summaryrefslogtreecommitdiff
path: root/arch/nds32/kernel/traps.c
blob: c0a8f3344fb94f0ff64a43b0829a18d9b4824fc3 (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
// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2005-2017 Andes Technology Corporation

#include <linux/module.h>
#include <linux/personality.h>
#include <linux/kallsyms.h>
#include <linux/hardirq.h>
#include <linux/kdebug.h>
#include <linux/sched/task_stack.h>
#include <linux/uaccess.h>
#include <linux/ftrace.h>

#include <asm/proc-fns.h>
#include <asm/unistd.h>
#include <asm/fpu.h>

#include <linux/ptrace.h>
#include <nds32_intrinsic.h>

extern void show_pte(struct mm_struct *mm, unsigned long addr);

/*
 * Dump out the contents of some memory nicely...
 */
void dump_mem(const char *lvl, unsigned long bottom, unsigned long top)
{
	unsigned long first;
	int i;

	pr_emerg("%s(0x%08lx to 0x%08lx)\n", lvl, bottom, top);

	for (first = bottom & ~31; first < top; first += 32) {
		unsigned long p;
		char str[sizeof(" 12345678") * 8 + 1];

		memset(str, ' ', sizeof(str));
		str[sizeof(str) - 1] = '\0';

		for (p = first, i = 0; i < 8 && p < top; i++, p += 4) {
			if (p >= bottom && p < top) {
				unsigned long val;

				if (get_kernel_nofault(val,
						(unsigned long *)p) == 0)
					sprintf(str + i * 9, " %08lx", val);
				else
					sprintf(str + i * 9, " ????????");
			}
		}
		pr_emerg("%s%04lx:%s\n", lvl, first & 0xffff, str);
	}
}

EXPORT_SYMBOL(dump_mem);

#define LOOP_TIMES (100)
static void __dump(struct task_struct *tsk, unsigned long *base_reg,
		   const char *loglvl)
{
	unsigned long ret_addr;
	int cnt = LOOP_TIMES, graph = 0;
	printk("%sCall Trace:\n", loglvl);
	if (!IS_ENABLED(CONFIG_FRAME_POINTER)) {
		while (!kstack_end(base_reg)) {
			ret_addr = *base_reg++;
			if (__kernel_text_address(ret_addr)) {
				ret_addr = ftrace_graph_ret_addr(
						tsk, &graph, ret_addr, NULL);
				print_ip_sym(loglvl, ret_addr);
			}
			if (--cnt < 0)
				break;
		}
	} else {
		while (!kstack_end((void *)base_reg) &&
		       !((unsigned long)base_reg & 0x3) &&
		       ((unsigned long)base_reg >= TASK_SIZE)) {
			unsigned long next_fp;
			ret_addr = base_reg[LP_OFFSET];
			next_fp = base_reg[FP_OFFSET];
			if (__kernel_text_address(ret_addr)) {

				ret_addr = ftrace_graph_ret_addr(
						tsk, &graph, ret_addr, NULL);
				print_ip_sym(loglvl, ret_addr);
			}
			if (--cnt < 0)
				break;
			base_reg = (unsigned long *)next_fp;
		}
	}
	printk("%s\n", loglvl);
}

void show_stack(struct task_struct *tsk, unsigned long *sp, const char *loglvl)
{
	unsigned long *base_reg;

	if (!tsk)
		tsk = current;
	if (!IS_ENABLED(CONFIG_FRAME_POINTER)) {
		if (tsk != current)
			base_reg = (unsigned long *)(tsk->thread.cpu_context.sp);
		else
			__asm__ __volatile__("\tori\t%0, $sp, #0\n":"=r"(base_reg));
	} else {
		if (tsk != current)
			base_reg = (unsigned long *)(tsk->thread.cpu_context.fp);
		else
			__asm__ __volatile__("\tori\t%0, $fp, #0\n":"=r"(base_reg));
	}
	__dump(tsk, base_reg, loglvl);
	barrier();
}

DEFINE_SPINLOCK(die_lock);

