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26#include <linux/kernel.h>
27#include <linux/sched.h>
28#include <linux/init.h>
29#include <linux/module.h>
30#include <linux/stringify.h>
31#include <linux/kallsyms.h>
32#include <linux/delay.h>
33#include <linux/hardirq.h>
34
35#include <asm/ptrace.h>
36#include <asm/timex.h>
37#include <asm/uaccess.h>
38#include <asm/pgtable.h>
39#include <asm/processor.h>
40
41#ifdef CONFIG_KGDB
42extern int gdb_enter;
43extern int return_from_debug_flag;
44#endif
45
46
47
48
49
50extern void kernel_exception(void);
51extern void user_exception(void);
52
53extern void fast_syscall_kernel(void);
54extern void fast_syscall_user(void);
55extern void fast_alloca(void);
56extern void fast_unaligned(void);
57extern void fast_second_level_miss(void);
58extern void fast_store_prohibited(void);
59extern void fast_coprocessor(void);
60
61extern void do_illegal_instruction (struct pt_regs*);
62extern void do_interrupt (struct pt_regs*);
63extern void do_unaligned_user (struct pt_regs*);
64extern void do_multihit (struct pt_regs*, unsigned long);
65extern void do_page_fault (struct pt_regs*, unsigned long);
66extern void do_debug (struct pt_regs*);
67extern void system_call (struct pt_regs*);
68
69
70
71
72
73
74
75#define KRNL 0x01
76#define USER 0x02
77
78#define COPROCESSOR(x) \
79{ EXCCAUSE_COPROCESSOR ## x ## _DISABLED, USER, fast_coprocessor }
80
81typedef struct {
82 int cause;
83 int fast;
84 void* handler;
85} dispatch_init_table_t;
86
87static dispatch_init_table_t __initdata dispatch_init_table[] = {
88
89{ EXCCAUSE_ILLEGAL_INSTRUCTION, 0, do_illegal_instruction},
90{ EXCCAUSE_SYSTEM_CALL, KRNL, fast_syscall_kernel },
91{ EXCCAUSE_SYSTEM_CALL, USER, fast_syscall_user },
92{ EXCCAUSE_SYSTEM_CALL, 0, system_call },
93
94
95{ EXCCAUSE_LEVEL1_INTERRUPT, 0, do_interrupt },
96{ EXCCAUSE_ALLOCA, USER|KRNL, fast_alloca },
97
98
99#if XCHAL_UNALIGNED_LOAD_EXCEPTION || XCHAL_UNALIGNED_STORE_EXCEPTION
100#ifdef CONFIG_UNALIGNED_USER
101{ EXCCAUSE_UNALIGNED, USER, fast_unaligned },
102#else
103{ EXCCAUSE_UNALIGNED, 0, do_unaligned_user },
104#endif
105{ EXCCAUSE_UNALIGNED, KRNL, fast_unaligned },
106#endif
107#ifdef CONFIG_MMU
108{ EXCCAUSE_ITLB_MISS, 0, do_page_fault },
109{ EXCCAUSE_ITLB_MISS, USER|KRNL, fast_second_level_miss},
110{ EXCCAUSE_ITLB_MULTIHIT, 0, do_multihit },
111{ EXCCAUSE_ITLB_PRIVILEGE, 0, do_page_fault },
112
113{ EXCCAUSE_FETCH_CACHE_ATTRIBUTE, 0, do_page_fault },
114{ EXCCAUSE_DTLB_MISS, USER|KRNL, fast_second_level_miss},
115{ EXCCAUSE_DTLB_MISS, 0, do_page_fault },
116{ EXCCAUSE_DTLB_MULTIHIT, 0, do_multihit },
117{ EXCCAUSE_DTLB_PRIVILEGE, 0, do_page_fault },
118
119{ EXCCAUSE_STORE_CACHE_ATTRIBUTE, USER|KRNL, fast_store_prohibited },
120{ EXCCAUSE_STORE_CACHE_ATTRIBUTE, 0, do_page_fault },
121{ EXCCAUSE_LOAD_CACHE_ATTRIBUTE, 0, do_page_fault },
122#endif
123
124#if XTENSA_HAVE_COPROCESSOR(0)
125COPROCESSOR(0),
126#endif
127#if XTENSA_HAVE_COPROCESSOR(1)
128COPROCESSOR(1),
129#endif
130#if XTENSA_HAVE_COPROCESSOR(2)
131COPROCESSOR(2),
132#endif
133#if XTENSA_HAVE_COPROCESSOR(3)
134COPROCESSOR(3),
135#endif
136#if XTENSA_HAVE_COPROCESSOR(4)
137COPROCESSOR(4),
138#endif
139#if XTENSA_HAVE_COPROCESSOR(5)
140COPROCESSOR(5),
141#endif
142#if XTENSA_HAVE_COPROCESSOR(6)
143COPROCESSOR(6),
144#endif
145#if XTENSA_HAVE_COPROCESSOR(7)
146COPROCESSOR(7),
147#endif
148{ EXCCAUSE_MAPPED_DEBUG, 0, do_debug },
149{ -1, -1, 0 }
150
151};
152
153
154
155
156
157
158unsigned long exc_table[EXC_TABLE_SIZE/4];
159
