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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[linux-btrfs-devel.git] / arch / powerpc / kernel / traps.c
blobf19d9777d3c1825d01b9f0dde217ade0ddd80344
1 /*
2 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
3 * Copyright 2007-2010 Freescale Semiconductor, Inc.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation; either version
8 * 2 of the License, or (at your option) any later version.
9 *
10 * Modified by Cort Dougan (cort@cs.nmt.edu)
11 * and Paul Mackerras (paulus@samba.org)
12 */
13
14 /*
15 * This file handles the architecture-dependent parts of hardware exceptions
16 */
17
18 #include <linux/errno.h>
19 #include <linux/sched.h>
20 #include <linux/kernel.h>
21 #include <linux/mm.h>
22 #include <linux/stddef.h>
23 #include <linux/unistd.h>
24 #include <linux/ptrace.h>
25 #include <linux/user.h>
26 #include <linux/interrupt.h>
27 #include <linux/init.h>
28 #include <linux/module.h>
29 #include <linux/prctl.h>
30 #include <linux/delay.h>
31 #include <linux/kprobes.h>
32 #include <linux/kexec.h>
33 #include <linux/backlight.h>
34 #include <linux/bug.h>
35 #include <linux/kdebug.h>
36 #include <linux/debugfs.h>
37 #include <linux/ratelimit.h>
38
39 #include <asm/emulated_ops.h>
40 #include <asm/pgtable.h>
41 #include <asm/uaccess.h>
42 #include <asm/system.h>
43 #include <asm/io.h>
44 #include <asm/machdep.h>
45 #include <asm/rtas.h>
46 #include <asm/pmc.h>
47 #ifdef CONFIG_PPC32
48 #include <asm/reg.h>
49 #endif
50 #ifdef CONFIG_PMAC_BACKLIGHT
51 #include <asm/backlight.h>
52 #endif
53 #ifdef CONFIG_PPC64
54 #include <asm/firmware.h>
55 #include <asm/processor.h>
56 #endif
57 #include <asm/kexec.h>
58 #include <asm/ppc-opcode.h>
59 #include <asm/rio.h>
60
61 #if defined(CONFIG_DEBUGGER) || defined(CONFIG_KEXEC)
62 int (*__debugger)(struct pt_regs *regs) __read_mostly;
63 int (*__debugger_ipi)(struct pt_regs *regs) __read_mostly;
64 int (*__debugger_bpt)(struct pt_regs *regs) __read_mostly;
65 int (*__debugger_sstep)(struct pt_regs *regs) __read_mostly;
66 int (*__debugger_iabr_match)(struct pt_regs *regs) __read_mostly;
67 int (*__debugger_dabr_match)(struct pt_regs *regs) __read_mostly;
68 int (*__debugger_fault_handler)(struct pt_regs *regs) __read_mostly;
69
70 EXPORT_SYMBOL(__debugger);
71 EXPORT_SYMBOL(__debugger_ipi);
72 EXPORT_SYMBOL(__debugger_bpt);
73 EXPORT_SYMBOL(__debugger_sstep);
74 EXPORT_SYMBOL(__debugger_iabr_match);
75 EXPORT_SYMBOL(__debugger_dabr_match);
76 EXPORT_SYMBOL(__debugger_fault_handler);
77 #endif
78
79 /*
80 * Trap & Exception support
81 */
82
83 #ifdef CONFIG_PMAC_BACKLIGHT
84 static void pmac_backlight_unblank(void)
85 {
86 mutex_lock(&pmac_backlight_mutex);
87 if (pmac_backlight) {
88 struct backlight_properties *props;
89
90 props = &pmac_backlight->props;
91 props->brightness = props->max_brightness;
92 props->power = FB_BLANK_UNBLANK;
93 backlight_update_status(pmac_backlight);
94 }
95 mutex_unlock(&pmac_backlight_mutex);
96 }
97 #else
98 static inline void pmac_backlight_unblank(void) { }
99 #endif
100
101 int die(const char *str, struct pt_regs *regs, long err)
102 {
103 static struct {
104 raw_spinlock_t lock;
105 u32 lock_owner;
106 int lock_owner_depth;
107 } die = {
108 .lock = __RAW_SPIN_LOCK_UNLOCKED(die.lock),
109 .lock_owner = -1,
110 .lock_owner_depth = 0
111 };
112 static int die_counter;
113 unsigned long flags;
114
115 if (debugger(regs))
116 return 1;
117
118 oops_enter();
119
120 if (die.lock_owner != raw_smp_processor_id()) {
121 console_verbose();
122 raw_spin_lock_irqsave(&die.lock, flags);
123 die.lock_owner = smp_processor_id();
124 die.lock_owner_depth = 0;
125 bust_spinlocks(1);
126 if (machine_is(powermac))
127 pmac_backlight_unblank();
128 } else {
129 local_save_flags(flags);
130 }
131
132 if (++die.lock_owner_depth < 3) {
133 printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
134 #ifdef CONFIG_PREEMPT
135 printk("PREEMPT ");
136 #endif
137 #ifdef CONFIG_SMP
138 printk("SMP NR_CPUS=%d ", NR_CPUS);
139 #endif
140 #ifdef CONFIG_DEBUG_PAGEALLOC
141 printk("DEBUG_PAGEALLOC ");
142 #endif
143 #ifdef CONFIG_NUMA
144 printk("NUMA ");
145 #endif
146 printk("%s\n", ppc_md.name ? ppc_md.name : "");
147
148 if (notify_die(DIE_OOPS, str, regs, err, 255,
149 SIGSEGV) == NOTIFY_STOP)
150 return 1;
151
152 print_modules();
153 show_regs(regs);
154 } else {
155 printk("Recursive die() failure, output suppressed\n");
156 }
157
158 bust_spinlocks(0);
159 die.lock_owner = -1;
160 add_taint(TAINT_DIE);
161 raw_spin_unlock_irqrestore(&die.lock, flags);
162
163 if (kexec_should_crash(current) ||
164 kexec_sr_activated(smp_processor_id()))
165 crash_kexec(regs);
166 crash_kexec_secondary(regs);
167
168 if (in_interrupt())
169 panic("Fatal exception in interrupt");
170
171 if (panic_on_oops)
172 panic("Fatal exception");
173
174 oops_exit();
175 do_exit(err);
176
177 return 0;
178 }
179
180 void user_single_step_siginfo(struct task_struct *tsk,
181 struct pt_regs *regs, siginfo_t *info)
182 {
183 memset(info, 0, sizeof(*info));
184 info->si_signo = SIGTRAP;
185 info->si_code = TRAP_TRACE;
186 info->si_addr = (void __user *)regs->nip;
187 }
188
189 void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
190 {
191 siginfo_t info;
192 const char fmt32[] = KERN_INFO "%s[%d]: unhandled signal %d " \
193 "at %08lx nip %08lx lr %08lx code %x\n";
194 const char fmt64[] = KERN_INFO "%s[%d]: unhandled signal %d " \
195 "at %016lx nip %016lx lr %016lx code %x\n";
196
197 if (!user_mode(regs)) {
198 if (die("Exception in kernel mode", regs, signr))
199 return;
200 } else if (show_unhandled_signals &&
201 unhandled_signal(current, signr)) {
202 printk_ratelimited(regs->msr & MSR_64BIT ? fmt64 : fmt32,
203 current->comm, current->pid, signr,
204 addr, regs->nip, regs->link, code);
205 }
206
207 memset(&info, 0, sizeof(info));
208 info.si_signo = signr;
209 info.si_code = code;
210 info.si_addr = (void __user *) addr;
211 force_sig_info(signr, &info, current);
212 }
213
214 #ifdef CONFIG_PPC64
215 void system_reset_exception(struct pt_regs *regs)
216 {
217 /* See if any machine dependent calls */
218 if (ppc_md.system_reset_exception) {
219 if (ppc_md.system_reset_exception(regs))
220 return;
221 }
222
223 #ifdef CONFIG_KEXEC
224 cpumask_set_cpu(smp_processor_id(), &cpus_in_sr);
225 #endif
226
227 die("System Reset", regs, SIGABRT);
228
229 /*
230 * Some CPUs when released from the debugger will execute this path.
