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1 | /* |
2 | * arch/powerpc/kernel/traps.c | |
3 | * | |
4 | * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | * | |
11 | * Modified by Cort Dougan (cort@cs.nmt.edu) | |
12 | * and Paul Mackerras (paulus@samba.org) | |
13 | */ | |
14 | ||
15 | /* | |
16 | * This file handles the architecture-dependent parts of hardware exceptions | |
17 | */ | |
18 | ||
19 | #include <linux/config.h> | |
20 | #include <linux/errno.h> | |
21 | #include <linux/sched.h> | |
22 | #include <linux/kernel.h> | |
23 | #include <linux/mm.h> | |
24 | #include <linux/stddef.h> | |
25 | #include <linux/unistd.h> | |
26 | #include <linux/ptrace.h> | |
27 | #include <linux/slab.h> | |
28 | #include <linux/user.h> | |
29 | #include <linux/a.out.h> | |
30 | #include <linux/interrupt.h> | |
31 | #include <linux/config.h> | |
32 | #include <linux/init.h> | |
33 | #include <linux/module.h> | |
34 | #include <linux/prctl.h> | |
35 | #include <linux/delay.h> | |
36 | #include <linux/kprobes.h> | |
37 | #include <asm/kdebug.h> | |
38 | ||
39 | #include <asm/pgtable.h> | |
40 | #include <asm/uaccess.h> | |
41 | #include <asm/system.h> | |
42 | #include <asm/io.h> | |
43 | #include <asm/reg.h> | |
44 | #include <asm/xmon.h> | |
45 | #ifdef CONFIG_PMAC_BACKLIGHT | |
46 | #include <asm/backlight.h> | |
47 | #endif | |
48 | #include <asm/perfmon.h> | |
49 | ||
50 | #ifdef CONFIG_DEBUGGER | |
51 | int (*__debugger)(struct pt_regs *regs); | |
52 | int (*__debugger_ipi)(struct pt_regs *regs); | |
53 | int (*__debugger_bpt)(struct pt_regs *regs); | |
54 | int (*__debugger_sstep)(struct pt_regs *regs); | |
55 | int (*__debugger_iabr_match)(struct pt_regs *regs); | |
56 | int (*__debugger_dabr_match)(struct pt_regs *regs); | |
57 | int (*__debugger_fault_handler)(struct pt_regs *regs); | |
58 | ||
59 | EXPORT_SYMBOL(__debugger); | |
60 | EXPORT_SYMBOL(__debugger_ipi); | |
61 | EXPORT_SYMBOL(__debugger_bpt); | |
62 | EXPORT_SYMBOL(__debugger_sstep); | |
63 | EXPORT_SYMBOL(__debugger_iabr_match); | |
64 | EXPORT_SYMBOL(__debugger_dabr_match); | |
65 | EXPORT_SYMBOL(__debugger_fault_handler); | |
66 | #endif | |
67 | ||
68 | struct notifier_block *powerpc_die_chain; | |
69 | static DEFINE_SPINLOCK(die_notifier_lock); | |
70 | ||
71 | int register_die_notifier(struct notifier_block *nb) | |
72 | { | |
73 | int err = 0; | |
74 | unsigned long flags; | |
75 | ||
76 | spin_lock_irqsave(&die_notifier_lock, flags); | |
77 | err = notifier_chain_register(&powerpc_die_chain, nb); | |
78 | spin_unlock_irqrestore(&die_notifier_lock, flags); | |
79 | return err; | |
80 | } | |
81 | ||
82 | /* | |
83 | * Trap & Exception support | |
84 | */ | |
85 | ||
86 | static DEFINE_SPINLOCK(die_lock); | |
87 | ||
88 | int die(const char *str, struct pt_regs *regs, long err) | |
89 | { | |
90 | static int die_counter; | |
91 | int nl = 0; | |
92 | ||
93 | if (debugger(regs)) | |
94 | return 1; | |
95 | ||
96 | console_verbose(); | |
97 | spin_lock_irq(&die_lock); | |
98 | bust_spinlocks(1); | |
99 | #ifdef CONFIG_PMAC_BACKLIGHT | |
100 | if (_machine == _MACH_Pmac) { | |
101 | set_backlight_enable(1); | |
102 | set_backlight_level(BACKLIGHT_MAX); | |
103 | } | |
104 | #endif | |
105 | printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter); | |
106 | #ifdef CONFIG_PREEMPT | |
107 | printk("PREEMPT "); | |
108 | nl = 1; | |
109 | #endif | |
110 | #ifdef CONFIG_SMP | |
111 | printk("SMP NR_CPUS=%d ", NR_CPUS); | |
112 | nl = 1; | |
113 | #endif | |
114 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
115 | printk("DEBUG_PAGEALLOC "); | |
116 | nl = 1; | |
117 | #endif | |
118 | #ifdef CONFIG_NUMA | |
119 | printk("NUMA "); | |
120 | nl = 1; | |
121 | #endif | |
122 | #ifdef CONFIG_PPC64 | |
123 | switch (systemcfg->platform) { | |
124 | case PLATFORM_PSERIES: | |
125 | printk("PSERIES "); | |
126 | nl = 1; | |
127 | break; | |
