summaryrefslogtreecommitdiff
path: root/arch/frv/kernel/traps.c
blob: 98ce3628ebde54a9c9aae2fa46cd49671ac9c848 (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
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
/* traps.c: high-level exception handler for FR-V
 *
 * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * 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.
 */

#include <linux/sched.h>
#include <linux/signal.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/types.h>
#include <linux/user.h>
#include <linux/string.h>
#include <linux/linkage.h>
#include <linux/init.h>
#include <linux/module.h>

#include <asm/setup.h>
#include <asm/fpu.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/siginfo.h>
#include <asm/unaligned.h>

void show_backtrace(struct pt_regs *, unsigned long);

extern asmlinkage void __break_hijack_kernel_event(void);

/*****************************************************************************/
/*
 * instruction access error
 */
asmlinkage void insn_access_error(unsigned long esfr1, unsigned long epcr0, unsigned long esr0)
{
	siginfo_t info;

	die_if_kernel("-- Insn Access Error --\n"
		      "EPCR0 : %08lx\n"
		      "ESR0  : %08lx\n",
		      epcr0, esr0);

	info.si_signo	= SIGSEGV;
	info.si_code	= SEGV_ACCERR;
	info.si_errno	= 0;
	info.si_addr	= (void *) ((epcr0 & EPCR0_V) ? (epcr0 & EPCR0_PC) : __frame->pc);

	force_sig_info(info.si_signo, &info, current);
} /* end insn_access_error() */

/*****************************************************************************/
/*
 * handler for:
 * - illegal instruction
 * - privileged instruction
 * - unsupported trap
 * - debug exceptions
 */
asmlinkage void illegal_instruction(unsigned long esfr1, unsigned long epcr0, unsigned long esr0)
{
	siginfo_t info;

	die_if_kernel("-- Illegal Instruction --\n"
		      "EPCR0 : %08lx\n"
		      "ESR0  : %08lx\n"
		      "ESFR1 : %08lx\n",
		      epcr0, esr0, esfr1);

	info.si_errno	= 0;
	info.si_addr	= (void *) ((epcr0 & EPCR0_PC) ? (epcr0 & EPCR0_PC) : __frame->pc);

	switch (__frame->tbr & TBR_TT) {
	case TBR_TT_ILLEGAL_INSTR:
		info.si_signo	= SIGILL;
		info.si_code	= ILL_ILLOPC;
		break;
	case TBR_TT_PRIV_INSTR:
		info.si_signo	= SIGILL;
		info.si_code	= ILL_PRVOPC;
		break;
	case TBR_TT_TRAP2 ... TBR_TT_TRAP126:
		info.si_signo	= SIGILL;
		info.si_code	= ILL_ILLTRP;
		break;
	/* GDB uses "tira gr0, #1" as a breakpoint instruction.  */
	case TBR_TT_TRAP1:
	case TBR_TT_BREAK:
		info.si_signo	= SIGTRAP;
		info.si_code	=
			(__frame->__status & REG__STATUS_STEPPED) ? TRAP_TRACE : TRAP_BRKPT;
		break;
	}

	force_sig_info(info.si_signo, &info, current);
} /* end illegal_instruction() */

/*****************************************************************************/
/*
 *
 */
asmlinkage void media_exception(unsigned long msr0, unsigned long msr1)
{
	siginfo_t info;

	die_if_kernel("-- Media Exception --\n"
		      "MSR0 : %08lx\n"
		      "MSR1 : %08lx\n",
		      msr0, msr1);

	info.si_signo	= SIGFPE;
	info.si_code	= FPE_MDAOVF;
	info.si_errno	= 0;
	info.si_addr	= (void *) __frame->pc;

	force_sig_info(info.si_signo, &info, current);
} /* end media_exception() */

/*****************************************************************************/
/*
 * instruction or data access exception
 */
asmlinkage void memory_access_exception(unsigned long esr0,
					unsigned long ear0,
					unsigned long epcr0)
{
	siginfo_t info;

