1/*	$FreeBSD: releng/10.3/sys/powerpc/powerpc/db_trace.c 236141 2012-05-27 10:25:20Z raj $ */
2/*	$NetBSD: db_trace.c,v 1.20 2002/05/13 20:30:09 matt Exp $	*/
3/*	$OpenBSD: db_trace.c,v 1.3 1997/03/21 02:10:48 niklas Exp $	*/
4
5/*-
6 * Mach Operating System
7 * Copyright (c) 1992 Carnegie Mellon University
8 * All Rights Reserved.
9 *
10 * Permission to use, copy, modify and distribute this software and its
11 * documentation is hereby granted, provided that both the copyright
12 * notice and this permission notice appear in all copies of the
13 * software, derivative works or modified versions, and any portions
14 * thereof, and that both notices appear in supporting documentation.
15 *
16 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
17 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
18 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
19 *
20 * Carnegie Mellon requests users of this software to return to
21 *
22 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
23 *  School of Computer Science
24 *  Carnegie Mellon University
25 *  Pittsburgh PA 15213-3890
26 *
27 * any improvements or extensions that they make and grant Carnegie Mellon
28 * the rights to redistribute these changes.
29 */
30
31#include <sys/param.h>
32#include <sys/systm.h>
33#include <sys/kdb.h>
34#include <sys/proc.h>
35#include <sys/stack.h>
36
37#include <vm/vm.h>
38#include <vm/pmap.h>
39#include <vm/vm_extern.h>
40
41#include <machine/db_machdep.h>
42#include <machine/pcb.h>
43#include <machine/spr.h>
44#include <machine/stack.h>
45#include <machine/trap.h>
46
47#include <ddb/ddb.h>
48#include <ddb/db_access.h>
49#include <ddb/db_sym.h>
50#include <ddb/db_variables.h>
51
52static db_varfcn_t db_frame;
53
54#define DB_OFFSET(x)	(db_expr_t *)offsetof(struct trapframe, x)
55
56#ifdef __powerpc64__
57#define	CALLOFFSET	8	/* Include TOC reload slot */
58#else
59#define	CALLOFFSET	4
60#endif
61
62struct db_variable db_regs[] = {
63	{ "r0",	 DB_OFFSET(fixreg[0]),	db_frame },
64	{ "r1",	 DB_OFFSET(fixreg[1]),	db_frame },
65	{ "r2",	 DB_OFFSET(fixreg[2]),	db_frame },
66	{ "r3",	 DB_OFFSET(fixreg[3]),	db_frame },
67	{ "r4",	 DB_OFFSET(fixreg[4]),	db_frame },
68	{ "r5",	 DB_OFFSET(fixreg[5]),	db_frame },
69	{ "r6",	 DB_OFFSET(fixreg[6]),	db_frame },
70	{ "r7",	 DB_OFFSET(fixreg[7]),	db_frame },
71	{ "r8",	 DB_OFFSET(fixreg[8]),	db_frame },
72	{ "r9",	 DB_OFFSET(fixreg[9]),	db_frame },
73	{ "r10", DB_OFFSET(fixreg[10]),	db_frame },
74	{ "r11", DB_OFFSET(fixreg[11]),	db_frame },
75	{ "r12", DB_OFFSET(fixreg[12]),	db_frame },
76	{ "r13", DB_OFFSET(fixreg[13]),	db_frame },
77	{ "r14", DB_OFFSET(fixreg[14]),	db_frame },
78	{ "r15", DB_OFFSET(fixreg[15]),	db_frame },
79	{ "r16", DB_OFFSET(fixreg[16]),	db_frame },
80	{ "r17", DB_OFFSET(fixreg[17]),	db_frame },
81	{ "r18", DB_OFFSET(fixreg[18]),	db_frame },
82	{ "r19", DB_OFFSET(fixreg[19]),	db_frame },
83	{ "r20", DB_OFFSET(fixreg[20]),	db_frame },
84	{ "r21", DB_OFFSET(fixreg[21]),	db_frame },
85	{ "r22", DB_OFFSET(fixreg[22]),	db_frame },
86	{ "r23", DB_OFFSET(fixreg[23]),	db_frame },
87	{ "r24", DB_OFFSET(fixreg[24]),	db_frame },
88	{ "r25", DB_OFFSET(fixreg[25]),	db_frame },
89	{ "r26", DB_OFFSET(fixreg[26]),	db_frame },
90	{ "r27", DB_OFFSET(fixreg[27]),	db_frame },
91	{ "r28", DB_OFFSET(fixreg[28]),	db_frame },