128 | case PLATFORM_PSERIES_LPAR: | |
129 | printk("PSERIES LPAR "); | |
130 | nl = 1; | |
131 | break; | |
132 | case PLATFORM_ISERIES_LPAR: | |
133 | printk("ISERIES LPAR "); | |
134 | nl = 1; | |
135 | break; | |
136 | case PLATFORM_POWERMAC: | |
137 | printk("POWERMAC "); | |
138 | nl = 1; | |
139 | break; | |
140 | case PLATFORM_BPA: | |
141 | printk("BPA "); | |
142 | nl = 1; | |
143 | break; | |
144 | } | |
145 | #endif | |
146 | if (nl) | |
147 | printk("\n"); | |
148 | print_modules(); | |
149 | show_regs(regs); | |
150 | bust_spinlocks(0); | |
151 | spin_unlock_irq(&die_lock); | |
152 | ||
153 | if (in_interrupt()) | |
154 | panic("Fatal exception in interrupt"); | |
155 | ||
156 | if (panic_on_oops) { | |
157 | panic("Fatal exception"); | |
158 | } | |
159 | do_exit(err); | |
160 | ||
161 | return 0; | |
162 | } | |
163 | ||
164 | void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr) | |
165 | { | |
166 | siginfo_t info; | |
167 | ||
168 | if (!user_mode(regs)) { | |
169 | if (die("Exception in kernel mode", regs, signr)) | |
170 | return; | |
171 | } | |
172 | ||
173 | memset(&info, 0, sizeof(info)); | |
174 | info.si_signo = signr; | |
175 | info.si_code = code; | |
176 | info.si_addr = (void __user *) addr; | |
177 | force_sig_info(signr, &info, current); | |
178 | ||
179 | /* | |
180 | * Init gets no signals that it doesn't have a handler for. | |
181 | * That's all very well, but if it has caused a synchronous | |
182 | * exception and we ignore the resulting signal, it will just | |
183 | * generate the same exception over and over again and we get | |
184 | * nowhere. Better to kill it and let the kernel panic. | |
185 | */ | |
186 | if (current->pid == 1) { | |
187 | __sighandler_t handler; | |
188 | ||
189 | spin_lock_irq(¤t->sighand->siglock); | |
190 | handler = current->sighand->action[signr-1].sa.sa_handler; | |
191 | spin_unlock_irq(¤t->sighand->siglock); | |
192 | if (handler == SIG_DFL) { | |
193 | /* init has generated a synchronous exception | |
194 | and it doesn't have a handler for the signal */ | |
195 | printk(KERN_CRIT "init has generated signal %d " | |
196 | "but has no handler for it\n", signr); | |
197 | do_exit(signr); | |
198 | } | |
199 | } | |
200 | } | |
201 | ||
202 | #ifdef CONFIG_PPC64 | |
203 | void system_reset_exception(struct pt_regs *regs) | |
204 | { | |
205 | /* See if any machine dependent calls */ | |
206 | if (ppc_md.system_reset_exception) | |
207 | ppc_md.system_reset_exception(regs); | |
208 | ||
209 | die("System Reset", regs, SIGABRT); | |
210 | ||
211 | /* Must die if the interrupt is not recoverable */ | |
212 | if (!(regs->msr & MSR_RI)) | |
213 | panic("Unrecoverable System Reset"); | |
214 | ||
215 | /* What should we do here? We could issue a shutdown or hard reset. */ | |
216 | } | |
217 | #endif | |
218 | ||
219 | /* | |
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 | |
223 | * table. | |
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. | |
227 | * -- paulus. | |
228 | */ | |
229 | static inline int check_io_access(struct pt_regs *regs) | |
230 | { | |
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; | |
235 | ||
236 | if (((msr & 0xffff0000) == 0 || (msr & (0x80000 | 0x40000))) | |
237 | && (entry = search_exception_tables(regs->nip)) != NULL) { | |
238 | /* | |
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 | |
244 | * load or store. | |
245 | */ | |
246 | if (*nip == 0x60000000) /* nop */ | |
247 | nip -= 2; | |
248 | else if (*nip == 0x4c00012c) /* isync */ | |
249 | --nip; | |
250 | if (*nip == 0x7c0004ac || (*nip >> 26) == 3) { | |
251 | /* sync or twi */ | |
252 | unsigned int rb; | |
253 | ||
254 | --nip; | |
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); | |
259 | regs->msr |= MSR_RI; | |
260 | regs->nip = entry->fixup; | |
261 | return 1; | |
262 | } | |
263 | } | |
264 | #endif /* CONFIG_PPC_PMAC */ | |
