1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1994 - 1999, 2000, 01, 06 Ralf Baechle
7 * Copyright (C) 1995, 1996 Paul M. Antoine
8 * Copyright (C) 1998 Ulf Carlsson
9 * Copyright (C) 1999 Silicon Graphics, Inc.
10 * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
11 * Copyright (C) 2000, 01 MIPS Technologies, Inc.
12 * Copyright (C) 2002, 2003, 2004, 2005, 2007 Maciej W. Rozycki
13 */
14 #include <linux/bug.h>
15 #include <linux/compiler.h>
16 #include <linux/init.h>
17 #include <linux/mm.h>
18 #include <linux/module.h>
19 #include <linux/sched.h>
20 #include <linux/smp.h>
21 #include <linux/spinlock.h>
22 #include <linux/kallsyms.h>
23 #include <linux/bootmem.h>
24 #include <linux/interrupt.h>
25 #include <linux/ptrace.h>
26 #include <linux/kgdb.h>
27 #include <linux/kdebug.h>
28
29 #include <asm/bootinfo.h>
30 #include <asm/branch.h>
31 #include <asm/break.h>
32 #include <asm/cpu.h>
33 #include <asm/dsp.h>
34 #include <asm/fpu.h>
35 #include <asm/fpu_emulator.h>
36 #include <asm/mipsregs.h>
37 #include <asm/mipsmtregs.h>
38 #include <asm/module.h>
39 #include <asm/pgtable.h>
40 #include <asm/ptrace.h>
41 #include <asm/sections.h>
42 #include <asm/system.h>
43 #include <asm/tlbdebug.h>
44 #include <asm/traps.h>
45 #include <asm/uaccess.h>
46 #include <asm/watch.h>
47 #include <asm/mmu_context.h>
48 #include <asm/types.h>
49 #include <asm/stacktrace.h>
50 #include <asm/irq.h>
51
52 extern void check_wait(void);
53 extern asmlinkage void r4k_wait(void);
54 extern asmlinkage void rollback_handle_int(void);
55 extern asmlinkage void handle_int(void);
56 extern asmlinkage void handle_tlbm(void);
57 extern asmlinkage void handle_tlbl(void);
58 extern asmlinkage void handle_tlbs(void);
59 extern asmlinkage void handle_adel(void);
60 extern asmlinkage void handle_ades(void);
61 extern asmlinkage void handle_ibe(void);
62 extern asmlinkage void handle_dbe(void);
63 extern asmlinkage void handle_sys(void);
64 extern asmlinkage void handle_bp(void);
65 extern asmlinkage void handle_ri(void);
66 extern asmlinkage void handle_ri_rdhwr_vivt(void);
67 extern asmlinkage void handle_ri_rdhwr(void);
68 extern asmlinkage void handle_cpu(void);
69 extern asmlinkage void handle_ov(void);
70 extern asmlinkage void handle_tr(void);
71 extern asmlinkage void handle_fpe(void);
72 extern asmlinkage void handle_mdmx(void);
73 extern asmlinkage void handle_watch(void);
74 extern asmlinkage void handle_mt(void);
75 extern asmlinkage void handle_dsp(void);
76 extern asmlinkage void handle_mcheck(void);
77 extern asmlinkage void handle_reserved(void);
78
79 extern int fpu_emulator_cop1Handler(struct pt_regs *xcp,
80 struct mips_fpu_struct *ctx, int has_fpu);
81
82 #ifdef CONFIG_CPU_CAVIUM_OCTEON
83 extern asmlinkage void octeon_cop2_restore(struct octeon_cop2_state *task);
84 #endif
85
86 void (*board_be_init)(void);
87 int (*board_be_handler)(struct pt_regs *regs, int is_fixup);
88 void (*board_nmi_handler_setup)(void);
89 void (*board_ejtag_handler_setup)(void);
90 void (*board_bind_eic_interrupt)(int irq, int regset);
91
92
show_raw_backtrace(unsigned long reg29)93 static void show_raw_backtrace(unsigned long reg29)
94 {
95 unsigned long *sp = (unsigned long *)(reg29 & ~3);
96 unsigned long addr;
97
98 printk("Call Trace:");
99 #ifdef CONFIG_KALLSYMS
100 printk("\n");
101 #endif
102 while (!kstack_end(sp)) {
103 unsigned long __user *p =
104 (unsigned long __user *)(unsigned long)sp++;
105 if (__get_user(addr, p)) {
106 printk(" (Bad stack address)");
107 break;
108 }
109 if (__kernel_text_address(addr))
110 print_ip_sym(addr);
111 }
112 printk("\n");
113 }
114
115 #ifdef CONFIG_KALLSYMS
116 int raw_show_trace;
set_raw_show_trace(char * str)117 static int __init set_raw_show_trace(char *str)
118 {
119 raw_show_trace = 1;
120 return 1;
121 }
122 __setup("raw_show_trace", set_raw_show_trace);
123 #endif
124
show_backtrace(struct task_struct * task,const struct pt_regs * regs)125 static void show_backtrace(struct task_struct *task, const struct pt_regs *regs)
126 {
127 unsigned long sp = regs->regs[29];
128 unsigned long ra = regs->regs[31];
129 unsigned long pc = regs->cp0_epc;
130
131 if (raw_show_trace || !__kernel_text_address(pc)) {
132 show_raw_backtrace(sp);
133 return;
134 }
135 printk("Call Trace:\n");
136 do {
137 print_ip_sym(pc);
138 pc = unwind_stack(task, &sp, pc, &ra);
139 } while (pc);
140 printk("\n");
141 }
142
143 /*
144 * This routine abuses get_user()/put_user() to reference pointers
145 * with at least a bit of error checking ...
146 */
show_stacktrace(struct task_struct * task,const struct pt_regs * regs)147 static void show_stacktrace(struct task_struct *task,
148 const struct pt_regs *regs)
149 {
150 const int field = 2 * sizeof(unsigned long);
151 long stackdata;
152 int i;
153 unsigned long __user *sp = (unsigned long __user *)regs->regs[29];
154
155 printk("Stack :");
156 i = 0;
157 while ((unsigned long) sp & (PAGE_SIZE - 1)) {
158 if (i && ((i % (64 / field)) == 0))
159 printk("\n ");
160 if (i > 39) {
161 printk(" ...");
162 break;
163 }
164
165 if (__get_user(stackdata, sp++)) {
166 printk(" (Bad stack address)");
167 break;
168 }
169
170 printk(" %0*lx", field, stackdata);
171 i++;
172 }
173 printk("\n");
174 show_backtrace(task, regs);
175 }
176
show_stack(struct task_struct * task,unsigned long * sp)177 void show_stack(struct task_struct *task, unsigned long *sp)
178 {
179 struct pt_regs regs;
180 if (sp) {
181 regs.regs[29] = (unsigned long)sp;
182 regs.regs[31] = 0;
183 regs.cp0_epc = 0;
184 } else {
185 if (task && task != current) {
186 regs.regs[29] = task->thread.reg29;
187 regs.regs[31] = 0;
188 regs.cp0_epc = task->thread.reg31;
189 } else {
190 prepare_frametrace(®s);
191 }
192 }
193 show_stacktrace(task, ®s);
194 }
195
196 /*
197 * The architecture-independent dump_stack generator
198 */
dump_stack(void)199 void dump_stack(void)
200 {
201 struct pt_regs regs;
202
203 prepare_frametrace(®s);
204 show_backtrace(current, ®s);
205 }
206
207 EXPORT_SYMBOL(dump_stack);
208
show_code(unsigned int __user * pc)209 static void show_code(unsigned int __user *pc)
210 {
211 long i;
212 unsigned short __user *pc16 = NULL;
213
214 printk("\nCode:");
215
216 if ((unsigned long)pc & 1)
217 pc16 = (unsigned short __user *)((unsigned long)pc & ~1);
218 for(i = -3 ; i < 6 ; i++) {
219 unsigned int insn;
220 if (pc16 ? __get_user(insn, pc16 + i) : __get_user(insn, pc + i)) {
221 printk(" (Bad address in epc)\n");
222 break;
223 }
224 printk("%c%0*x%c", (i?' ':'<'), pc16 ? 4 : 8, insn, (i?' ':'>'));
225 }
226 }
227
__show_regs(const struct pt_regs * regs)228 static void __show_regs(const struct pt_regs *regs)
229 {