231 * These CPUs entered the debugger via a soft-reset. If the CPU was
232 * hung before entering the debugger it will return to the hung
233 * state when exiting this function. This causes a problem in
234 * kdump since the hung CPU(s) will not respond to the IPI sent
235 * from kdump. To prevent the problem we call crash_kexec_secondary()
236 * here. If a kdump had not been initiated or we exit the debugger
237 * with the "exit and recover" command (x) crash_kexec_secondary()
238 * will return after 5ms and the CPU returns to its previous state.
239 */
240 crash_kexec_secondary(regs);
241
242 /* Must die if the interrupt is not recoverable */
243 if (!(regs->msr & MSR_RI))
244 panic("Unrecoverable System Reset");
245
246 /* What should we do here? We could issue a shutdown or hard reset. */
247 }
248 #endif
249
250 /*
251 * I/O accesses can cause machine checks on powermacs.
252 * Check if the NIP corresponds to the address of a sync
253 * instruction for which there is an entry in the exception
254 * table.
255 * Note that the 601 only takes a machine check on TEA
256 * (transfer error ack) signal assertion, and does not
257 * set any of the top 16 bits of SRR1.
258 * -- paulus.
259 */
260 static inline int check_io_access(struct pt_regs *regs)
261 {
262 #ifdef CONFIG_PPC32
263 unsigned long msr = regs->msr;
264 const struct exception_table_entry *entry;
265 unsigned int *nip = (unsigned int *)regs->nip;
266
267 if (((msr & 0xffff0000) == 0 || (msr & (0x80000 | 0x40000)))
268 && (entry = search_exception_tables(regs->nip)) != NULL) {
269 /*
270 * Check that it's a sync instruction, or somewhere
271 * in the twi; isync; nop sequence that inb/inw/inl uses.
272 * As the address is in the exception table
273 * we should be able to read the instr there.
274 * For the debug message, we look at the preceding
275 * load or store.
276 */
277 if (*nip == 0x60000000) /* nop */
278 nip -= 2;
279 else if (*nip == 0x4c00012c) /* isync */
280 --nip;
281 if (*nip == 0x7c0004ac || (*nip >> 26) == 3) {
282 /* sync or twi */
283 unsigned int rb;
284
285 --nip;
286 rb = (*nip >> 11) & 0x1f;
287 printk(KERN_DEBUG "%s bad port %lx at %p\n",
288 (*nip & 0x100)? "OUT to": "IN from",
289 regs->gpr[rb] - _IO_BASE, nip);
290 regs->msr |= MSR_RI;
291 regs->nip = entry->fixup;
292 return 1;
293 }
294 }
295 #endif /* CONFIG_PPC32 */
296 return 0;
297 }
298
299 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
300 /* On 4xx, the reason for the machine check or program exception
301 is in the ESR. */
302 #define get_reason(regs) ((regs)->dsisr)
303 #ifndef CONFIG_FSL_BOOKE
304 #define get_mc_reason(regs) ((regs)->dsisr)
305 #else
306 #define get_mc_reason(regs) (mfspr(SPRN_MCSR))
307 #endif
308 #define REASON_FP ESR_FP
309 #define REASON_ILLEGAL (ESR_PIL | ESR_PUO)
310 #define REASON_PRIVILEGED ESR_PPR
311 #define REASON_TRAP ESR_PTR
312
313 /* single-step stuff */
314 #define single_stepping(regs) (current->thread.dbcr0 & DBCR0_IC)
315 #define clear_single_step(regs) (current->thread.dbcr0 &= ~DBCR0_IC)
316
317 #else
318 /* On non-4xx, the reason for the machine check or program
319 exception is in the MSR. */
320 #define get_reason(regs) ((regs)->msr)
321 #define get_mc_reason(regs) ((regs)->msr)
322 #define REASON_FP 0x100000
323 #define REASON_ILLEGAL 0x80000
324 #define REASON_PRIVILEGED 0x40000
325 #define REASON_TRAP 0x20000
326
327 #define single_stepping(regs) ((regs)->msr & MSR_SE)
328 #define clear_single_step(regs) ((regs)->msr &= ~MSR_SE)
329 #endif
330
331 #if defined(CONFIG_4xx)
332 int machine_check_4xx(struct pt_regs *regs)
333 {
334 unsigned long reason = get_mc_reason(regs);
335
336 if (reason & ESR_IMCP) {
337 printk("Instruction");
338 mtspr(SPRN_ESR, reason & ~ESR_IMCP);
339 } else
340 printk("Data");
341 printk(" machine check in kernel mode.\n");
342
343 return 0;
344 }
345
346 int machine_check_440A(struct pt_regs *regs)
347 {
348 unsigned long reason = get_mc_reason(regs);
349
350 printk("Machine check in kernel mode.\n");
351 if (reason & ESR_IMCP){
352 printk("Instruction Synchronous Machine Check exception\n");
353 mtspr(SPRN_ESR, reason & ~ESR_IMCP);
354 }
355 else {
356 u32 mcsr = mfspr(SPRN_MCSR);
357 if (mcsr & MCSR_IB)
358 printk("Instruction Read PLB Error\n");
359 if (mcsr & MCSR_DRB)
360 printk("Data Read PLB Error\n");
361 if (mcsr & MCSR_DWB)
362 printk("Data Write PLB Error\n");
363 if (mcsr & MCSR_TLBP)
364 printk("TLB Parity Error\n");
365 if (mcsr & MCSR_ICP){
366 flush_instruction_cache();
367 printk("I-Cache Parity Error\n");
368 }
369 if (mcsr & MCSR_DCSP)
370 printk("D-Cache Search Parity Error\n");
371 if (mcsr & MCSR_DCFP)
372 printk("D-Cache Flush Parity Error\n");
373 if (mcsr & MCSR_IMPE)
374 printk("Machine Check exception is imprecise\n");
375
376 /* Clear MCSR */
377 mtspr(SPRN_MCSR, mcsr);
378 }
379 return 0;
380 }
381
382 int machine_check_47x(struct pt_regs *regs)
383 {
384 unsigned long reason = get_mc_reason(regs);
385 u32 mcsr;
386
387 printk(KERN_ERR "Machine check in kernel mode.\n");
388 if (reason & ESR_IMCP) {
389 printk(KERN_ERR
390 "Instruction Synchronous Machine Check exception\n");
391 mtspr(SPRN_ESR, reason & ~ESR_IMCP);
392 return 0;
393 }
394 mcsr = mfspr(SPRN_MCSR);
395 if (mcsr & MCSR_IB)
396 printk(KERN_ERR "Instruction Read PLB Error\n");
397 if (mcsr & MCSR_DRB)
398 printk(KERN_ERR "Data Read PLB Error\n");
399 if (mcsr & MCSR_DWB)
400 printk(KERN_ERR "Data Write PLB Error\n");
401 if (mcsr & MCSR_TLBP)
402 printk(KERN_ERR "TLB Parity Error\n");
403 if (mcsr & MCSR_ICP) {
404 flush_instruction_cache();
405 printk(KERN_ERR "I-Cache Parity Error\n");
406 }
407 if (mcsr & MCSR_DCSP)
408 printk(KERN_ERR "D-Cache Search Parity Error\n");
409 if (mcsr & PPC47x_MCSR_GPR)
410 printk(KERN_ERR "GPR Parity Error\n");
411 if (mcsr & PPC47x_MCSR_FPR)
412 printk(KERN_ERR "FPR Parity Error\n");
413 if (mcsr & PPC47x_MCSR_IPR)
414 printk(KERN_ERR "Machine Check exception is imprecise\n");
415
416 /* Clear MCSR */
417 mtspr(SPRN_MCSR, mcsr);
418
419 return 0;
420 }
421 #elif defined(CONFIG_E500)
422 int machine_check_e500mc(struct pt_regs *regs)
423 {
424 unsigned long mcsr = mfspr(SPRN_MCSR);
425 unsigned long reason = mcsr;
426 int recoverable = 1;
427
428 if (reason & MCSR_LD) {
429 recoverable = fsl_rio_mcheck_exception(regs);
430 if (recoverable == 1)
431 goto silent_out;
432 }
433
434 printk("Machine check in kernel mode.\n");
435 printk("Caused by (from MCSR=%lx): ", reason);
436
437 if (reason & MCSR_MCP)
438 printk("Machine Check Signal\n");
439
440 if (reason & MCSR_ICPERR) {
441 printk("Instruction Cache Parity Error\n");
442
443 /*
444 * This is recoverable by invalidating the i-cache.
