2 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
3 * Copyright 2007-2010 Freescale Semiconductor, Inc.
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.
10 * Modified by Cort Dougan (cort@cs.nmt.edu)
11 * and Paul Mackerras (paulus@samba.org)
15 * This file handles the architecture-dependent parts of hardware exceptions
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/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 #include <linux/context_tracking.h>
40 #include <asm/emulated_ops.h>
41 #include <asm/pgtable.h>
42 #include <asm/uaccess.h>
44 #include <asm/machdep.h>
50 #ifdef CONFIG_PMAC_BACKLIGHT
51 #include <asm/backlight.h>
54 #include <asm/firmware.h>
55 #include <asm/processor.h>
58 #include <asm/kexec.h>
59 #include <asm/ppc-opcode.h>
61 #include <asm/fadump.h>
62 #include <asm/switch_to.h>
64 #include <asm/debug.h>
66 #if defined(CONFIG_DEBUGGER) || defined(CONFIG_KEXEC)
67 int (*__debugger)(struct pt_regs *regs) __read_mostly;
68 int (*__debugger_ipi)(struct pt_regs *regs) __read_mostly;
69 int (*__debugger_bpt)(struct pt_regs *regs) __read_mostly;
70 int (*__debugger_sstep)(struct pt_regs *regs) __read_mostly;
71 int (*__debugger_iabr_match)(struct pt_regs *regs) __read_mostly;
72 int (*__debugger_break_match)(struct pt_regs *regs) __read_mostly;
73 int (*__debugger_fault_handler)(struct pt_regs *regs) __read_mostly;
75 EXPORT_SYMBOL(__debugger);
76 EXPORT_SYMBOL(__debugger_ipi);
77 EXPORT_SYMBOL(__debugger_bpt);
78 EXPORT_SYMBOL(__debugger_sstep);
79 EXPORT_SYMBOL(__debugger_iabr_match);
80 EXPORT_SYMBOL(__debugger_break_match);
81 EXPORT_SYMBOL(__debugger_fault_handler);
84 /* Transactional Memory trap debug */
86 #define TM_DEBUG(x...) printk(KERN_INFO x)
88 #define TM_DEBUG(x...) do { } while(0)
92 * Trap & Exception support
95 #ifdef CONFIG_PMAC_BACKLIGHT
96 static void pmac_backlight_unblank(void)
98 mutex_lock(&pmac_backlight_mutex);
100 struct backlight_properties *props;
102 props = &pmac_backlight->props;
103 props->brightness = props->max_brightness;
104 props->power = FB_BLANK_UNBLANK;
105 backlight_update_status(pmac_backlight);
107 mutex_unlock(&pmac_backlight_mutex);
110 static inline void pmac_backlight_unblank(void) { }
113 static arch_spinlock_t die_lock = __ARCH_SPIN_LOCK_UNLOCKED;
114 static int die_owner = -1;
115 static unsigned int die_nest_count;
116 static int die_counter;
118 static unsigned __kprobes long oops_begin(struct pt_regs *regs)
128 /* racy, but better than risking deadlock. */
129 raw_local_irq_save(flags);
130 cpu = smp_processor_id();
131 if (!arch_spin_trylock(&die_lock)) {
132 if (cpu == die_owner)
133 /* nested oops. should stop eventually */;
135 arch_spin_lock(&die_lock);
141 if (machine_is(powermac))
142 pmac_backlight_unblank();
146 static void __kprobes oops_end(unsigned long flags, struct pt_regs *regs,
151 add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
156 /* Nest count reaches zero, release the lock. */
157 arch_spin_unlock(&die_lock);
158 raw_local_irq_restore(flags);
160 crash_fadump(regs, "die oops");
163 * A system reset (0x100) is a request to dump, so we always send
164 * it through the crashdump code.
166 if (kexec_should_crash(current) || (TRAP(regs) == 0x100)) {
170 * We aren't the primary crash CPU. We need to send it
171 * to a holding pattern to avoid it ending up in the panic
174 crash_kexec_secondary(regs);
181 * While our oops output is serialised by a spinlock, output
182 * from panic() called below can race and corrupt it. If we
183 * know we are going to panic, delay for 1 second so we have a
184 * chance to get clean backtraces from all CPUs that are oopsing.
186 if (in_interrupt() || panic_on_oops || !current->pid ||
187 is_global_init(current)) {
188 mdelay(MSEC_PER_SEC);
192 panic("Fatal exception in interrupt");
194 panic("Fatal exception");
198 static int __kprobes __die(const char *str, struct pt_regs *regs, long err)
200 printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
201 #ifdef CONFIG_PREEMPT
205 printk("SMP NR_CPUS=%d ", NR_CPUS);
207 #ifdef CONFIG_DEBUG_PAGEALLOC
208 printk("DEBUG_PAGEALLOC ");
213 printk("%s\n", ppc_md.name ? ppc_md.name : "");
215 if (notify_die(DIE_OOPS, str, regs, err, 255, SIGSEGV) == NOTIFY_STOP)
224 void die(const char *str, struct pt_regs *regs, long err)
226 unsigned long flags = oops_begin(regs);
228 if (__die(str, regs, err))
230 oops_end(flags, regs, err);
233 void user_single_step_siginfo(struct task_struct *tsk,
234 struct pt_regs *regs, siginfo_t *info)
236 memset(info, 0, sizeof(*info));
237 info->si_signo = SIGTRAP;
238 info->si_code = TRAP_TRACE;
239 info->si_addr = (void __user *)regs->nip;
242 void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
245 const char fmt32[] = KERN_INFO "%s[%d]: unhandled signal %d " \
246 "at %08lx nip %08lx lr %08lx code %x\n";
247 const char fmt64[] = KERN_INFO "%s[%d]: unhandled signal %d " \
248 "at %016lx nip %016lx lr %016lx code %x\n";
250 if (!user_mode(regs)) {
251 die("Exception in kernel mode", regs, signr);
255 if (show_unhandled_signals && unhandled_signal(current, signr)) {
256 printk_ratelimited(regs->msr & MSR_64BIT ? fmt64 : fmt32,
257 current->comm, current->pid, signr,
258 addr, regs->nip, regs->link, code);
261 if (arch_irqs_disabled() && !arch_irq_disabled_regs(regs))
264 current->thread.trap_nr = code;
265 memset(&info, 0, sizeof(info));
266 info.si_signo = signr;
268 info.si_addr = (void __user *) addr;
269 force_sig_info(signr, &info, current);
273 void system_reset_exception(struct pt_regs *regs)
275 /* See if any machine dependent calls */
276 if (ppc_md.system_reset_exception) {
277 if (ppc_md.system_reset_exception(regs))
281 die("System Reset", regs, SIGABRT);
283 /* Must die if the interrupt is not recoverable */
284 if (!(regs->msr & MSR_RI))
285 panic("Unrecoverable System Reset");
287 /* What should we do here? We could issue a shutdown or hard reset. */
292 * I/O accesses can cause machine checks on powermacs.