/*
 * This function is protected against re-entrancy.
 */
void __noreturn die(const char *str, struct pt_regs *regs, int err)
{
	struct task_struct *tsk = current;
	static int die_counter;

	console_verbose();
	spin_lock_irq(&die_lock);
	bust_spinlocks(1);

	pr_emerg("Internal error: %s: %x [#%d]\n", str, err, ++die_counter);
	print_modules();
	pr_emerg("CPU: %i\n", smp_processor_id());
	show_regs(regs);
	pr_emerg("Process %s (pid: %d, stack limit = 0x%p)\n",
		 tsk->comm, tsk->pid, end_of_stack(tsk));

	if (!user_mode(regs) || in_interrupt()) {
		dump_mem("Stack: ", regs->sp, (regs->sp + PAGE_SIZE) & PAGE_MASK);
		dump_stack();
	}

	bust_spinlocks(0);
	spin_unlock_irq(&die_lock);
	make_task_dead(SIGSEGV);
}

EXPORT_SYMBOL(die);

void die_if_kernel(const char *str, struct pt_regs *regs, int err)
{
	if (user_mode(regs))
		return;

	die(str, regs, err);
}

int bad_syscall(int n, struct pt_regs *regs)
{
	if (current->personality != PER_LINUX) {
		send_sig(SIGSEGV, current, 1);
		return regs->uregs[0];
	}

	force_sig_fault(SIGILL, ILL_ILLTRP,
			(void __user *)instruction_pointer(regs) - 4);
	die_if_kernel("Oops - bad syscall", regs, n);
	return regs->uregs[0];
}

void __pte_error(const char *file, int line, unsigned long val)
{
	pr_emerg("%s:%d: bad pte %08lx.\n", file, line, val);
}

void __pmd_error(const char *file, int line, unsigned long val)
{
	pr_emerg("%s:%d: bad pmd %08lx.\n", file, line, val);
}

void __pgd_error(const char *file, int line, unsigned long val)
{
	pr_emerg("%s:%d: bad pgd %08lx.\n", file, line, val);
}

extern char *exception_vector, *exception_vector_end;
void __init early_trap_init(void)
{
	unsigned long ivb = 0;
	unsigned long base = PAGE_OFFSET;

	memcpy((unsigned long *)base, (unsigned long *)&exception_vector,
	       ((unsigned long)&exception_vector_end -
		(unsigned long)&exception_vector));
	ivb = __nds32__mfsr(NDS32_SR_IVB);
	/* Check platform support. */
	if (((ivb & IVB_mskNIVIC) >> IVB_offNIVIC) < 2)
		panic
		    ("IVIC mode is not allowed on the platform with interrupt controller\n");
	__nds32__mtsr((ivb & ~IVB_mskESZ) | (IVB_valESZ16 << IVB_offESZ) |
		      IVB_BASE, NDS32_SR_IVB);
	__nds32__mtsr(INT_MASK_INITAIAL_VAL, NDS32_SR_INT_MASK);

	/*
	 * 0x800 = 128 vectors * 16byte.
	 * It should be enough to flush a page.
	 */
	cpu_cache_wbinval_page(base, true);
}

static void send_sigtrap(struct pt_regs *regs, int error_code, int si_code)
{
	struct task_struct *tsk = current;

	tsk->thread.trap_no = ENTRY_DEBUG_RELATED;
	tsk->thread.error_code = error_code;

	force_sig_fault(SIGTRAP, si_code,
			(void __user *)instruction_pointer(regs));
}

void do_debug_trap(unsigned long entry, unsigned long addr,
		   unsigned long type, struct pt_regs *regs)
{
	if (notify_die(DIE_OOPS, "Oops", regs, addr, type, SIGTRAP)
	    == NOTIFY_STOP)
		return;

	if (user_mode(regs)) {
		/* trap_signal */
		send_sigtrap(regs, 0, TRAP_BRKPT);
	} else {
		/* kernel_trap */
		if (!fixup_exception(regs))
			die("unexpected kernel_trap", regs, 0);
	}
}

void unhandled_interruption(struct pt_regs *regs)
{
	pr_emerg("unhandled_interruption\n");
	show_regs(regs);
	if (!user_mode(regs))
		make_task_dead(SIGKILL);
	force_sig(SIGKILL);
}

void unhandled_exceptions(unsigned long entry, unsigned long addr,
			  unsigned long type, struct pt_regs *regs)
{
	pr_emerg("Unhandled Exception: entry: %lx addr:%lx itype:%lx\n", entry,
		 addr, type);
	show_regs(regs);
	if (!user_mode(regs))
		make_task_dead(SIGKILL);
	force_sig(SIGKILL);
}

extern int do_page_fault(unsigned long entry, unsigned long addr,
			 unsigned int error_code, struct pt_regs *regs);