160void die(const char*, struct pt_regs*, long);
161
162static inline void
163__die_if_kernel(const char *str, struct pt_regs *regs, long err)
164{
165 if (!user_mode(regs))
166 die(str, regs, err);
167}
168
169
170
171
172
173void do_unhandled(struct pt_regs *regs, unsigned long exccause)
174{
175 __die_if_kernel("Caught unhandled exception - should not happen",
176 regs, SIGKILL);
177
178
179 printk("Caught unhandled exception in '%s' "
180 "(pid = %d, pc = %#010lx) - should not happen\n"
181 "\tEXCCAUSE is %ld\n",
182 current->comm, task_pid_nr(current), regs->pc, exccause);
183 force_sig(SIGILL, current);
184}
185
186
187
188
189
190void do_multihit(struct pt_regs *regs, unsigned long exccause)
191{
192 die("Caught multihit exception", regs, SIGKILL);
193}
194
195
196
197
198
199
200unsigned long ignored_level1_interrupts;
201extern void do_IRQ(int, struct pt_regs *);
202
203void do_interrupt (struct pt_regs *regs)
204{
205 unsigned long intread = get_sr (INTREAD);
206 unsigned long intenable = get_sr (INTENABLE);
207 int i, mask;
208
209
210
211
212
213
214 for (i=0, mask = 1; i < XCHAL_NUM_INTERRUPTS; i++, mask <<= 1) {
215 if (mask & (intread & intenable)) {
216 set_sr (mask, INTCLEAR);
217 do_IRQ (i,regs);
218 }
219 }
220}
221
222
223
224
225
226void
227do_illegal_instruction(struct pt_regs *regs)
228{
229 __die_if_kernel("Illegal instruction in kernel", regs, SIGKILL);
230
231
232
233 printk("Illegal Instruction in '%s' (pid = %d, pc = %#010lx)\n",
234 current->comm, task_pid_nr(current), regs->pc);
235 force_sig(SIGILL, current);
236}
237
238
239
240
241
242
243
244
245
246#if XCHAL_UNALIGNED_LOAD_EXCEPTION || XCHAL_UNALIGNED_STORE_EXCEPTION
247#ifndef CONFIG_UNALIGNED_USER
248void
249do_unaligned_user (struct pt_regs *regs)
250{
251 siginfo_t info;
252
253 __die_if_kernel("Unhandled unaligned exception in kernel",
254 regs, SIGKILL);
255
256 current->thread.bad_vaddr = regs->excvaddr;
257 current->thread.error_code = -3;
258 printk("Unaligned memory access to %08lx in '%s' "
259 "(pid = %d, pc = %#010lx)\n",
260 regs->excvaddr, current->comm, task_pid_nr(current), regs->pc);
261 info.si_signo = SIGBUS;
262 info.si_errno = 0;
263 info.si_code = BUS_ADRALN;
264 info.si_addr = (void *) regs->excvaddr;
265 force_sig_info(SIGSEGV, &info, current);
266
267}
268#endif
269#endif
270
271void
272do_debug(struct pt_regs *regs)
273{
274#ifdef CONFIG_KGDB
275
276
277
278
279
280 if (gdb_enter) {
281 extern void gdb_handle_exception(struct pt_regs *);
282 gdb_handle_exception(regs);
283 return_from_debug_flag = 1;
284 return;
285 }
286#endif
287
288 __die_if_kernel("Breakpoint in kernel", regs, SIGKILL);
289
290
291
292 force_sig(SIGTRAP, current);
293}
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309#define set_handler(idx,handler) (exc_table[idx] = (unsigned long) (handler))
310
311void __init trap_init(void)
312{
313 int i;
314
315
316
317 for(i = 0; i < 64; i++) {
318 set_handler(EXC_TABLE_FAST_USER/4 + i, user_exception);
319 set_handler(EXC_TABLE_FAST_KERNEL/4 + i, kernel_exception);
320 set_handler(EXC_TABLE_DEFAULT/4 + i, do_unhandled);
321 }
322
323
324
325 for(i = 0; dispatch_init_table[i].cause >= 0; i++) {
326
327 int fast = dispatch_init_table[i].fast;
328 int cause = dispatch_init_table[i].cause;
329 void *handler = dispatch_init_table[i].handler;
330
331 if (fast == 0)
332 set_handler (EXC_TABLE_DEFAULT/4 + cause, handler);
333 if (fast && fast & USER)
334 set_handler (EXC_TABLE_FAST_USER/4 + cause, handler);
335 if (fast && fast & KRNL)