445 */
446 mtspr(SPRN_L1CSR1, mfspr(SPRN_L1CSR1) | L1CSR1_ICFI);
447 while (mfspr(SPRN_L1CSR1) & L1CSR1_ICFI)
448 ;
449
450 /*
451 * This will generally be accompanied by an instruction
452 * fetch error report -- only treat MCSR_IF as fatal
453 * if it wasn't due to an L1 parity error.
454 */
455 reason &= ~MCSR_IF;
456 }
457
458 if (reason & MCSR_DCPERR_MC) {
459 printk("Data Cache Parity Error\n");
460 recoverable = 0;
461 }
462
463 if (reason & MCSR_L2MMU_MHIT) {
464 printk("Hit on multiple TLB entries\n");
465 recoverable = 0;
466 }
467
468 if (reason & MCSR_NMI)
469 printk("Non-maskable interrupt\n");
470
471 if (reason & MCSR_IF) {
472 printk("Instruction Fetch Error Report\n");
473 recoverable = 0;
474 }
475
476 if (reason & MCSR_LD) {
477 printk("Load Error Report\n");
478 recoverable = 0;
479 }
480
481 if (reason & MCSR_ST) {
482 printk("Store Error Report\n");
483 recoverable = 0;
484 }
485
486 if (reason & MCSR_LDG) {
487 printk("Guarded Load Error Report\n");
488 recoverable = 0;
489 }
490
491 if (reason & MCSR_TLBSYNC)
492 printk("Simultaneous tlbsync operations\n");
493
494 if (reason & MCSR_BSL2_ERR) {
495 printk("Level 2 Cache Error\n");
496 recoverable = 0;
497 }
498
499 if (reason & MCSR_MAV) {
500 u64 addr;
501
502 addr = mfspr(SPRN_MCAR);
503 addr |= (u64)mfspr(SPRN_MCARU) << 32;
504
505 printk("Machine Check %s Address: %#llx\n",
506 reason & MCSR_MEA ? "Effective" : "Physical", addr);
507 }
508
509 silent_out:
510 mtspr(SPRN_MCSR, mcsr);
511 return mfspr(SPRN_MCSR) == 0 && recoverable;
512 }
513
514 int machine_check_e500(struct pt_regs *regs)
515 {
516 unsigned long reason = get_mc_reason(regs);
517
518 if (reason & MCSR_BUS_RBERR) {
519 if (fsl_rio_mcheck_exception(regs))
520 return 1;
521 }
522
523 printk("Machine check in kernel mode.\n");
524 printk("Caused by (from MCSR=%lx): ", reason);
525
526 if (reason & MCSR_MCP)
527 printk("Machine Check Signal\n");
528 if (reason & MCSR_ICPERR)
529 printk("Instruction Cache Parity Error\n");
530 if (reason & MCSR_DCP_PERR)
531 printk("Data Cache Push Parity Error\n");
532 if (reason & MCSR_DCPERR)
533 printk("Data Cache Parity Error\n");
534 if (reason & MCSR_BUS_IAERR)
535 printk("Bus - Instruction Address Error\n");
536 if (reason & MCSR_BUS_RAERR)
537 printk("Bus - Read Address Error\n");
538 if (reason & MCSR_BUS_WAERR)
539 printk("Bus - Write Address Error\n");
540 if (reason & MCSR_BUS_IBERR)
541 printk("Bus - Instruction Data Error\n");
542 if (reason & MCSR_BUS_RBERR)
543 printk("Bus - Read Data Bus Error\n");
544 if (reason & MCSR_BUS_WBERR)
545 printk("Bus - Read Data Bus Error\n");
546 if (reason & MCSR_BUS_IPERR)
547 printk("Bus - Instruction Parity Error\n");
548 if (reason & MCSR_BUS_RPERR)
549 printk("Bus - Read Parity Error\n");
550
551 return 0;
552 }
553
554 int machine_check_generic(struct pt_regs *regs)
555 {
556 return 0;
557 }
558 #elif defined(CONFIG_E200)
559 int machine_check_e200(struct pt_regs *regs)
560 {
561 unsigned long reason = get_mc_reason(regs);
562
563 printk("Machine check in kernel mode.\n");
564 printk("Caused by (from MCSR=%lx): ", reason);
565
566 if (reason & MCSR_MCP)
567 printk("Machine Check Signal\n");
568 if (reason & MCSR_CP_PERR)
569 printk("Cache Push Parity Error\n");
570 if (reason & MCSR_CPERR)
571 printk("Cache Parity Error\n");
572 if (reason & MCSR_EXCP_ERR)
573 printk("ISI, ITLB, or Bus Error on first instruction fetch for an exception handler\n");
574 if (reason & MCSR_BUS_IRERR)
575 printk("Bus - Read Bus Error on instruction fetch\n");
576 if (reason & MCSR_BUS_DRERR)
577 printk("Bus - Read Bus Error on data load\n");
578 if (reason & MCSR_BUS_WRERR)
579 printk("Bus - Write Bus Error on buffered store or cache line push\n");
580
581 return 0;
582 }
583 #else
584 int machine_check_generic(struct pt_regs *regs)
585 {
586 unsigned long reason = get_mc_reason(regs);
587
588 printk("Machine check in kernel mode.\n");
589 printk("Caused by (from SRR1=%lx): ", reason);
590 switch (reason & 0x601F0000) {
591 case 0x80000:
592 printk("Machine check signal\n");
593 break;
594 case 0: /* for 601 */
595 case 0x40000:
596 case 0x140000: /* 7450 MSS error and TEA */
597 printk("Transfer error ack signal\n");
598 break;
599 case 0x20000:
600 printk("Data parity error signal\n");
601 break;
602 case 0x10000:
603 printk("Address parity error signal\n");
604 break;
605 case 0x20000000:
606 printk("L1 Data Cache error\n");
607 break;
608 case 0x40000000:
609 printk("L1 Instruction Cache error\n");
610 break;
611 case 0x00100000:
612 printk("L2 data cache parity error\n");
613 break;
614 default:
615 printk("Unknown values in msr\n");
616 }
617 return 0;
618 }
619 #endif /* everything else */
620
621 void machine_check_exception(struct pt_regs *regs)
622 {
623 int recover = 0;
624
625 __get_cpu_var(irq_stat).mce_exceptions++;
626
627 /* See if any machine dependent calls. In theory, we would want
628 * to call the CPU first, and call the ppc_md. one if the CPU
629 * one returns a positive number. However there is existing code
630 * that assumes the board gets a first chance, so let's keep it
631 * that way for now and fix things later. --BenH.
