2 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
9 * Modified by Cort Dougan (cort@cs.nmt.edu)
10 * and Paul Mackerras (paulus@samba.org)
14 * This file handles the architecture-dependent parts of hardware exceptions
17 #include <linux/config.h>
18 #include <linux/errno.h>
19 #include <linux/sched.h>
20 #include <linux/kernel.h>
22 #include <linux/stddef.h>
23 #include <linux/unistd.h>
24 #include <linux/ptrace.h>
25 #include <linux/slab.h>
26 #include <linux/user.h>
27 #include <linux/a.out.h>
28 #include <linux/interrupt.h>
29 #include <linux/init.h>
30 #include <linux/module.h>
31 #include <linux/prctl.h>
32 #include <linux/delay.h>
33 #include <linux/kprobes.h>
34 #include <linux/kexec.h>
36 #include <asm/kdebug.h>
37 #include <asm/pgtable.h>
38 #include <asm/uaccess.h>
39 #include <asm/system.h>
41 #include <asm/machdep.h>
47 #ifdef CONFIG_PMAC_BACKLIGHT
48 #include <asm/backlight.h>
51 #include <asm/firmware.h>
52 #include <asm/processor.h>
55 #ifdef CONFIG_PPC64 /* XXX */
56 #define _IO_BASE pci_io_base
59 #ifdef CONFIG_DEBUGGER
60 int (*__debugger)(struct pt_regs *regs);
61 int (*__debugger_ipi)(struct pt_regs *regs);
62 int (*__debugger_bpt)(struct pt_regs *regs);
63 int (*__debugger_sstep)(struct pt_regs *regs);
64 int (*__debugger_iabr_match)(struct pt_regs *regs);
65 int (*__debugger_dabr_match)(struct pt_regs *regs);
66 int (*__debugger_fault_handler)(struct pt_regs *regs);
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);
77 ATOMIC_NOTIFIER_HEAD(powerpc_die_chain);
79 int register_die_notifier(struct notifier_block *nb)
81 return atomic_notifier_chain_register(&powerpc_die_chain, nb);
83 EXPORT_SYMBOL(register_die_notifier);
85 int unregister_die_notifier(struct notifier_block *nb)
87 return atomic_notifier_chain_unregister(&powerpc_die_chain, nb);
89 EXPORT_SYMBOL(unregister_die_notifier);
92 * Trap & Exception support
95 static DEFINE_SPINLOCK(die_lock);
97 int die(const char *str, struct pt_regs *regs, long err)
99 static int die_counter, crash_dump_start = 0;
105 spin_lock_irq(&die_lock);
107 #ifdef CONFIG_PMAC_BACKLIGHT
108 if (machine_is(powermac)) {
109 set_backlight_enable(1);
110 set_backlight_level(BACKLIGHT_MAX);
113 printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
114 #ifdef CONFIG_PREEMPT
118 printk("SMP NR_CPUS=%d ", NR_CPUS);
120 #ifdef CONFIG_DEBUG_PAGEALLOC
121 printk("DEBUG_PAGEALLOC ");
126 printk("%s\n", ppc_md.name ? "" : ppc_md.name);
132 if (!crash_dump_start && kexec_should_crash(current)) {
133 crash_dump_start = 1;
134 spin_unlock_irq(&die_lock);
138 spin_unlock_irq(&die_lock);
139 if (crash_dump_start)
141 * Only for soft-reset: Other CPUs will be responded to an IPI
142 * sent by first kexec CPU.
148 panic("Fatal exception in interrupt");
152 printk(KERN_EMERG "Fatal exception: panic in 5 seconds\n");
155 panic("Fatal exception");
162 void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
166 if (!user_mode(regs)) {
167 if (die("Exception in kernel mode", regs, signr))
171 memset(&info, 0, sizeof(info));
172 info.si_signo = signr;
174 info.si_addr = (void __user *) addr;
175 force_sig_info(signr, &info, current);
178 * Init gets no signals that it doesn't have a handler for.
