xref: /netbsd-src/sys/arch/arm/arm32/kgdb_machdep.c (revision da5f4674a3fc214be3572d358b66af40ab9401e7)
1 /*	$NetBSD: kgdb_machdep.c,v 1.2 2003/07/15 00:24:42 lukem Exp $	*/
2 
3 /*
4  * Copyright (c) 1996 Matthias Pfaller.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by Matthias Pfaller.
18  * 4. The name of the author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: kgdb_machdep.c,v 1.2 2003/07/15 00:24:42 lukem Exp $");
35 
36 #include "opt_ddb.h"
37 #include "opt_kgdb.h"
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/kgdb.h>
42 
43 #include <uvm/uvm_extern.h>
44 
45 #include <machine/frame.h>
46 #include <machine/reg.h>
47 #include <machine/trap.h>
48 
49 /*
50  * Determine if the memory at va..(va+len) is valid.
51  */
52 int
53 kgdb_acc(va, len)
54 	vaddr_t va;
55 	size_t len;
56 {
57 	vaddr_t last_va;
58 
59 	last_va = va + len;
60 	va  &= ~PGOFSET;
61 	last_va &= ~PGOFSET;
62 
63 	do {
64 		if (db_validate_address(va))
65 			return (0);
66 		va  += PAGE_SIZE;
67 	} while (va < last_va);
68 
69 	return (1);
70 }
71 
72 /*
73  * Translate a trap number into a unix compatible signal value.
74  * (gdb only understands unix signal numbers).
75  */
76 int
77 kgdb_signal(type)
78 	int type;
79 {
80 
81 	switch (type) {
82 	case T_BREAKPOINT:
83 		return(SIGTRAP);
84 	case -1:
85 		return(SIGSEGV);
86 	default:
87 		return(SIGINT);
88 	}
89 }
90 
91 /*
92  * Definitions exported from gdb.
93  */
94 
95 /*
96  * Translate the values stored in the kernel regs struct to the format
97  * understood by gdb.
98  */
99 void
100 kgdb_getregs(regs, gdb_regs)
101 	db_regs_t *regs;
102 	kgdb_reg_t *gdb_regs;
103 {
104 
105 	gdb_regs[KGDB_REGNUM_R0 +  0] = regs->tf_r0;
106 	gdb_regs[KGDB_REGNUM_R0 +  1] = regs->tf_r1;
107 	gdb_regs[KGDB_REGNUM_R0 +  2] = regs->tf_r2;
108 	gdb_regs[KGDB_REGNUM_R0 +  3] = regs->tf_r3;
109 	gdb_regs[KGDB_REGNUM_R0 +  4] = regs->tf_r4;
110 	gdb_regs[KGDB_REGNUM_R0 +  5] = regs->tf_r5;
111 	gdb_regs[KGDB_REGNUM_R0 +  6] = regs->tf_r6;
112 	gdb_regs[KGDB_REGNUM_R0 +  7] = regs->tf_r7;
113 	gdb_regs[KGDB_REGNUM_R0 +  8] = regs->tf_r8;
114 	gdb_regs[KGDB_REGNUM_R0 +  9] = regs->tf_r9;
115 	gdb_regs[KGDB_REGNUM_R0 + 10] = regs->tf_r10;
116 	gdb_regs[KGDB_REGNUM_R0 + 11] = regs->tf_r11;
117 	gdb_regs[KGDB_REGNUM_R0 + 12] = regs->tf_r12;
118 	gdb_regs[KGDB_REGNUM_R0 + 13] = regs->tf_svc_sp;
119 	gdb_regs[KGDB_REGNUM_R0 + 14] = regs->tf_svc_lr;
120 	gdb_regs[KGDB_REGNUM_R0 + 15] = regs->tf_pc;
121 
122 	gdb_regs[KGDB_REGNUM_SPSR] = regs->tf_spsr;
123 }
124 
125 /*
126  * Reverse the above.
127  */
128 void
129 kgdb_setregs(regs, gdb_regs)
130 	db_regs_t *regs;
131 	kgdb_reg_t *gdb_regs;
132 {
133 	regs->tf_r0     = gdb_regs[KGDB_REGNUM_R0 +  0];
134 	regs->tf_r1     = gdb_regs[KGDB_REGNUM_R0 +  1];
135 	regs->tf_r2     = gdb_regs[KGDB_REGNUM_R0 +  2];
136 	regs->tf_r3     = gdb_regs[KGDB_REGNUM_R0 +  3];
137 	regs->tf_r4     = gdb_regs[KGDB_REGNUM_R0 +  4];
138 	regs->tf_r5     = gdb_regs[KGDB_REGNUM_R0 +  5];
139 	regs->tf_r6     = gdb_regs[KGDB_REGNUM_R0 +  6];
140 	regs->tf_r7     = gdb_regs[KGDB_REGNUM_R0 +  7];
141 	regs->tf_r8     = gdb_regs[KGDB_REGNUM_R0 +  8];
142 	regs->tf_r9     = gdb_regs[KGDB_REGNUM_R0 +  9];
143 	regs->tf_r10    = gdb_regs[KGDB_REGNUM_R0 + 10];
144 	regs->tf_r11    = gdb_regs[KGDB_REGNUM_R0 + 11];
145 	regs->tf_r12    = gdb_regs[KGDB_REGNUM_R0 + 12];
146 	regs->tf_svc_sp = gdb_regs[KGDB_REGNUM_R0 + 13];
147 	regs->tf_svc_lr = gdb_regs[KGDB_REGNUM_R0 + 14];
148 	regs->tf_pc     = gdb_regs[KGDB_REGNUM_R0 + 15];
149 
150 	regs->tf_spsr = gdb_regs[KGDB_REGNUM_SPSR];
151 }
152 
153 /*
154  * Trap into kgdb to wait for debugger to connect,
155  * noting on the console why nothing else is going on.
156  */
157 void
158 kgdb_connect(verbose)
159 	int verbose;
160 {
161 
162 	if (kgdb_dev < 0)
163 		return;
164 
165 	if (verbose)
166 		printf("kgdb waiting...");
167 
168 	asm volatile(KBPT_ASM);
169 
170 	if (verbose)
171 		printf("connected.\n");
172 
173 	kgdb_debug_panic = 1;
174 }
175 
176 /*
177  * Decide what to do on panic.
178  * (This is called by panic, like Debugger())
179  */
180 void
181 kgdb_panic()
182 {
183 
184 	if (kgdb_dev >= 0 && kgdb_debug_panic) {
185 		printf("entering kgdb\n");
186 		kgdb_connect(kgdb_active == 0);
187 	}
188 }
189