265 | return 0; | |
266 | } | |
267 | ||
268 | #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE) | |
269 | /* On 4xx, the reason for the machine check or program exception | |
270 | is in the ESR. */ | |
271 | #define get_reason(regs) ((regs)->dsisr) | |
272 | #ifndef CONFIG_FSL_BOOKE | |
273 | #define get_mc_reason(regs) ((regs)->dsisr) | |
274 | #else | |
275 | #define get_mc_reason(regs) (mfspr(SPRN_MCSR)) | |
276 | #endif | |
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 | |
281 | ||
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) | |
285 | ||
286 | #else | |
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 | |
295 | ||
296 | #define single_stepping(regs) ((regs)->msr & MSR_SE) | |
297 | #define clear_single_step(regs) ((regs)->msr &= ~MSR_SE) | |
298 | #endif | |
299 | ||
300 | /* | |
301 | * This is "fall-back" implementation for configurations | |
302 | * which don't provide platform-specific machine check info | |
303 | */ | |
304 | void __attribute__ ((weak)) | |
305 | platform_machine_check(struct pt_regs *regs) | |
306 | { | |
307 | } | |
308 | ||
309 | void MachineCheckException(struct pt_regs *regs) | |
310 | { | |
311 | #ifdef CONFIG_PPC64 | |
312 | int recover = 0; | |
313 | ||
314 | /* See if any machine dependent calls */ | |
315 | if (ppc_md.machine_check_exception) | |
316 | recover = ppc_md.machine_check_exception(regs); | |
317 | ||
318 | if (recover) | |
319 | return; | |
320 | #else | |
321 | unsigned long reason = get_mc_reason(regs); | |
322 | ||
323 | if (user_mode(regs)) { | |
324 | regs->msr |= MSR_RI; | |
325 | _exception(SIGBUS, regs, BUS_ADRERR, regs->nip); | |
326 | return; | |
327 | } | |
328 | ||
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); | |
332 | return; | |
333 | #endif | |
334 | ||
335 | if (debugger_fault_handler(regs)) { | |
336 | regs->msr |= MSR_RI; | |
337 | return; | |
338 | } | |
339 | ||
340 | if (check_io_access(regs)) | |
341 | return; | |
342 | ||
343 | #if defined(CONFIG_4xx) && !defined(CONFIG_440A) | |
344 | if (reason & ESR_IMCP) { | |
345 | printk("Instruction"); | |
346 | mtspr(SPRN_ESR, reason & ~ESR_IMCP); | |
347 | } else | |
348 | printk("Data"); | |
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); | |
355 | } | |
356 | else { | |
357 | u32 mcsr = mfspr(SPRN_MCSR); | |
358 | if (mcsr & MCSR_IB) | |
359 | printk("Instruction Read PLB Error\n"); | |
360 | if (mcsr & MCSR_DRB) | |
361 | printk("Data Read PLB Error\n"); | |
362 | if (mcsr & MCSR_DWB) | |
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"); | |
369 | } | |
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"); | |
376 | ||
377 | /* Clear MCSR */ | |
378 | mtspr(SPRN_MCSR, mcsr); | |
379 | } | |
380 | #elif defined (CONFIG_E500) | |
381 | printk("Machine check in kernel mode.\n"); | |
382 | printk("Caused by (from MCSR=%lx): ", reason); | |
383 | ||
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); | |
413 | ||
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) { | |
432 | case 0x80000: | |
433 | printk("Machine check signal\n"); | |
434 | break; | |
435 | case 0: /* for 601 */ | |
436 | case 0x40000: | |
437 | case 0x140000: /* 7450 MSS error and TEA */ | |
438 | printk("Transfer error ack signal\n"); | |
439 | break; | |
440 | case 0x20000: | |
441 | printk("Data parity error signal\n"); | |
442 | break; | |
443 | case 0x10000: | |
444 | printk("Address parity error signal\n"); | |
445 | break; | |
446 | case 0x20000000: | |
447 | printk("L1 Data Cache error\n"); | |
448 | break; | |
449 | case 0x40000000: | |
450 | printk("L1 Instruction Cache error\n"); | |
451 | break; | |
452 | case 0x00100000: | |
453 | printk("L2 data cache parity error\n"); | |
454 | break; | |
455 | default: | |
456 | printk("Unknown values in msr\n"); | |
457 | } | |
458 | #endif /* CONFIG_4xx */ | |
459 | ||
460 | /* | |