230 const int field = 2 * sizeof(unsigned long);
231 unsigned int cause = regs->cp0_cause;
232 int i;
233
234 printk("Cpu %d\n", smp_processor_id());
235
236 /*
237 * Saved main processor registers
238 */
239 for (i = 0; i < 32; ) {
240 if ((i % 4) == 0)
241 printk("$%2d :", i);
242 if (i == 0)
243 printk(" %0*lx", field, 0UL);
244 else if (i == 26 || i == 27)
245 printk(" %*s", field, "");
246 else
247 printk(" %0*lx", field, regs->regs[i]);
248
249 i++;
250 if ((i % 4) == 0)
251 printk("\n");
252 }
253
254 #ifdef CONFIG_CPU_HAS_SMARTMIPS
255 printk("Acx : %0*lx\n", field, regs->acx);
256 #endif
257 printk("Hi : %0*lx\n", field, regs->hi);
258 printk("Lo : %0*lx\n", field, regs->lo);
259
260 /*
261 * Saved cp0 registers
262 */
263 printk("epc : %0*lx %pS\n", field, regs->cp0_epc,
264 (void *) regs->cp0_epc);
265 printk(" %s\n", print_tainted());
266 printk("ra : %0*lx %pS\n", field, regs->regs[31],
267 (void *) regs->regs[31]);
268
269 printk("Status: %08x ", (uint32_t) regs->cp0_status);
270
271 if (current_cpu_data.isa_level == MIPS_CPU_ISA_I) {
272 if (regs->cp0_status & ST0_KUO)
273 printk("KUo ");
274 if (regs->cp0_status & ST0_IEO)
275 printk("IEo ");
276 if (regs->cp0_status & ST0_KUP)
277 printk("KUp ");
278 if (regs->cp0_status & ST0_IEP)
279 printk("IEp ");
280 if (regs->cp0_status & ST0_KUC)
281 printk("KUc ");
282 if (regs->cp0_status & ST0_IEC)
283 printk("IEc ");
284 } else {
285 if (regs->cp0_status & ST0_KX)
286 printk("KX ");
287 if (regs->cp0_status & ST0_SX)
288 printk("SX ");
289 if (regs->cp0_status & ST0_UX)
290 printk("UX ");
291 switch (regs->cp0_status & ST0_KSU) {
292 case KSU_USER:
293 printk("USER ");
294 break;
295 case KSU_SUPERVISOR:
296 printk("SUPERVISOR ");
297 break;
298 case KSU_KERNEL:
299 printk("KERNEL ");
300 break;
301 default:
302 printk("BAD_MODE ");
303 break;
304 }
305 if (regs->cp0_status & ST0_ERL)
306 printk("ERL ");
307 if (regs->cp0_status & ST0_EXL)
308 printk("EXL ");
309 if (regs->cp0_status & ST0_IE)
310 printk("IE ");
311 }
312 printk("\n");
313
314 printk("Cause : %08x\n", cause);
315
316 cause = (cause & CAUSEF_EXCCODE) >> CAUSEB_EXCCODE;
317 if (1 <= cause && cause <= 5)
318 printk("BadVA : %0*lx\n", field, regs->cp0_badvaddr);
319
320 printk("PrId : %08x (%s)\n", read_c0_prid(),
321 cpu_name_string());
322 }
323
324 /*
325 * FIXME: really the generic show_regs should take a const pointer argument.
326 */
show_regs(struct pt_regs * regs)327 void show_regs(struct pt_regs *regs)
328 {
329 __show_regs((struct pt_regs *)regs);
330 }
331
show_registers(const struct pt_regs * regs)332 void show_registers(const struct pt_regs *regs)
333 {
334 const int field = 2 * sizeof(unsigned long);
335
336 __show_regs(regs);
337 print_modules();
338 printk("Process %s (pid: %d, threadinfo=%p, task=%p, tls=%0*lx)\n",
339 current->comm, current->pid, current_thread_info(), current,
340 field, current_thread_info()->tp_value);
341 if (cpu_has_userlocal) {
342 unsigned long tls;
343
344 tls = read_c0_userlocal();
345 if (tls != current_thread_info()->tp_value)
346 printk("*HwTLS: %0*lx\n", field, tls);
347 }
348
349 show_stacktrace(current, regs);
350 show_code((unsigned int __user *) regs->cp0_epc);
351 printk("\n");
352 }
353
354 static DEFINE_SPINLOCK(die_lock);
355
die(const char * str,const struct pt_regs * regs)356 void __noreturn die(const char * str, const struct pt_regs * regs)
357 {
358 static int die_counter;
359 #ifdef CONFIG_MIPS_MT_SMTC
360 unsigned long dvpret = dvpe();
361 #endif /* CONFIG_MIPS_MT_SMTC */
362
363 console_verbose();
364 spin_lock_irq(&die_lock);
365 bust_spinlocks(1);
366 #ifdef CONFIG_MIPS_MT_SMTC
367 mips_mt_regdump(dvpret);
368 #endif /* CONFIG_MIPS_MT_SMTC */
369 printk("%s[#%d]:\n", str, ++die_counter);
370 show_registers(regs);
371 add_taint(TAINT_DIE);
372 spin_unlock_irq(&die_lock);
373
374 if (in_interrupt())
375 panic("Fatal exception in interrupt");
376
377 if (panic_on_oops) {
378 printk(KERN_EMERG "Fatal exception: panic in 5 seconds\n");
379 ssleep(5);
380 panic("Fatal exception");
381 }
382
383 do_exit(SIGSEGV);
384 }
385
386 extern struct exception_table_entry __start___dbe_table[];
387 extern struct exception_table_entry __stop___dbe_table[];
388
389 __asm__(
390 " .section __dbe_table, \"a\"\n"
391 " .previous \n");
392
393 /* Given an address, look for it in the exception tables. */
search_dbe_tables(unsigned long addr)394 static const struct exception_table_entry *search_dbe_tables(unsigned long addr)
395 {
396 const struct exception_table_entry *e;
397
398 e = search_extable(__start___dbe_table, __stop___dbe_table - 1, addr);
399 if (!e)
400 e = search_module_dbetables(addr);
401 return e;
402 }
403
do_be(struct pt_regs * regs)404 asmlinkage void do_be(struct pt_regs *regs)
405 {
406 const int field = 2 * sizeof(unsigned long);
407 const struct exception_table_entry *fixup = NULL;
408 int data = regs->cp0_cause & 4;
409 int action = MIPS_BE_FATAL;
410
411 /* XXX For now. Fixme, this searches the wrong table ... */
412 if (data && !user_mode(regs))
413 fixup = search_dbe_tables(exception_epc(regs));
414
415 if (fixup)
416 action = MIPS_BE_FIXUP;
417
418 if (board_be_handler)
419 action = board_be_handler(regs, fixup != NULL);
420
421 switch (action) {
422 case MIPS_BE_DISCARD:
423 return;
424 case MIPS_BE_FIXUP:
425 if (fixup) {
426 regs->cp0_epc = fixup->nextinsn;
427 return;
428 }
429 break;
430 default:
431 break;
432 }
433
434 /*
435 * Assume it would be too dangerous to continue ...
436 */
437 printk(KERN_ALERT "%s bus error, epc == %0*lx, ra == %0*lx\n",
438 data ? "Data" : "Instruction",
439 field, regs->cp0_epc, field, regs->regs[31]);
440 if (notify_die(DIE_OOPS, "bus error", regs, SIGBUS, 0, 0)
441 == NOTIFY_STOP)
442 return;
443
444 die_if_kernel("Oops", regs);
445 force_sig(SIGBUS, current);
446 }
447
448 /*
449 * ll/sc, rdhwr, sync emulation
450 */
451
452 #define OPCODE 0xfc000000
453 #define BASE 0x03e00000
454 #define RT 0x001f0000
455 #define OFFSET 0x0000ffff
456 #define LL 0xc0000000
457 #define SC 0xe0000000
458 #define SPEC0 0x00000000
459 #define SPEC3 0x7c000000
460 #define RD 0x0000f800
461 #define FUNC 0x0000003f
462 #define SYNC 0x0000000f
463 #define RDHWR 0x0000003b
464
465 /*
466 * The ll_bit is cleared by r*_switch.S
467 */
468
469 unsigned long ll_bit;
470
471 static struct task_struct *ll_task = NULL;
472
simulate_ll(struct pt_regs * regs,unsigned int opcode)473 static inline int simulate_ll(struct pt_regs *regs, unsigned int opcode)
474 {
475 unsigned long value, __user *vaddr;
476 long offset;
477
478 /*
479 * analyse the ll instruction that just caused a ri exception
480 * and put the referenced address to addr.
