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