293 * Check if the NIP corresponds to the address of a sync
294 * instruction for which there is an entry in the exception
296 * Note that the 601 only takes a machine check on TEA
297 * (transfer error ack) signal assertion, and does not
298 * set any of the top 16 bits of SRR1.
301 static inline int check_io_access(struct pt_regs *regs)
304 unsigned long msr = regs->msr;
305 const struct exception_table_entry *entry;
306 unsigned int *nip = (unsigned int *)regs->nip;
308 if (((msr & 0xffff0000) == 0 || (msr & (0x80000 | 0x40000)))
309 && (entry = search_exception_tables(regs->nip)) != NULL) {
311 * Check that it's a sync instruction, or somewhere
312 * in the twi; isync; nop sequence that inb/inw/inl uses.
313 * As the address is in the exception table
314 * we should be able to read the instr there.
315 * For the debug message, we look at the preceding
318 if (*nip == 0x60000000) /* nop */
320 else if (*nip == 0x4c00012c) /* isync */
322 if (*nip == 0x7c0004ac || (*nip >> 26) == 3) {
327 rb = (*nip >> 11) & 0x1f;
328 printk(KERN_DEBUG "%s bad port %lx at %p\n",
329 (*nip & 0x100)? "OUT to": "IN from",
330 regs->gpr[rb] - _IO_BASE, nip);
332 regs->nip = entry->fixup;
336 #endif /* CONFIG_PPC32 */
340 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
341 /* On 4xx, the reason for the machine check or program exception
343 #define get_reason(regs) ((regs)->dsisr)
344 #ifndef CONFIG_FSL_BOOKE
345 #define get_mc_reason(regs) ((regs)->dsisr)
347 #define get_mc_reason(regs) (mfspr(SPRN_MCSR))
349 #define REASON_FP ESR_FP
350 #define REASON_ILLEGAL (ESR_PIL | ESR_PUO)
351 #define REASON_PRIVILEGED ESR_PPR
352 #define REASON_TRAP ESR_PTR
354 /* single-step stuff */
355 #define single_stepping(regs) (current->thread.dbcr0 & DBCR0_IC)
356 #define clear_single_step(regs) (current->thread.dbcr0 &= ~DBCR0_IC)
359 /* On non-4xx, the reason for the machine check or program
360 exception is in the MSR. */
361 #define get_reason(regs) ((regs)->msr)
362 #define get_mc_reason(regs) ((regs)->msr)
363 #define REASON_TM 0x200000
364 #define REASON_FP 0x100000
365 #define REASON_ILLEGAL 0x80000
366 #define REASON_PRIVILEGED 0x40000
367 #define REASON_TRAP 0x20000
369 #define single_stepping(regs) ((regs)->msr & MSR_SE)
370 #define clear_single_step(regs) ((regs)->msr &= ~MSR_SE)
373 #if defined(CONFIG_4xx)
374 int machine_check_4xx(struct pt_regs *regs)
376 unsigned long reason = get_mc_reason(regs);
378 if (reason & ESR_IMCP) {
379 printk("Instruction");
380 mtspr(SPRN_ESR, reason & ~ESR_IMCP);
383 printk(" machine check in kernel mode.\n");
388 int machine_check_440A(struct pt_regs *regs)
390 unsigned long reason = get_mc_reason(regs);
392 printk("Machine check in kernel mode.\n");
393 if (reason & ESR_IMCP){
394 printk("Instruction Synchronous Machine Check exception\n");
395 mtspr(SPRN_ESR, reason & ~ESR_IMCP);
398 u32 mcsr = mfspr(SPRN_MCSR);
400 printk("Instruction Read PLB Error\n");
402 printk("Data Read PLB Error\n");
404 printk("Data Write PLB Error\n");
405 if (mcsr & MCSR_TLBP)
406 printk("TLB Parity Error\n");
407 if (mcsr & MCSR_ICP){
408 flush_instruction_cache();
409 printk("I-Cache Parity Error\n");
411 if (mcsr & MCSR_DCSP)
412 printk("D-Cache Search Parity Error\n");
413 if (mcsr & MCSR_DCFP)
414 printk("D-Cache Flush Parity Error\n");
415 if (mcsr & MCSR_IMPE)
416 printk("Machine Check exception is imprecise\n");
419 mtspr(SPRN_MCSR, mcsr);
424 int machine_check_47x(struct pt_regs *regs)
426 unsigned long reason = get_mc_reason(regs);
429 printk(KERN_ERR "Machine check in kernel mode.\n");
430 if (reason & ESR_IMCP) {
432 "Instruction Synchronous Machine Check exception\n");
433 mtspr(SPRN_ESR, reason & ~ESR_IMCP);
436 mcsr = mfspr(SPRN_MCSR);
438 printk(KERN_ERR "Instruction Read PLB Error\n");
440 printk(KERN_ERR "Data Read PLB Error\n");
442 printk(KERN_ERR "Data Write PLB Error\n");
443 if (mcsr & MCSR_TLBP)
444 printk(KERN_ERR "TLB Parity Error\n");
445 if (mcsr & MCSR_ICP) {
446 flush_instruction_cache();
447 printk(KERN_ERR "I-Cache Parity Error\n");
449 if (mcsr & MCSR_DCSP)
450 printk(KERN_ERR "D-Cache Search Parity Error\n");
451 if (mcsr & PPC47x_MCSR_GPR)
452 printk(KERN_ERR "GPR Parity Error\n");
453 if (mcsr & PPC47x_MCSR_FPR)
454 printk(KERN_ERR "FPR Parity Error\n");
455 if (mcsr & PPC47x_MCSR_IPR)
456 printk(KERN_ERR "Machine Check exception is imprecise\n");
459 mtspr(SPRN_MCSR, mcsr);
463 #elif defined(CONFIG_E500)
464 int machine_check_e500mc(struct pt_regs *regs)
466 unsigned long mcsr = mfspr(SPRN_MCSR);
467 unsigned long reason = mcsr;
470 if (reason & MCSR_LD) {
471 recoverable = fsl_rio_mcheck_exception(regs);
472 if (recoverable == 1)
476 printk("Machine check in kernel mode.\n");
477 printk("Caused by (from MCSR=%lx): ", reason);
479 if (reason & MCSR_MCP)
480 printk("Machine Check Signal\n");
482 if (reason & MCSR_ICPERR) {
483 printk("Instruction Cache Parity Error\n");
486 * This is recoverable by invalidating the i-cache.
488 mtspr(SPRN_L1CSR1, mfspr(SPRN_L1CSR1) | L1CSR1_ICFI);
489 while (mfspr(SPRN_L1CSR1) & L1CSR1_ICFI)
493 * This will generally be accompanied by an instruction
494 * fetch error report -- only treat MCSR_IF as fatal
495 * if it wasn't due to an L1 parity error.