179 * That's all very well, but if it has caused a synchronous
180 * exception and we ignore the resulting signal, it will just
181 * generate the same exception over and over again and we get
182 * nowhere. Better to kill it and let the kernel panic.
184 if (current->pid == 1) {
185 __sighandler_t handler;
187 spin_lock_irq(¤t->sighand->siglock);
188 handler = current->sighand->action[signr-1].sa.sa_handler;
189 spin_unlock_irq(¤t->sighand->siglock);
190 if (handler == SIG_DFL) {
191 /* init has generated a synchronous exception
192 and it doesn't have a handler for the signal */
193 printk(KERN_CRIT "init has generated signal %d "
194 "but has no handler for it\n", signr);
201 void system_reset_exception(struct pt_regs *regs)
203 /* See if any machine dependent calls */
204 if (ppc_md.system_reset_exception) {
205 if (ppc_md.system_reset_exception(regs))
209 die("System Reset", regs, SIGABRT);
211 /* Must die if the interrupt is not recoverable */
212 if (!(regs->msr & MSR_RI))
213 panic("Unrecoverable System Reset");
215 /* What should we do here? We could issue a shutdown or hard reset. */
220 * I/O accesses can cause machine checks on powermacs.
221 * Check if the NIP corresponds to the address of a sync
222 * instruction for which there is an entry in the exception
224 * Note that the 601 only takes a machine check on TEA
225 * (transfer error ack) signal assertion, and does not
226 * set any of the top 16 bits of SRR1.
229 static inline int check_io_access(struct pt_regs *regs)
231 #ifdef CONFIG_PPC_PMAC
232 unsigned long msr = regs->msr;
233 const struct exception_table_entry *entry;
234 unsigned int *nip = (unsigned int *)regs->nip;
236 if (((msr & 0xffff0000) == 0 || (msr & (0x80000 | 0x40000)))
237 && (entry = search_exception_tables(regs->nip)) != NULL) {
239 * Check that it's a sync instruction, or somewhere
240 * in the twi; isync; nop sequence that inb/inw/inl uses.
241 * As the address is in the exception table
242 * we should be able to read the instr there.
243 * For the debug message, we look at the preceding
246 if (*nip == 0x60000000) /* nop */
248 else if (*nip == 0x4c00012c) /* isync */
250 if (*nip == 0x7c0004ac || (*nip >> 26) == 3) {
255 rb = (*nip >> 11) & 0x1f;
256 printk(KERN_DEBUG "%s bad port %lx at %p\n",
257 (*nip & 0x100)? "OUT to": "IN from",
258 regs->gpr[rb] - _IO_BASE, nip);
260 regs->nip = entry->fixup;
264 #endif /* CONFIG_PPC_PMAC */
268 #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
269 /* On 4xx, the reason for the machine check or program exception
271 #define get_reason(regs) ((regs)->dsisr)
272 #ifndef CONFIG_FSL_BOOKE
273 #define get_mc_reason(regs) ((regs)->dsisr)
275 #define get_mc_reason(regs) (mfspr(SPRN_MCSR))
277 #define REASON_FP ESR_FP
278 #define REASON_ILLEGAL (ESR_PIL | ESR_PUO)
279 #define REASON_PRIVILEGED ESR_PPR
280 #define REASON_TRAP ESR_PTR
282 /* single-step stuff */
283 #define single_stepping(regs) (current->thread.dbcr0 & DBCR0_IC)
284 #define clear_single_step(regs) (current->thread.dbcr0 &= ~DBCR0_IC)
287 /* On non-4xx, the reason for the machine check or program
288 exception is in the MSR. */
289 #define get_reason(regs) ((regs)->msr)
290 #define get_mc_reason(regs) ((regs)->msr)
291 #define REASON_FP 0x100000
292 #define REASON_ILLEGAL 0x80000
293 #define REASON_PRIVILEGED 0x40000