632 */
633 if (ppc_md.machine_check_exception)
634 recover = ppc_md.machine_check_exception(regs);
635 else if (cur_cpu_spec->machine_check)
636 recover = cur_cpu_spec->machine_check(regs);
637
638 if (recover > 0)
639 return;
640
641 #if defined(CONFIG_8xx) && defined(CONFIG_PCI)
642 /* the qspan pci read routines can cause machine checks -- Cort
643 *
644 * yuck !!! that totally needs to go away ! There are better ways
645 * to deal with that than having a wart in the mcheck handler.
646 * -- BenH
647 */
648 bad_page_fault(regs, regs->dar, SIGBUS);
649 return;
650 #endif
651
652 if (debugger_fault_handler(regs))
653 return;
654
655 if (check_io_access(regs))
656 return;
657
658 die("Machine check", regs, SIGBUS);
659
660 /* Must die if the interrupt is not recoverable */
661 if (!(regs->msr & MSR_RI))
662 panic("Unrecoverable Machine check");
663 }
664
665 void SMIException(struct pt_regs *regs)
666 {
667 die("System Management Interrupt", regs, SIGABRT);
668 }
669
670 void unknown_exception(struct pt_regs *regs)
671 {
672 printk("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
673 regs->nip, regs->msr, regs->trap);
674
675 _exception(SIGTRAP, regs, 0, 0);
676 }
677
678 void instruction_breakpoint_exception(struct pt_regs *regs)
679 {
680 if (notify_die(DIE_IABR_MATCH, "iabr_match", regs, 5,
681 5, SIGTRAP) == NOTIFY_STOP)
682 return;
683 if (debugger_iabr_match(regs))
684 return;
685 _exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip);
686 }
687
688 void RunModeException(struct pt_regs *regs)
689 {
690 _exception(SIGTRAP, regs, 0, 0);
691 }
692
693 void __kprobes single_step_exception(struct pt_regs *regs)
694 {
695 clear_single_step(regs);
696
697 if (notify_die(DIE_SSTEP, "single_step", regs, 5,
698 5, SIGTRAP) == NOTIFY_STOP)
699 return;
700 if (debugger_sstep(regs))
701 return;
702
703 _exception(SIGTRAP, regs, TRAP_TRACE, regs->nip);
704 }
705
706 /*
707 * After we have successfully emulated an instruction, we have to
708 * check if the instruction was being single-stepped, and if so,
709 * pretend we got a single-step exception. This was pointed out
710 * by Kumar Gala. -- paulus
711 */
712 static void emulate_single_step(struct pt_regs *regs)
713 {
714 if (single_stepping(regs))
715 single_step_exception(regs);
716 }
717
718 static inline int __parse_fpscr(unsigned long fpscr)
719 {
720 int ret = 0;
721
722 /* Invalid operation */
723 if ((fpscr & FPSCR_VE) && (fpscr & FPSCR_VX))
724 ret = FPE_FLTINV;
725
726 /* Overflow */
727 else if ((fpscr & FPSCR_OE) && (fpscr & FPSCR_OX))
728 ret = FPE_FLTOVF;
729
730 /* Underflow */
731 else if ((fpscr & FPSCR_UE) && (fpscr & FPSCR_UX))
732 ret = FPE_FLTUND;
733
734 /* Divide by zero */
735 else if ((fpscr & FPSCR_ZE) && (fpscr & FPSCR_ZX))
736 ret = FPE_FLTDIV;
737
738 /* Inexact result */
739 else if ((fpscr & FPSCR_XE) && (fpscr & FPSCR_XX))
740 ret = FPE_FLTRES;
741
742 return ret;
743 }
744
745 static void parse_fpe(struct pt_regs *regs)
746 {
747 int code = 0;
748
749 flush_fp_to_thread(current);
750
751 code = __parse_fpscr(current->thread.fpscr.val);
752
753 _exception(SIGFPE, regs, code, regs->nip);
754 }
755
756 /*
757 * Illegal instruction emulation support. Originally written to
758 * provide the PVR to user applications using the mfspr rd, PVR.
759 * Return non-zero if we can't emulate, or -EFAULT if the associated
760 * memory access caused an access fault. Return zero on success.
761 *
762 * There are a couple of ways to do this, either "decode" the instruction
763 * or directly match lots of bits. In this case, matching lots of
764 * bits is faster and easier.
