 	} else {
    184  1.15    martin 		memcpy(loaddev, start1, (end1-start1));
    185  1.15    martin 		loaddev[end1-start1] = '\0';
    186  1.15    martin 		memcpy(kernel, start2, (end2 - start2));
    187  1.15    martin 		kernel[end2 - start2] = '\0';
    188   1.1       mrg 	}
    189  1.12       cdi 
    190  1.12       cdi 	strcpy(options, ap);
    191  1.12       cdi 	while (*ap != '\0' && *ap != ' ' && *ap != '\t' && *ap != '\n') {
    192  1.12       cdi 		BOOT_FLAG(*ap, v);
    193  1.12       cdi 		switch(*ap++) {
    194   1.1       mrg 		case 'D':
    195   1.1       mrg 			debug = 2;
    196   1.1       mrg 			break;
    197  1.12       cdi 		case 'C':
    198  1.12       cdi 			compatmode = 1;
    199  1.12       cdi 			break;
    200   1.2  jdolecek 		default:
    201   1.1       mrg 			break;
    202   1.1       mrg 		}
    203   1.1       mrg 	}
    204  1.12       cdi 
    205  1.12       cdi 	if (((v & RB_KDB) != 0) && (debug == 0)) {
    206  1.12       cdi 		debug = 1;
    207  1.12       cdi 	}
    208  1.12       cdi 
    209  1.15    martin 	DPRINTF(("bootoptions: device='%s', kernel='%s', options='%s'\n",
    210  1.15    martin 	    loaddev, kernel, options));
    211  1.12       cdi 	return (v);
    212   1.1       mrg }
    213   1.1       mrg 
    214  1.12       cdi /*
    215  1.12       cdi  * The older (those relying on ofwboot v1.8 and earlier) kernels can't handle
    216  1.12       cdi  * ksyms information unless it resides in a dedicated memory allocated from
    217  1.12       cdi  * PROM and aligned on NBPG boundary. This is because the kernels calculate
    218  1.12       cdi  * their ends on their own, they use address of 'end[]' reference which follows
    219  1.12       cdi  * text segment. Ok, allocate some memory from PROM and copy symbol information
    220  1.12       cdi  * over there.
    221  1.12       cdi  */
    222  1.12       cdi static void
    223  1.12       cdi ksyms_copyout(void **ssym, void **esym)
    224  1.12       cdi {
    225  1.12       cdi 	void *addr;
    226  1.12       cdi 	int kssize = (int)(long)(*esym - *ssym + 1);
    227  1.12       cdi 
    228  1.12       cdi 	DPRINTF(("ksyms_copyout(): ssym = %p, esym = %p, kssize = %d\n",
    229  1.12       cdi 				*ssym, *esym, kssize));
    230   1.1       mrg 
    231  1.12       cdi 	if ( (addr = OF_claim(0, kssize, NBPG)) == (void *)-1) {
    232  1.12       cdi 		panic("ksyms_copyout(): no space for symbol table");
    233  1.12       cdi 	}
    234  1.12       cdi 
    235  1.12       cdi 	memcpy(addr, *ssym, kssize);
    236  1.12       cdi 	*ssym = addr;
    237  1.12       cdi 	*esym = addr + kssize - 1;
    238  1.12       cdi 
    239  1.12       cdi 	DPRINTF(("ksyms_copyout(): ssym = %p, esym = %p\n", *ssym, *esym));
    240  1.12       cdi }
    241  1.12       cdi 
    242  1.12       cdi /*
    243  1.12       cdi  * Prepare boot information and jump directly to the kernel.