294 #define REASON_TRAP 0x20000
296 #define single_stepping(regs) ((regs)->msr & MSR_SE)
297 #define clear_single_step(regs) ((regs)->msr &= ~MSR_SE)
301 * This is "fall-back" implementation for configurations
302 * which don't provide platform-specific machine check info
304 void __attribute__ ((weak))
305 platform_machine_check(struct pt_regs *regs)
309 void machine_check_exception(struct pt_regs *regs)
314 /* See if any machine dependent calls */
315 if (ppc_md.machine_check_exception)
316 recover = ppc_md.machine_check_exception(regs);
321 unsigned long reason = get_mc_reason(regs);
323 if (user_mode(regs)) {
325 _exception(SIGBUS, regs, BUS_ADRERR, regs->nip);
329 #if defined(CONFIG_8xx) && defined(CONFIG_PCI)
330 /* the qspan pci read routines can cause machine checks -- Cort */
331 bad_page_fault(regs, regs->dar, SIGBUS);
335 if (debugger_fault_handler(regs)) {
340 if (check_io_access(regs))
343 #if defined(CONFIG_4xx) && !defined(CONFIG_440A)
344 if (reason & ESR_IMCP) {
345 printk("Instruction");
346 mtspr(SPRN_ESR, reason & ~ESR_IMCP);
349 printk(" machine check in kernel mode.\n");
350 #elif defined(CONFIG_440A)
351 printk("Machine check in kernel mode.\n");
352 if (reason & ESR_IMCP){
353 printk("Instruction Synchronous Machine Check exception\n");
354 mtspr(SPRN_ESR, reason & ~ESR_IMCP);
357 u32 mcsr = mfspr(SPRN_MCSR);
359 printk("Instruction Read PLB Error\n");
361 printk("Data Read PLB Error\n");
363 printk("Data Write PLB Error\n");
364 if (mcsr & MCSR_TLBP)
365 printk("TLB Parity Error\n");
366 if (mcsr & MCSR_ICP){
367 flush_instruction_cache();
368 printk("I-Cache Parity Error\n");
370 if (mcsr & MCSR_DCSP)
371 printk("D-Cache Search Parity Error\n");
372 if (mcsr & MCSR_DCFP)
373 printk("D-Cache Flush Parity Error\n");
374 if (mcsr & MCSR_IMPE)
375 printk("Machine Check exception is imprecise\n");
378 mtspr(SPRN_MCSR, mcsr);
380 #elif defined (CONFIG_E500)
381 printk("Machine check in kernel mode.\n");
382 printk("Caused by (from MCSR=%lx): ", reason);
384 if (reason & MCSR_MCP)
385 printk("Machine Check Signal\n");
386 if (reason & MCSR_ICPERR)
387 printk("Instruction Cache Parity Error\n");
388 if (reason & MCSR_DCP_PERR)
389 printk("Data Cache Push Parity Error\n");
390 if (reason & MCSR_DCPERR)
391 printk("Data Cache Parity Error\n");
392 if (reason & MCSR_GL_CI)
393 printk("Guarded Load or Cache-Inhibited stwcx.\n");
394 if (reason & MCSR_BUS_IAERR)
395 printk("Bus - Instruction Address Error\n");
396 if (reason & MCSR_BUS_RAERR)
397 printk("Bus - Read Address Error\n");
398 if (reason & MCSR_BUS_WAERR)
399 printk("Bus - Write Address Error\n");
400 if (reason & MCSR_BUS_IBERR)
401 printk("Bus - Instruction Data Error\n");
402 if (reason & MCSR_BUS_RBERR)
403 printk("Bus - Read Data Bus Error\n");
404 if (reason & MCSR_BUS_WBERR)
405 printk("Bus - Read Data Bus Error\n");
406 if (reason & MCSR_BUS_IPERR)
407 printk("Bus - Instruction Parity Error\n");
408 if (reason & MCSR_BUS_RPERR)
409 printk("Bus - Read Parity Error\n");
410 #elif defined (CONFIG_E200)
411 printk("Machine check in kernel mode.\n");
412 printk("Caused by (from MCSR=%lx): ", reason);
414 if (reason & MCSR_MCP)
415 printk("Machine Check Signal\n");
416 if (reason & MCSR_CP_PERR)
417 printk("Cache Push Parity Error\n");
418 if (reason & MCSR_CPERR)
419 printk("Cache Parity Error\n");