765 *
766 */
767 static int emulate_string_inst(struct pt_regs *regs, u32 instword)
768 {
769 u8 rT = (instword >> 21) & 0x1f;
770 u8 rA = (instword >> 16) & 0x1f;
771 u8 NB_RB = (instword >> 11) & 0x1f;
772 u32 num_bytes;
773 unsigned long EA;
774 int pos = 0;
775
776 /* Early out if we are an invalid form of lswx */
777 if ((instword & PPC_INST_STRING_MASK) == PPC_INST_LSWX)
778 if ((rT == rA) || (rT == NB_RB))
779 return -EINVAL;
780
781 EA = (rA == 0) ? 0 : regs->gpr[rA];
782
783 switch (instword & PPC_INST_STRING_MASK) {
784 case PPC_INST_LSWX:
785 case PPC_INST_STSWX:
786 EA += NB_RB;
787 num_bytes = regs->xer & 0x7f;
788 break;
789 case PPC_INST_LSWI:
790 case PPC_INST_STSWI:
791 num_bytes = (NB_RB == 0) ? 32 : NB_RB;
792 break;
793 default:
794 return -EINVAL;
795 }
796
797 while (num_bytes != 0)
798 {
799 u8 val;
800 u32 shift = 8 * (3 - (pos & 0x3));
801
802 switch ((instword & PPC_INST_STRING_MASK)) {
803 case PPC_INST_LSWX:
804 case PPC_INST_LSWI:
805 if (get_user(val, (u8 __user *)EA))
806 return -EFAULT;
807 /* first time updating this reg,
808 * zero it out */
809 if (pos == 0)
810 regs->gpr[rT] = 0;
811 regs->gpr[rT] |= val << shift;
812 break;
813 case PPC_INST_STSWI:
814 case PPC_INST_STSWX:
815 val = regs->gpr[rT] >> shift;
816 if (put_user(val, (u8 __user *)EA))
817 return -EFAULT;
818 break;
819 }
820 /* move EA to next address */
821 EA += 1;
822 num_bytes--;
823
824 /* manage our position within the register */
825 if (++pos == 4) {
826 pos = 0;
827 if (++rT == 32)
828 rT = 0;
829 }
830 }
831
832 return 0;
833 }
834
835 static int emulate_popcntb_inst(struct pt_regs *regs, u32 instword)
836 {
837 u32 ra,rs;
838 unsigned long tmp;
839
840 ra = (instword >> 16) & 0x1f;
841 rs = (instword >> 21) & 0x1f;
842
843 tmp = regs->gpr[rs];
844 tmp = tmp - ((tmp >> 1) & 0x5555555555555555ULL);
845 tmp = (tmp & 0x3333333333333333ULL) + ((tmp >> 2) & 0x3333333333333333ULL);
846 tmp = (tmp + (tmp >> 4)) & 0x0f0f0f0f0f0f0f0fULL;
847 regs->gpr[ra] = tmp;
848
849 return 0;
850 }
851
852 static int emulate_isel(struct pt_regs *regs, u32 instword)
853 {
854 u8 rT = (instword >> 21) & 0x1f;
855 u8 rA = (instword >> 16) & 0x1f;
856 u8 rB = (instword >> 11) & 0x1f;
857 u8 BC = (instword >> 6) & 0x1f;
858 u8 bit;
859 unsigned long tmp;
860
861 tmp = (rA == 0) ? 0 : regs->gpr[rA];
862 bit = (regs->ccr >> (31 - BC)) & 0x1;
863
864 regs->gpr[rT] = bit ? tmp : regs->gpr[rB];
865
866 return 0;
867 }
868
869 static int emulate_instruction(struct pt_regs *regs)
870 {
871 u32 instword;
872 u32 rd;
873
874 if (!user_mode(regs) || (regs->msr & MSR_LE))
875 return -EINVAL;
876 CHECK_FULL_REGS(regs);
877
878 if (get_user(instword, (u32 __user *)(regs->nip)))
879 return -EFAULT;
880
881 /* Emulate the mfspr rD, PVR. */
882 if ((instword & PPC_INST_MFSPR_PVR_MASK) == PPC_INST_MFSPR_PVR) {
883 PPC_WARN_EMULATED(mfpvr, regs);
884 rd = (instword >> 21) & 0x1f;
885 regs->gpr[rd] = mfspr(SPRN_PVR);
886 return 0;
887 }
888
889 /* Emulating the dcba insn is just a no-op. */
890 if ((instword & PPC_INST_DCBA_MASK) == PPC_INST_DCBA) {
891 PPC_WARN_EMULATED(dcba, regs);
892 return 0;
893 }
894
895 /* Emulate the mcrxr insn. */
896 if ((instword & PPC_INST_MCRXR_MASK) == PPC_INST_MCRXR) {
897 int shift = (instword >> 21) & 0x1c;
898 unsigned long msk = 0xf0000000UL >> shift;
899
900 PPC_WARN_EMULATED(mcrxr, regs);
901 regs->ccr = (regs->ccr & ~msk) | ((regs->xer >> shift) & msk);
902 regs->xer &= ~0xf0000000UL;
903 return 0;
904 }
905
906 /* Emulate load/store string insn. */
907 if ((instword & PPC_INST_STRING_GEN_MASK) == PPC_INST_STRING) {
908 PPC_WARN_EMULATED(string, regs);
909 return emulate_string_inst(regs, instword);
910 }
911
912 /* Emulate the popcntb (Population Count Bytes) instruction. */
913 if ((instword & PPC_INST_POPCNTB_MASK) == PPC_INST_POPCNTB) {
914 PPC_WARN_EMULATED(popcntb, regs);
915 return emulate_popcntb_inst(regs, instword);
916 }
917
918 /* Emulate isel (Integer Select) instruction */
919 if ((instword & PPC_INST_ISEL_MASK) == PPC_INST_ISEL) {
920 PPC_WARN_EMULATED(isel, regs);
921 return emulate_isel(regs, instword);
922 }
923
924 #ifdef CONFIG_PPC64
925 /* Emulate the mfspr rD, DSCR. */
926 if (((instword & PPC_INST_MFSPR_DSCR_MASK) == PPC_INST_MFSPR_DSCR) &&
927 cpu_has_feature(CPU_FTR_DSCR)) {
928 PPC_WARN_EMULATED(mfdscr, regs);
929 rd = (instword >> 21) & 0x1f;
930 regs->gpr[rd] = mfspr(SPRN_DSCR);
931 return 0;
932 }
933 /* Emulate the mtspr DSCR, rD. */
934 if (((instword & PPC_INST_MTSPR_DSCR_MASK) == PPC_INST_MTSPR_DSCR) &&
935 cpu_has_feature(CPU_FTR_DSCR)) {
936 PPC_WARN_EMULATED(mtdscr, regs);
937 rd = (instword >> 21) & 0x1f;
938 mtspr(SPRN_DSCR, regs->gpr[rd]);
939 current->thread.dscr_inherit = 1;
940 return 0;
941 }
942 #endif
943
944 return -EINVAL;
945 }
946
947 int is_valid_bugaddr(unsigned long addr)
948 {
949 return is_kernel_addr(addr);
950 }
951
952 void __kprobes program_check_exception(struct pt_regs *regs)
953 {
954 unsigned int reason = get_reason(regs);
955 extern int do_mathemu(struct pt_regs *regs);
956
957 /* We can now get here via a FP Unavailable exception if the core
958 * has no FPU, in that case the reason flags will be 0 */
959
960 if (reason & REASON_FP) {
961 /* IEEE FP exception */
962 parse_fpe(regs);
963 return;
964 }
965 if (reason & REASON_TRAP) {
966 /* Debugger is first in line to stop recursive faults in
967 * rcu_lock, notify_die, or atomic_notifier_call_chain */
968 if (debugger_bpt(regs))
969 return;
970
971 /* trap exception */
972 if (notify_die(DIE_BPT, "breakpoint", regs, 5, 5, SIGTRAP)
973 == NOTIFY_STOP)
974 return;
975
976 if (!(regs->msr & MSR_PR) && /* not user-mode */
977 report_bug(regs->nip, regs) == BUG_TRAP_TYPE_WARN) {
978 regs->nip += 4;
979 return;
980 }
981 _exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip);
982 return;
983 }
984
985 local_irq_enable();
986
987 #ifdef CONFIG_MATH_EMULATION
988 /* (reason & REASON_ILLEGAL) would be the obvious thing here,
989 * but there seems to be a hardware bug on the 405GP (RevD)
990 * that means ESR is sometimes set incorrectly - either to
991 * ESR_DST (!?) or 0. In the process of chasing this with the
992 * hardware people - not sure if it can happen on any illegal
993 * instruction or only on FP instructions, whether there is a
994 * pattern to occurrences etc. -dgibson 31/Mar/2003 */
995 switch (do_mathemu(regs)) {
996 case 0:
997 emulate_single_step(regs);
998 return;
999 case 1: {
1000 int code = 0;
1001 code = __parse_fpscr(current->thread.fpscr.val);
1002 _exception(SIGFPE, regs, code, regs->nip);
1003 return;
1004 }
1005 case -EFAULT:
1006 _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
1007 return;
1008 }
1009 /* fall through on any other errors */