481 */
482
483 /* sign extend offset */
484 offset = opcode & OFFSET;
485 offset <<= 16;
486 offset >>= 16;
487
488 vaddr = (unsigned long __user *)
489 ((unsigned long)(regs->regs[(opcode & BASE) >> 21]) + offset);
490
491 if ((unsigned long)vaddr & 3)
492 return SIGBUS;
493 if (get_user(value, vaddr))
494 return SIGSEGV;
495
496 preempt_disable();
497
498 if (ll_task == NULL || ll_task == current) {
499 ll_bit = 1;
500 } else {
501 ll_bit = 0;
502 }
503 ll_task = current;
504
505 preempt_enable();
506
507 regs->regs[(opcode & RT) >> 16] = value;
508
509 return 0;
510 }
511
simulate_sc(struct pt_regs * regs,unsigned int opcode)512 static inline int simulate_sc(struct pt_regs *regs, unsigned int opcode)
513 {
514 unsigned long __user *vaddr;
515 unsigned long reg;
516 long offset;
517
518 /*
519 * analyse the sc instruction that just caused a ri exception
520 * and put the referenced address to addr.
521 */
522
523 /* sign extend offset */
524 offset = opcode & OFFSET;
525 offset <<= 16;
526 offset >>= 16;
527
528 vaddr = (unsigned long __user *)
529 ((unsigned long)(regs->regs[(opcode & BASE) >> 21]) + offset);
530 reg = (opcode & RT) >> 16;
531
532 if ((unsigned long)vaddr & 3)
533 return SIGBUS;
534
535 preempt_disable();
536
537 if (ll_bit == 0 || ll_task != current) {
538 regs->regs[reg] = 0;
539 preempt_enable();
540 return 0;
541 }
542
543 preempt_enable();
544
545 if (put_user(regs->regs[reg], vaddr))
546 return SIGSEGV;
547
548 regs->regs[reg] = 1;
549
550 return 0;
551 }
552
553 /*
554 * ll uses the opcode of lwc0 and sc uses the opcode of swc0. That is both
555 * opcodes are supposed to result in coprocessor unusable exceptions if
556 * executed on ll/sc-less processors. That's the theory. In practice a
557 * few processors such as NEC's VR4100 throw reserved instruction exceptions
558 * instead, so we're doing the emulation thing in both exception handlers.
559 */
simulate_llsc(struct pt_regs * regs,unsigned int opcode)560 static int simulate_llsc(struct pt_regs *regs, unsigned int opcode)
561 {
562 if ((opcode & OPCODE) == LL)
563 return simulate_ll(regs, opcode);
564 if ((opcode & OPCODE) == SC)
565 return simulate_sc(regs, opcode);
566
567 return -1; /* Must be something else ... */
568 }
569
570 /*
571 * Simulate trapping 'rdhwr' instructions to provide user accessible
572 * registers not implemented in hardware.
573 */
simulate_rdhwr(struct pt_regs * regs,unsigned int opcode)574 static int simulate_rdhwr(struct pt_regs *regs, unsigned int opcode)
575 {
576 struct thread_info *ti = task_thread_info(current);
577
578 if ((opcode & OPCODE) == SPEC3 && (opcode & FUNC) == RDHWR) {
579 int rd = (opcode & RD) >> 11;
580 int rt = (opcode & RT) >> 16;
581 switch (rd) {
582 case 0: /* CPU number */
583 regs->regs[rt] = smp_processor_id();
584 return 0;
585 case 1: /* SYNCI length */
586 regs->regs[rt] = min(current_cpu_data.dcache.linesz,
587 current_cpu_data.icache.linesz);
588 return 0;
589 case 2: /* Read count register */
590 regs->regs[rt] = read_c0_count();
591 return 0;
592 case 3: /* Count register resolution */
593 switch (current_cpu_data.cputype) {
594 case CPU_20KC:
595 case CPU_25KF:
596 regs->regs[rt] = 1;
597 break;
598 default:
599 regs->regs[rt] = 2;
600 }
601 return 0;
602 case 29:
603 regs->regs[rt] = ti->tp_value;
604 return 0;
605 default:
606 return -1;
607 }
608 }
609
610 /* Not ours. */
611 return -1;
612 }
613
simulate_sync(struct pt_regs * regs,unsigned int opcode)614 static int simulate_sync(struct pt_regs *regs, unsigned int opcode)
615 {
616 if ((opcode & OPCODE) == SPEC0 && (opcode & FUNC) == SYNC)
617 return 0;
618
619 return -1; /* Must be something else ... */
620 }
621
do_ov(struct pt_regs * regs)622 asmlinkage void do_ov(struct pt_regs *regs)
623 {
624 siginfo_t info;
625
626 die_if_kernel("Integer overflow", regs);
627
628 info.si_code = FPE_INTOVF;
629 info.si_signo = SIGFPE;
630 info.si_errno = 0;
631 info.si_addr = (void __user *) regs->cp0_epc;
632 force_sig_info(SIGFPE, &info, current);
633 }
634
635 /*
636 * XXX Delayed fp exceptions when doing a lazy ctx switch XXX
637 */
do_fpe(struct pt_regs * regs,unsigned long fcr31)638 asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31)
639 {
640 siginfo_t info;
641
642 if (notify_die(DIE_FP, "FP exception", regs, SIGFPE, 0, 0)
643 == NOTIFY_STOP)
644 return;
645 die_if_kernel("FP exception in kernel code", regs);
646
647 if (fcr31 & FPU_CSR_UNI_X) {
648 int sig;
649
650 /*
651 * Unimplemented operation exception. If we've got the full
652 * software emulator on-board, let's use it...
653 *
654 * Force FPU to dump state into task/thread context. We're
655 * moving a lot of data here for what is probably a single
656 * instruction, but the alternative is to pre-decode the FP
657 * register operands before invoking the emulator, which seems
658 * a bit extreme for what should be an infrequent event.
659 */
660 /* Ensure 'resume' not overwrite saved fp context again. */
661 lose_fpu(1);
662
663 /* Run the emulator */
664 sig = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1);
665
666 /*
667 * We can't allow the emulated instruction to leave any of
668 * the cause bit set in $fcr31.
669 */
670 current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X;
671
672 /* Restore the hardware register state */
673 own_fpu(1); /* Using the FPU again. */
674
675 /* If something went wrong, signal */
676 if (sig)
677 force_sig(sig, current);
678
679 return;
680 } else if (fcr31 & FPU_CSR_INV_X)
681 info.si_code = FPE_FLTINV;
682 else if (fcr31 & FPU_CSR_DIV_X)
683 info.si_code = FPE_FLTDIV;
684 else if (fcr31 & FPU_CSR_OVF_X)
685 info.si_code = FPE_FLTOVF;
686 else if (fcr31 & FPU_CSR_UDF_X)
687 info.si_code = FPE_FLTUND;
688 else if (fcr31 & FPU_CSR_INE_X)
689 info.si_code = FPE_FLTRES;
690 else
691 info.si_code = __SI_FAULT;
692 info.si_signo = SIGFPE;
693 info.si_errno = 0;
694 info.si_addr = (void __user *) regs->cp0_epc;
695 force_sig_info(SIGFPE, &info, current);
696 }
697
do_trap_or_bp(struct pt_regs * regs,unsigned int code,const char * str)698 static void do_trap_or_bp(struct pt_regs *regs, unsigned int code,
699 const char *str)
700 {
701 siginfo_t info;
702 char b[40];
703
704 if (notify_die(DIE_TRAP, str, regs, code, 0, 0) == NOTIFY_STOP)
705 return;
706
707 /*
708 * A short test says that IRIX 5.3 sends SIGTRAP for all trap
709 * insns, even for trap and break codes that indicate arithmetic
710 * failures. Weird ...