500 if (reason & MCSR_DCPERR_MC) {
501 printk("Data Cache Parity Error\n");
504 * In write shadow mode we auto-recover from the error, but it
505 * may still get logged and cause a machine check. We should
506 * only treat the non-write shadow case as non-recoverable.
508 if (!(mfspr(SPRN_L1CSR2) & L1CSR2_DCWS))
512 if (reason & MCSR_L2MMU_MHIT) {
513 printk("Hit on multiple TLB entries\n");
517 if (reason & MCSR_NMI)
518 printk("Non-maskable interrupt\n");
520 if (reason & MCSR_IF) {
521 printk("Instruction Fetch Error Report\n");
525 if (reason & MCSR_LD) {
526 printk("Load Error Report\n");
530 if (reason & MCSR_ST) {
531 printk("Store Error Report\n");
535 if (reason & MCSR_LDG) {
536 printk("Guarded Load Error Report\n");
540 if (reason & MCSR_TLBSYNC)
541 printk("Simultaneous tlbsync operations\n");
543 if (reason & MCSR_BSL2_ERR) {
544 printk("Level 2 Cache Error\n");
548 if (reason & MCSR_MAV) {
551 addr = mfspr(SPRN_MCAR);
552 addr |= (u64)mfspr(SPRN_MCARU) << 32;
554 printk("Machine Check %s Address: %#llx\n",
555 reason & MCSR_MEA ? "Effective" : "Physical", addr);
559 mtspr(SPRN_MCSR, mcsr);
560 return mfspr(SPRN_MCSR) == 0 && recoverable;
563 int machine_check_e500(struct pt_regs *regs)
565 unsigned long reason = get_mc_reason(regs);
567 if (reason & MCSR_BUS_RBERR) {
568 if (fsl_rio_mcheck_exception(regs))
572 printk("Machine check in kernel mode.\n");
573 printk("Caused by (from MCSR=%lx): ", reason);
575 if (reason & MCSR_MCP)
576 printk("Machine Check Signal\n");
577 if (reason & MCSR_ICPERR)
578 printk("Instruction Cache Parity Error\n");
579 if (reason & MCSR_DCP_PERR)
580 printk("Data Cache Push Parity Error\n");
581 if (reason & MCSR_DCPERR)
582 printk("Data Cache Parity Error\n");
583 if (reason & MCSR_BUS_IAERR)
584 printk("Bus - Instruction Address Error\n");
585 if (reason & MCSR_BUS_RAERR)
586 printk("Bus - Read Address Error\n");
587 if (reason & MCSR_BUS_WAERR)
588 printk("Bus - Write Address Error\n");
589 if (reason & MCSR_BUS_IBERR)
590 printk("Bus - Instruction Data Error\n");
591 if (reason & MCSR_BUS_RBERR)
592 printk("Bus - Read Data Bus Error\n");
593 if (reason & MCSR_BUS_WBERR)
594 printk("Bus - Read Data Bus Error\n");
595 if (reason & MCSR_BUS_IPERR)
596 printk("Bus - Instruction Parity Error\n");
597 if (reason & MCSR_BUS_RPERR)
598 printk("Bus - Read Parity Error\n");
603 int machine_check_generic(struct pt_regs *regs)
607 #elif defined(CONFIG_E200)
608 int machine_check_e200(struct pt_regs *regs)
610 unsigned long reason = get_mc_reason(regs);
612 printk("Machine check in kernel mode.\n");
613 printk("Caused by (from MCSR=%lx): ", reason);
615 if (reason & MCSR_MCP)
616 printk("Machine Check Signal\n");
617 if (reason & MCSR_CP_PERR)
618 printk("Cache Push Parity Error\n");
619 if (reason & MCSR_CPERR)
620 printk("Cache Parity Error\n");
621 if (reason & MCSR_EXCP_ERR)
622 printk("ISI, ITLB, or Bus Error on first instruction fetch for an exception handler\n");
623 if (reason & MCSR_BUS_IRERR)
624 printk("Bus - Read Bus Error on instruction fetch\n");
625 if (reason & MCSR_BUS_DRERR)
626 printk("Bus - Read Bus Error on data load\n");
627 if (reason & MCSR_BUS_WRERR)
628 printk("Bus - Write Bus Error on buffered store or cache line push\n");
633 int machine_check_generic(struct pt_regs *regs)
635 unsigned long reason = get_mc_reason(regs);
637 printk("Machine check in kernel mode.\n");
638 printk("Caused by (from SRR1=%lx): ", reason);
639 switch (reason & 0x601F0000) {
641 printk("Machine check signal\n");
643 case 0: /* for 601 */
645 case 0x140000: /* 7450 MSS error and TEA */
646 printk("Transfer error ack signal\n");
649 printk("Data parity error signal\n");
652 printk("Address parity error signal\n");
655 printk("L1 Data Cache error\n");
658 printk("L1 Instruction Cache error\n");
661 printk("L2 data cache parity error\n");
664 printk("Unknown values in msr\n");
668 #endif /* everything else */
670 void machine_check_exception(struct pt_regs *regs)
672 enum ctx_state prev_state = exception_enter();
675 __get_cpu_var(irq_stat).mce_exceptions++;
677 /* See if any machine dependent calls. In theory, we would want
678 * to call the CPU first, and call the ppc_md. one if the CPU
679 * one returns a positive number. However there is existing code
680 * that assumes the board gets a first chance, so let's keep it
681 * that way for now and fix things later. --BenH.
683 if (ppc_md.machine_check_exception)
684 recover = ppc_md.machine_check_exception(regs);
685 else if (cur_cpu_spec->machine_check)
686 recover = cur_cpu_spec->machine_check(regs);
691 #if defined(CONFIG_8xx) && defined(CONFIG_PCI)
692 /* the qspan pci read routines can cause machine checks -- Cort
694 * yuck !!! that totally needs to go away ! There are better ways
695 * to deal with that than having a wart in the mcheck handler.