420 if (reason & MCSR_EXCP_ERR)
421 printk("ISI, ITLB, or Bus Error on first instruction fetch for an exception handler\n");
422 if (reason & MCSR_BUS_IRERR)
423 printk("Bus - Read Bus Error on instruction fetch\n");
424 if (reason & MCSR_BUS_DRERR)
425 printk("Bus - Read Bus Error on data load\n");
426 if (reason & MCSR_BUS_WRERR)
427 printk("Bus - Write Bus Error on buffered store or cache line push\n");
428 #else /* !CONFIG_4xx && !CONFIG_E500 && !CONFIG_E200 */
429 printk("Machine check in kernel mode.\n");
430 printk("Caused by (from SRR1=%lx): ", reason);
431 switch (reason & 0x601F0000) {
433 printk("Machine check signal\n");
435 case 0: /* for 601 */
437 case 0x140000: /* 7450 MSS error and TEA */
438 printk("Transfer error ack signal\n");
441 printk("Data parity error signal\n");
444 printk("Address parity error signal\n");
447 printk("L1 Data Cache error\n");
450 printk("L1 Instruction Cache error\n");
453 printk("L2 data cache parity error\n");
456 printk("Unknown values in msr\n");
458 #endif /* CONFIG_4xx */
461 * Optional platform-provided routine to print out
462 * additional info, e.g. bus error registers.
464 platform_machine_check(regs);
465 #endif /* CONFIG_PPC64 */
467 if (debugger_fault_handler(regs))
469 die("Machine check", regs, SIGBUS);
471 /* Must die if the interrupt is not recoverable */
472 if (!(regs->msr & MSR_RI))
473 panic("Unrecoverable Machine check");
476 void SMIException(struct pt_regs *regs)
478 die("System Management Interrupt", regs, SIGABRT);
481 void unknown_exception(struct pt_regs *regs)
483 printk("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
484 regs->nip, regs->msr, regs->trap);
486 _exception(SIGTRAP, regs, 0, 0);
489 void instruction_breakpoint_exception(struct pt_regs *regs)
491 if (notify_die(DIE_IABR_MATCH, "iabr_match", regs, 5,
492 5, SIGTRAP) == NOTIFY_STOP)
494 if (debugger_iabr_match(regs))
496 _exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip);
499 void RunModeException(struct pt_regs *regs)
501 _exception(SIGTRAP, regs, 0, 0);
504 void __kprobes single_step_exception(struct pt_regs *regs)
506 regs->msr &= ~(MSR_SE | MSR_BE); /* Turn off 'trace' bits */
508 if (notify_die(DIE_SSTEP, "single_step", regs, 5,
509 5, SIGTRAP) == NOTIFY_STOP)
511 if (debugger_sstep(regs))
514 _exception(SIGTRAP, regs, TRAP_TRACE, regs->nip);
518 * After we have successfully emulated an instruction, we have to
519 * check if the instruction was being single-stepped, and if so,
520 * pretend we got a single-step exception. This was pointed out
521 * by Kumar Gala. -- paulus
523 static void emulate_single_step(struct pt_regs *regs)
525 if (single_stepping(regs)) {
526 clear_single_step(regs);
527 _exception(SIGTRAP, regs, TRAP_TRACE, 0);
531 static void parse_fpe(struct pt_regs *regs)
536 flush_fp_to_thread(current);
538 fpscr = current->thread.fpscr.val;
540 /* Invalid operation */
541 if ((fpscr & FPSCR_VE) && (fpscr & FPSCR_VX))
545 else if ((fpscr & FPSCR_OE) && (fpscr & FPSCR_OX))
549 else if ((fpscr & FPSCR_UE) && (fpscr & FPSCR_UX))
553 else if ((fpscr & FPSCR_ZE) && (fpscr & FPSCR_ZX))
557 else if ((fpscr & FPSCR_XE) && (fpscr & FPSCR_XX))
560 _exception(SIGFPE, regs, code, regs->nip);
564 * Illegal instruction emulation support. Originally written to
565 * provide the PVR to user applications using the mfspr rd, PVR.
