summaryrefslogtreecommitdiff
path: root/arch/ppc/cpu/mpc8xx/traps.c
blob: 6efe8e0ea7bc49166734bceef60fb97902171256 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
/*
 * linux/arch/ppc/kernel/traps.c
 *
 * Copyright (C) 1995-1996  Gary Thomas (gdt@linuxppc.org)
 *
 * Modified by Cort Dougan (cort@cs.nmt.edu)
 * and Paul Mackerras (paulus@cs.anu.edu.au)
 *
 * (C) Copyright 2000
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */

/*
 * This file handles the architecture-dependent parts of hardware exceptions
 */

#include <common.h>
#include <command.h>
#include <kgdb.h>
#include <asm/processor.h>

#if defined(CONFIG_CMD_BEDBUG)
extern void do_bedbug_breakpoint(struct pt_regs *);
#endif

/* Returns 0 if exception not found and fixup otherwise.  */
extern unsigned long search_exception_table(unsigned long);

/* THIS NEEDS CHANGING to use the board info structure.
*/
#define END_OF_MEM	0x02000000

/*
 * Trap & Exception support
 */

void
print_backtrace(unsigned long *sp)
{
	int cnt = 0;
	unsigned long i;

	printf("Call backtrace: ");
	while (sp) {
		if ((uint)sp > END_OF_MEM)
			break;

		i = sp[1];
		if (cnt++ % 7 == 0)
			printf("\n");
		printf("%08lX ", i);
		if (cnt > 32) break;
		sp = (unsigned long *)*sp;
	}
	printf("\n");
}

void show_regs(struct pt_regs * regs)
{
	int i;

	printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n",
	       regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
	printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n",
	       regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
	       regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0,
	       regs->msr&MSR_IR ? 1 : 0,
	       regs->msr&MSR_DR ? 1 : 0);

	printf("\n");
	for (i = 0;  i < 32;  i++) {
		if ((i % 8) == 0)
		{
			printf("GPR%02d: ", i);
		}

		printf("%08lX ", regs->gpr[i]);
		if ((i % 8) == 7)
		{
			printf("\n");
		}
	}
}


void
_exception(int signr, struct pt_regs *regs)
{
	show_regs(regs);
	print_backtrace((unsigned long *)regs->gpr[1]);
	panic("Exception in kernel pc %lx signal %d",regs->nip,signr);
}

void
MachineCheckException(struct pt_regs *regs)
{
	unsigned long fixup;

	/* Probing PCI using config cycles cause this exception
	 * when a device is not present.  Catch it and return to
	 * the PCI exception handler.
	 */
	if ((fixup = search_exception_table(regs->nip)) != 0) {
		regs->nip = fixup;
		return;
	}

#if defined(CONFIG_CMD_KGDB)
	if (debugger_exception_handler && (*debugger_exception_handler)(regs))
		return;
#endif

	printf("Machine check in kernel mode.\n");
	printf("Caused by (from msr): ");
	printf("regs %p ",regs);
	switch( regs->msr & 0x000F0000) {
	case (0x80000000>>12):
		printf("Machine check signal - probably due to mm fault\n"
			"with mmu off\n");
		break;
	case (0x80000000>>13):
		printf("Transfer error ack signal\n");
		break;
	case (0x80000000>>14):
		printf("Data parity signal\n");
		break;
	case (0x80000000>>15):
		printf("Address parity signal\n");
		break;
	default:
		printf("Unknown values in msr\n");
	}
	show_regs(regs);
	print_backtrace((unsigned long *)regs->gpr[1]);
	panic("machine check");
}

void
AlignmentException(struct pt_regs *regs)
{
#if defined(CONFIG_CMD_KGDB)
	if (debugger_exception_handler && (*debugger_exception_handler)(regs))
		return;
#endif
	show_regs(regs);
	print_backtrace((unsigned long *)regs->gpr[1]);
	panic("Alignment Exception");
}

void
ProgramCheckException(struct pt_regs *regs)
{
#if defined(CONFIG_CMD_KGDB)
	if (debugger_exception_handler && (*debugger_exception_handler)(regs))
		return;
#endif
	show_regs(regs);
	print_backtrace((unsigned long *)regs->gpr[1]);
	panic("Program Check Exception");
}

void
SoftEmuException(struct pt_regs *regs)
{
#if defined(CONFIG_CMD_KGDB)
	if (debugger_exception_handler && (*debugger_exception_handler)(regs))
		return;
#endif
	show_regs(regs);
	print_backtrace((unsigned long *)regs->gpr[1]);
	panic("Software Emulation Exception");
}


void
UnknownException(struct pt_regs *regs)
{
#if defined(CONFIG_CMD_KGDB)
	if (debugger_exception_handler && (*debugger_exception_handler)(regs))
		return;
#endif
	printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
	       regs->nip, regs->msr, regs->trap);
	_exception(0, regs);
}

void
DebugException(struct pt_regs *regs)
{
  printf("Debugger trap at @ %lx\n", regs->nip );
  show_regs(regs);
#if defined(CONFIG_CMD_BEDBUG)
  do_bedbug_breakpoint( regs );
#endif
}

/* Probe an address by reading.  If not present, return -1, otherwise
 * return 0.
 */
int
addr_probe(uint *addr)
{
#if 0
	int	retval;

	__asm__ __volatile__(			\
		"1:	lwz %0,0(%1)\n"		\
		"	eieio\n"		\
		"	li %0,0\n"		\
		"2:\n"				\
		".section .fixup,\"ax\"\n"	\
		"3:	li %0,-1\n"		\
		"	b 2b\n"			\
		".section __ex_table,\"a\"\n"	\
		"	.align 2\n"		\
		"	.long 1b,3b\n"		\
		".text"				\
		: "=r" (retval) : "r"(addr));

	return (retval);
#endif
	return 0;
}