698 bad_page_fault(regs, regs->dar, SIGBUS);
702 if (debugger_fault_handler(regs))
705 if (check_io_access(regs))
708 die("Machine check", regs, SIGBUS);
710 /* Must die if the interrupt is not recoverable */
711 if (!(regs->msr & MSR_RI))
712 panic("Unrecoverable Machine check");
715 exception_exit(prev_state);
718 void SMIException(struct pt_regs *regs)
720 die("System Management Interrupt", regs, SIGABRT);
723 void unknown_exception(struct pt_regs *regs)
725 enum ctx_state prev_state = exception_enter();
727 printk("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
728 regs->nip, regs->msr, regs->trap);
730 _exception(SIGTRAP, regs, 0, 0);
732 exception_exit(prev_state);
735 void instruction_breakpoint_exception(struct pt_regs *regs)
737 enum ctx_state prev_state = exception_enter();
739 if (notify_die(DIE_IABR_MATCH, "iabr_match", regs, 5,
740 5, SIGTRAP) == NOTIFY_STOP)
742 if (debugger_iabr_match(regs))
744 _exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip);
747 exception_exit(prev_state);
750 void RunModeException(struct pt_regs *regs)
752 _exception(SIGTRAP, regs, 0, 0);
755 void __kprobes single_step_exception(struct pt_regs *regs)
757 enum ctx_state prev_state = exception_enter();
759 clear_single_step(regs);
761 if (notify_die(DIE_SSTEP, "single_step", regs, 5,
762 5, SIGTRAP) == NOTIFY_STOP)
764 if (debugger_sstep(regs))
767 _exception(SIGTRAP, regs, TRAP_TRACE, regs->nip);
770 exception_exit(prev_state);
774 * After we have successfully emulated an instruction, we have to
775 * check if the instruction was being single-stepped, and if so,
776 * pretend we got a single-step exception. This was pointed out
777 * by Kumar Gala. -- paulus
779 static void emulate_single_step(struct pt_regs *regs)
781 if (single_stepping(regs))
782 single_step_exception(regs);
785 static inline int __parse_fpscr(unsigned long fpscr)
789 /* Invalid operation */
790 if ((fpscr & FPSCR_VE) && (fpscr & FPSCR_VX))
794 else if ((fpscr & FPSCR_OE) && (fpscr & FPSCR_OX))
798 else if ((fpscr & FPSCR_UE) && (fpscr & FPSCR_UX))
802 else if ((fpscr & FPSCR_ZE) && (fpscr & FPSCR_ZX))
806 else if ((fpscr & FPSCR_XE) && (fpscr & FPSCR_XX))
812 static void parse_fpe(struct pt_regs *regs)
816 flush_fp_to_thread(current);
818 code = __parse_fpscr(current->thread.fpscr.val);
820 _exception(SIGFPE, regs, code, regs->nip);
824 * Illegal instruction emulation support. Originally written to
825 * provide the PVR to user applications using the mfspr rd, PVR.
826 * Return non-zero if we can't emulate, or -EFAULT if the associated
827 * memory access caused an access fault. Return zero on success.
829 * There are a couple of ways to do this, either "decode" the instruction
830 * or directly match lots of bits. In this case, matching lots of
831 * bits is faster and easier.
834 static int emulate_string_inst(struct pt_regs *regs, u32 instword)
836 u8 rT = (instword >> 21) & 0x1f;
837 u8 rA = (instword >> 16) & 0x1f;
838 u8 NB_RB = (instword >> 11) & 0x1f;
843 /* Early out if we are an invalid form of lswx */
844 if ((instword & PPC_INST_STRING_MASK) == PPC_INST_LSWX)
845 if ((rT == rA) || (rT == NB_RB))
848 EA = (rA == 0) ? 0 : regs->gpr[rA];
850 switch (instword & PPC_INST_STRING_MASK) {
854 num_bytes = regs->xer & 0x7f;
858 num_bytes = (NB_RB == 0) ? 32 : NB_RB;
864 while (num_bytes != 0)
867 u32 shift = 8 * (3 - (pos & 0x3));
869 switch ((instword & PPC_INST_STRING_MASK)) {
872 if (get_user(val, (u8 __user *)EA))
874 /* first time updating this reg,
878 regs->gpr[rT] |= val << shift;
882 val = regs->gpr[rT] >> shift;
883 if (put_user(val, (u8 __user *)EA))
887 /* move EA to next address */
891 /* manage our position within the register */
902 static int emulate_popcntb_inst(struct pt_regs *regs, u32 instword)
907 ra = (instword >> 16) & 0x1f;
908 rs = (instword >> 21) & 0x1f;
911 tmp = tmp - ((tmp >> 1) & 0x5555555555555555ULL);
912 tmp = (tmp & 0x3333333333333333ULL) + ((tmp >> 2) & 0x3333333333333333ULL);
913 tmp = (tmp + (tmp >> 4)) & 0x0f0f0f0f0f0f0f0fULL;
919 static int emulate_isel(struct pt_regs *regs, u32 instword)
921 u8 rT = (instword >> 21) & 0x1f;
922 u8 rA = (instword >> 16) & 0x1f;
923 u8 rB = (instword >> 11) & 0x1f;
924 u8 BC = (instword >> 6) & 0x1f;
928 tmp = (rA == 0) ? 0 : regs->gpr[rA];
929 bit = (regs->ccr >> (31 - BC)) & 0x1;
931 regs->gpr[rT] = bit ? tmp : regs->gpr[rB];
936 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
937 static inline bool tm_abort_check(struct pt_regs *regs, int cause)
939 /* If we're emulating a load/store in an active transaction, we cannot
940 * emulate it as the kernel operates in transaction suspended context.
941 * We need to abort the transaction. This creates a persistent TM
942 * abort so tell the user what caused it with a new code.