711 * But should we continue the brokenness??? --macro
712 */
713 switch (code) {
714 case BRK_OVERFLOW:
715 case BRK_DIVZERO:
716 scnprintf(b, sizeof(b), "%s instruction in kernel code", str);
717 die_if_kernel(b, regs);
718 if (code == BRK_DIVZERO)
719 info.si_code = FPE_INTDIV;
720 else
721 info.si_code = FPE_INTOVF;
722 info.si_signo = SIGFPE;
723 info.si_errno = 0;
724 info.si_addr = (void __user *) regs->cp0_epc;
725 force_sig_info(SIGFPE, &info, current);
726 break;
727 case BRK_BUG:
728 die_if_kernel("Kernel bug detected", regs);
729 force_sig(SIGTRAP, current);
730 break;
731 case BRK_MEMU:
732 /*
733 * Address errors may be deliberately induced by the FPU
734 * emulator to retake control of the CPU after executing the
735 * instruction in the delay slot of an emulated branch.
736 *
737 * Terminate if exception was recognized as a delay slot return
738 * otherwise handle as normal.
739 */
740 if (do_dsemulret(regs))
741 return;
742
743 die_if_kernel("Math emu break/trap", regs);
744 force_sig(SIGTRAP, current);
745 break;
746 default:
747 scnprintf(b, sizeof(b), "%s instruction in kernel code", str);
748 die_if_kernel(b, regs);
749 force_sig(SIGTRAP, current);
750 }
751 }
752
do_bp(struct pt_regs * regs)753 asmlinkage void do_bp(struct pt_regs *regs)
754 {
755 unsigned int opcode, bcode;
756
757 if (__get_user(opcode, (unsigned int __user *) exception_epc(regs)))
758 goto out_sigsegv;
759
760 /*
761 * There is the ancient bug in the MIPS assemblers that the break
762 * code starts left to bit 16 instead to bit 6 in the opcode.
763 * Gas is bug-compatible, but not always, grrr...
764 * We handle both cases with a simple heuristics. --macro
765 */
766 bcode = ((opcode >> 6) & ((1 << 20) - 1));
767 if (bcode >= (1 << 10))
768 bcode >>= 10;
769
770 do_trap_or_bp(regs, bcode, "Break");
771 return;
772
773 out_sigsegv:
774 force_sig(SIGSEGV, current);
775 }
776
do_tr(struct pt_regs * regs)777 asmlinkage void do_tr(struct pt_regs *regs)
778 {
779 unsigned int opcode, tcode = 0;
780
781 if (__get_user(opcode, (unsigned int __user *) exception_epc(regs)))
782 goto out_sigsegv;
783
784 /* Immediate versions don't provide a code. */
785 if (!(opcode & OPCODE))
786 tcode = ((opcode >> 6) & ((1 << 10) - 1));
787
788 do_trap_or_bp(regs, tcode, "Trap");
789 return;
790
791 out_sigsegv:
792 force_sig(SIGSEGV, current);
793 }
794
do_ri(struct pt_regs * regs)795 asmlinkage void do_ri(struct pt_regs *regs)
796 {
797 unsigned int __user *epc = (unsigned int __user *)exception_epc(regs);
798 unsigned long old_epc = regs->cp0_epc;
799 unsigned int opcode = 0;
800 int status = -1;
801
802 if (notify_die(DIE_RI, "RI Fault", regs, SIGSEGV, 0, 0)
803 == NOTIFY_STOP)
804 return;
805
806 die_if_kernel("Reserved instruction in kernel code", regs);
807
808 if (unlikely(compute_return_epc(regs) < 0))
809 return;
810
811 if (unlikely(get_user(opcode, epc) < 0))
812 status = SIGSEGV;
813
814 if (!cpu_has_llsc && status < 0)
815 status = simulate_llsc(regs, opcode);
816
817 if (status < 0)
818 status = simulate_rdhwr(regs, opcode);
819
820 if (status < 0)
821 status = simulate_sync(regs, opcode);
822
823 if (status < 0)
824 status = SIGILL;
825
826 if (unlikely(status > 0)) {
827 regs->cp0_epc = old_epc; /* Undo skip-over. */
828 force_sig(status, current);
829 }
830 }
831
832 /*
833 * MIPS MT processors may have fewer FPU contexts than CPU threads. If we've
834 * emulated more than some threshold number of instructions, force migration to
835 * a "CPU" that has FP support.
836 */
mt_ase_fp_affinity(void)837 static void mt_ase_fp_affinity(void)
838 {
839 #ifdef CONFIG_MIPS_MT_FPAFF
840 if (mt_fpemul_threshold > 0 &&
841 ((current->thread.emulated_fp++ > mt_fpemul_threshold))) {
842 /*
843 * If there's no FPU present, or if the application has already
844 * restricted the allowed set to exclude any CPUs with FPUs,
845 * we'll skip the procedure.
846 */
847 if (cpus_intersects(current->cpus_allowed, mt_fpu_cpumask)) {
848 cpumask_t tmask;
849
850 current->thread.user_cpus_allowed
851 = current->cpus_allowed;
852 cpus_and(tmask, current->cpus_allowed,
853 mt_fpu_cpumask);
854 set_cpus_allowed(current, tmask);
855 set_thread_flag(TIF_FPUBOUND);
856 }
857 }
858 #endif /* CONFIG_MIPS_MT_FPAFF */
859 }
860
do_cpu(struct pt_regs * regs)861 asmlinkage void do_cpu(struct pt_regs *regs)
862 {
863 unsigned int __user *epc;
864 unsigned long old_epc;
865 unsigned int opcode;
866 unsigned int cpid;
867 int status;
868 unsigned long __maybe_unused flags;
869
870 die_if_kernel("do_cpu invoked from kernel context!", regs);
871
872 cpid = (regs->cp0_cause >> CAUSEB_CE) & 3;
873
874 switch (cpid) {
875 case 0:
876 epc = (unsigned int __user *)exception_epc(regs);
877 old_epc = regs->cp0_epc;
878 opcode = 0;
879 status = -1;
880
881 if (unlikely(compute_return_epc(regs) < 0))
882 return;
883
884 if (unlikely(get_user(opcode, epc) < 0))
885 status = SIGSEGV;
886
887 if (!cpu_has_llsc && status < 0)
888 status = simulate_llsc(regs, opcode);
889
890 if (status < 0)
891 status = simulate_rdhwr(regs, opcode);
892
893 if (status < 0)
894 status = SIGILL;
895
896 if (unlikely(status > 0)) {
897 regs->cp0_epc = old_epc; /* Undo skip-over. */
898 force_sig(status, current);
899 }
900
901 return;
902
903 case 1:
904 if (used_math()) /* Using the FPU again. */
905 own_fpu(1);
906 else { /* First time FPU user. */
907 init_fpu();
908 set_used_math();
909 }
910
911 if (!raw_cpu_has_fpu) {
912 int sig;
913 sig = fpu_emulator_cop1Handler(regs,
914 ¤t->thread.fpu, 0);
915 if (sig)
916 force_sig(sig, current);
917 else
918 mt_ase_fp_affinity();
919 }
920
921 return;
922
923 case 2:
924 #ifdef CONFIG_CPU_CAVIUM_OCTEON
925 prefetch(¤t->thread.cp2);
926 local_irq_save(flags);
927 KSTK_STATUS(current) |= ST0_CU2;
928 status = read_c0_status();
929 write_c0_status(status | ST0_CU2);
930 octeon_cop2_restore(&(current->thread.cp2));
931 write_c0_status(status & ~ST0_CU2);
932 local_irq_restore(flags);
933 return;
934 #endif
935 case 3:
936 break;
937 }
938
939 force_sig(SIGILL, current);
940 }
941
do_mdmx(struct pt_regs * regs)942 asmlinkage void do_mdmx(struct pt_regs *regs)
943 {
944 force_sig(SIGILL, current);
945 }
946
947 /*
948 * Called with interrupts disabled.