566 * Return non-zero if we can't emulate, or -EFAULT if the associated
567 * memory access caused an access fault. Return zero on success.
569 * There are a couple of ways to do this, either "decode" the instruction
570 * or directly match lots of bits. In this case, matching lots of
571 * bits is faster and easier.
574 #define INST_MFSPR_PVR 0x7c1f42a6
575 #define INST_MFSPR_PVR_MASK 0xfc1fffff
577 #define INST_DCBA 0x7c0005ec
578 #define INST_DCBA_MASK 0x7c0007fe
580 #define INST_MCRXR 0x7c000400
581 #define INST_MCRXR_MASK 0x7c0007fe
583 #define INST_STRING 0x7c00042a
584 #define INST_STRING_MASK 0x7c0007fe
585 #define INST_STRING_GEN_MASK 0x7c00067e
586 #define INST_LSWI 0x7c0004aa
587 #define INST_LSWX 0x7c00042a
588 #define INST_STSWI 0x7c0005aa
589 #define INST_STSWX 0x7c00052a
591 static int emulate_string_inst(struct pt_regs *regs, u32 instword)
593 u8 rT = (instword >> 21) & 0x1f;
594 u8 rA = (instword >> 16) & 0x1f;
595 u8 NB_RB = (instword >> 11) & 0x1f;
600 /* Early out if we are an invalid form of lswx */
601 if ((instword & INST_STRING_MASK) == INST_LSWX)
602 if ((rT == rA) || (rT == NB_RB))
605 EA = (rA == 0) ? 0 : regs->gpr[rA];
607 switch (instword & INST_STRING_MASK) {
611 num_bytes = regs->xer & 0x7f;
615 num_bytes = (NB_RB == 0) ? 32 : NB_RB;
621 while (num_bytes != 0)
624 u32 shift = 8 * (3 - (pos & 0x3));
626 switch ((instword & INST_STRING_MASK)) {
629 if (get_user(val, (u8 __user *)EA))
631 /* first time updating this reg,
635 regs->gpr[rT] |= val << shift;
639 val = regs->gpr[rT] >> shift;
640 if (put_user(val, (u8 __user *)EA))
644 /* move EA to next address */
648 /* manage our position within the register */
659 static int emulate_instruction(struct pt_regs *regs)
664 if (!user_mode(regs))
666 CHECK_FULL_REGS(regs);
668 if (get_user(instword, (u32 __user *)(regs->nip)))
671 /* Emulate the mfspr rD, PVR. */
672 if ((instword & INST_MFSPR_PVR_MASK) == INST_MFSPR_PVR) {
673 rd = (instword >> 21) & 0x1f;
674 regs->gpr[rd] = mfspr(SPRN_PVR);
678 /* Emulating the dcba insn is just a no-op. */
679 if ((instword & INST_DCBA_MASK) == INST_DCBA)
682 /* Emulate the mcrxr insn. */
683 if ((instword & INST_MCRXR_MASK) == INST_MCRXR) {
684 int shift = (instword >> 21) & 0x1c;
685 unsigned long msk = 0xf0000000UL >> shift;
687 regs->ccr = (regs->ccr & ~msk) | ((regs->xer >> shift) & msk);
688 regs->xer &= ~0xf0000000UL;
692 /* Emulate load/store string insn. */
693 if ((instword & INST_STRING_GEN_MASK) == INST_STRING)
694 return emulate_string_inst(regs, instword);
700 * Look through the list of trap instructions that are used for BUG(),
701 * BUG_ON() and WARN_ON() and see if we hit one. At this point we know
702 * that the exception was caused by a trap instruction of some kind.