92	{ "r29", DB_OFFSET(fixreg[29]),	db_frame },
93	{ "r30", DB_OFFSET(fixreg[30]),	db_frame },
94	{ "r31", DB_OFFSET(fixreg[31]),	db_frame },
95	{ "srr0", DB_OFFSET(srr0),	db_frame },
96	{ "srr1", DB_OFFSET(srr1),	db_frame },
97	{ "lr",	 DB_OFFSET(lr),		db_frame },
98	{ "ctr", DB_OFFSET(ctr),	db_frame },
99	{ "cr",	 DB_OFFSET(cr),		db_frame },
100	{ "xer", DB_OFFSET(xer),	db_frame },
101#ifdef AIM
102	{ "dar", DB_OFFSET(cpu.aim.dar),	db_frame },
103	{ "dsisr", DB_OFFSET(cpu.aim.dsisr),	db_frame },
104#endif
105#if defined(BOOKE)
106	{ "dear", DB_OFFSET(cpu.booke.dear),	db_frame },
107	{ "esr", DB_OFFSET(cpu.booke.esr),	db_frame },
108#endif
109};
110struct db_variable *db_eregs = db_regs + sizeof (db_regs)/sizeof (db_regs[0]);
111
112/*
113 * register variable handling
114 */
115static int
116db_frame(struct db_variable *vp, db_expr_t *valuep, int op)
117{
118	register_t *reg;
119
120	if (kdb_frame == NULL)
121		return (0);
122        reg = (register_t*)((uintptr_t)kdb_frame + (uintptr_t)vp->valuep);
123        if (op == DB_VAR_GET)
124                *valuep = *reg;
125        else
126                *reg = *valuep;
127        return (1);
128}
129
130
131/*
132 *	Frame tracing.
133 */
134static int
135db_backtrace(struct thread *td, db_addr_t fp, int count)
136{
137	db_addr_t stackframe, lr, *args;
138	db_expr_t diff;
139	c_db_sym_t sym;
140	const char *symname;
141	boolean_t kernel_only = TRUE;
142	boolean_t full = FALSE;
143
144#if 0
145	{
146		register char *cp = modif;
147		register char c;
148
149		while ((c = *cp++) != 0) {
150			if (c == 't')
151				trace_thread = TRUE;
152			if (c == 'u')
153				kernel_only = FALSE;
154			if (c == 'f')
155				full = TRUE;
156		}
157	}
158#endif
159
160	stackframe = fp;
161
162	while (!db_pager_quit) {
163		if (stackframe < PAGE_SIZE)
164			break;
165
166		/*
167		 * Locate the next frame by grabbing the backchain ptr
168		 * from frame[0]
169		 */
170		stackframe = *(db_addr_t *)stackframe;
171
172	next_frame:
173	    #ifdef __powerpc64__
174		/* The saved arg values start at frame[6] */
175		args = (db_addr_t *)(stackframe + 48);
176	    #else
177		/* The saved arg values start at frame[2] */
178		args = (db_addr_t *)(stackframe + 8);
179	    #endif
180
181		if (stackframe < PAGE_SIZE)
182			break;
183
184	        if (count-- == 0)
185			break;
186
187		/*
188		 * Extract link register from frame and subtract
189		 * 4 to convert into calling address (as opposed to
190		 * return address)
191		 */
192	    #ifdef __powerpc64__
193		lr = *(db_addr_t *)(stackframe + 16) - 4;
194	    #else
195		lr = *(db_addr_t *)(stackframe + 4) - 4;
196	    #endif
197		if ((lr & 3) || (lr < 0x100)) {
198			db_printf("saved LR(0x%zx) is invalid.", lr);
199			break;
200		}
201
202		#ifdef __powerpc64__
203		db_printf("0x%016lx: ", stackframe);
204		#else
205		db_printf("0x%08x: ", stackframe);
206		#endif
207
208		/*
209		 * The trap code labels the return addresses from the
210		 * call to C code as 'trapexit' and 'asttrapexit. Use this
211		 * to determine if the callframe has to traverse a saved
212		 * trap context
213		 */
214		if ((lr + CALLOFFSET == (db_addr_t) &trapexit) ||
215		    (lr + CALLOFFSET == (db_addr_t) &asttrapexit)) {
216			const char *trapstr;
217			struct trapframe *tf = (struct trapframe *)(args);
218			db_printf("%s ", tf->srr1 & PSL_PR ? "user" : "kernel");