461 | * Optional platform-provided routine to print out | |
462 | * additional info, e.g. bus error registers. | |
463 | */ | |
464 | platform_machine_check(regs); | |
465 | #endif /* CONFIG_PPC64 */ | |
466 | ||
467 | if (debugger_fault_handler(regs)) | |
468 | return; | |
469 | die("Machine check", regs, SIGBUS); | |
470 | ||
471 | /* Must die if the interrupt is not recoverable */ | |
472 | if (!(regs->msr & MSR_RI)) | |
473 | panic("Unrecoverable Machine check"); | |
474 | } | |
475 | ||
476 | void SMIException(struct pt_regs *regs) | |
477 | { | |
478 | die("System Management Interrupt", regs, SIGABRT); | |
479 | } | |
480 | ||
481 | void UnknownException(struct pt_regs *regs) | |
482 | { | |
483 | printk("Bad trap at PC: %lx, SR: %lx, vector=%lx\n", | |
484 | regs->nip, regs->msr, regs->trap); | |
485 | ||
486 | _exception(SIGTRAP, regs, 0, 0); | |
487 | } | |
488 | ||
489 | void InstructionBreakpoint(struct pt_regs *regs) | |
490 | { | |
491 | if (notify_die(DIE_IABR_MATCH, "iabr_match", regs, 5, | |
492 | 5, SIGTRAP) == NOTIFY_STOP) | |
493 | return; | |
494 | if (debugger_iabr_match(regs)) | |
495 | return; | |
496 | _exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip); | |
497 | } | |
498 | ||
499 | void RunModeException(struct pt_regs *regs) | |
500 | { | |
501 | _exception(SIGTRAP, regs, 0, 0); | |
502 | } | |
503 | ||
504 | void SingleStepException(struct pt_regs *regs) | |
505 | { | |
506 | regs->msr &= ~(MSR_SE | MSR_BE); /* Turn off 'trace' bits */ | |
507 | ||
508 | if (notify_die(DIE_SSTEP, "single_step", regs, 5, | |
509 | 5, SIGTRAP) == NOTIFY_STOP) | |
510 | return; | |
511 | if (debugger_sstep(regs)) | |
512 | return; | |
513 | ||
514 | _exception(SIGTRAP, regs, TRAP_TRACE, regs->nip); | |
515 | } | |
516 | ||
517 | /* | |
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 | |
522 | */ | |
523 | static void emulate_single_step(struct pt_regs *regs) | |
524 | { | |
525 | if (single_stepping(regs)) { | |
526 | clear_single_step(regs); | |
527 | _exception(SIGTRAP, regs, TRAP_TRACE, 0); | |
528 | } | |
529 | } | |
530 | ||
531 | /* Illegal instruction emulation support. Originally written to | |
532 | * provide the PVR to user applications using the mfspr rd, PVR. | |
533 | * Return non-zero if we can't emulate, or -EFAULT if the associated | |
534 | * memory access caused an access fault. Return zero on success. | |
535 | * | |
536 | * There are a couple of ways to do this, either "decode" the instruction | |
537 | * or directly match lots of bits. In this case, matching lots of | |
538 | * bits is faster and easier. | |
539 | * | |
540 | */ | |
541 | #define INST_MFSPR_PVR 0x7c1f42a6 | |
542 | #define INST_MFSPR_PVR_MASK 0xfc1fffff | |
543 | ||
544 | #define INST_DCBA 0x7c0005ec | |
545 | #define INST_DCBA_MASK 0x7c0007fe | |
546 | ||
547 | #define INST_MCRXR 0x7c000400 | |
548 | #define INST_MCRXR_MASK 0x7c0007fe | |
549 | ||
550 | #define INST_STRING 0x7c00042a | |
551 | #define INST_STRING_MASK 0x7c0007fe | |
552 | #define INST_STRING_GEN_MASK 0x7c00067e | |
553 | #define INST_LSWI 0x7c0004aa | |
554 | #define INST_LSWX 0x7c00042a | |
555 | #define INST_STSWI 0x7c0005aa | |
556 | #define INST_STSWX 0x7c00052a | |
557 | ||
558 | static int emulate_string_inst(struct pt_regs *regs, u32 instword) | |
559 | { | |
560 | u8 rT = (instword >> 21) & 0x1f; | |
561 | u8 rA = (instword >> 16) & 0x1f; | |
562 | u8 NB_RB = (instword >> 11) & 0x1f; | |
563 | u32 num_bytes; | |
564 | unsigned long EA; | |
565 | int pos = 0; | |
566 | ||
567 | /* Early out if we are an invalid form of lswx */ | |
568 | if ((instword & INST_STRING_MASK) == INST_LSWX) | |
569 | if ((rT == rA) || (rT == NB_RB)) | |
570 | return -EINVAL; | |
571 | ||
572 | EA = (rA == 0) ? 0 : regs->gpr[rA]; | |
573 | ||
574 | switch (instword & INST_STRING_MASK) { | |
575 | case INST_LSWX: | |
576 | case INST_STSWX: | |
577 | EA += NB_RB; | |