1010 #endif /* CONFIG_MATH_EMULATION */
1011
1012 /* Try to emulate it if we should. */
1013 if (reason & (REASON_ILLEGAL | REASON_PRIVILEGED)) {
1014 switch (emulate_instruction(regs)) {
1015 case 0:
1016 regs->nip += 4;
1017 emulate_single_step(regs);
1018 return;
1019 case -EFAULT:
1020 _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
1021 return;
1022 }
1023 }
1024
1025 if (reason & REASON_PRIVILEGED)
1026 _exception(SIGILL, regs, ILL_PRVOPC, regs->nip);
1027 else
1028 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
1029 }
1030
1031 void alignment_exception(struct pt_regs *regs)
1032 {
1033 int sig, code, fixed = 0;
1034
1035 /* we don't implement logging of alignment exceptions */
1036 if (!(current->thread.align_ctl & PR_UNALIGN_SIGBUS))
1037 fixed = fix_alignment(regs);
1038
1039 if (fixed == 1) {
1040 regs->nip += 4; /* skip over emulated instruction */
1041 emulate_single_step(regs);
1042 return;
1043 }
1044
1045 /* Operand address was bad */
1046 if (fixed == -EFAULT) {
1047 sig = SIGSEGV;
1048 code = SEGV_ACCERR;
1049 } else {
1050 sig = SIGBUS;
1051 code = BUS_ADRALN;
1052 }
1053 if (user_mode(regs))
1054 _exception(sig, regs, code, regs->dar);
1055 else
1056 bad_page_fault(regs, regs->dar, sig);
1057 }
1058
1059 void StackOverflow(struct pt_regs *regs)
1060 {
1061 printk(KERN_CRIT "Kernel stack overflow in process %p, r1=%lx\n",
1062 current, regs->gpr[1]);
1063 debugger(regs);
1064 show_regs(regs);
1065 panic("kernel stack overflow");
1066 }
1067
1068 void nonrecoverable_exception(struct pt_regs *regs)
1069 {
1070 printk(KERN_ERR "Non-recoverable exception at PC=%lx MSR=%lx\n",
1071 regs->nip, regs->msr);
1072 debugger(regs);
1073 die("nonrecoverable exception", regs, SIGKILL);
1074 }
1075
1076 void trace_syscall(struct pt_regs *regs)
1077 {
1078 printk("Task: %p(%d), PC: %08lX/%08lX, Syscall: %3ld, Result: %s%ld %s\n",
1079 current, task_pid_nr(current), regs->nip, regs->link, regs->gpr[0],
1080 regs->ccr&0x10000000?"Error=":"", regs->gpr[3], print_tainted());
1081 }
1082
1083 void kernel_fp_unavailable_exception(struct pt_regs *regs)
1084 {
1085 printk(KERN_EMERG "Unrecoverable FP Unavailable Exception "
1086 "%lx at %lx\n", regs->trap, regs->nip);
1087 die("Unrecoverable FP Unavailable Exception", regs, SIGABRT);
1088 }
1089
1090 void altivec_unavailable_exception(struct pt_regs *regs)
1091 {
1092 if (user_mode(regs)) {
1093 /* A user program has executed an altivec instruction,
1094 but this kernel doesn't support altivec. */
1095 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
1096 return;
1097 }
1098
1099 printk(KERN_EMERG "Unrecoverable VMX/Altivec Unavailable Exception "
1100 "%lx at %lx\n", regs->trap, regs->nip);
1101 die("Unrecoverable VMX/Altivec Unavailable Exception", regs, SIGABRT);
1102 }
1103
1104 void vsx_unavailable_exception(struct pt_regs *regs)
1105 {
1106 if (user_mode(regs)) {
1107 /* A user program has executed an vsx instruction,
1108 but this kernel doesn't support vsx. */
1109 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
1110 return;
1111 }
1112
1113 printk(KERN_EMERG "Unrecoverable VSX Unavailable Exception "
1114 "%lx at %lx\n", regs->trap, regs->nip);
1115 die("Unrecoverable VSX Unavailable Exception", regs, SIGABRT);
1116 }
1117
1118 void performance_monitor_exception(struct pt_regs *regs)
1119 {
1120 __get_cpu_var(irq_stat).pmu_irqs++;
1121
1122 perf_irq(regs);
1123 }
1124
1125 #ifdef CONFIG_8xx
1126 void SoftwareEmulation(struct pt_regs *regs)
1127 {
1128 extern int do_mathemu(struct pt_regs *);
1129 extern int Soft_emulate_8xx(struct pt_regs *);
1130 #if defined(CONFIG_MATH_EMULATION) || defined(CONFIG_8XX_MINIMAL_FPEMU)
1131 int errcode;
1132 #endif
1133
1134 CHECK_FULL_REGS(regs);
1135
1136 if (!user_mode(regs)) {
1137 debugger(regs);
1138 die("Kernel Mode Software FPU Emulation", regs, SIGFPE);
1139 }
1140
1141 #ifdef CONFIG_MATH_EMULATION
1142 errcode = do_mathemu(regs);
1143 if (errcode >= 0)
1144 PPC_WARN_EMULATED(math, regs);
1145
1146 switch (errcode) {
1147 case 0:
1148 emulate_single_step(regs);
1149 return;
1150 case 1: {
1151 int code = 0;
1152 code = __parse_fpscr(current->thread.fpscr.val);
1153 _exception(SIGFPE, regs, code, regs->nip);
1154 return;
1155 }
1156 case -EFAULT:
1157 _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
1158 return;
1159 default:
1160 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
1161 return;
1162 }
1163
1164 #elif defined(CONFIG_8XX_MINIMAL_FPEMU)
1165 errcode = Soft_emulate_8xx(regs);
1166 if (errcode >= 0)
1167 PPC_WARN_EMULATED(8xx, regs);
1168
1169 switch (errcode) {
1170 case 0:
1171 emulate_single_step(regs);
1172 return;
1173 case 1:
1174 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
1175 return;
1176 case -EFAULT:
1177 _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
1178 return;
1179 }
1180 #else
1181 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
1182 #endif
1183 }
1184 #endif /* CONFIG_8xx */
1185
1186 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
1187 static void handle_debug(struct pt_regs *regs, unsigned long debug_status)
1188 {
1189 int changed = 0;
1190 /*
1191 * Determine the cause of the debug event, clear the
1192 * event flags and send a trap to the handler. Torez
1193 */
1194 if (debug_status & (DBSR_DAC1R | DBSR_DAC1W)) {
1195 dbcr_dac(current) &= ~(DBCR_DAC1R | DBCR_DAC1W);
1196 #ifdef CONFIG_PPC_ADV_DEBUG_DAC_RANGE
1197 current->thread.dbcr2 &= ~DBCR2_DAC12MODE;
1198 #endif
1199 do_send_trap(regs, mfspr(SPRN_DAC1), debug_status, TRAP_HWBKPT,
1200 5);
1201 changed |= 0x01;
1202 } else if (debug_status & (DBSR_DAC2R | DBSR_DAC2W)) {
1203 dbcr_dac(current) &= ~(DBCR_DAC2R | DBCR_DAC2W);
1204 do_send_trap(regs, mfspr(SPRN_DAC2), debug_status, TRAP_HWBKPT,
1205 6);
1206 changed |= 0x01;
1207 } else if (debug_status & DBSR_IAC1) {
1208 current->thread.dbcr0 &= ~DBCR0_IAC1;
1209 dbcr_iac_range(current) &= ~DBCR_IAC12MODE;
1210 do_send_trap(regs, mfspr(SPRN_IAC1), debug_status, TRAP_HWBKPT,
1211 1);
1212 changed |= 0x01;
1213 } else if (debug_status & DBSR_IAC2) {
1214 current->thread.dbcr0 &= ~DBCR0_IAC2;
1215 do_send_trap(regs, mfspr(SPRN_IAC2), debug_status, TRAP_HWBKPT,
1216 2);
1217 changed |= 0x01;
1218 } else if (debug_status & DBSR_IAC3) {
1219 current->thread.dbcr0 &= ~DBCR0_IAC3;
1220 dbcr_iac_range(current) &= ~DBCR_IAC34MODE;
1221 do_send_trap(regs, mfspr(SPRN_IAC3), debug_status, TRAP_HWBKPT,
1222 3);
1223 changed |= 0x01;
1224 } else if (debug_status & DBSR_IAC4) {
1225 current->thread.dbcr0 &= ~DBCR0_IAC4;
1226 do_send_trap(regs, mfspr(SPRN_IAC4), debug_status, TRAP_HWBKPT,
1227 4);
1228 changed |= 0x01;
1229 }
1230 /*
1231 * At the point this routine was called, the MSR(DE) was turned off.