703 * Returns 1 if we should continue (i.e. it was a WARN_ON) or 0
706 extern struct bug_entry __start___bug_table[], __stop___bug_table[];
708 #ifndef CONFIG_MODULES
709 #define module_find_bug(x) NULL
712 struct bug_entry *find_bug(unsigned long bugaddr)
714 struct bug_entry *bug;
716 for (bug = __start___bug_table; bug < __stop___bug_table; ++bug)
717 if (bugaddr == bug->bug_addr)
719 return module_find_bug(bugaddr);
722 static int check_bug_trap(struct pt_regs *regs)
724 struct bug_entry *bug;
727 if (regs->msr & MSR_PR)
728 return 0; /* not in kernel */
729 addr = regs->nip; /* address of trap instruction */
730 if (addr < PAGE_OFFSET)
732 bug = find_bug(regs->nip);
735 if (bug->line & BUG_WARNING_TRAP) {
736 /* this is a WARN_ON rather than BUG/BUG_ON */
737 printk(KERN_ERR "Badness in %s at %s:%ld\n",
738 bug->function, bug->file,
739 bug->line & ~BUG_WARNING_TRAP);
743 printk(KERN_CRIT "kernel BUG in %s at %s:%ld!\n",
744 bug->function, bug->file, bug->line);
749 void __kprobes program_check_exception(struct pt_regs *regs)
751 unsigned int reason = get_reason(regs);
752 extern int do_mathemu(struct pt_regs *regs);
754 #ifdef CONFIG_MATH_EMULATION
755 /* (reason & REASON_ILLEGAL) would be the obvious thing here,
756 * but there seems to be a hardware bug on the 405GP (RevD)
757 * that means ESR is sometimes set incorrectly - either to
758 * ESR_DST (!?) or 0. In the process of chasing this with the
759 * hardware people - not sure if it can happen on any illegal
760 * instruction or only on FP instructions, whether there is a
761 * pattern to occurences etc. -dgibson 31/Mar/2003 */
762 if (!(reason & REASON_TRAP) && do_mathemu(regs) == 0) {
763 emulate_single_step(regs);
766 #endif /* CONFIG_MATH_EMULATION */
768 if (reason & REASON_FP) {
769 /* IEEE FP exception */
773 if (reason & REASON_TRAP) {
775 if (notify_die(DIE_BPT, "breakpoint", regs, 5, 5, SIGTRAP)
778 if (debugger_bpt(regs))
780 if (check_bug_trap(regs)) {
784 _exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip);
790 /* Try to emulate it if we should. */
791 if (reason & (REASON_ILLEGAL | REASON_PRIVILEGED)) {
792 switch (emulate_instruction(regs)) {
795 emulate_single_step(regs);
798 _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
803 if (reason & REASON_PRIVILEGED)
804 _exception(SIGILL, regs, ILL_PRVOPC, regs->nip);
806 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
809 void alignment_exception(struct pt_regs *regs)
813 fixed = fix_alignment(regs);
816 regs->nip += 4; /* skip over emulated instruction */
817 emulate_single_step(regs);
821 /* Operand address was bad */
822 if (fixed == -EFAULT) {
824 _exception(SIGSEGV, regs, SEGV_ACCERR, regs->dar);
826 /* Search exception table */
827 bad_page_fault(regs, regs->dar, SIGSEGV);
830 _exception(SIGBUS, regs, BUS_ADRALN, regs->dar);
833 void StackOverflow(struct pt_regs *regs)
835 printk(KERN_CRIT "Kernel stack overflow in process %p, r1=%lx\n",
836 current, regs->gpr[1]);
839 panic("kernel stack overflow");