578 | num_bytes = regs->xer & 0x7f; | |
579 | break; | |
580 | case INST_LSWI: | |
581 | case INST_STSWI: | |
582 | num_bytes = (NB_RB == 0) ? 32 : NB_RB; | |
583 | break; | |
584 | default: | |
585 | return -EINVAL; | |
586 | } | |
587 | ||
588 | while (num_bytes != 0) | |
589 | { | |
590 | u8 val; | |
591 | u32 shift = 8 * (3 - (pos & 0x3)); | |
592 | ||
593 | switch ((instword & INST_STRING_MASK)) { | |
594 | case INST_LSWX: | |
595 | case INST_LSWI: | |
596 | if (get_user(val, (u8 __user *)EA)) | |
597 | return -EFAULT; | |
598 | /* first time updating this reg, | |
599 | * zero it out */ | |
600 | if (pos == 0) | |
601 | regs->gpr[rT] = 0; | |
602 | regs->gpr[rT] |= val << shift; | |
603 | break; | |
604 | case INST_STSWI: | |
605 | case INST_STSWX: | |
606 | val = regs->gpr[rT] >> shift; | |
607 | if (put_user(val, (u8 __user *)EA)) | |
608 | return -EFAULT; | |
609 | break; | |
610 | } | |
611 | /* move EA to next address */ | |
612 | EA += 1; | |
613 | num_bytes--; | |
614 | ||
615 | /* manage our position within the register */ | |
616 | if (++pos == 4) { | |
617 | pos = 0; | |
618 | if (++rT == 32) | |
619 | rT = 0; | |
620 | } | |
621 | } | |
622 | ||
623 | return 0; | |
624 | } | |
625 | ||
626 | static int emulate_instruction(struct pt_regs *regs) | |
627 | { | |
628 | u32 instword; | |
629 | u32 rd; | |
630 | ||
631 | if (!user_mode(regs)) | |
632 | return -EINVAL; | |
633 | CHECK_FULL_REGS(regs); | |
634 | ||
635 | if (get_user(instword, (u32 __user *)(regs->nip))) | |
636 | return -EFAULT; | |
637 | ||
638 | /* Emulate the mfspr rD, PVR. */ | |
639 | if ((instword & INST_MFSPR_PVR_MASK) == INST_MFSPR_PVR) { | |
640 | rd = (instword >> 21) & 0x1f; | |
641 | regs->gpr[rd] = mfspr(SPRN_PVR); | |
642 | return 0; | |
643 | } | |
644 | ||
645 | /* Emulating the dcba insn is just a no-op. */ | |
646 | if ((instword & INST_DCBA_MASK) == INST_DCBA) | |
647 | return 0; | |
648 | ||
649 | /* Emulate the mcrxr insn. */ | |
650 | if ((instword & INST_MCRXR_MASK) == INST_MCRXR) { | |
651 | int shift = (instword >> 21) & 0x1c; | |
652 | unsigned long msk = 0xf0000000UL >> shift; | |
653 | ||
654 | regs->ccr = (regs->ccr & ~msk) | ((regs->xer >> shift) & msk); | |
655 | regs->xer &= ~0xf0000000UL; | |
656 | return 0; | |
657 | } | |
658 | ||
659 | /* Emulate load/store string insn. */ | |
660 | if ((instword & INST_STRING_GEN_MASK) == INST_STRING) | |
661 | return emulate_string_inst(regs, instword); | |
662 | ||
663 | return -EINVAL; | |
664 | } | |
665 | ||
666 | /* | |
667 | * Look through the list of trap instructions that are used for BUG(), | |
668 | * BUG_ON() and WARN_ON() and see if we hit one. At this point we know | |
669 | * that the exception was caused by a trap instruction of some kind. | |
670 | * Returns 1 if we should continue (i.e. it was a WARN_ON) or 0 | |
671 | * otherwise. | |
672 | */ | |
673 | extern struct bug_entry __start___bug_table[], __stop___bug_table[]; | |
674 | ||
675 | #ifndef CONFIG_MODULES | |
676 | #define module_find_bug(x) NULL | |
677 | #endif | |
678 | ||
679 | struct bug_entry *find_bug(unsigned long bugaddr) | |
680 | { | |
681 | struct bug_entry *bug; | |
682 | ||
683 | for (bug = __start___bug_table; bug < __stop___bug_table; ++bug) | |
684 | if (bugaddr == bug->bug_addr) | |
685 | return bug; | |
686 | return module_find_bug(bugaddr); | |
687 | } | |
688 | ||
689 | int check_bug_trap(struct pt_regs *regs) | |
690 | { | |
691 | struct bug_entry *bug; | |
692 | unsigned long addr; | |
693 | ||
694 | if (regs->msr & MSR_PR) | |
695 | return 0; /* not in kernel */ | |
696 | addr = regs->nip; /* address of trap instruction */ | |
697 | if (addr < PAGE_OFFSET) | |
698 | return 0; | |
699 | bug = find_bug(regs->nip); | |
700 | if (bug == NULL) | |
701 | return 0; | |
702 | if (bug->line & BUG_WARNING_TRAP) { | |
703 | /* this is a WARN_ON rather than BUG/BUG_ON */ | |
704 | #ifdef CONFIG_XMON | |