944 if (MSR_TM_TRANSACTIONAL(regs->msr)) {
952 static inline bool tm_abort_check(struct pt_regs *regs, int reason)
958 static int emulate_instruction(struct pt_regs *regs)
963 if (!user_mode(regs) || (regs->msr & MSR_LE))
965 CHECK_FULL_REGS(regs);
967 if (get_user(instword, (u32 __user *)(regs->nip)))
970 /* Emulate the mfspr rD, PVR. */
971 if ((instword & PPC_INST_MFSPR_PVR_MASK) == PPC_INST_MFSPR_PVR) {
972 PPC_WARN_EMULATED(mfpvr, regs);
973 rd = (instword >> 21) & 0x1f;
974 regs->gpr[rd] = mfspr(SPRN_PVR);
978 /* Emulating the dcba insn is just a no-op. */
979 if ((instword & PPC_INST_DCBA_MASK) == PPC_INST_DCBA) {
980 PPC_WARN_EMULATED(dcba, regs);
984 /* Emulate the mcrxr insn. */
985 if ((instword & PPC_INST_MCRXR_MASK) == PPC_INST_MCRXR) {
986 int shift = (instword >> 21) & 0x1c;
987 unsigned long msk = 0xf0000000UL >> shift;
989 PPC_WARN_EMULATED(mcrxr, regs);
990 regs->ccr = (regs->ccr & ~msk) | ((regs->xer >> shift) & msk);
991 regs->xer &= ~0xf0000000UL;
995 /* Emulate load/store string insn. */
996 if ((instword & PPC_INST_STRING_GEN_MASK) == PPC_INST_STRING) {
997 if (tm_abort_check(regs,
998 TM_CAUSE_EMULATE | TM_CAUSE_PERSISTENT))
1000 PPC_WARN_EMULATED(string, regs);
1001 return emulate_string_inst(regs, instword);
1004 /* Emulate the popcntb (Population Count Bytes) instruction. */
1005 if ((instword & PPC_INST_POPCNTB_MASK) == PPC_INST_POPCNTB) {
1006 PPC_WARN_EMULATED(popcntb, regs);
1007 return emulate_popcntb_inst(regs, instword);
1010 /* Emulate isel (Integer Select) instruction */
1011 if ((instword & PPC_INST_ISEL_MASK) == PPC_INST_ISEL) {
1012 PPC_WARN_EMULATED(isel, regs);
1013 return emulate_isel(regs, instword);
1017 /* Emulate the mfspr rD, DSCR. */
1018 if ((((instword & PPC_INST_MFSPR_DSCR_USER_MASK) ==
1019 PPC_INST_MFSPR_DSCR_USER) ||
1020 ((instword & PPC_INST_MFSPR_DSCR_MASK) ==
1021 PPC_INST_MFSPR_DSCR)) &&
1022 cpu_has_feature(CPU_FTR_DSCR)) {
1023 PPC_WARN_EMULATED(mfdscr, regs);
1024 rd = (instword >> 21) & 0x1f;
1025 regs->gpr[rd] = mfspr(SPRN_DSCR);
1028 /* Emulate the mtspr DSCR, rD. */
1029 if ((((instword & PPC_INST_MTSPR_DSCR_USER_MASK) ==
1030 PPC_INST_MTSPR_DSCR_USER) ||
1031 ((instword & PPC_INST_MTSPR_DSCR_MASK) ==
1032 PPC_INST_MTSPR_DSCR)) &&
1033 cpu_has_feature(CPU_FTR_DSCR)) {
1034 PPC_WARN_EMULATED(mtdscr, regs);
1035 rd = (instword >> 21) & 0x1f;
1036 current->thread.dscr = regs->gpr[rd];
1037 current->thread.dscr_inherit = 1;
1038 mtspr(SPRN_DSCR, current->thread.dscr);
1046 int is_valid_bugaddr(unsigned long addr)
1048 return is_kernel_addr(addr);
1051 void __kprobes program_check_exception(struct pt_regs *regs)
1053 enum ctx_state prev_state = exception_enter();
1054 unsigned int reason = get_reason(regs);
1055 extern int do_mathemu(struct pt_regs *regs);
1057 /* We can now get here via a FP Unavailable exception if the core
1058 * has no FPU, in that case the reason flags will be 0 */
1060 if (reason & REASON_FP) {
1061 /* IEEE FP exception */
1065 if (reason & REASON_TRAP) {
1066 /* Debugger is first in line to stop recursive faults in
1067 * rcu_lock, notify_die, or atomic_notifier_call_chain */
1068 if (debugger_bpt(regs))
1071 /* trap exception */
1072 if (notify_die(DIE_BPT, "breakpoint", regs, 5, 5, SIGTRAP)
1076 if (!(regs->msr & MSR_PR) && /* not user-mode */
1077 report_bug(regs->nip, regs) == BUG_TRAP_TYPE_WARN) {
1081 _exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip);
1084 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1085 if (reason & REASON_TM) {
1086 /* This is a TM "Bad Thing Exception" program check.
1088 * - An rfid/hrfid/mtmsrd attempts to cause an illegal
1089 * transition in TM states.
1090 * - A trechkpt is attempted when transactional.
1091 * - A treclaim is attempted when non transactional.
1092 * - A tend is illegally attempted.
1093 * - writing a TM SPR when transactional.
1095 if (!user_mode(regs) &&
1096 report_bug(regs->nip, regs) == BUG_TRAP_TYPE_WARN) {
1100 /* If usermode caused this, it's done something illegal and
1101 * gets a SIGILL slap on the wrist. We call it an illegal
1102 * operand to distinguish from the instruction just being bad
1103 * (e.g. executing a 'tend' on a CPU without TM!); it's an
1104 * illegal /placement/ of a valid instruction.
1106 if (user_mode(regs)) {
1107 _exception(SIGILL, regs, ILL_ILLOPN, regs->nip);
1110 printk(KERN_EMERG "Unexpected TM Bad Thing exception "
1111 "at %lx (msr 0x%x)\n", regs->nip, reason);
1112 die("Unrecoverable exception", regs, SIGABRT);
1117 /* We restore the interrupt state now */
1118 if (!arch_irq_disabled_regs(regs))
1121 #ifdef CONFIG_MATH_EMULATION
1122 /* (reason & REASON_ILLEGAL) would be the obvious thing here,
1123 * but there seems to be a hardware bug on the 405GP (RevD)
1124 * that means ESR is sometimes set incorrectly - either to
1125 * ESR_DST (!?) or 0. In the process of chasing this with the
1126 * hardware people - not sure if it can happen on any illegal
1127 * instruction or only on FP instructions, whether there is a
1128 * pattern to occurrences etc. -dgibson 31/Mar/2003 */
1129 switch (do_mathemu(regs)) {
1131 emulate_single_step(regs);
1135 code = __parse_fpscr(current->thread.fpscr.val);
1136 _exception(SIGFPE, regs, code, regs->nip);
1140 _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
1143 /* fall through on any other errors */
1144 #endif /* CONFIG_MATH_EMULATION */
1146 /* Try to emulate it if we should. */
1147 if (reason & (REASON_ILLEGAL | REASON_PRIVILEGED)) {