#ifdef CONFIG_MMU
	unsigned long fixup;

	if ((esr0 & ESRx_EC) == ESRx_EC_DATA_ACCESS)
		if (handle_misalignment(esr0, ear0, epcr0) == 0)
			return;

	if ((fixup = search_exception_table(__frame->pc)) != 0) {
		__frame->pc = fixup;
		return;
	}
#endif

	die_if_kernel("-- Memory Access Exception --\n"
		      "ESR0  : %08lx\n"
		      "EAR0  : %08lx\n"
		      "EPCR0 : %08lx\n",
		      esr0, ear0, epcr0);

	info.si_signo	= SIGSEGV;
	info.si_code	= SEGV_ACCERR;
	info.si_errno	= 0;
	info.si_addr	= NULL;

	if ((esr0 & (ESRx_VALID | ESR0_EAV)) == (ESRx_VALID | ESR0_EAV))
		info.si_addr = (void *) ear0;

	force_sig_info(info.si_signo, &info, current);

} /* end memory_access_exception() */

/*****************************************************************************/
/*
 * data access error
 * - double-word data load from CPU control area (0xFExxxxxx)
 * - read performed on inactive or self-refreshing SDRAM
 * - error notification from slave device
 * - misaligned address
 * - access to out of bounds memory region
 * - user mode accessing privileged memory region
 * - write to R/O memory region
 */
asmlinkage void data_access_error(unsigned long esfr1, unsigned long esr15, unsigned long ear15)
{
	siginfo_t info;

	die_if_kernel("-- Data Access Error --\n"
		      "ESR15 : %08lx\n"
		      "EAR15 : %08lx\n",
		      esr15, ear15);

	info.si_signo	= SIGSEGV;
	info.si_code	= SEGV_ACCERR;
	info.si_errno	= 0;
	info.si_addr	= (void *)
		(((esr15 & (ESRx_VALID|ESR15_EAV)) == (ESRx_VALID|ESR15_EAV)) ? ear15 : 0);

	force_sig_info(info.si_signo, &info, current);
} /* end data_access_error() */

/*****************************************************************************/
/*
 * data store error - should only happen if accessing inactive or self-refreshing SDRAM
 */
asmlinkage void data_store_error(unsigned long esfr1, unsigned long esr15)
{
	die_if_kernel("-- Data Store Error --\n"
		      "ESR15 : %08lx\n",
		      esr15);
	BUG();
} /* end data_store_error() */

/*****************************************************************************/
/*
 *
 */
asmlinkage void division_exception(unsigned long esfr1, unsigned long esr0, unsigned long isr)
{
	siginfo_t info;

	die_if_kernel("-- Division Exception --\n"
		      "ESR0 : %08lx\n"
		      "ISR  : %08lx\n",
		      esr0, isr);

	info.si_signo	= SIGFPE;
	info.si_code	= FPE_INTDIV;
	info.si_errno	= 0;
	info.si_addr	= (void *) __frame->pc;

	force_sig_info(info.si_signo, &info, current);
} /* end division_exception() */

/*****************************************************************************/
/*
 *
 */
asmlinkage void compound_exception(unsigned long esfr1,
				   unsigned long esr0, unsigned long esr14, unsigned long esr15,
				   unsigned long msr0, unsigned long msr1)
{
	die_if_kernel("-- Compound Exception --\n"
		      "ESR0  : %08lx\n"
		      "ESR15 : %08lx\n"
		      "ESR15 : %08lx\n"
		      "MSR0  : %08lx\n"
		      "MSR1  : %08lx\n",
		      esr0, esr14, esr15, msr0, msr1);
	BUG();
} /* end compound_exception() */

/*****************************************************************************/
/*
 * The architecture-independent backtrace generator
 */
void dump_stack(void)
{
	show_stack(NULL, NULL);
}

EXPORT_SYMBOL(dump_stack);

void show_stack(struct task_struct *task, unsigned long *sp)
{
}

void show_trace_task(struct task_struct *tsk)
{
	printk("CONTEXT: stack=0x%lx frame=0x%p LR=0x%lx RET=0x%lx\n",
	       tsk->thread.sp, tsk->thread.frame, tsk->thread.lr, tsk->thread.sched_lr);
}