705 | xmon_printf(KERN_ERR "Badness in %s at %s:%d\n", | |
706 | bug->function, bug->file, | |
707 | bug->line & ~BUG_WARNING_TRAP); | |
708 | #endif /* CONFIG_XMON */ | |
709 | printk(KERN_ERR "Badness in %s at %s:%d\n", | |
710 | bug->function, bug->file, | |
711 | bug->line & ~BUG_WARNING_TRAP); | |
712 | dump_stack(); | |
713 | return 1; | |
714 | } | |
715 | #ifdef CONFIG_XMON | |
716 | xmon_printf(KERN_CRIT "kernel BUG in %s at %s:%d!\n", | |
717 | bug->function, bug->file, bug->line); | |
718 | xmon(regs); | |
719 | #endif /* CONFIG_XMON */ | |
720 | printk(KERN_CRIT "kernel BUG in %s at %s:%d!\n", | |
721 | bug->function, bug->file, bug->line); | |
722 | ||
723 | return 0; | |
724 | } | |
725 | ||
726 | void ProgramCheckException(struct pt_regs *regs) | |
727 | { | |
728 | unsigned int reason = get_reason(regs); | |
729 | extern int do_mathemu(struct pt_regs *regs); | |
730 | ||
731 | #ifdef CONFIG_MATH_EMULATION | |
732 | /* (reason & REASON_ILLEGAL) would be the obvious thing here, | |
733 | * but there seems to be a hardware bug on the 405GP (RevD) | |
734 | * that means ESR is sometimes set incorrectly - either to | |
735 | * ESR_DST (!?) or 0. In the process of chasing this with the | |
736 | * hardware people - not sure if it can happen on any illegal | |
737 | * instruction or only on FP instructions, whether there is a | |
738 | * pattern to occurences etc. -dgibson 31/Mar/2003 */ | |
739 | if (!(reason & REASON_TRAP) && do_mathemu(regs) == 0) { | |
740 | emulate_single_step(regs); | |
741 | return; | |
742 | } | |
743 | #endif /* CONFIG_MATH_EMULATION */ | |
744 | ||
745 | if (reason & REASON_FP) { | |
746 | /* IEEE FP exception */ | |
747 | int code = 0; | |
748 | u32 fpscr; | |
749 | ||
750 | /* We must make sure the FP state is consistent with | |
751 | * our MSR_FP in regs | |
752 | */ | |
753 | preempt_disable(); | |
754 | if (regs->msr & MSR_FP) | |
755 | giveup_fpu(current); | |
756 | preempt_enable(); | |
757 | ||
758 | fpscr = current->thread.fpscr; | |
759 | fpscr &= fpscr << 22; /* mask summary bits with enables */ | |
760 | if (fpscr & FPSCR_VX) | |
761 | code = FPE_FLTINV; | |
762 | else if (fpscr & FPSCR_OX) | |
763 | code = FPE_FLTOVF; | |
764 | else if (fpscr & FPSCR_UX) | |
765 | code = FPE_FLTUND; | |
766 | else if (fpscr & FPSCR_ZX) | |
767 | code = FPE_FLTDIV; | |
768 | else if (fpscr & FPSCR_XX) | |
769 | code = FPE_FLTRES; | |
770 | _exception(SIGFPE, regs, code, regs->nip); | |
771 | return; | |
772 | } | |
773 | ||
774 | if (reason & REASON_TRAP) { | |
775 | /* trap exception */ | |
776 | if (debugger_bpt(regs)) | |
777 | return; | |
778 | if (check_bug_trap(regs)) { | |
779 | regs->nip += 4; | |
780 | return; | |
781 | } | |
782 | _exception(SIGTRAP, regs, TRAP_BRKPT, 0); | |
783 | return; | |
784 | } | |
785 | ||
786 | /* Try to emulate it if we should. */ | |
787 | if (reason & (REASON_ILLEGAL | REASON_PRIVILEGED)) { | |
788 | switch (emulate_instruction(regs)) { | |
789 | case 0: | |
790 | regs->nip += 4; | |
791 | emulate_single_step(regs); | |
792 | return; | |
793 | case -EFAULT: | |
794 | _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip); | |
795 | return; | |
796 | } | |
797 | } | |
798 | ||
799 | if (reason & REASON_PRIVILEGED) | |
800 | _exception(SIGILL, regs, ILL_PRVOPC, regs->nip); | |
801 | else | |
802 | _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); | |
803 | } | |
804 | ||
805 | void AlignmentException(struct pt_regs *regs) | |
806 | { | |
807 | int fixed; | |
808 | ||
809 | fixed = fix_alignment(regs); | |
810 | ||
811 | if (fixed == 1) { | |
812 | regs->nip += 4; /* skip over emulated instruction */ | |
813 | emulate_single_step(regs); | |
814 | return; | |
815 | } | |
816 | ||
817 | /* Operand address was bad */ | |
818 | if (fixed == -EFAULT) { | |
819 | if (user_mode(regs)) | |
820 | _exception(SIGSEGV, regs, SEGV_ACCERR, regs->dar); | |