219			switch (tf->exc) {
220			case EXC_DSI:
221				/* XXX take advantage of the union. */
222				db_printf("DSI %s trap @ %#zx by ",
223				    (tf->cpu.aim.dsisr & DSISR_STORE) ? "write"
224				    : "read", tf->cpu.aim.dar);
225				goto print_trap;
226			case EXC_ALI:
227				/* XXX take advantage of the union. */
228				db_printf("ALI trap @ %#zx (xSR %#x) ",
229				    tf->cpu.aim.dar,
230				    (uint32_t)tf->cpu.aim.dsisr);
231				goto print_trap;
232#ifdef __powerpc64__
233			case EXC_DSE:
234				db_printf("DSE trap @ %#zx by ",
235				    tf->cpu.aim.dar);
236				goto print_trap;
237			case EXC_ISE:
238				db_printf("ISE trap @ %#zx by ", tf->srr0);
239				goto print_trap;
240#endif
241			case EXC_ISI: trapstr = "ISI"; break;
242			case EXC_PGM: trapstr = "PGM"; break;
243			case EXC_SC: trapstr = "SC"; break;
244			case EXC_EXI: trapstr = "EXI"; break;
245			case EXC_MCHK: trapstr = "MCHK"; break;
246#if !defined(BOOKE)
247			case EXC_VEC: trapstr = "VEC"; break;
248			case EXC_FPA: trapstr = "FPA"; break;
249			case EXC_BPT: trapstr = "BPT"; break;
250			case EXC_TRC: trapstr = "TRC"; break;
251			case EXC_RUNMODETRC: trapstr = "RUNMODETRC"; break;
252			case EXC_SMI: trapstr = "SMI"; break;
253			case EXC_RST: trapstr = "RST"; break;
254#endif
255			case EXC_FPU: trapstr = "FPU"; break;
256			case EXC_DECR: trapstr = "DECR"; break;
257			case EXC_PERF: trapstr = "PERF"; break;
258			default: trapstr = NULL; break;
259			}
260			if (trapstr != NULL) {
261				db_printf("%s trap by ", trapstr);
262			} else {
263				db_printf("trap %#zx by ", tf->exc);
264			}
265
266		   print_trap:
267			lr = (db_addr_t) tf->srr0;
268			diff = 0;
269			symname = NULL;
270			sym = db_search_symbol(lr, DB_STGY_ANY, &diff);
271			db_symbol_values(sym, &symname, 0);
272			if (symname == NULL || !strcmp(symname, "end")) {
273				db_printf("%#zx: srr1=%#zx\n", lr, tf->srr1);
274			} else {
275				db_printf("%s+%#zx: srr1=%#zx\n", symname, diff,
276				    tf->srr1);
277			}
278			db_printf("%-10s  r1=%#zx cr=%#x xer=%#x ctr=%#zx",
279			    "", tf->fixreg[1], (uint32_t)tf->cr,
280			    (uint32_t)tf->xer, tf->ctr);
281			if (tf->exc == EXC_DSI)
282				db_printf(" sr=%#x",
283				    (uint32_t)tf->cpu.aim.dsisr);
284			db_printf("\n");
285			stackframe = (db_addr_t) tf->fixreg[1];
286			if (kernel_only && (tf->srr1 & PSL_PR))
287				break;
288			goto next_frame;
289		}
290
291		diff = 0;
292		symname = NULL;
293		sym = db_search_symbol(lr, DB_STGY_ANY, &diff);
294		db_symbol_values(sym, &symname, 0);
295		if (symname == NULL || !strcmp(symname, "end"))
296			db_printf("at %zx", lr);
297		else
298			db_printf("at %s+%#zx", symname, diff);
299		if (full)
300			/* Print all the args stored in that stackframe. */
301			db_printf("(%zx, %zx, %zx, %zx, %zx, %zx, %zx, %zx)",
302				args[0], args[1], args[2], args[3],
303				args[4], args[5], args[6], args[7]);
304		db_printf("\n");
305	}
306
307	return (0);
308}
309
310void
311db_trace_self(void)
312{
313	db_addr_t addr;
314
315	addr = (db_addr_t)__builtin_frame_address(1);
316	db_backtrace(curthread, addr, -1);
317}
318
319int
320db_trace_thread(struct thread *td, int count)
321{
322	struct pcb *ctx;
323
324	ctx = kdb_thr_ctx(td);
325	return (db_backtrace(td, (db_addr_t)ctx->pcb_sp, count));
326}
327