/*
 * 2:DEF dispatch for TLB MISC exception handler
*/

void do_dispatch_tlb_misc(unsigned long entry, unsigned long addr,
			  unsigned long type, struct pt_regs *regs)
{
	type = type & (ITYPE_mskINST | ITYPE_mskETYPE);
	if ((type & ITYPE_mskETYPE) < 5) {
		/* Permission exceptions */
		do_page_fault(entry, addr, type, regs);
	} else
		unhandled_exceptions(entry, addr, type, regs);
}

void do_revinsn(struct pt_regs *regs)
{
	pr_emerg("Reserved Instruction\n");
	show_regs(regs);
	if (!user_mode(regs))
		make_task_dead(SIGILL);
	force_sig(SIGILL);
}

#ifdef CONFIG_ALIGNMENT_TRAP
extern int unalign_access_mode;
extern int do_unaligned_access(unsigned long addr, struct pt_regs *regs);
#endif
void do_dispatch_general(unsigned long entry, unsigned long addr,
			 unsigned long itype, struct pt_regs *regs,
			 unsigned long oipc)
{
	unsigned int swid = itype >> ITYPE_offSWID;
	unsigned long type = itype & (ITYPE_mskINST | ITYPE_mskETYPE);
	if (type == ETYPE_ALIGNMENT_CHECK) {
#ifdef CONFIG_ALIGNMENT_TRAP
		/* Alignment check */
		if (user_mode(regs) && unalign_access_mode) {
			int ret;
			ret = do_unaligned_access(addr, regs);

			if (ret == 0)
				return;

			if (ret == -EFAULT)
				pr_emerg
				    ("Unhandled unaligned access exception\n");
		}
#endif
		do_page_fault(entry, addr, type, regs);
	} else if (type == ETYPE_RESERVED_INSTRUCTION) {
		/* Reserved instruction */
		do_revinsn(regs);
	} else if (type == ETYPE_COPROCESSOR) {
		/* Coprocessor */
#if IS_ENABLED(CONFIG_FPU)
		unsigned int fucop_exist = __nds32__mfsr(NDS32_SR_FUCOP_EXIST);
		unsigned int cpid = ((itype & ITYPE_mskCPID) >> ITYPE_offCPID);

		if ((cpid == FPU_CPID) &&
		    (fucop_exist & FUCOP_EXIST_mskCP0ISFPU)) {
			unsigned int subtype = (itype & ITYPE_mskSTYPE);

			if (true == do_fpu_exception(subtype, regs))
				return;
		}
#endif
		unhandled_exceptions(entry, addr, type, regs);
	} else if (type == ETYPE_TRAP && swid == SWID_RAISE_INTERRUPT_LEVEL) {
		/* trap, used on v3 EDM target debugging workaround */
		/*
		 * DIPC(OIPC) is passed as parameter before
		 * interrupt is enabled, so the DIPC will not be corrupted
		 * even though interrupts are coming in
		 */
		/*
		 * 1. update ipc
		 * 2. update pt_regs ipc with oipc
		 * 3. update pt_regs ipsw (clear DEX)
		 */
		__asm__ volatile ("mtsr %0, $IPC\n\t"::"r" (oipc));
		regs->ipc = oipc;
		if (regs->pipsw & PSW_mskDEX) {
			pr_emerg
			    ("Nested Debug exception is possibly happened\n");
			pr_emerg("ipc:%08x pipc:%08x\n",
				 (unsigned int)regs->ipc,
				 (unsigned int)regs->pipc);
		}
		do_debug_trap(entry, addr, itype, regs);
		regs->ipsw &= ~PSW_mskDEX;
	} else
		unhandled_exceptions(entry, addr, type, regs);
}