821 | else | |
822 | /* Search exception table */ | |
823 | bad_page_fault(regs, regs->dar, SIGSEGV); | |
824 | return; | |
825 | } | |
826 | _exception(SIGBUS, regs, BUS_ADRALN, regs->dar); | |
827 | } | |
828 | ||
829 | void StackOverflow(struct pt_regs *regs) | |
830 | { | |
831 | printk(KERN_CRIT "Kernel stack overflow in process %p, r1=%lx\n", | |
832 | current, regs->gpr[1]); | |
833 | debugger(regs); | |
834 | show_regs(regs); | |
835 | panic("kernel stack overflow"); | |
836 | } | |
837 | ||
838 | void nonrecoverable_exception(struct pt_regs *regs) | |
839 | { | |
840 | printk(KERN_ERR "Non-recoverable exception at PC=%lx MSR=%lx\n", | |
841 | regs->nip, regs->msr); | |
842 | debugger(regs); | |
843 | die("nonrecoverable exception", regs, SIGKILL); | |
844 | } | |
845 | ||
846 | void trace_syscall(struct pt_regs *regs) | |
847 | { | |
848 | printk("Task: %p(%d), PC: %08lX/%08lX, Syscall: %3ld, Result: %s%ld %s\n", | |
849 | current, current->pid, regs->nip, regs->link, regs->gpr[0], | |
850 | regs->ccr&0x10000000?"Error=":"", regs->gpr[3], print_tainted()); | |
851 | } | |
852 | ||
853 | #ifdef CONFIG_8xx | |
854 | void SoftwareEmulation(struct pt_regs *regs) | |
855 | { | |
856 | extern int do_mathemu(struct pt_regs *); | |
857 | extern int Soft_emulate_8xx(struct pt_regs *); | |
858 | int errcode; | |
859 | ||
860 | CHECK_FULL_REGS(regs); | |
861 | ||
862 | if (!user_mode(regs)) { | |
863 | debugger(regs); | |
864 | die("Kernel Mode Software FPU Emulation", regs, SIGFPE); | |
865 | } | |
866 | ||
867 | #ifdef CONFIG_MATH_EMULATION | |
868 | errcode = do_mathemu(regs); | |
869 | #else | |
870 | errcode = Soft_emulate_8xx(regs); | |
871 | #endif | |
872 | if (errcode) { | |
873 | if (errcode > 0) | |
874 | _exception(SIGFPE, regs, 0, 0); | |
875 | else if (errcode == -EFAULT) | |
876 | _exception(SIGSEGV, regs, 0, 0); | |
877 | else | |
878 | _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); | |
879 | } else | |
880 | emulate_single_step(regs); | |
881 | } | |
882 | #endif /* CONFIG_8xx */ | |
883 | ||
884 | #if defined(CONFIG_40x) || defined(CONFIG_BOOKE) | |
885 | ||
886 | void DebugException(struct pt_regs *regs, unsigned long debug_status) | |
887 | { | |
888 | if (debug_status & DBSR_IC) { /* instruction completion */ | |
889 | regs->msr &= ~MSR_DE; | |
890 | if (user_mode(regs)) { | |
891 | current->thread.dbcr0 &= ~DBCR0_IC; | |
892 | } else { | |
893 | /* Disable instruction completion */ | |
894 | mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) & ~DBCR0_IC); | |
895 | /* Clear the instruction completion event */ | |
896 | mtspr(SPRN_DBSR, DBSR_IC); | |
897 | if (debugger_sstep(regs)) | |
898 | return; | |
899 | } | |
900 | _exception(SIGTRAP, regs, TRAP_TRACE, 0); | |
901 | } | |
902 | } | |
903 | #endif /* CONFIG_4xx || CONFIG_BOOKE */ | |
904 | ||
905 | #if !defined(CONFIG_TAU_INT) | |
906 | void TAUException(struct pt_regs *regs) | |
907 | { | |
908 | printk("TAU trap at PC: %lx, MSR: %lx, vector=%lx %s\n", | |
909 | regs->nip, regs->msr, regs->trap, print_tainted()); | |
910 | } | |
911 | #endif /* CONFIG_INT_TAU */ | |
912 | ||
913 | void AltivecUnavailException(struct pt_regs *regs) | |
914 | { | |
915 | static int kernel_altivec_count; | |
916 | ||
917 | #ifndef CONFIG_ALTIVEC | |
918 | if (user_mode(regs)) { | |
919 | /* A user program has executed an altivec instruction, | |
920 | but this kernel doesn't support altivec. */ | |
921 | _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); | |
922 | return; | |
923 | } | |
924 | #endif | |
925 | /* The kernel has executed an altivec instruction without | |
926 | first enabling altivec. Whinge but let it do it. */ | |
927 | if (++kernel_altivec_count < 10) | |
928 | printk(KERN_ERR "AltiVec used in kernel (task=%p, pc=%lx)\n", | |
929 | current, regs->nip); | |
930 | regs->msr |= MSR_VEC; | |
931 | } | |
932 | ||