1232 * Check all other debug flags and see if that bit needs to be turned
1233 * back on or not.
1234 */
1235 if (DBCR_ACTIVE_EVENTS(current->thread.dbcr0, current->thread.dbcr1))
1236 regs->msr |= MSR_DE;
1237 else
1238 /* Make sure the IDM flag is off */
1239 current->thread.dbcr0 &= ~DBCR0_IDM;
1240
1241 if (changed & 0x01)
1242 mtspr(SPRN_DBCR0, current->thread.dbcr0);
1243 }
1244
1245 void __kprobes DebugException(struct pt_regs *regs, unsigned long debug_status)
1246 {
1247 current->thread.dbsr = debug_status;
1248
1249 /* Hack alert: On BookE, Branch Taken stops on the branch itself, while
1250 * on server, it stops on the target of the branch. In order to simulate
1251 * the server behaviour, we thus restart right away with a single step
1252 * instead of stopping here when hitting a BT
1253 */
1254 if (debug_status & DBSR_BT) {
1255 regs->msr &= ~MSR_DE;
1256
1257 /* Disable BT */
1258 mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) & ~DBCR0_BT);
1259 /* Clear the BT event */
1260 mtspr(SPRN_DBSR, DBSR_BT);
1261
1262 /* Do the single step trick only when coming from userspace */
1263 if (user_mode(regs)) {
1264 current->thread.dbcr0 &= ~DBCR0_BT;
1265 current->thread.dbcr0 |= DBCR0_IDM | DBCR0_IC;
1266 regs->msr |= MSR_DE;
1267 return;
1268 }
1269
1270 if (notify_die(DIE_SSTEP, "block_step", regs, 5,
1271 5, SIGTRAP) == NOTIFY_STOP) {
1272 return;
1273 }
1274 if (debugger_sstep(regs))
1275 return;
1276 } else if (debug_status & DBSR_IC) { /* Instruction complete */
1277 regs->msr &= ~MSR_DE;
1278
1279 /* Disable instruction completion */
1280 mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) & ~DBCR0_IC);
1281 /* Clear the instruction completion event */
1282 mtspr(SPRN_DBSR, DBSR_IC);
1283
1284 if (notify_die(DIE_SSTEP, "single_step", regs, 5,
1285 5, SIGTRAP) == NOTIFY_STOP) {
1286 return;
1287 }
1288
1289 if (debugger_sstep(regs))
1290 return;
1291
1292 if (user_mode(regs)) {
1293 current->thread.dbcr0 &= ~DBCR0_IC;
1294 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
1295 if (DBCR_ACTIVE_EVENTS(current->thread.dbcr0,
1296 current->thread.dbcr1))
1297 regs->msr |= MSR_DE;
1298 else
1299 /* Make sure the IDM bit is off */
1300 current->thread.dbcr0 &= ~DBCR0_IDM;
1301 #endif
1302 }
1303
1304 _exception(SIGTRAP, regs, TRAP_TRACE, regs->nip);
1305 } else
1306 handle_debug(regs, debug_status);
1307 }
1308 #endif /* CONFIG_PPC_ADV_DEBUG_REGS */
1309
1310 #if !defined(CONFIG_TAU_INT)
1311 void TAUException(struct pt_regs *regs)
1312 {
1313 printk("TAU trap at PC: %lx, MSR: %lx, vector=%lx %s\n",
1314 regs->nip, regs->msr, regs->trap, print_tainted());
1315 }
1316 #endif /* CONFIG_INT_TAU */
1317
1318 #ifdef CONFIG_ALTIVEC
1319 void altivec_assist_exception(struct pt_regs *regs)
1320 {
1321 int err;
1322
1323 if (!user_mode(regs)) {
1324 printk(KERN_EMERG "VMX/Altivec assist exception in kernel mode"
1325 " at %lx\n", regs->nip);
1326 die("Kernel VMX/Altivec assist exception", regs, SIGILL);
1327 }
1328
1329 flush_altivec_to_thread(current);
1330
1331 PPC_WARN_EMULATED(altivec, regs);
1332 err = emulate_altivec(regs);
1333 if (err == 0) {
1334 regs->nip += 4; /* skip emulated instruction */
1335 emulate_single_step(regs);
1336 return;
1337 }
1338
1339 if (err == -EFAULT) {
1340 /* got an error reading the instruction */
1341 _exception(SIGSEGV, regs, SEGV_ACCERR, regs->nip);
1342 } else {
1343 /* didn't recognize the instruction */
1344 /* XXX quick hack for now: set the non-Java bit in the VSCR */
1345 printk_ratelimited(KERN_ERR "Unrecognized altivec instruction "
1346 "in %s at %lx\n", current->comm, regs->nip);
1347 current->thread.vscr.u[3] |= 0x10000;
1348 }
1349 }
1350 #endif /* CONFIG_ALTIVEC */
1351
1352 #ifdef CONFIG_VSX
1353 void vsx_assist_exception(struct pt_regs *regs)
1354 {
1355 if (!user_mode(regs)) {
1356 printk(KERN_EMERG "VSX assist exception in kernel mode"
1357 " at %lx\n", regs->nip);
1358 die("Kernel VSX assist exception", regs, SIGILL);
1359 }
1360
1361 flush_vsx_to_thread(current);
1362 printk(KERN_INFO "VSX assist not supported at %lx\n", regs->nip);
1363 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
1364 }
1365 #endif /* CONFIG_VSX */
1366
1367 #ifdef CONFIG_FSL_BOOKE
1368 void CacheLockingException(struct pt_regs *regs, unsigned long address,
1369 unsigned long error_code)
1370 {
1371 /* We treat cache locking instructions from the user
1372 * as priv ops, in the future we could try to do
1373 * something smarter
1374 */
1375 if (error_code & (ESR_DLK|ESR_ILK))
1376 _exception(SIGILL, regs, ILL_PRVOPC, regs->nip);
1377 return;
1378 }
1379 #endif /* CONFIG_FSL_BOOKE */
1380
1381 #ifdef CONFIG_SPE
1382 void SPEFloatingPointException(struct pt_regs *regs)
1383 {
1384 extern int do_spe_mathemu(struct pt_regs *regs);
1385 unsigned long spefscr;
1386 int fpexc_mode;
1387 int code = 0;
1388 int err;
1389
1390 flush_spe_to_thread(current);
1391
1392 spefscr = current->thread.spefscr;
1393 fpexc_mode = current->thread.fpexc_mode;
1394
1395 if ((spefscr & SPEFSCR_FOVF) && (fpexc_mode & PR_FP_EXC_OVF)) {
1396 code = FPE_FLTOVF;
1397 }
1398 else if ((spefscr & SPEFSCR_FUNF) && (fpexc_mode & PR_FP_EXC_UND)) {
1399 code = FPE_FLTUND;
1400 }
1401 else if ((spefscr & SPEFSCR_FDBZ) && (fpexc_mode & PR_FP_EXC_DIV))