1148 switch (emulate_instruction(regs)) {
1151 emulate_single_step(regs);
1154 _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
1159 if (reason & REASON_PRIVILEGED)
1160 _exception(SIGILL, regs, ILL_PRVOPC, regs->nip);
1162 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
1165 exception_exit(prev_state);
1168 void alignment_exception(struct pt_regs *regs)
1170 enum ctx_state prev_state = exception_enter();
1171 int sig, code, fixed = 0;
1173 /* We restore the interrupt state now */
1174 if (!arch_irq_disabled_regs(regs))
1177 if (tm_abort_check(regs, TM_CAUSE_ALIGNMENT | TM_CAUSE_PERSISTENT))
1180 /* we don't implement logging of alignment exceptions */
1181 if (!(current->thread.align_ctl & PR_UNALIGN_SIGBUS))
1182 fixed = fix_alignment(regs);
1185 regs->nip += 4; /* skip over emulated instruction */
1186 emulate_single_step(regs);
1190 /* Operand address was bad */
1191 if (fixed == -EFAULT) {
1198 if (user_mode(regs))
1199 _exception(sig, regs, code, regs->dar);
1201 bad_page_fault(regs, regs->dar, sig);
1204 exception_exit(prev_state);
1207 void StackOverflow(struct pt_regs *regs)
1209 printk(KERN_CRIT "Kernel stack overflow in process %p, r1=%lx\n",
1210 current, regs->gpr[1]);
1213 panic("kernel stack overflow");
1216 void nonrecoverable_exception(struct pt_regs *regs)
1218 printk(KERN_ERR "Non-recoverable exception at PC=%lx MSR=%lx\n",
1219 regs->nip, regs->msr);
1221 die("nonrecoverable exception", regs, SIGKILL);
1224 void trace_syscall(struct pt_regs *regs)
1226 printk("Task: %p(%d), PC: %08lX/%08lX, Syscall: %3ld, Result: %s%ld %s\n",
1227 current, task_pid_nr(current), regs->nip, regs->link, regs->gpr[0],
1228 regs->ccr&0x10000000?"Error=":"", regs->gpr[3], print_tainted());
1231 void kernel_fp_unavailable_exception(struct pt_regs *regs)
1233 enum ctx_state prev_state = exception_enter();
1235 printk(KERN_EMERG "Unrecoverable FP Unavailable Exception "
1236 "%lx at %lx\n", regs->trap, regs->nip);
1237 die("Unrecoverable FP Unavailable Exception", regs, SIGABRT);
1239 exception_exit(prev_state);
1242 void altivec_unavailable_exception(struct pt_regs *regs)
1244 enum ctx_state prev_state = exception_enter();
1246 if (user_mode(regs)) {
1247 /* A user program has executed an altivec instruction,
1248 but this kernel doesn't support altivec. */
1249 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
1253 printk(KERN_EMERG "Unrecoverable VMX/Altivec Unavailable Exception "
1254 "%lx at %lx\n", regs->trap, regs->nip);
1255 die("Unrecoverable VMX/Altivec Unavailable Exception", regs, SIGABRT);
1258 exception_exit(prev_state);
1261 void vsx_unavailable_exception(struct pt_regs *regs)
1263 if (user_mode(regs)) {
1264 /* A user program has executed an vsx instruction,
1265 but this kernel doesn't support vsx. */
1266 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
1270 printk(KERN_EMERG "Unrecoverable VSX Unavailable Exception "
1271 "%lx at %lx\n", regs->trap, regs->nip);
1272 die("Unrecoverable VSX Unavailable Exception", regs, SIGABRT);
1275 void tm_unavailable_exception(struct pt_regs *regs)
1277 /* We restore the interrupt state now */
1278 if (!arch_irq_disabled_regs(regs))
1281 /* Currently we never expect a TMU exception. Catch
1282 * this and kill the process!
1284 printk(KERN_EMERG "Unexpected TM unavailable exception at %lx "
1286 regs->nip, regs->msr);
1288 if (user_mode(regs)) {
1289 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
1293 die("Unexpected TM unavailable exception", regs, SIGABRT);
1296 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1298 extern void do_load_up_fpu(struct pt_regs *regs);
1300 void fp_unavailable_tm(struct pt_regs *regs)
1302 /* Note: This does not handle any kind of FP laziness. */
1304 TM_DEBUG("FP Unavailable trap whilst transactional at 0x%lx, MSR=%lx\n",
1305 regs->nip, regs->msr);
1308 /* We can only have got here if the task started using FP after
1309 * beginning the transaction. So, the transactional regs are just a
1310 * copy of the checkpointed ones. But, we still need to recheckpoint
1311 * as we're enabling FP for the process; it will return, abort the
1312 * transaction, and probably retry but now with FP enabled. So the
1313 * checkpointed FP registers need to be loaded.
1315 tm_reclaim(¤t->thread, current->thread.regs->msr,
1317 /* Reclaim didn't save out any FPRs to transact_fprs. */
1319 /* Enable FP for the task: */
1320 regs->msr |= (MSR_FP | current->thread.fpexc_mode);
1322 /* This loads and recheckpoints the FP registers from
1323 * thread.fpr[]. They will remain in registers after the
1324 * checkpoint so we don't need to reload them after.
1326 tm_recheckpoint(¤t->thread, regs->msr);
1329 #ifdef CONFIG_ALTIVEC
1330 extern void do_load_up_altivec(struct pt_regs *regs);
1332 void altivec_unavailable_tm(struct pt_regs *regs)
1334 /* See the comments in fp_unavailable_tm(). This function operates
1338 TM_DEBUG("Vector Unavailable trap whilst transactional at 0x%lx,"
1340 regs->nip, regs->msr);
1342 tm_reclaim(¤t->thread, current->thread.regs->msr,
1344 regs->msr |= MSR_VEC;
1345 tm_recheckpoint(¤t->thread, regs->msr);
1346 current->thread.used_vr = 1;
1351 void vsx_unavailable_tm(struct pt_regs *regs)
1353 /* See the comments in fp_unavailable_tm(). This works similarly,
1354 * though we're loading both FP and VEC registers in here.
1356 * If FP isn't in use, load FP regs. If VEC isn't in use, load VEC
1357 * regs. Either way, set MSR_VSX.