949 */
do_watch(struct pt_regs * regs)950 asmlinkage void do_watch(struct pt_regs *regs)
951 {
952 u32 cause;
953
954 /*
955 * Clear WP (bit 22) bit of cause register so we don't loop
956 * forever.
957 */
958 cause = read_c0_cause();
959 cause &= ~(1 << 22);
960 write_c0_cause(cause);
961
962 /*
963 * If the current thread has the watch registers loaded, save
964 * their values and send SIGTRAP. Otherwise another thread
965 * left the registers set, clear them and continue.
966 */
967 if (test_tsk_thread_flag(current, TIF_LOAD_WATCH)) {
968 mips_read_watch_registers();
969 local_irq_enable();
970 force_sig(SIGTRAP, current);
971 } else {
972 mips_clear_watch_registers();
973 local_irq_enable();
974 }
975 }
976
do_mcheck(struct pt_regs * regs)977 asmlinkage void do_mcheck(struct pt_regs *regs)
978 {
979 const int field = 2 * sizeof(unsigned long);
980 int multi_match = regs->cp0_status & ST0_TS;
981
982 show_regs(regs);
983
984 if (multi_match) {
985 printk("Index : %0x\n", read_c0_index());
986 printk("Pagemask: %0x\n", read_c0_pagemask());
987 printk("EntryHi : %0*lx\n", field, read_c0_entryhi());
988 printk("EntryLo0: %0*lx\n", field, read_c0_entrylo0());
989 printk("EntryLo1: %0*lx\n", field, read_c0_entrylo1());
990 printk("\n");
991 dump_tlb_all();
992 }
993
994 show_code((unsigned int __user *) regs->cp0_epc);
995
996 /*
997 * Some chips may have other causes of machine check (e.g. SB1
998 * graduation timer)
999 */
1000 panic("Caught Machine Check exception - %scaused by multiple "
1001 "matching entries in the TLB.",
1002 (multi_match) ? "" : "not ");
1003 }
1004
do_mt(struct pt_regs * regs)1005 asmlinkage void do_mt(struct pt_regs *regs)
1006 {
1007 int subcode;
1008
1009 subcode = (read_vpe_c0_vpecontrol() & VPECONTROL_EXCPT)
1010 >> VPECONTROL_EXCPT_SHIFT;
1011 switch (subcode) {
1012 case 0:
1013 printk(KERN_DEBUG "Thread Underflow\n");
1014 break;
1015 case 1:
1016 printk(KERN_DEBUG "Thread Overflow\n");
1017 break;
1018 case 2:
1019 printk(KERN_DEBUG "Invalid YIELD Qualifier\n");
1020 break;
1021 case 3:
1022 printk(KERN_DEBUG "Gating Storage Exception\n");
1023 break;
1024 case 4:
1025 printk(KERN_DEBUG "YIELD Scheduler Exception\n");
1026 break;
1027 case 5:
1028 printk(KERN_DEBUG "Gating Storage Schedulier Exception\n");
1029 break;
1030 default:
1031 printk(KERN_DEBUG "*** UNKNOWN THREAD EXCEPTION %d ***\n",
1032 subcode);
1033 break;
1034 }
1035 die_if_kernel("MIPS MT Thread exception in kernel", regs);
1036
1037 force_sig(SIGILL, current);
1038 }
1039
1040
do_dsp(struct pt_regs * regs)1041 asmlinkage void do_dsp(struct pt_regs *regs)
1042 {
1043 if (cpu_has_dsp)
1044 panic("Unexpected DSP exception\n");
1045
1046 force_sig(SIGILL, current);
1047 }
1048
do_reserved(struct pt_regs * regs)1049 asmlinkage void do_reserved(struct pt_regs *regs)
1050 {
1051 /*
1052 * Game over - no way to handle this if it ever occurs. Most probably
1053 * caused by a new unknown cpu type or after another deadly
1054 * hard/software error.
1055 */
1056 show_regs(regs);
1057 panic("Caught reserved exception %ld - should not happen.",
1058 (regs->cp0_cause & 0x7f) >> 2);
1059 }
1060
1061 static int __initdata l1parity = 1;
nol1parity(char * s)1062 static int __init nol1parity(char *s)
1063 {
1064 l1parity = 0;
1065 return 1;
1066 }
1067 __setup("nol1par", nol1parity);
1068 static int __initdata l2parity = 1;
nol2parity(char * s)1069 static int __init nol2parity(char *s)
1070 {
1071 l2parity = 0;
1072 return 1;
1073 }
1074 __setup("nol2par", nol2parity);
1075
1076 /*
1077 * Some MIPS CPUs can enable/disable for cache parity detection, but do
1078 * it different ways.
1079 */
parity_protection_init(void)1080 static inline void parity_protection_init(void)
1081 {
1082 switch (current_cpu_type()) {
1083 case CPU_24K:
1084 case CPU_34K:
1085 case CPU_74K:
1086 case CPU_1004K:
1087 {
1088 #define ERRCTL_PE 0x80000000
1089 #define ERRCTL_L2P 0x00800000
1090 unsigned long errctl;
1091 unsigned int l1parity_present, l2parity_present;
1092
1093 errctl = read_c0_ecc();
1094 errctl &= ~(ERRCTL_PE|ERRCTL_L2P);
1095
1096 /* probe L1 parity support */
1097 write_c0_ecc(errctl | ERRCTL_PE);
1098 back_to_back_c0_hazard();
1099 l1parity_present = (read_c0_ecc() & ERRCTL_PE);
1100
1101 /* probe L2 parity support */
1102 write_c0_ecc(errctl|ERRCTL_L2P);
1103 back_to_back_c0_hazard();
1104 l2parity_present = (read_c0_ecc() & ERRCTL_L2P);
1105
1106 if (l1parity_present && l2parity_present) {
1107 if (l1parity)
1108 errctl |= ERRCTL_PE;
1109 if (l1parity ^ l2parity)
1110 errctl |= ERRCTL_L2P;
1111 } else if (l1parity_present) {
1112 if (l1parity)
1113 errctl |= ERRCTL_PE;
1114 } else if (l2parity_present) {
1115 if (l2parity)
1116 errctl |= ERRCTL_L2P;
1117 } else {
1118 /* No parity available */
1119 }
1120
1121 printk(KERN_INFO "Writing ErrCtl register=%08lx\n", errctl);
1122
1123 write_c0_ecc(errctl);
1124 back_to_back_c0_hazard();
1125 errctl = read_c0_ecc();
1126 printk(KERN_INFO "Readback ErrCtl register=%08lx\n", errctl);
1127
1128 if (l1parity_present)
1129 printk(KERN_INFO "Cache parity protection %sabled\n",
1130 (errctl & ERRCTL_PE) ? "en" : "dis");
1131
1132 if (l2parity_present) {
1133 if (l1parity_present && l1parity)
1134 errctl ^= ERRCTL_L2P;
1135 printk(KERN_INFO "L2 cache parity protection %sabled\n",
1136 (errctl & ERRCTL_L2P) ? "en" : "dis");
1137 }
1138 }
1139 break;
1140
1141 case CPU_5KC:
1142 write_c0_ecc(0x80000000);
1143 back_to_back_c0_hazard();
1144 /* Set the PE bit (bit 31) in the c0_errctl register. */
1145 printk(KERN_INFO "Cache parity protection %sabled\n",
1146 (read_c0_ecc() & 0x80000000) ? "en" : "dis");
1147 break;
1148 case CPU_20KC:
1149 case CPU_25KF:
1150 /* Clear the DE bit (bit 16) in the c0_status register. */
1151 printk(KERN_INFO "Enable cache parity protection for "
1152 "MIPS 20KC/25KF CPUs.\n");
1153 clear_c0_status(ST0_DE);
1154 break;
1155 default:
1156 break;
1157 }
1158 }
1159
cache_parity_error(void)1160 asmlinkage void cache_parity_error(void)
1161 {
1162 const int field = 2 * sizeof(unsigned long);
1163 unsigned int reg_val;
1164
1165 /* For the moment, report the problem and hang. */
1166 printk("Cache error exception:\n");
1167 printk("cp0_errorepc == %0*lx\n", field, read_c0_errorepc());
1168 reg_val = read_c0_cacheerr();
1169 printk("c0_cacheerr == %08x\n", reg_val);
1170
1171 printk("Decoded c0_cacheerr: %s cache fault in %s reference.\n",
1172 reg_val & (1<<30) ? "secondary" : "primary",
1173 reg_val & (1<<31) ? "data" : "insn");
1174 printk("Error bits: %s%s%s%s%s%s%s\n",
1175 reg_val & (1<<29) ? "ED " : "",
1176 reg_val & (1<<28) ? "ET " : "",
1177 reg_val & (1<<26) ? "EE " : "",
1178 reg_val & (1<<25) ? "EB " : "",
1179 reg_val & (1<<24) ? "EI " : "",
1180 reg_val & (1<<23) ? "E1 " : "",
1181 reg_val & (1<<22) ? "E0 " : "");
1182 printk("IDX: 0x%08x\n", reg_val & ((1<<22)-1));
1183
1184 #if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64)
1185 if (reg_val & (1<<22))
1186 printk("DErrAddr0: 0x%0*lx\n", field, read_c0_derraddr0());
1187
1188 if (reg_val & (1<<23))
1189 printk("DErrAddr1: 0x%0*lx\n", field, read_c0_derraddr1());
1190 #endif
1191
1192 panic("Can't handle the cache error!");
1193 }
1194
1195 /*
1196 * SDBBP EJTAG debug exception handler.