static const char *regnames[] = {
	"PSR ", "ISR ", "CCR ", "CCCR",
	"LR  ", "LCR ", "PC  ", "_stt",
	"sys ", "GR8*", "GNE0", "GNE1",
	"IACH", "IACL",
	"TBR ", "SP  ", "FP  ", "GR3 ",
	"GR4 ", "GR5 ", "GR6 ", "GR7 ",
	"GR8 ", "GR9 ", "GR10", "GR11",
	"GR12", "GR13", "GR14", "GR15",
	"GR16", "GR17", "GR18", "GR19",
	"GR20", "GR21", "GR22", "GR23",
	"GR24", "GR25", "GR26", "GR27",
	"EFRM", "CURR", "GR30", "BFRM"
};

void show_regs(struct pt_regs *regs)
{
	uint32_t *reg;
	int loop;

	printk("\n");

	printk("Frame: @%08x [%s]\n",
	       (uint32_t) regs,
	       regs->psr & PSR_S ? "kernel" : "user");

	reg = (uint32_t *) regs;
	for (loop = 0; loop < REG__END; loop++) {
		printk("%s %08x", regnames[loop + 0], reg[loop + 0]);

		if (loop == REG__END - 1 || loop % 5 == 4)
			printk("\n");
		else
			printk(" | ");
	}

	printk("Process %s (pid: %d)\n", current->comm, current->pid);
}

void die_if_kernel(const char *str, ...)
{
	char buffer[256];
	va_list va;

	if (user_mode(__frame))
		return;

	va_start(va, str);
	vsprintf(buffer, str, va);
	va_end(va);

	console_verbose();
	printk("\n===================================\n");
	printk("%s\n", buffer);
	show_backtrace(__frame, 0);

	__break_hijack_kernel_event();
	do_exit(SIGSEGV);
}

/*****************************************************************************/
/*
 * dump the contents of an exception frame
 */
static void show_backtrace_regs(struct pt_regs *frame)
{
	uint32_t *reg;
	int loop;

	/* print the registers for this frame */
	printk("<-- %s Frame: @%p -->\n",
	       frame->psr & PSR_S ? "Kernel Mode" : "User Mode",
	       frame);

	reg = (uint32_t *) frame;
	for (loop = 0; loop < REG__END; loop++) {
		printk("%s %08x", regnames[loop + 0], reg[loop + 0]);

		if (loop == REG__END - 1 || loop % 5 == 4)
			printk("\n");
		else
			printk(" | ");
	}

	printk("--------\n");
} /* end show_backtrace_regs() */

/*****************************************************************************/
/*
 * generate a backtrace of the kernel stack
 */
void show_backtrace(struct pt_regs *frame, unsigned long sp)
{
	struct pt_regs *frame0;
	unsigned long tos = 0, stop = 0, base;
	int format;

	base = ((((unsigned long) frame) + 8191) & ~8191) - sizeof(struct user_context);
	frame0 = (struct pt_regs *) base;

	if (sp) {
		tos = sp;
		stop = (unsigned long) frame;
	}

	printk("\nProcess %s (pid: %d)\n\n", current->comm, current->pid);

	for (;;) {
		/* dump stack segment between frames */
		//printk("%08lx -> %08lx\n", tos, stop);
		format = 0;
		while (tos < stop) {
			if (format == 0)
				printk(" %04lx :", tos & 0xffff);

			printk(" %08lx", *(unsigned long *) tos);

			tos += 4;
			format++;
			if (format == 8) {
				printk("\n");
				format = 0;
			}
		}

		if (format > 0)
			printk("\n");

		/* dump frame 0 outside of the loop */
		if (frame == frame0)
			break;

		tos = frame->sp;
		if (((unsigned long) frame) + sizeof(*frame) != tos) {
			printk("-- TOS %08lx does not follow frame %p --\n",
			       tos, frame);
			break;
		}

		show_backtrace_regs(frame);

		/* dump the stack between this frame and the next */
		stop = (unsigned long) frame->next_frame;
		if (stop != base &&
		    (stop < tos ||
		     stop > base ||
		     (stop < base && stop + sizeof(*frame) > base) ||
		     stop & 3)) {
			printk("-- next_frame %08lx is invalid (range %08lx-%08lx) --\n",
			       stop, tos, base);
			break;
		}

		/* move to next frame */
		frame = frame->next_frame;
	}

	/* we can always dump frame 0, even if the rest of the stack is corrupt */
	show_backtrace_regs(frame0);

} /* end show_backtrace() */

/*****************************************************************************/
/*
 * initialise traps
 */
void __init trap_init (void)
{
} /* end trap_init() */