1402 code = FPE_FLTDIV;
1403 else if ((spefscr & SPEFSCR_FINV) && (fpexc_mode & PR_FP_EXC_INV)) {
1404 code = FPE_FLTINV;
1405 }
1406 else if ((spefscr & (SPEFSCR_FG | SPEFSCR_FX)) && (fpexc_mode & PR_FP_EXC_RES))
1407 code = FPE_FLTRES;
1408
1409 err = do_spe_mathemu(regs);
1410 if (err == 0) {
1411 regs->nip += 4; /* skip emulated instruction */
1412 emulate_single_step(regs);
1413 return;
1414 }
1415
1416 if (err == -EFAULT) {
1417 /* got an error reading the instruction */
1418 _exception(SIGSEGV, regs, SEGV_ACCERR, regs->nip);
1419 } else if (err == -EINVAL) {
1420 /* didn't recognize the instruction */
1421 printk(KERN_ERR "unrecognized spe instruction "
1422 "in %s at %lx\n", current->comm, regs->nip);
1423 } else {
1424 _exception(SIGFPE, regs, code, regs->nip);
1425 }
1426
1427 return;
1428 }
1429
1430 void SPEFloatingPointRoundException(struct pt_regs *regs)
1431 {
1432 extern int speround_handler(struct pt_regs *regs);
1433 int err;
1434
1435 preempt_disable();
1436 if (regs->msr & MSR_SPE)
1437 giveup_spe(current);
1438 preempt_enable();
1439
1440 regs->nip -= 4;
1441 err = speround_handler(regs);
1442 if (err == 0) {
1443 regs->nip += 4; /* skip emulated instruction */
1444 emulate_single_step(regs);
1445 return;
1446 }
1447
1448 if (err == -EFAULT) {
1449 /* got an error reading the instruction */
1450 _exception(SIGSEGV, regs, SEGV_ACCERR, regs->nip);
1451 } else if (err == -EINVAL) {
1452 /* didn't recognize the instruction */
1453 printk(KERN_ERR "unrecognized spe instruction "
1454 "in %s at %lx\n", current->comm, regs->nip);
1455 } else {
1456 _exception(SIGFPE, regs, 0, regs->nip);
1457 return;
1458 }
1459 }
1460 #endif
1461
1462 /*
1463 * We enter here if we get an unrecoverable exception, that is, one
1464 * that happened at a point where the RI (recoverable interrupt) bit
1465 * in the MSR is 0. This indicates that SRR0/1 are live, and that
1466 * we therefore lost state by taking this exception.
1467 */
1468 void unrecoverable_exception(struct pt_regs *regs)
1469 {
1470 printk(KERN_EMERG "Unrecoverable exception %lx at %lx\n",
1471 regs->trap, regs->nip);
1472 die("Unrecoverable exception", regs, SIGABRT);
1473 }
1474
1475 #ifdef CONFIG_BOOKE_WDT
1476 /*
1477 * Default handler for a Watchdog exception,
1478 * spins until a reboot occurs
1479 */
1480 void __attribute__ ((weak)) WatchdogHandler(struct pt_regs *regs)
1481 {
1482 /* Generic WatchdogHandler, implement your own */
1483 mtspr(SPRN_TCR, mfspr(SPRN_TCR)&(~TCR_WIE));
1484 return;
1485 }
1486
1487 void WatchdogException(struct pt_regs *regs)
1488 {
1489 printk (KERN_EMERG "PowerPC Book-E Watchdog Exception\n");
1490 WatchdogHandler(regs);
1491 }
1492 #endif
1493
1494 /*
1495 * We enter here if we discover during exception entry that we are
1496 * running in supervisor mode with a userspace value in the stack pointer.
1497 */
1498 void kernel_bad_stack(struct pt_regs *regs)
1499 {
1500 printk(KERN_EMERG "Bad kernel stack pointer %lx at %lx\n",
1501 regs->gpr[1], regs->nip);
1502 die("Bad kernel stack pointer", regs, SIGABRT);
1503 }
1504
1505 void __init trap_init(void)
1506 {
1507 }
1508
1509
1510 #ifdef CONFIG_PPC_EMULATED_STATS
1511
1512 #define WARN_EMULATED_SETUP(type) .type = { .name = #type }
1513
1514 struct ppc_emulated ppc_emulated = {
1515 #ifdef CONFIG_ALTIVEC
1516 WARN_EMULATED_SETUP(altivec),
1517 #endif
1518 WARN_EMULATED_SETUP(dcba),
1519 WARN_EMULATED_SETUP(dcbz),
1520 WARN_EMULATED_SETUP(fp_pair),
1521 WARN_EMULATED_SETUP(isel),
1522 WARN_EMULATED_SETUP(mcrxr),
1523 WARN_EMULATED_SETUP(mfpvr),
1524 WARN_EMULATED_SETUP(multiple),
1525 WARN_EMULATED_SETUP(popcntb),
1526 WARN_EMULATED_SETUP(spe),
1527 WARN_EMULATED_SETUP(string),
1528 WARN_EMULATED_SETUP(unaligned),
1529 #ifdef CONFIG_MATH_EMULATION
1530 WARN_EMULATED_SETUP(math),
1531 #elif defined(CONFIG_8XX_MINIMAL_FPEMU)
1532 WARN_EMULATED_SETUP(8xx),
1533 #endif
1534 #ifdef CONFIG_VSX
1535 WARN_EMULATED_SETUP(vsx),
1536 #endif
1537 #ifdef CONFIG_PPC64
1538 WARN_EMULATED_SETUP(mfdscr),
1539 WARN_EMULATED_SETUP(mtdscr),
1540 #endif
1541 };
1542
1543 u32 ppc_warn_emulated;
1544
1545 void ppc_warn_emulated_print(const char *type)
1546 {
1547 pr_warn_ratelimited("%s used emulated %s instruction\n", current->comm,
1548 type);
1549 }
1550
1551 static int __init ppc_warn_emulated_init(void)
1552 {
1553 struct dentry *dir, *d;
1554 unsigned int i;
1555 struct ppc_emulated_entry *entries = (void *)&ppc_emulated;
1556
1557 if (!powerpc_debugfs_root)
1558 return -ENODEV;
1559
1560 dir = debugfs_create_dir("emulated_instructions",
1561 powerpc_debugfs_root);
1562 if (!dir)
1563 return -ENOMEM;
1564
1565 d = debugfs_create_u32("do_warn", S_IRUGO | S_IWUSR, dir,
1566 &ppc_warn_emulated);
1567 if (!d)
1568 goto fail;
1569
1570 for (i = 0; i < sizeof(ppc_emulated)/sizeof(*entries); i++) {
1571 d = debugfs_create_u32(entries[i].name, S_IRUGO | S_IWUSR, dir,
1572 (u32 *)&entries[i].val.counter);
1573 if (!d)
1574 goto fail;
1575 }
1576
1577 return 0;
1578
1579 fail:
1580 debugfs_remove_recursive(dir);
1581 return -ENOMEM;
1582 }
1583
1584 device_initcall(ppc_warn_emulated_init);
1585
1586 #endif /* CONFIG_PPC_EMULATED_STATS */
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