1197 * We skip the instruction and return to the next instruction.
1198 */
ejtag_exception_handler(struct pt_regs * regs)1199 void ejtag_exception_handler(struct pt_regs *regs)
1200 {
1201 const int field = 2 * sizeof(unsigned long);
1202 unsigned long depc, old_epc;
1203 unsigned int debug;
1204
1205 printk(KERN_DEBUG "SDBBP EJTAG debug exception - not handled yet, just ignored!\n");
1206 depc = read_c0_depc();
1207 debug = read_c0_debug();
1208 printk(KERN_DEBUG "c0_depc = %0*lx, DEBUG = %08x\n", field, depc, debug);
1209 if (debug & 0x80000000) {
1210 /*
1211 * In branch delay slot.
1212 * We cheat a little bit here and use EPC to calculate the
1213 * debug return address (DEPC). EPC is restored after the
1214 * calculation.
1215 */
1216 old_epc = regs->cp0_epc;
1217 regs->cp0_epc = depc;
1218 __compute_return_epc(regs);
1219 depc = regs->cp0_epc;
1220 regs->cp0_epc = old_epc;
1221 } else
1222 depc += 4;
1223 write_c0_depc(depc);
1224
1225 #if 0
1226 printk(KERN_DEBUG "\n\n----- Enable EJTAG single stepping ----\n\n");
1227 write_c0_debug(debug | 0x100);
1228 #endif
1229 }
1230
1231 /*
1232 * NMI exception handler.
1233 */
nmi_exception_handler(struct pt_regs * regs)1234 NORET_TYPE void ATTRIB_NORET nmi_exception_handler(struct pt_regs *regs)
1235 {
1236 bust_spinlocks(1);
1237 printk("NMI taken!!!!\n");
1238 die("NMI", regs);
1239 }
1240
1241 #define VECTORSPACING 0x100 /* for EI/VI mode */
1242
1243 unsigned long ebase;
1244 unsigned long exception_handlers[32];
1245 unsigned long vi_handlers[64];
1246
1247 /*
1248 * As a side effect of the way this is implemented we're limited
1249 * to interrupt handlers in the address range from
1250 * KSEG0 <= x < KSEG0 + 256mb on the Nevada. Oh well ...
1251 */
set_except_vector(int n,void * addr)1252 void *set_except_vector(int n, void *addr)
1253 {
1254 unsigned long handler = (unsigned long) addr;
1255 unsigned long old_handler = exception_handlers[n];
1256
1257 exception_handlers[n] = handler;
1258 if (n == 0 && cpu_has_divec) {
1259 *(u32 *)(ebase + 0x200) = 0x08000000 |
1260 (0x03ffffff & (handler >> 2));
1261 local_flush_icache_range(ebase + 0x200, ebase + 0x204);
1262 }
1263 return (void *)old_handler;
1264 }
1265
do_default_vi(void)1266 static asmlinkage void do_default_vi(void)
1267 {
1268 show_regs(get_irq_regs());
1269 panic("Caught unexpected vectored interrupt.");
1270 }
1271
set_vi_srs_handler(int n,vi_handler_t addr,int srs)1272 static void *set_vi_srs_handler(int n, vi_handler_t addr, int srs)
1273 {
1274 unsigned long handler;
1275 unsigned long old_handler = vi_handlers[n];
1276 int srssets = current_cpu_data.srsets;
1277 u32 *w;
1278 unsigned char *b;
1279
1280 if (!cpu_has_veic && !cpu_has_vint)
1281 BUG();
1282
1283 if (addr == NULL) {
1284 handler = (unsigned long) do_default_vi;
1285 srs = 0;
1286 } else
1287 handler = (unsigned long) addr;
1288 vi_handlers[n] = (unsigned long) addr;
1289
1290 b = (unsigned char *)(ebase + 0x200 + n*VECTORSPACING);
1291
1292 if (srs >= srssets)
1293 panic("Shadow register set %d not supported", srs);
1294
1295 if (cpu_has_veic) {
1296 if (board_bind_eic_interrupt)
1297 board_bind_eic_interrupt(n, srs);
1298 } else if (cpu_has_vint) {
1299 /* SRSMap is only defined if shadow sets are implemented */
1300 if (srssets > 1)
1301 change_c0_srsmap(0xf << n*4, srs << n*4);
1302 }
1303
1304 if (srs == 0) {
1305 /*
1306 * If no shadow set is selected then use the default handler
1307 * that does normal register saving and a standard interrupt exit
1308 */
1309
1310 extern char except_vec_vi, except_vec_vi_lui;
1311 extern char except_vec_vi_ori, except_vec_vi_end;
1312 extern char rollback_except_vec_vi;
1313 char *vec_start = (cpu_wait == r4k_wait) ?
1314 &rollback_except_vec_vi : &except_vec_vi;
1315 #ifdef CONFIG_MIPS_MT_SMTC
1316 /*
1317 * We need to provide the SMTC vectored interrupt handler
1318 * not only with the address of the handler, but with the
1319 * Status.IM bit to be masked before going there.