933 | #ifdef CONFIG_ALTIVEC | |
934 | void AltivecAssistException(struct pt_regs *regs) | |
935 | { | |
936 | int err; | |
937 | ||
938 | preempt_disable(); | |
939 | if (regs->msr & MSR_VEC) | |
940 | giveup_altivec(current); | |
941 | preempt_enable(); | |
942 | if (!user_mode(regs)) { | |
943 | printk(KERN_EMERG "VMX/Altivec assist exception in kernel mode" | |
944 | " at %lx\n", regs->nip); | |
945 | die("Kernel Altivec assist exception", regs, SIGILL); | |
946 | } | |
947 | ||
948 | err = emulate_altivec(regs); | |
949 | if (err == 0) { | |
950 | regs->nip += 4; /* skip emulated instruction */ | |
951 | emulate_single_step(regs); | |
952 | return; | |
953 | } | |
954 | ||
955 | if (err == -EFAULT) { | |
956 | /* got an error reading the instruction */ | |
957 | _exception(SIGSEGV, regs, SEGV_ACCERR, regs->nip); | |
958 | } else { | |
959 | /* didn't recognize the instruction */ | |
960 | /* XXX quick hack for now: set the non-Java bit in the VSCR */ | |
961 | if (printk_ratelimit()) | |
962 | printk(KERN_ERR "Unrecognized altivec instruction " | |
963 | "in %s at %lx\n", current->comm, regs->nip); | |
964 | current->thread.vscr.u[3] |= 0x10000; | |
965 | } | |
966 | } | |
967 | #endif /* CONFIG_ALTIVEC */ | |
968 | ||
969 | #ifdef CONFIG_E500 | |
970 | void PerformanceMonitorException(struct pt_regs *regs) | |
971 | { | |
972 | perf_irq(regs); | |
973 | } | |
974 | #endif | |
975 | ||
976 | #ifdef CONFIG_FSL_BOOKE | |
977 | void CacheLockingException(struct pt_regs *regs, unsigned long address, | |
978 | unsigned long error_code) | |
979 | { | |
980 | /* We treat cache locking instructions from the user | |
981 | * as priv ops, in the future we could try to do | |
982 | * something smarter | |
983 | */ | |
984 | if (error_code & (ESR_DLK|ESR_ILK)) | |
985 | _exception(SIGILL, regs, ILL_PRVOPC, regs->nip); | |
986 | return; | |
987 | } | |
988 | #endif /* CONFIG_FSL_BOOKE */ | |
989 | ||
990 | #ifdef CONFIG_SPE | |
991 | void SPEFloatingPointException(struct pt_regs *regs) | |
992 | { | |
993 | unsigned long spefscr; | |
994 | int fpexc_mode; | |
995 | int code = 0; | |
996 | ||
997 | spefscr = current->thread.spefscr; | |
998 | fpexc_mode = current->thread.fpexc_mode; | |
999 | ||
1000 | /* Hardware does not neccessarily set sticky | |
1001 | * underflow/overflow/invalid flags */ | |
1002 | if ((spefscr & SPEFSCR_FOVF) && (fpexc_mode & PR_FP_EXC_OVF)) { | |
1003 | code = FPE_FLTOVF; | |
1004 | spefscr |= SPEFSCR_FOVFS; | |
1005 | } | |
1006 | else if ((spefscr & SPEFSCR_FUNF) && (fpexc_mode & PR_FP_EXC_UND)) { | |
1007 | code = FPE_FLTUND; | |
1008 | spefscr |= SPEFSCR_FUNFS; | |
1009 | } | |
1010 | else if ((spefscr & SPEFSCR_FDBZ) && (fpexc_mode & PR_FP_EXC_DIV)) | |
1011 | code = FPE_FLTDIV; | |
1012 | else if ((spefscr & SPEFSCR_FINV) && (fpexc_mode & PR_FP_EXC_INV)) { | |
1013 | code = FPE_FLTINV; | |
1014 | spefscr |= SPEFSCR_FINVS; | |
1015 | } | |
1016 | else if ((spefscr & (SPEFSCR_FG | SPEFSCR_FX)) && (fpexc_mode & PR_FP_EXC_RES)) | |
1017 | code = FPE_FLTRES; | |
1018 | ||
1019 | current->thread.spefscr = spefscr; | |
1020 | ||
1021 | _exception(SIGFPE, regs, code, regs->nip); | |
1022 | return; | |
1023 | } | |
1024 | #endif | |
1025 | ||
1026 | #ifdef CONFIG_BOOKE_WDT | |
1027 | /* | |
1028 | * Default handler for a Watchdog exception, | |
1029 | * spins until a reboot occurs | |
1030 | */ | |
1031 | void __attribute__ ((weak)) WatchdogHandler(struct pt_regs *regs) | |
1032 | { | |
1033 | /* Generic WatchdogHandler, implement your own */ | |
1034 | mtspr(SPRN_TCR, mfspr(SPRN_TCR)&(~TCR_WIE)); | |
1035 | return; | |
1036 | } | |
1037 | ||
1038 | void WatchdogException(struct pt_regs *regs) | |
1039 | { | |
1040 | printk (KERN_EMERG "PowerPC Book-E Watchdog Exception\n"); | |
1041 | WatchdogHandler(regs); | |
1042 | } | |
1043 | #endif | |
1044 | ||
1045 | void __init trap_init(void) | |
1046 | { | |
1047 | } |