1360 TM_DEBUG("VSX Unavailable trap whilst transactional at 0x%lx,"
1362 regs->nip, regs->msr);
1365 /* This reclaims FP and/or VR regs if they're already enabled */
1366 tm_reclaim(¤t->thread, current->thread.regs->msr,
1369 regs->msr |= MSR_VEC | MSR_FP | current->thread.fpexc_mode |
1371 /* This loads & recheckpoints FP and VRs. */
1372 tm_recheckpoint(¤t->thread, regs->msr);
1373 current->thread.used_vsr = 1;
1376 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
1378 void performance_monitor_exception(struct pt_regs *regs)
1380 __get_cpu_var(irq_stat).pmu_irqs++;
1386 void SoftwareEmulation(struct pt_regs *regs)
1388 extern int do_mathemu(struct pt_regs *);
1389 extern int Soft_emulate_8xx(struct pt_regs *);
1390 #if defined(CONFIG_MATH_EMULATION) || defined(CONFIG_8XX_MINIMAL_FPEMU)
1394 CHECK_FULL_REGS(regs);
1396 if (!user_mode(regs)) {
1398 die("Kernel Mode Software FPU Emulation", regs, SIGFPE);
1401 #ifdef CONFIG_MATH_EMULATION
1402 errcode = do_mathemu(regs);
1404 PPC_WARN_EMULATED(math, regs);
1408 emulate_single_step(regs);
1412 code = __parse_fpscr(current->thread.fpscr.val);
1413 _exception(SIGFPE, regs, code, regs->nip);
1417 _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
1420 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
1424 #elif defined(CONFIG_8XX_MINIMAL_FPEMU)
1425 errcode = Soft_emulate_8xx(regs);
1427 PPC_WARN_EMULATED(8xx, regs);
1431 emulate_single_step(regs);
1434 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
1437 _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
1441 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
1444 #endif /* CONFIG_8xx */
1446 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
1447 static void handle_debug(struct pt_regs *regs, unsigned long debug_status)
1451 * Determine the cause of the debug event, clear the
1452 * event flags and send a trap to the handler. Torez
1454 if (debug_status & (DBSR_DAC1R | DBSR_DAC1W)) {
1455 dbcr_dac(current) &= ~(DBCR_DAC1R | DBCR_DAC1W);
1456 #ifdef CONFIG_PPC_ADV_DEBUG_DAC_RANGE
1457 current->thread.dbcr2 &= ~DBCR2_DAC12MODE;
1459 do_send_trap(regs, mfspr(SPRN_DAC1), debug_status, TRAP_HWBKPT,
1462 } else if (debug_status & (DBSR_DAC2R | DBSR_DAC2W)) {
1463 dbcr_dac(current) &= ~(DBCR_DAC2R | DBCR_DAC2W);
1464 do_send_trap(regs, mfspr(SPRN_DAC2), debug_status, TRAP_HWBKPT,
1467 } else if (debug_status & DBSR_IAC1) {
1468 current->thread.dbcr0 &= ~DBCR0_IAC1;
1469 dbcr_iac_range(current) &= ~DBCR_IAC12MODE;
1470 do_send_trap(regs, mfspr(SPRN_IAC1), debug_status, TRAP_HWBKPT,
1473 } else if (debug_status & DBSR_IAC2) {
1474 current->thread.dbcr0 &= ~DBCR0_IAC2;
1475 do_send_trap(regs, mfspr(SPRN_IAC2), debug_status, TRAP_HWBKPT,
1478 } else if (debug_status & DBSR_IAC3) {
1479 current->thread.dbcr0 &= ~DBCR0_IAC3;
1480 dbcr_iac_range(current) &= ~DBCR_IAC34MODE;
1481 do_send_trap(regs, mfspr(SPRN_IAC3), debug_status, TRAP_HWBKPT,
1484 } else if (debug_status & DBSR_IAC4) {
1485 current->thread.dbcr0 &= ~DBCR0_IAC4;
1486 do_send_trap(regs, mfspr(SPRN_IAC4), debug_status, TRAP_HWBKPT,
1491 * At the point this routine was called, the MSR(DE) was turned off.
1492 * Check all other debug flags and see if that bit needs to be turned
1495 if (DBCR_ACTIVE_EVENTS(current->thread.dbcr0, current->thread.dbcr1))
1496 regs->msr |= MSR_DE;
1498 /* Make sure the IDM flag is off */
1499 current->thread.dbcr0 &= ~DBCR0_IDM;
1502 mtspr(SPRN_DBCR0, current->thread.dbcr0);
1505 void __kprobes DebugException(struct pt_regs *regs, unsigned long debug_status)
1507 current->thread.dbsr = debug_status;
1509 /* Hack alert: On BookE, Branch Taken stops on the branch itself, while
1510 * on server, it stops on the target of the branch. In order to simulate
1511 * the server behaviour, we thus restart right away with a single step
1512 * instead of stopping here when hitting a BT
1514 if (debug_status & DBSR_BT) {
1515 regs->msr &= ~MSR_DE;
1518 mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) & ~DBCR0_BT);
1519 /* Clear the BT event */
1520 mtspr(SPRN_DBSR, DBSR_BT);
1522 /* Do the single step trick only when coming from userspace */
1523 if (user_mode(regs)) {
1524 current->thread.dbcr0 &= ~DBCR0_BT;
1525 current->thread.dbcr0 |= DBCR0_IDM | DBCR0_IC;
1526 regs->msr |= MSR_DE;
1530 if (notify_die(DIE_SSTEP, "block_step", regs, 5,
1531 5, SIGTRAP) == NOTIFY_STOP) {
1534 if (debugger_sstep(regs))
1536 } else if (debug_status & DBSR_IC) { /* Instruction complete */
1537 regs->msr &= ~MSR_DE;
1539 /* Disable instruction completion */
1540 mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) & ~DBCR0_IC);
1541 /* Clear the instruction completion event */
1542 mtspr(SPRN_DBSR, DBSR_IC);
1544 if (notify_die(DIE_SSTEP, "single_step", regs, 5,
1545 5, SIGTRAP) == NOTIFY_STOP) {
1549 if (debugger_sstep(regs))
1552 if (user_mode(regs)) {
1553 current->thread.dbcr0 &= ~DBCR0_IC;
1554 if (DBCR_ACTIVE_EVENTS(current->thread.dbcr0,
1555 current->thread.dbcr1))
1556 regs->msr |= MSR_DE;
1558 /* Make sure the IDM bit is off */
1559 current->thread.dbcr0 &= ~DBCR0_IDM;
1562 _exception(SIGTRAP, regs, TRAP_TRACE, regs->nip);
1564 handle_debug(regs, debug_status);
1566 #endif /* CONFIG_PPC_ADV_DEBUG_REGS */
1568 #if !defined(CONFIG_TAU_INT)
1569 void TAUException(struct pt_regs *regs)
1571 printk("TAU trap at PC: %lx, MSR: %lx, vector=%lx %s\n",
1572 regs->nip, regs->msr, regs->trap, print_tainted());
1574 #endif /* CONFIG_INT_TAU */
1576 #ifdef CONFIG_ALTIVEC
1577 void altivec_assist_exception(struct pt_regs *regs)
1581 if (!user_mode(regs)) {
1582 printk(KERN_EMERG "VMX/Altivec assist exception in kernel mode"
1583 " at %lx\n", regs->nip);
1584 die("Kernel VMX/Altivec assist exception", regs, SIGILL);
1587 flush_altivec_to_thread(current);
1589 PPC_WARN_EMULATED(altivec, regs);
1590 err = emulate_altivec(regs);
1592 regs->nip += 4; /* skip emulated instruction */
1593 emulate_single_step(regs);
1597 if (err == -EFAULT) {