1320 */
1321 extern char except_vec_vi_mori;
1322 const int mori_offset = &except_vec_vi_mori - vec_start;
1323 #endif /* CONFIG_MIPS_MT_SMTC */
1324 const int handler_len = &except_vec_vi_end - vec_start;
1325 const int lui_offset = &except_vec_vi_lui - vec_start;
1326 const int ori_offset = &except_vec_vi_ori - vec_start;
1327
1328 if (handler_len > VECTORSPACING) {
1329 /*
1330 * Sigh... panicing won't help as the console
1331 * is probably not configured :(
1332 */
1333 panic("VECTORSPACING too small");
1334 }
1335
1336 memcpy(b, vec_start, handler_len);
1337 #ifdef CONFIG_MIPS_MT_SMTC
1338 BUG_ON(n > 7); /* Vector index %d exceeds SMTC maximum. */
1339
1340 w = (u32 *)(b + mori_offset);
1341 *w = (*w & 0xffff0000) | (0x100 << n);
1342 #endif /* CONFIG_MIPS_MT_SMTC */
1343 w = (u32 *)(b + lui_offset);
1344 *w = (*w & 0xffff0000) | (((u32)handler >> 16) & 0xffff);
1345 w = (u32 *)(b + ori_offset);
1346 *w = (*w & 0xffff0000) | ((u32)handler & 0xffff);
1347 local_flush_icache_range((unsigned long)b,
1348 (unsigned long)(b+handler_len));
1349 }
1350 else {
1351 /*
1352 * In other cases jump directly to the interrupt handler
1353 *
1354 * It is the handlers responsibility to save registers if required
1355 * (eg hi/lo) and return from the exception using "eret"
1356 */
1357 w = (u32 *)b;
1358 *w++ = 0x08000000 | (((u32)handler >> 2) & 0x03fffff); /* j handler */
1359 *w = 0;
1360 local_flush_icache_range((unsigned long)b,
1361 (unsigned long)(b+8));
1362 }
1363
1364 return (void *)old_handler;
1365 }
1366
set_vi_handler(int n,vi_handler_t addr)1367 void *set_vi_handler(int n, vi_handler_t addr)
1368 {
1369 return set_vi_srs_handler(n, addr, 0);
1370 }
1371
1372 /*
1373 * This is used by native signal handling
1374 */
1375 asmlinkage int (*save_fp_context)(struct sigcontext __user *sc);
1376 asmlinkage int (*restore_fp_context)(struct sigcontext __user *sc);
1377
1378 extern asmlinkage int _save_fp_context(struct sigcontext __user *sc);
1379 extern asmlinkage int _restore_fp_context(struct sigcontext __user *sc);
1380
1381 extern asmlinkage int fpu_emulator_save_context(struct sigcontext __user *sc);
1382 extern asmlinkage int fpu_emulator_restore_context(struct sigcontext __user *sc);
1383
1384 #ifdef CONFIG_SMP
smp_save_fp_context(struct sigcontext __user * sc)1385 static int smp_save_fp_context(struct sigcontext __user *sc)
1386 {
1387 return raw_cpu_has_fpu
1388 ? _save_fp_context(sc)
1389 : fpu_emulator_save_context(sc);
1390 }
1391
smp_restore_fp_context(struct sigcontext __user * sc)1392 static int smp_restore_fp_context(struct sigcontext __user *sc)
1393 {
1394 return raw_cpu_has_fpu
1395 ? _restore_fp_context(sc)
1396 : fpu_emulator_restore_context(sc);
1397 }
1398 #endif
1399
signal_init(void)1400 static inline void signal_init(void)
1401 {
1402 #ifdef CONFIG_SMP
1403 /* For now just do the cpu_has_fpu check when the functions are invoked */
1404 save_fp_context = smp_save_fp_context;
1405 restore_fp_context = smp_restore_fp_context;
1406 #else
1407 if (cpu_has_fpu) {
1408 save_fp_context = _save_fp_context;
1409 restore_fp_context = _restore_fp_context;
1410 } else {
1411 save_fp_context = fpu_emulator_save_context;
1412 restore_fp_context = fpu_emulator_restore_context;
1413 }
1414 #endif
1415 }
1416
1417 #ifdef CONFIG_MIPS32_COMPAT
1418
1419 /*
1420 * This is used by 32-bit signal stuff on the 64-bit kernel
1421 */
1422 asmlinkage int (*save_fp_context32)(struct sigcontext32 __user *sc);
1423 asmlinkage int (*restore_fp_context32)(struct sigcontext32 __user *sc);
1424
1425 extern asmlinkage int _save_fp_context32(struct sigcontext32 __user *sc);
1426 extern asmlinkage int _restore_fp_context32(struct sigcontext32 __user *sc);
1427
1428 extern asmlinkage int fpu_emulator_save_context32(struct sigcontext32 __user *sc);
1429 extern asmlinkage int fpu_emulator_restore_context32(struct sigcontext32 __user *sc);
1430
signal32_init(void)1431 static inline void signal32_init(void)
1432 {
1433 if (cpu_has_fpu) {
1434 save_fp_context32 = _save_fp_context32;
1435 restore_fp_context32 = _restore_fp_context32;
1436 } else {
1437 save_fp_context32 = fpu_emulator_save_context32;
1438 restore_fp_context32 = fpu_emulator_restore_context32;
1439 }
1440 }
1441 #endif
1442
1443 extern void cpu_cache_init(void);
1444 extern void tlb_init(void);
1445 extern void flush_tlb_handlers(void);
1446
1447 /*
1448 * Timer interrupt
1449 */
1450 int cp0_compare_irq;
1451
1452 /*
1453 * Performance counter IRQ or -1 if shared with timer
1454 */
1455 int cp0_perfcount_irq;
1456 EXPORT_SYMBOL_GPL(cp0_perfcount_irq);
1457
1458 static int __cpuinitdata noulri;
1459
ulri_disable(char * s)1460 static int __init ulri_disable(char *s)
1461 {
1462 pr_info("Disabling ulri\n");
1463 noulri = 1;
1464
1465 return 1;
1466 }
1467 __setup("noulri", ulri_disable);
1468
per_cpu_trap_init(void)1469 void __cpuinit per_cpu_trap_init(void)
1470 {
1471 unsigned int cpu = smp_processor_id();
1472 unsigned int status_set = ST0_CU0;
1473 #ifdef CONFIG_MIPS_MT_SMTC
1474 int secondaryTC = 0;
1475 int bootTC = (cpu == 0);
1476
1477 /*
1478 * Only do per_cpu_trap_init() for first TC of Each VPE.
1479 * Note that this hack assumes that the SMTC init code
1480 * assigns TCs consecutively and in ascending order.
1481 */
1482
1483 if (((read_c0_tcbind() & TCBIND_CURTC) != 0) &&
1484 ((read_c0_tcbind() & TCBIND_CURVPE) == cpu_data[cpu - 1].vpe_id))
1485 secondaryTC = 1;
1486 #endif /* CONFIG_MIPS_MT_SMTC */
1487
1488 /*
1489 * Disable coprocessors and select 32-bit or 64-bit addressing
1490 * and the 16/32 or 32/32 FPR register model. Reset the BEV
1491 * flag that some firmware may have left set and the TS bit (for
1492 * IP27). Set XX for ISA IV code to work.
1493 */
1494 #ifdef CONFIG_64BIT
1495 status_set |= ST0_FR|ST0_KX|ST0_SX|ST0_UX;
1496 #endif
1497 if (current_cpu_data.isa_level == MIPS_CPU_ISA_IV)
1498 status_set |= ST0_XX;
1499 if (cpu_has_dsp)
1500 status_set |= ST0_MX;
1501
1502 change_c0_status(ST0_CU|ST0_MX|ST0_RE|ST0_FR|ST0_BEV|ST0_TS|ST0_KX|ST0_SX|ST0_UX,
1503 status_set);
1504
1505 if (cpu_has_mips_r2) {
1506 unsigned int enable = 0x0000000f;
1507
1508 if (!noulri && cpu_has_userlocal)
1509 enable |= (1 << 29);
1510
1511 write_c0_hwrena(enable);
1512 }
1513
1514 #ifdef CONFIG_CPU_CAVIUM_OCTEON
1515 write_c0_hwrena(0xc000000f); /* Octeon has register 30 and 31 */
1516 #endif
1517
1518 #ifdef CONFIG_MIPS_MT_SMTC
1519 if (!secondaryTC) {
1520 #endif /* CONFIG_MIPS_MT_SMTC */
1521
1522 if (cpu_has_veic || cpu_has_vint) {
1523 write_c0_ebase(ebase);
1524 /* Setting vector spacing enables EI/VI mode */
1525 change_c0_intctl(0x3e0, VECTORSPACING);
1526 }
1527 if (cpu_has_divec) {
1528 if (cpu_has_mipsmt) {
1529 unsigned int vpflags = dvpe();
1530 set_c0_cause(CAUSEF_IV);
1531 evpe(vpflags);
1532 } else
1533 set_c0_cause(CAUSEF_IV);
1534 }
1535
1536 /*
1537 * Before R2 both interrupt numbers were fixed to 7, so on R2 only:
1538 *
1539 * o read IntCtl.IPTI to determine the timer interrupt
1540 * o read IntCtl.IPPCI to determine the performance counter interrupt
1541 */
1542 if (cpu_has_mips_r2) {
1543 cp0_compare_irq = (read_c0_intctl() >> 29) & 7;
1544 cp0_perfcount_irq = (read_c0_intctl() >> 26) & 7;
1545 if (cp0_perfcount_irq == cp0_compare_irq)
1546 cp0_perfcount_irq = -1;
1547 } else {
1548 cp0_compare_irq = CP0_LEGACY_COMPARE_IRQ;
1549 cp0_perfcount_irq = -1;
1550 }
1551
1552 #ifdef CONFIG_MIPS_MT_SMTC
1553 }
1554 #endif /* CONFIG_MIPS_MT_SMTC */
1555
1556 cpu_data[cpu].asid_cache = ASID_FIRST_VERSION;
1557 TLBMISS_HANDLER_SETUP();
1558
1559 atomic_inc(&init_mm.mm_count);
1560 current->active_mm = &init_mm;
1561 BUG_ON(current->mm);
1562 enter_lazy_tlb(&init_mm, current);
1563
1564 #ifdef CONFIG_MIPS_MT_SMTC
1565 if (bootTC) {
1566 #endif /* CONFIG_MIPS_MT_SMTC */
1567 cpu_cache_init();
1568 tlb_init();
1569 #ifdef CONFIG_MIPS_MT_SMTC
1570 } else if (!secondaryTC) {
1571 /*
1572 * First TC in non-boot VPE must do subset of tlb_init()
1573 * for MMU countrol registers.