842 void nonrecoverable_exception(struct pt_regs *regs)
844 printk(KERN_ERR "Non-recoverable exception at PC=%lx MSR=%lx\n",
845 regs->nip, regs->msr);
847 die("nonrecoverable exception", regs, SIGKILL);
850 void trace_syscall(struct pt_regs *regs)
852 printk("Task: %p(%d), PC: %08lX/%08lX, Syscall: %3ld, Result: %s%ld %s\n",
853 current, current->pid, regs->nip, regs->link, regs->gpr[0],
854 regs->ccr&0x10000000?"Error=":"", regs->gpr[3], print_tainted());
857 void kernel_fp_unavailable_exception(struct pt_regs *regs)
859 printk(KERN_EMERG "Unrecoverable FP Unavailable Exception "
860 "%lx at %lx\n", regs->trap, regs->nip);
861 die("Unrecoverable FP Unavailable Exception", regs, SIGABRT);
864 void altivec_unavailable_exception(struct pt_regs *regs)
866 #if !defined(CONFIG_ALTIVEC)
867 if (user_mode(regs)) {
868 /* A user program has executed an altivec instruction,
869 but this kernel doesn't support altivec. */
870 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
874 printk(KERN_EMERG "Unrecoverable VMX/Altivec Unavailable Exception "
875 "%lx at %lx\n", regs->trap, regs->nip);
876 die("Unrecoverable VMX/Altivec Unavailable Exception", regs, SIGABRT);
879 void performance_monitor_exception(struct pt_regs *regs)
885 void SoftwareEmulation(struct pt_regs *regs)
887 extern int do_mathemu(struct pt_regs *);
888 extern int Soft_emulate_8xx(struct pt_regs *);
891 CHECK_FULL_REGS(regs);
893 if (!user_mode(regs)) {
895 die("Kernel Mode Software FPU Emulation", regs, SIGFPE);
898 #ifdef CONFIG_MATH_EMULATION
899 errcode = do_mathemu(regs);
901 errcode = Soft_emulate_8xx(regs);
905 _exception(SIGFPE, regs, 0, 0);
906 else if (errcode == -EFAULT)
907 _exception(SIGSEGV, regs, 0, 0);
909 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
911 emulate_single_step(regs);
913 #endif /* CONFIG_8xx */
915 #if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
917 void DebugException(struct pt_regs *regs, unsigned long debug_status)
919 if (debug_status & DBSR_IC) { /* instruction completion */
920 regs->msr &= ~MSR_DE;
921 if (user_mode(regs)) {
922 current->thread.dbcr0 &= ~DBCR0_IC;
924 /* Disable instruction completion */
925 mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) & ~DBCR0_IC);
926 /* Clear the instruction completion event */
927 mtspr(SPRN_DBSR, DBSR_IC);
928 if (debugger_sstep(regs))
931 _exception(SIGTRAP, regs, TRAP_TRACE, 0);
934 #endif /* CONFIG_4xx || CONFIG_BOOKE */
936 #if !defined(CONFIG_TAU_INT)
937 void TAUException(struct pt_regs *regs)
939 printk("TAU trap at PC: %lx, MSR: %lx, vector=%lx %s\n",
940 regs->nip, regs->msr, regs->trap, print_tainted());
942 #endif /* CONFIG_INT_TAU */
944 #ifdef CONFIG_ALTIVEC
945 void altivec_assist_exception(struct pt_regs *regs)
949 if (!user_mode(regs)) {
950 printk(KERN_EMERG "VMX/Altivec assist exception in kernel mode"
951 " at %lx\n", regs->nip);
952 die("Kernel VMX/Altivec assist exception", regs, SIGILL);
955 flush_altivec_to_thread(current);
957 err = emulate_altivec(regs);
