xref: /titanic_41/usr/src/uts/sun4/os/forthdebug.c (revision b86efd96f8acd85ddaa930a2f0c1d664237e4aaf)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/types.h>
30 #include <sys/cmn_err.h>
31 #include <sys/modctl.h>
32 #include <sys/kobj.h>
33 #include <sys/kobj_impl.h>
34 #include <sys/promif.h>
35 #include <sys/promimpl.h>
36 #include <sys/reboot.h>
37 #include <sys/bootconf.h>
38 #include <sys/systm.h>		/* strstr */
39 #include <sys/machsystm.h>	/* obpdebug */
40 
41 #define	FDEBUGFILE	"misc/forthdebug"
42 #define	INSTALL_DBP	"kdbg-words dbp-install previous"
43 #define	SYMBOL_END	"END OF SYMBOL"
44 
45 #ifdef DEBUG
46 static int forthdebug	= 1;
47 #else
48 static int forthdebug	= 0;
49 #endif /* DEBUG */
50 
51 static int forthdebug_dbp = 0;
52 int forthdebug_supported = 1;
53 int modreloc_flag = KOBJ_RELOCATED;
54 
55 /*
56  * basic_sym[] holds all essential symbols the symbol lookup
57  * service requires. Forthdebug stub names appears in forthdebug
58  * as place holders. They are replaced with the value of corresponding
59  * kernel variables. For example, "modules-val-here" in forthdebug
60  * is replaced with the address of "modules" variable.
61  *
62  * To improve performance, we mandate the records be in the same
63  * sequence they appear in forthdebug, i.e "modules-val-here" is
64  * ahead of "primaries-v-here" in misc/forthdebug.
65  *
66  * The last record must be all 0 to indicate end of the array.
67  */
68 static char *basic_sym[] = {
69 	/* kernel variable */	/* forthdebug stub name - must be 16 chars */
70 	"modules",		"modules-val-here",
71 	"primaries",		"primaries-v-here",
72 	"modreloc_flag",	"modreloc-flagval",
73 	0,			0
74 };
75 
76 static void fdbp_hook() {} /* null function for defer breakpoint operation */
77 
78 /*ARGSUSED*/
79 static void fdbp_snoop(unsigned int i, struct modctl *modctl_p)
80 {
81 	promif_preprom();
82 	fdbp_hook();
83 	promif_postprom();
84 }
85 
86 static kobj_notify_list_t knl_load = {
87 	fdbp_snoop, KOBJ_NOTIFY_MODLOADED, 0, 0
88 };
89 
90 static kobj_notify_list_t knl_unload = {
91 	fdbp_snoop, KOBJ_NOTIFY_MODUNLOADING, 0, 0
92 };
93 
94 void
95 forthdebug_init(void)
96 {
97 	char *fth_buf, *buf_p;
98 	ulong_t modsym;
99 	int i, sz;
100 	struct bootstat bstat;
101 	struct _buf *file;
102 
103 	if (!forthdebug_supported) {
104 		(void) modload("misc", "obpsym");
105 		return;
106 	}
107 
108 	forthdebug_dbp |= boothowto & RB_FORTHDEBUGDBP;
109 	forthdebug |= (boothowto & RB_FORTHDEBUG) | forthdebug_dbp;
110 
111 	file = kobj_open_path(FDEBUGFILE, 1, 1);
112 	if (file == (struct _buf *)-1) {
113 		cmn_err(CE_CONT, "Can't open %s\n", FDEBUGFILE);
114 		return;
115 	}
116 
117 	i = BOP_FSTAT(bootops, file->_fd, &bstat);
118 	if (i || !bstat.st_size) {
119 		cmn_err(CE_CONT, "Can't stat %s stat=%x sz=%llx\n",
120 			FDEBUGFILE, i, (long long)bstat.st_size);
121 		goto err_stat;
122 	}
123 
124 	fth_buf = (char *)kobj_zalloc(bstat.st_size + 1, KM_SLEEP);
125 	sz = kobj_read_file(file, fth_buf, bstat.st_size, 0); /* entire file */
126 	if (sz < 0) {
127 		cmn_err(CE_CONT, "Error(%d) reading %s\n", sz, FDEBUGFILE);
128 		goto done;
129 	}
130 	ASSERT(bstat.st_size == sz);
131 	fth_buf[sz] = 0;
132 
133 	/* resolve all essential symbols in basic_sym[] */
134 	for (i = 0; basic_sym[i]; i += 2) {
135 		buf_p = strstr(fth_buf, basic_sym[i + 1]);
136 		modsym = kobj_getsymvalue(basic_sym[i], 0);
137 		if (buf_p && modsym) {
138 			(void) sprintf(buf_p, "%16p", (void *)modsym);
139 			buf_p += 16;
140 			*buf_p++ = ' ';	/* erase null char by sprintf */
141 		} else {
142 			cmn_err(CE_CONT,
143 			    "forthdebug_init: No %s symbol(%p,%p), aborted\n",
144 			    basic_sym[i], (void *)buf_p, (void *)modsym);
145 			goto done;
146 		}
147 	}
148 	if (!forthdebug) {	/* symbol lookup services only */
149 		if (!(buf_p = strstr(fth_buf, SYMBOL_END))) {
150 			cmn_err(CE_CONT, "No %s in forthdebug\n", SYMBOL_END);
151 			goto done;
152 		}
153 		*buf_p = '\0';
154 #ifdef DEBUG
155 		cmn_err(CE_CONT, "symbol lookup service (%ld bytes)\n",
156 			(long)(buf_p - fth_buf));
157 #endif /* DEBUG */
158 		prom_interpret(fth_buf, 0, 0, 0, 0, 0);
159 		goto done;
160 	}
161 
162 	cmn_err(CE_CONT, "%s (%d bytes) ", FDEBUGFILE, sz);
163 	prom_interpret(fth_buf, 0, 0, 0, 0, 0);
164 	cmn_err(CE_CONT, "loaded\n");
165 	obpdebug = 1;	/* backward compatibility */
166 
167 	if (forthdebug_dbp) {
168 #ifdef NO_KOBJ_NOTIFY
169 		modsym = kobj_getsymvalue("kobj_notify_add", 0);
170 		(void) ((int (*)(kobj_notify_list_t *))modsym)(&knl_load);
171 		(void) ((int (*)(kobj_notify_list_t *))modsym)(&knl_unload);
172 #else
173 		(void) kobj_notify_add(&knl_load);
174 		(void) kobj_notify_add(&knl_unload);
175 #endif	/* NO_KOBJ_NOTIFY */
176 		prom_interpret(INSTALL_DBP, 0, 0, 0, 0, 0);
177 		debug_enter("Defer breakpoint enabled. Add breakpoints, then");
178 	}
179 done:
180 	kobj_free(fth_buf, bstat.st_size + 1);
181 err_stat:
182 	kobj_close_file(file);
183 
184 	if (boothowto & RB_HALT)
185 		debug_enter("forthdebug: halt flag (-h) is set.\n");
186 }
187