336 set_handler (EXC_TABLE_FAST_KERNEL/4 + cause, handler);
337 }
338
339
340
341 i = (unsigned long)exc_table;
342 __asm__ __volatile__("wsr %0, "__stringify(EXCSAVE_1)"\n" : : "a" (i));
343}
344
345
346
347
348
349void show_regs(struct pt_regs * regs)
350{
351 int i, wmask;
352
353 wmask = regs->wmask & ~1;
354
355 for (i = 0; i < 16; i++) {
356 if ((i % 8) == 0)
357 printk(KERN_INFO "a%02d:", i);
358 printk(KERN_CONT " %08lx", regs->areg[i]);
359 }
360 printk(KERN_CONT "\n");
361
362 printk("pc: %08lx, ps: %08lx, depc: %08lx, excvaddr: %08lx\n",
363 regs->pc, regs->ps, regs->depc, regs->excvaddr);
364 printk("lbeg: %08lx, lend: %08lx lcount: %08lx, sar: %08lx\n",
365 regs->lbeg, regs->lend, regs->lcount, regs->sar);
366 if (user_mode(regs))
367 printk("wb: %08lx, ws: %08lx, wmask: %08lx, syscall: %ld\n",
368 regs->windowbase, regs->windowstart, regs->wmask,
369 regs->syscall);
370}
371
372static __always_inline unsigned long *stack_pointer(struct task_struct *task)
373{
374 unsigned long *sp;
375
376 if (!task || task == current)
377 __asm__ __volatile__ ("mov %0, a1\n" : "=a"(sp));
378 else
379 sp = (unsigned long *)task->thread.sp;
380
381 return sp;
382}
383
384void show_trace(struct task_struct *task, unsigned long *sp)
385{
386 unsigned long a0, a1, pc;
387 unsigned long sp_start, sp_end;
388
389 if (sp)
390 a1 = (unsigned long)sp;
391 else
392 a1 = (unsigned long)stack_pointer(task);
393
394 sp_start = a1 & ~(THREAD_SIZE-1);
395 sp_end = sp_start + THREAD_SIZE;
396
397 printk("Call Trace:");
398#ifdef CONFIG_KALLSYMS
399 printk("\n");
400#endif
401 spill_registers();
402
403 while (a1 > sp_start && a1 < sp_end) {
404 sp = (unsigned long*)a1;
405
406 a0 = *(sp - 4);
407 a1 = *(sp - 3);
408
409 if (a1 <= (unsigned long) sp)
410 break;
411
412 pc = MAKE_PC_FROM_RA(a0, a1);
413
414 if (kernel_text_address(pc)) {
415 printk(" [<%08lx>] ", pc);
416 print_symbol("%s\n", pc);
417 }
418 }
419 printk("\n");
420}
421
422
423
424
425
426
427static int kstack_depth_to_print = 24;
428
429void show_stack(struct task_struct *task, unsigned long *sp)
430{
431 int i = 0;
432 unsigned long *stack;
433
434 if (!sp)
435 sp = stack_pointer(task);
436 stack = sp;
437
438 printk("\nStack: ");
439
440 for (i = 0; i < kstack_depth_to_print; i++) {
441 if (kstack_end(sp))
442 break;
443 if (i && ((i % 8) == 0))
444 printk("\n ");
445 printk("%08lx ", *sp++);
446 }
447 printk("\n");
448 show_trace(task, stack);
449}
450
451void dump_stack(void)
452{
453 show_stack(current, NULL);
454}
455
456EXPORT_SYMBOL(dump_stack);
457
458
459void show_code(unsigned int *pc)
460{
461 long i;
462
463 printk("\nCode:");
464
465 for(i = -3 ; i < 6 ; i++) {
466 unsigned long insn;
467 if (__get_user(insn, pc + i)) {
468 printk(" (Bad address in pc)\n");
469 break;
470 }
471 printk("%c%08lx%c",(i?' ':'<'),insn,(i?' ':'>'));
472 }
473}
474
475DEFINE_SPINLOCK(die_lock);
476
477void die(const char * str, struct pt_regs * regs, long err)
478{
479 static int die_counter;
480 int nl = 0;
481
482 console_verbose();
483 spin_lock_irq(&die_lock);
484
485 printk("%s: sig: %ld [#%d]\n", str, err, ++die_counter);
486#ifdef CONFIG_PREEMPT
487 printk("PREEMPT ");
488 nl = 1;
489#endif
490 if (nl)
491 printk("\n");
492 show_regs(regs);
493 if (!user_mode(regs))
494 show_stack(NULL, (unsigned long*)regs->areg[1]);
495
496 add_taint(TAINT_DIE);
497 spin_unlock_irq(&die_lock);
498
499 if (in_interrupt())
500 panic("Fatal exception in interrupt");
501
502 if (panic_on_oops)
503 panic("Fatal exception");
504
505 do_exit(err);
506}
507
508
509