959 regs->nip += 4; /* skip emulated instruction */
960 emulate_single_step(regs);
964 if (err == -EFAULT) {
965 /* got an error reading the instruction */
966 _exception(SIGSEGV, regs, SEGV_ACCERR, regs->nip);
968 /* didn't recognize the instruction */
969 /* XXX quick hack for now: set the non-Java bit in the VSCR */
970 if (printk_ratelimit())
971 printk(KERN_ERR "Unrecognized altivec instruction "
972 "in %s at %lx\n", current->comm, regs->nip);
973 current->thread.vscr.u[3] |= 0x10000;
976 #endif /* CONFIG_ALTIVEC */
978 #ifdef CONFIG_FSL_BOOKE
979 void CacheLockingException(struct pt_regs *regs, unsigned long address,
980 unsigned long error_code)
982 /* We treat cache locking instructions from the user
983 * as priv ops, in the future we could try to do
986 if (error_code & (ESR_DLK|ESR_ILK))
987 _exception(SIGILL, regs, ILL_PRVOPC, regs->nip);
990 #endif /* CONFIG_FSL_BOOKE */
993 void SPEFloatingPointException(struct pt_regs *regs)
995 unsigned long spefscr;
999 spefscr = current->thread.spefscr;
1000 fpexc_mode = current->thread.fpexc_mode;
1002 /* Hardware does not neccessarily set sticky
1003 * underflow/overflow/invalid flags */
1004 if ((spefscr & SPEFSCR_FOVF) && (fpexc_mode & PR_FP_EXC_OVF)) {
1006 spefscr |= SPEFSCR_FOVFS;
1008 else if ((spefscr & SPEFSCR_FUNF) && (fpexc_mode & PR_FP_EXC_UND)) {
1010 spefscr |= SPEFSCR_FUNFS;
1012 else if ((spefscr & SPEFSCR_FDBZ) && (fpexc_mode & PR_FP_EXC_DIV))
1014 else if ((spefscr & SPEFSCR_FINV) && (fpexc_mode & PR_FP_EXC_INV)) {
1016 spefscr |= SPEFSCR_FINVS;
1018 else if ((spefscr & (SPEFSCR_FG | SPEFSCR_FX)) && (fpexc_mode & PR_FP_EXC_RES))
1021 current->thread.spefscr = spefscr;
1023 _exception(SIGFPE, regs, code, regs->nip);
1029 * We enter here if we get an unrecoverable exception, that is, one
1030 * that happened at a point where the RI (recoverable interrupt) bit
1031 * in the MSR is 0. This indicates that SRR0/1 are live, and that
1032 * we therefore lost state by taking this exception.
1034 void unrecoverable_exception(struct pt_regs *regs)
1036 printk(KERN_EMERG "Unrecoverable exception %lx at %lx\n",
1037 regs->trap, regs->nip);
1038 die("Unrecoverable exception", regs, SIGABRT);
1041 #ifdef CONFIG_BOOKE_WDT
1043 * Default handler for a Watchdog exception,
1044 * spins until a reboot occurs
1046 void __attribute__ ((weak)) WatchdogHandler(struct pt_regs *regs)
1048 /* Generic WatchdogHandler, implement your own */
1049 mtspr(SPRN_TCR, mfspr(SPRN_TCR)&(~TCR_WIE));
1053 void WatchdogException(struct pt_regs *regs)
1055 printk (KERN_EMERG "PowerPC Book-E Watchdog Exception\n");
1056 WatchdogHandler(regs);
1061 * We enter here if we discover during exception entry that we are
1062 * running in supervisor mode with a userspace value in the stack pointer.
1064 void kernel_bad_stack(struct pt_regs *regs)
1066 printk(KERN_EMERG "Bad kernel stack pointer %lx at %lx\n",
1067 regs->gpr[1], regs->nip);
1068 die("Bad kernel stack pointer", regs, SIGABRT);
1071 void __init trap_init(void)