    244  1.12       cdi  */
    245   1.1       mrg static void
    246  1.12       cdi jump_to_kernel(u_long *marks, char *kernel, char *args, void *ofw)
    247   1.1       mrg {
    248   1.1       mrg 	extern char end[];
    249   1.1       mrg 	int l, machine_tag;
    250  1.12       cdi 	long newargs[4];
    251  1.12       cdi 	void *ssym, *esym;
    252  1.12       cdi 	vaddr_t bootinfo;
    253  1.12       cdi 	struct btinfo_symtab bi_sym;
    254  1.12       cdi 	struct btinfo_kernend bi_kend;
    255  1.12       cdi 	char *cp;
    256  1.12       cdi 	char bootline[PROM_MAX_PATH * 2];
    257   1.1       mrg 
    258  1.12       cdi 	/* Compose kernel boot line. */
    259  1.12       cdi 	strncpy(bootline, kernel, sizeof(bootline));
    260  1.12       cdi 	cp = bootline + strlen(bootline);
    261  1.12       cdi 	if (*args) {
    262  1.12       cdi 		*cp++ = ' ';
    263  1.12       cdi 		strncpy(bootline, args, sizeof(bootline) - (cp - bootline));
    264  1.12       cdi 	}
    265  1.12       cdi 	*cp = 0; args = bootline;
    266  1.12       cdi 
    267  1.12       cdi 	/* Record symbol information in the bootinfo. */
    268  1.12       cdi 	bootinfo = bi_init(marks[MARK_END]);
    269  1.12       cdi 	bi_sym.nsym = marks[MARK_NSYM];
    270  1.12       cdi 	bi_sym.ssym = marks[MARK_SYM];
    271  1.12       cdi 	bi_sym.esym = marks[MARK_END];
    272  1.12       cdi 	bi_add(&bi_sym, BTINFO_SYMTAB, sizeof(bi_sym));
    273  1.12       cdi 	bi_kend.addr= bootinfo + BOOTINFO_SIZE;
    274  1.12       cdi 	bi_add(&bi_kend, BTINFO_KERNEND, sizeof(bi_kend));
    275  1.14    martin 	sparc64_finalize_tlb(marks[MARK_DATA]);
    276  1.12       cdi 	sparc64_bi_add();
    277  1.12       cdi 
    278  1.12       cdi 	ssym  = (void*)(long)marks[MARK_SYM];
    279  1.12       cdi 	esym  = (void*)(long)marks[MARK_END];
    280  1.12       cdi 
    281  1.12       cdi 	DPRINTF(("jump_to_kernel(): ssym = %p, esym = %p\n", ssym, esym));
    282  1.12       cdi 
    283  1.12       cdi 	/* Adjust ksyms pointers, if needed. */
    284  1.12       cdi 	if (COMPAT_BOOT(marks) || compatmode) {
    285  1.12       cdi 		ksyms_copyout(&ssym, &esym);
    286  1.12       cdi 	}
    287   1.1       mrg 
    288   1.1       mrg 	freeall();
    289   1.1       mrg 	/*
    290   1.1       mrg 	 * When we come in args consists of a pointer to the boot
    291   1.1       mrg 	 * string.  We need to fix it so it takes into account
    292   1.1       mrg 	 * other params such as romp.
    293   1.1       mrg 	 */
    294   1.1       mrg 
    295   1.1       mrg 	/*
    296   1.1       mrg 	 * Stash pointer to end of symbol table after the argument
    297   1.1       mrg 	 * strings.
    298   1.1       mrg 	 */
    299   1.1       mrg 	l = strlen(args) + 1;
    300  1.20    cegger 	memcpy(args + l, &esym, sizeof(esym));
    301   1.1       mrg 	l += sizeof(esym);
    302   1.1       mrg 
    303   1.1       mrg 	/*
    304   1.1       mrg 	 * Tell the kernel we're an OpenFirmware system.
    305   1.1       mrg 	 */
    306   1.1       mrg 	machine_tag = SPARC_MACHINE_OPENFIRMWARE;
    307  1.20    cegger 	memcpy(args + l, &machine_tag, sizeof(machine_tag));
    308   1.1       mrg 	l += sizeof(machine_tag);
    309   1.1       mrg 
    310   1.1       mrg 	/*
    311   1.1       mrg 	 * Since we don't need the boot string (we can get it from /chosen)
    312   1.1       mrg 	 * we won't pass it in.  Just pass in esym and magic #
    313   1.1       mrg 	 */
    314   1.1       mrg 	newargs[0] = SPARC_MACHINE_OPENFIRMWARE;
    315   1.1       mrg 	newargs[1] = (long)esym;
    316   1.1       mrg 	newargs[2] = (long)ssym;
    317  1.12       cdi 	newargs[3] = (long)(void*)bootinfo;
    318   1.1       mrg 	args = (char *)newargs;
    319   1.1       mrg 	l = sizeof(newargs);
    320   1.1       mrg 
    321   1.1       mrg 	/* if -D is set then pause in the PROM. */
    322  1.12       cdi 	if (debug > 1) callrom();
    323  1.12       cdi 
    324  1.12       cdi 	/*
    325  1.12       cdi 	 * Jump directly to the kernel. Solaris kernel and Sun PROM
    326  1.12       cdi 	 * flash updates expect ROMP vector in %o0, so we do. Format
    327  1.12       cdi 	 * of other parameters and their order reflect OF_chain()
    328  1.12       cdi 	 * symantics since this is what older NetBSD kernels rely on.