1574 */
1575 write_c0_pagemask(PM_DEFAULT_MASK);
1576 write_c0_wired(0);
1577 }
1578 #endif /* CONFIG_MIPS_MT_SMTC */
1579 }
1580
1581 /* Install CPU exception handler */
set_handler(unsigned long offset,void * addr,unsigned long size)1582 void __init set_handler(unsigned long offset, void *addr, unsigned long size)
1583 {
1584 memcpy((void *)(ebase + offset), addr, size);
1585 local_flush_icache_range(ebase + offset, ebase + offset + size);
1586 }
1587
1588 static char panic_null_cerr[] __cpuinitdata =
1589 "Trying to set NULL cache error exception handler";
1590
1591 /*
1592 * Install uncached CPU exception handler.
1593 * This is suitable only for the cache error exception which is the only
1594 * exception handler that is being run uncached.
1595 */
set_uncached_handler(unsigned long offset,void * addr,unsigned long size)1596 void __cpuinit set_uncached_handler(unsigned long offset, void *addr,
1597 unsigned long size)
1598 {
1599 #ifdef CONFIG_32BIT
1600 unsigned long uncached_ebase = KSEG1ADDR(ebase);
1601 #endif
1602 #ifdef CONFIG_64BIT
1603 unsigned long uncached_ebase = TO_UNCAC(ebase);
1604 #endif
1605 if (cpu_has_mips_r2)
1606 uncached_ebase += (read_c0_ebase() & 0x3ffff000);
1607
1608 if (!addr)
1609 panic(panic_null_cerr);
1610
1611 memcpy((void *)(uncached_ebase + offset), addr, size);
1612 }
1613
1614 static int __initdata rdhwr_noopt;
set_rdhwr_noopt(char * str)1615 static int __init set_rdhwr_noopt(char *str)
1616 {
1617 rdhwr_noopt = 1;
1618 return 1;
1619 }
1620
1621 __setup("rdhwr_noopt", set_rdhwr_noopt);
1622
trap_init(void)1623 void __init trap_init(void)
1624 {
1625 extern char except_vec3_generic, except_vec3_r4000;
1626 extern char except_vec4;
1627 unsigned long i;
1628 int rollback;
1629
1630 check_wait();
1631 rollback = (cpu_wait == r4k_wait);
1632
1633 #if defined(CONFIG_KGDB)
1634 if (kgdb_early_setup)
1635 return; /* Already done */
1636 #endif
1637
1638 if (cpu_has_veic || cpu_has_vint)
1639 ebase = (unsigned long) alloc_bootmem_low_pages(0x200 + VECTORSPACING*64);
1640 else {
1641 ebase = CAC_BASE;
1642 if (cpu_has_mips_r2)
1643 ebase += (read_c0_ebase() & 0x3ffff000);
1644 }
1645
1646 per_cpu_trap_init();
1647
1648 /*
1649 * Copy the generic exception handlers to their final destination.
1650 * This will be overriden later as suitable for a particular
1651 * configuration.
1652 */
1653 set_handler(0x180, &except_vec3_generic, 0x80);
1654
1655 /*
1656 * Setup default vectors
1657 */
1658 for (i = 0; i <= 31; i++)
1659 set_except_vector(i, handle_reserved);
1660
1661 /*
1662 * Copy the EJTAG debug exception vector handler code to it's final
1663 * destination.
1664 */
1665 if (cpu_has_ejtag && board_ejtag_handler_setup)
1666 board_ejtag_handler_setup();
1667
1668 /*
1669 * Only some CPUs have the watch exceptions.
1670 */
1671 if (cpu_has_watch)
1672 set_except_vector(23, handle_watch);
1673
1674 /*
1675 * Initialise interrupt handlers
1676 */
1677 if (cpu_has_veic || cpu_has_vint) {
1678 int nvec = cpu_has_veic ? 64 : 8;
1679 for (i = 0; i < nvec; i++)
1680 set_vi_handler(i, NULL);
1681 }
1682 else if (cpu_has_divec)
1683 set_handler(0x200, &except_vec4, 0x8);
1684
1685 /*
1686 * Some CPUs can enable/disable for cache parity detection, but does
1687 * it different ways.
1688 */
1689 parity_protection_init();
1690
1691 /*
1692 * The Data Bus Errors / Instruction Bus Errors are signaled
1693 * by external hardware. Therefore these two exceptions
1694 * may have board specific handlers.
1695 */
1696 if (board_be_init)
1697 board_be_init();
1698
1699 set_except_vector(0, rollback ? rollback_handle_int : handle_int);
1700 set_except_vector(1, handle_tlbm);
1701 set_except_vector(2, handle_tlbl);
1702 set_except_vector(3, handle_tlbs);
1703
1704 set_except_vector(4, handle_adel);
1705 set_except_vector(5, handle_ades);
1706
1707 set_except_vector(6, handle_ibe);
1708 set_except_vector(7, handle_dbe);
1709
1710 set_except_vector(8, handle_sys);
1711 set_except_vector(9, handle_bp);
1712 set_except_vector(10, rdhwr_noopt ? handle_ri :
1713 (cpu_has_vtag_icache ?
1714 handle_ri_rdhwr_vivt : handle_ri_rdhwr));
1715 set_except_vector(11, handle_cpu);
1716 set_except_vector(12, handle_ov);
1717 set_except_vector(13, handle_tr);
1718
1719 if (current_cpu_type() == CPU_R6000 ||
1720 current_cpu_type() == CPU_R6000A) {
1721 /*
1722 * The R6000 is the only R-series CPU that features a machine
1723 * check exception (similar to the R4000 cache error) and
1724 * unaligned ldc1/sdc1 exception. The handlers have not been
1725 * written yet. Well, anyway there is no R6000 machine on the
1726 * current list of targets for Linux/MIPS.
1727 * (Duh, crap, there is someone with a triple R6k machine)
1728 */
1729 //set_except_vector(14, handle_mc);
1730 //set_except_vector(15, handle_ndc);
1731 }
1732
1733
1734 if (board_nmi_handler_setup)
1735 board_nmi_handler_setup();
1736
1737 if (cpu_has_fpu && !cpu_has_nofpuex)
1738 set_except_vector(15, handle_fpe);
1739
1740 set_except_vector(22, handle_mdmx);
1741
1742 if (cpu_has_mcheck)
1743 set_except_vector(24, handle_mcheck);
1744
1745 if (cpu_has_mipsmt)
1746 set_except_vector(25, handle_mt);
1747
1748 set_except_vector(26, handle_dsp);
1749
1750 if (cpu_has_vce)
1751 /* Special exception: R4[04]00 uses also the divec space. */
1752 memcpy((void *)(ebase + 0x180), &except_vec3_r4000, 0x100);
1753 else if (cpu_has_4kex)
1754 memcpy((void *)(ebase + 0x180), &except_vec3_generic, 0x80);
1755 else
1756 memcpy((void *)(ebase + 0x080), &except_vec3_generic, 0x80);
1757
1758 signal_init();
1759 #ifdef CONFIG_MIPS32_COMPAT
1760 signal32_init();
1761 #endif
1762
1763 local_flush_icache_range(ebase, ebase + 0x400);
1764 flush_tlb_handlers();
1765
1766 sort_extable(__start___dbe_table, __stop___dbe_table);
1767 }
1768