xref: /freebsd/sys/arm/arm/db_trace.c (revision b0d29bc47dba79f6f38e67eabadfb4b32ffd9390)
1 /*	$NetBSD: db_trace.c,v 1.8 2003/01/17 22:28:48 thorpej Exp $	*/
2 
3 /*-
4  * Copyright (c) 2000, 2001 Ben Harris
5  * Copyright (c) 1996 Scott K. Stevens
6  *
7  * Mach Operating System
8  * Copyright (c) 1991,1990 Carnegie Mellon University
9  * All Rights Reserved.
10  *
11  * Permission to use, copy, modify and distribute this software and its
12  * documentation is hereby granted, provided that both the copyright
13  * notice and this permission notice appear in all copies of the
14  * software, derivative works or modified versions, and any portions
15  * thereof, and that both notices appear in supporting documentation.
16  *
17  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
18  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
19  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
20  *
21  * Carnegie Mellon requests users of this software to return to
22  *
23  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
24  *  School of Computer Science
25  *  Carnegie Mellon University
26  *  Pittsburgh PA 15213-3890
27  *
28  * any improvements or extensions that they make and grant Carnegie the
29  * rights to redistribute these changes.
30  */
31 #include "opt_ddb.h"
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 
38 
39 #include <sys/proc.h>
40 #include <sys/kdb.h>
41 #include <sys/stack.h>
42 
43 #include <machine/armreg.h>
44 #include <machine/asm.h>
45 #include <machine/cpufunc.h>
46 #include <machine/db_machdep.h>
47 #include <machine/debug_monitor.h>
48 #include <machine/pcb.h>
49 #include <machine/stack.h>
50 #include <machine/vmparam.h>
51 
52 #include <ddb/ddb.h>
53 #include <ddb/db_access.h>
54 #include <ddb/db_sym.h>
55 #include <ddb/db_output.h>
56 
57 static void
58 db_stack_trace_cmd(struct unwind_state *state)
59 {
60 	const char *name;
61 	db_expr_t value;
62 	db_expr_t offset;
63 	c_db_sym_t sym;
64 	u_int reg, i;
65 	char *sep;
66 	uint16_t upd_mask;
67 	bool finished;
68 
69 	finished = false;
70 	while (!finished) {
71 		finished = unwind_stack_one(state, 1);
72 
73 		/* Print the frame details */
74 		sym = db_search_symbol(state->start_pc, DB_STGY_ANY, &offset);
75 		if (sym == C_DB_SYM_NULL) {
76 			value = 0;
77 			name = "(null)";
78 		} else
79 			db_symbol_values(sym, &name, &value);
80 		db_printf("%s() at ", name);
81 		db_printsym(state->start_pc, DB_STGY_PROC);
82 		db_printf("\n");
83 		db_printf("\t pc = 0x%08x  lr = 0x%08x (", state->start_pc,
84 		    state->registers[LR]);
85 		db_printsym(state->registers[LR], DB_STGY_PROC);
86 		db_printf(")\n");
87 		db_printf("\t sp = 0x%08x  fp = 0x%08x",
88 		    state->registers[SP], state->registers[FP]);
89 
90 		/* Don't print the registers we have already printed */
91 		upd_mask = state->update_mask &
92 		    ~((1 << SP) | (1 << FP) | (1 << LR) | (1 << PC));
93 		sep = "\n\t";
94 		for (i = 0, reg = 0; upd_mask != 0; upd_mask >>= 1, reg++) {
95 			if ((upd_mask & 1) != 0) {
96 				db_printf("%s%sr%d = 0x%08x", sep,
97 				    (reg < 10) ? " " : "", reg,
98 				    state->registers[reg]);
99 				i++;
100 				if (i == 2) {
101 					sep = "\n\t";
102 					i = 0;
103 				} else
104 					sep = " ";
105 
106 			}
107 		}
108 		db_printf("\n");
109 
110 		if (finished)
111 			break;
112 
113 		/*
114 		 * Stop if directed to do so, or if we've unwound back to the
115 		 * kernel entry point, or if the unwind function didn't change
116 		 * anything (to avoid getting stuck in this loop forever).
117 		 * If the latter happens, it's an indication that the unwind
118 		 * information is incorrect somehow for the function named in
119 		 * the last frame printed before you see the unwind failure
120 		 * message (maybe it needs a STOP_UNWINDING).
121 		 */
122 		if (state->registers[PC] < VM_MIN_KERNEL_ADDRESS) {
123 			db_printf("Unable to unwind into user mode\n");
124 			finished = true;
125 		} else if (state->update_mask == 0) {
126 			db_printf("Unwind failure (no registers changed)\n");
127 			finished = true;
128 		}
129 	}
130 }
131 
132 void
133 db_md_list_watchpoints(void)
134 {
135 
136 	dbg_show_watchpoint();
137 }
138 
139 int
140 db_md_clr_watchpoint(db_expr_t addr, db_expr_t size)
141 {
142 
143 	return (dbg_remove_watchpoint(addr, size));
144 }
145 
146 int
147 db_md_set_watchpoint(db_expr_t addr, db_expr_t size)
148 {
149 
150 	return (dbg_setup_watchpoint(addr, size, HW_WATCHPOINT_RW));
151 }
152 
153 int
154 db_trace_thread(struct thread *thr, int count)
155 {
156 	struct unwind_state state;
157 	struct pcb *ctx;
158 
159 	if (thr != curthread) {
160 		ctx = kdb_thr_ctx(thr);
161 
162 		state.registers[FP] = ctx->pcb_regs.sf_r11;
163 		state.registers[SP] = ctx->pcb_regs.sf_sp;
164 		state.registers[LR] = ctx->pcb_regs.sf_lr;
165 		state.registers[PC] = ctx->pcb_regs.sf_pc;
166 
167 		db_stack_trace_cmd(&state);
168 	} else
169 		db_trace_self();
170 	return (0);
171 }
172 
173 void
174 db_trace_self(void)
175 {
176 	struct unwind_state state;
177 	uint32_t sp;
178 
179 	/* Read the stack pointer */
180 	__asm __volatile("mov %0, sp" : "=&r" (sp));
181 
182 	state.registers[FP] = (uint32_t)__builtin_frame_address(0);
183 	state.registers[SP] = sp;
184 	state.registers[LR] = (uint32_t)__builtin_return_address(0);
185 	state.registers[PC] = (uint32_t)db_trace_self;
186 
187 	db_stack_trace_cmd(&state);
188 }
189