    329  1.12       cdi 	 * (see sparc64/include/bootinfo.h for specification).
    330  1.12       cdi 	 */
    331  1.12       cdi 	DPRINTF(("jump_to_kernel(%lx, %lx, %lx, %lx, %lx) @ %p\n", (long)ofw,
    332  1.12       cdi 				(long)args, (long)l, (long)ofw, (long)ofw,
    333  1.12       cdi 				(void*)marks[MARK_ENTRY]));
    334  1.12       cdi 	(*(entry_t)marks[MARK_ENTRY])((long)ofw, (long)args, (long)l, (long)ofw,
    335  1.12       cdi 				      (long)ofw);
    336  1.12       cdi 	printf("Returned from kernel entry point!\n");
    337   1.1       mrg }
    338   1.1       mrg 
    339  1.12       cdi static void
    340  1.12       cdi start_kernel(char *kernel, char *bootline, void *ofw)
    341   1.1       mrg {
    342   1.1       mrg 	int fd;
    343  1.12       cdi 	u_long marks[MARK_MAX];
    344   1.1       mrg 
    345   1.1       mrg 	/*
    346  1.12       cdi 	 * First, load headers using default allocator and check whether kernel
    347  1.12       cdi 	 * entry address matches kernel text load address. If yes, this is the
    348  1.12       cdi 	 * old kernel designed for ofwboot v1.8 and therefore it must be mapped
    349  1.12       cdi 	 * by PROM. Otherwise, map the kernel with 4MB permanent pages.
    350   1.1       mrg 	 */
    351  1.12       cdi 	loadfile_set_allocator(LOADFILE_NOP_ALLOCATOR);
    352  1.12       cdi 	if ( (fd = loadfile(kernel, marks, LOAD_HDR|COUNT_TEXT)) != -1) {
    353  1.12       cdi 		if (COMPAT_BOOT(marks) || compatmode) {
    354  1.12       cdi 			(void)printf("[c] ");
    355  1.12       cdi 			loadfile_set_allocator(LOADFILE_OFW_ALLOCATOR);
    356  1.12       cdi 		} else {
    357  1.12       cdi 			loadfile_set_allocator(LOADFILE_MMU_ALLOCATOR);
    358  1.12       cdi 		}
    359  1.12       cdi 		(void)printf("Loading %s: ", kernel);
    360   1.1       mrg 
    361  1.12       cdi 		if (fdloadfile(fd, marks, LOAD_ALL) != -1) {
    362  1.21    martin 			close(fd);
    363  1.12       cdi 			jump_to_kernel(marks, kernel, bootline, ofw);
    364   1.1       mrg 		}
    365   1.1       mrg 	}
    366  1.12       cdi 	(void)printf("Failed to load '%s'.\n", kernel);
    367   1.1       mrg }
    368   1.1       mrg 
    369  1.15    martin static void
    370  1.15    martin help(void)
    371  1.15    martin {
    372  1.15    martin 	printf( "enter a special command\n"
    373  1.15    martin 		"  halt\n"
    374  1.15    martin 		"  exit\n"
    375  1.15    martin 		"    to return to OpenFirmware\n"
    376  1.15    martin 		"  ?\n"
    377  1.15    martin 		"  help\n"
    378  1.15    martin 		"    to display this message\n"
    379  1.15    martin 		"or a boot specification:\n"
    380  1.15    martin 		"  [device] [kernel] [options]\n"
    381  1.15    martin 		"\n"
    382  1.15    martin 		"for example:\n"
    383  1.15    martin 		"  disk:a netbsd -s\n");
    384  1.15    martin }
    385  1.15    martin 
    386  1.12       cdi void
    387  1.12       cdi main(void *ofw)
    388  1.12       cdi {
    389  1.12       cdi 	int boothowto, i = 0;
    390   1.1       mrg 
    391  1.12       cdi 	char kernel[PROM_MAX_PATH];