1598 /* got an error reading the instruction */
1599 _exception(SIGSEGV, regs, SEGV_ACCERR, regs->nip);
1601 /* didn't recognize the instruction */
1602 /* XXX quick hack for now: set the non-Java bit in the VSCR */
1603 printk_ratelimited(KERN_ERR "Unrecognized altivec instruction "
1604 "in %s at %lx\n", current->comm, regs->nip);
1605 current->thread.vscr.u[3] |= 0x10000;
1608 #endif /* CONFIG_ALTIVEC */
1611 void vsx_assist_exception(struct pt_regs *regs)
1613 if (!user_mode(regs)) {
1614 printk(KERN_EMERG "VSX assist exception in kernel mode"
1615 " at %lx\n", regs->nip);
1616 die("Kernel VSX assist exception", regs, SIGILL);
1619 flush_vsx_to_thread(current);
1620 printk(KERN_INFO "VSX assist not supported at %lx\n", regs->nip);
1621 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
1623 #endif /* CONFIG_VSX */
1625 #ifdef CONFIG_FSL_BOOKE
1626 void CacheLockingException(struct pt_regs *regs, unsigned long address,
1627 unsigned long error_code)
1629 /* We treat cache locking instructions from the user
1630 * as priv ops, in the future we could try to do
1633 if (error_code & (ESR_DLK|ESR_ILK))
1634 _exception(SIGILL, regs, ILL_PRVOPC, regs->nip);
1637 #endif /* CONFIG_FSL_BOOKE */
1640 void SPEFloatingPointException(struct pt_regs *regs)
1642 extern int do_spe_mathemu(struct pt_regs *regs);
1643 unsigned long spefscr;
1648 flush_spe_to_thread(current);
1650 spefscr = current->thread.spefscr;
1651 fpexc_mode = current->thread.fpexc_mode;
1653 if ((spefscr & SPEFSCR_FOVF) && (fpexc_mode & PR_FP_EXC_OVF)) {
1656 else if ((spefscr & SPEFSCR_FUNF) && (fpexc_mode & PR_FP_EXC_UND)) {
1659 else if ((spefscr & SPEFSCR_FDBZ) && (fpexc_mode & PR_FP_EXC_DIV))
1661 else if ((spefscr & SPEFSCR_FINV) && (fpexc_mode & PR_FP_EXC_INV)) {
1664 else if ((spefscr & (SPEFSCR_FG | SPEFSCR_FX)) && (fpexc_mode & PR_FP_EXC_RES))
1667 err = do_spe_mathemu(regs);
1669 regs->nip += 4; /* skip emulated instruction */
1670 emulate_single_step(regs);
1674 if (err == -EFAULT) {
1675 /* got an error reading the instruction */
1676 _exception(SIGSEGV, regs, SEGV_ACCERR, regs->nip);
1677 } else if (err == -EINVAL) {
1678 /* didn't recognize the instruction */
1679 printk(KERN_ERR "unrecognized spe instruction "
1680 "in %s at %lx\n", current->comm, regs->nip);
1682 _exception(SIGFPE, regs, code, regs->nip);
1688 void SPEFloatingPointRoundException(struct pt_regs *regs)
1690 extern int speround_handler(struct pt_regs *regs);
1694 if (regs->msr & MSR_SPE)
1695 giveup_spe(current);
1699 err = speround_handler(regs);
1701 regs->nip += 4; /* skip emulated instruction */
1702 emulate_single_step(regs);
1706 if (err == -EFAULT) {
1707 /* got an error reading the instruction */
1708 _exception(SIGSEGV, regs, SEGV_ACCERR, regs->nip);
1709 } else if (err == -EINVAL) {
1710 /* didn't recognize the instruction */
1711 printk(KERN_ERR "unrecognized spe instruction "
1712 "in %s at %lx\n", current->comm, regs->nip);
1714 _exception(SIGFPE, regs, 0, regs->nip);
1721 * We enter here if we get an unrecoverable exception, that is, one
1722 * that happened at a point where the RI (recoverable interrupt) bit
1723 * in the MSR is 0. This indicates that SRR0/1 are live, and that
1724 * we therefore lost state by taking this exception.
1726 void unrecoverable_exception(struct pt_regs *regs)
1728 printk(KERN_EMERG "Unrecoverable exception %lx at %lx\n",
1729 regs->trap, regs->nip);
1730 die("Unrecoverable exception", regs, SIGABRT);
1733 #if defined(CONFIG_BOOKE_WDT) || defined(CONFIG_40x)
1735 * Default handler for a Watchdog exception,
1736 * spins until a reboot occurs
1738 void __attribute__ ((weak)) WatchdogHandler(struct pt_regs *regs)
1740 /* Generic WatchdogHandler, implement your own */
1741 mtspr(SPRN_TCR, mfspr(SPRN_TCR)&(~TCR_WIE));
1745 void WatchdogException(struct pt_regs *regs)
1747 printk (KERN_EMERG "PowerPC Book-E Watchdog Exception\n");
1748 WatchdogHandler(regs);
1753 * We enter here if we discover during exception entry that we are
1754 * running in supervisor mode with a userspace value in the stack pointer.
1756 void kernel_bad_stack(struct pt_regs *regs)
1758 printk(KERN_EMERG "Bad kernel stack pointer %lx at %lx\n",
1759 regs->gpr[1], regs->nip);
1760 die("Bad kernel stack pointer", regs, SIGABRT);
1763 void __init trap_init(void)
1768 #ifdef CONFIG_PPC_EMULATED_STATS
1770 #define WARN_EMULATED_SETUP(type) .type = { .name = #type }
1772 struct ppc_emulated ppc_emulated = {
1773 #ifdef CONFIG_ALTIVEC
1774 WARN_EMULATED_SETUP(altivec),
1776 WARN_EMULATED_SETUP(dcba),
1777 WARN_EMULATED_SETUP(dcbz),
1778 WARN_EMULATED_SETUP(fp_pair),
1779 WARN_EMULATED_SETUP(isel),
1780 WARN_EMULATED_SETUP(mcrxr),
1781 WARN_EMULATED_SETUP(mfpvr),
1782 WARN_EMULATED_SETUP(multiple),
1783 WARN_EMULATED_SETUP(popcntb),
1784 WARN_EMULATED_SETUP(spe),
1785 WARN_EMULATED_SETUP(string),
1786 WARN_EMULATED_SETUP(unaligned),
1787 #ifdef CONFIG_MATH_EMULATION
1788 WARN_EMULATED_SETUP(math),
1789 #elif defined(CONFIG_8XX_MINIMAL_FPEMU)
1790 WARN_EMULATED_SETUP(8xx),
1793 WARN_EMULATED_SETUP(vsx),
1796 WARN_EMULATED_SETUP(mfdscr),
1797 WARN_EMULATED_SETUP(mtdscr),
1801 u32 ppc_warn_emulated;
1803 void ppc_warn_emulated_print(const char *type)
1805 pr_warn_ratelimited("%s used emulated %s instruction\n", current->comm,
1809 static int __init ppc_warn_emulated_init(void)
1811 struct dentry *dir, *d;
1813 struct ppc_emulated_entry *entries = (void *)&ppc_emulated;
1815 if (!powerpc_debugfs_root)
1818 dir = debugfs_create_dir("emulated_instructions",
1819 powerpc_debugfs_root);
1823 d = debugfs_create_u32("do_warn", S_IRUGO | S_IWUSR, dir,
1824 &ppc_warn_emulated);
1828 for (i = 0; i < sizeof(ppc_emulated)/sizeof(*entries); i++) {
1829 d = debugfs_create_u32(entries[i].name, S_IRUGO | S_IWUSR, dir,
1830 (u32 *)&entries[i].val.counter);
1838 debugfs_remove_recursive(dir);
1842 device_initcall(ppc_warn_emulated_init);
1844 #endif /* CONFIG_PPC_EMULATED_STATS */