    392  1.12       cdi 	char bootline[PROM_MAX_PATH];
    393   1.1       mrg 
    394  1.12       cdi 	/* Initialize OpenFirmware */
    395  1.12       cdi 	romp = ofw;
    396  1.12       cdi 	prom_init();
    397   1.1       mrg 
    398   1.7    martin 	printf("\r>> %s, Revision %s\n", bootprog_name, bootprog_rev);
    399  1.15    martin 	DPRINTF((">> (%s, %s)\n", bootprog_maker, bootprog_date));
    400   1.1       mrg 
    401  1.12       cdi 	/* Figure boot arguments */
    402  1.12       cdi 	strncpy(bootdev, prom_getbootpath(), sizeof(bootdev) - 1);
    403  1.15    martin 	boothowto = bootoptions(prom_getbootargs(), bootdev, kernel, bootline);
    404  1.12       cdi 
    405  1.12       cdi 	for (;; *kernel = '\0') {
    406   1.1       mrg 		if (boothowto & RB_ASKNAME) {
    407  1.12       cdi 			char *cp, cmdline[PROM_MAX_PATH];
    408  1.12       cdi 
    409   1.1       mrg 			printf("Boot: ");
    410  1.12       cdi 			gets(cmdline);
    411  1.12       cdi 
    412  1.15    martin 			if (!strcmp(cmdline,"exit") ||
    413  1.15    martin 			    !strcmp(cmdline,"halt")) {
    414  1.12       cdi 				prom_halt();
    415  1.15    martin 			} else if (!strcmp(cmdline, "?") ||
    416  1.15    martin 				   !strcmp(cmdline, "help")) {
    417  1.15    martin 				help();
    418  1.15    martin 				continue;
    419  1.12       cdi 			}
    420  1.15    martin 
    421  1.15    martin 			boothowto  = bootoptions(cmdline, bootdev, kernel,
    422  1.15    martin 			    bootline);
    423  1.15    martin 			boothowto |= RB_ASKNAME;
    424  1.15    martin 			i = 0;
    425   1.1       mrg 		}
    426  1.12       cdi 
    427  1.12       cdi 		if (*kernel == '\0') {
    428  1.12       cdi 			if (kernelnames[i] == NULL) {
    429  1.12       cdi 				boothowto |= RB_ASKNAME;
    430  1.12       cdi 				continue;
    431  1.12       cdi 			}
    432  1.12       cdi 			strncpy(kernel, kernelnames[i++], PROM_MAX_PATH);
    433  1.12       cdi 		} else if (i == 0) {
    434  1.12       cdi 			/*
    435  1.12       cdi 			 * Kernel name was passed via command line -- ask user
    436  1.12       cdi 			 * again if requested image fails to boot.
    437  1.12       cdi 			 */
    438  1.12       cdi 			boothowto |= RB_ASKNAME;
    439  1.12       cdi 		}
    440  1.12       cdi 
    441  1.12       cdi 		start_kernel(kernel, bootline, ofw);
    442  1.12       cdi 
    443   1.1       mrg 		/*
    444  1.12       cdi 		 * Try next name from kernel name list if not in askname mode,
    445  1.12       cdi 		 * enter askname on reaching list's end.
    446   1.1       mrg 		 */
    447  1.12       cdi 		if ((boothowto & RB_ASKNAME) == 0 && (kernelnames[i] != NULL)) {
    448  1.12       cdi 			printf(": trying %s...\n", kernelnames[i]);
    449   1.1       mrg 		} else {
    450   1.1       mrg 			printf("\n");
    451   1.1       mrg 			boothowto |= RB_ASKNAME;
    452   1.1       mrg 		}
    453   1.1       mrg 	}
    454   1.1       mrg 
    455  1.12       cdi 	(void)printf("Boot failed! Exiting to the Firmware.\n");
    456  1.12       cdi 	prom_halt();
    457   1.1       mrg }
    458