xref: /netbsd-src/sys/arch/powerpc/booke/trap.c (revision daf6c4152fcddc27c445489775ed1f66ab4ea9a9)
1 /*	$NetBSD: trap.c,v 1.5 2011/02/17 13:53:32 matt Exp $	*/
2 /*-
3  * Copyright (c) 2010, 2011 The NetBSD Foundation, Inc.
4  * All rights reserved.
5  *
6  * This code is derived from software contributed to The NetBSD Foundation
7  * by Raytheon BBN Technologies Corp and Defense Advanced Research Projects
8  * Agency and which was developed by Matt Thomas of 3am Software Foundry.
9  *
10  * This material is based upon work supported by the Defense Advanced Research
11  * Projects Agency and Space and Naval Warfare Systems Center, Pacific, under
12  * Contract No. N66001-09-C-2073.
13  * Approved for Public Release, Distribution Unlimited
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
25  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
26  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
27  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
28  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34  * POSSIBILITY OF SUCH DAMAGE.
35  */
36 
37 #include "opt_ddb.h"
38 #include "opt_sa.h"
39 
40 #include <sys/cdefs.h>
41 
42 __KERNEL_RCSID(1, "$NetBSD: trap.c,v 1.5 2011/02/17 13:53:32 matt Exp $");
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/siginfo.h>
47 #include <sys/lwp.h>
48 #include <sys/proc.h>
49 #include <sys/cpu.h>
50 #ifdef KERN_SA
51 #include <sys/savar.h>
52 #endif
53 #include <sys/kauth.h>
54 #include <sys/kmem.h>
55 #include <sys/ras.h>
56 
57 #include <uvm/uvm_extern.h>
58 
59 #include <powerpc/pcb.h>
60 #include <powerpc/userret.h>
61 #include <powerpc/psl.h>
62 #include <powerpc/instr.h>
63 #include <powerpc/altivec.h>		/* use same interface for SPE */
64 
65 #include <powerpc/spr.h>
66 #include <powerpc/booke/spr.h>
67 #include <powerpc/booke/cpuvar.h>
68 
69 #include <powerpc/db_machdep.h>
70 #include <ddb/db_interface.h>
71 
72 #include <powerpc/trap.h>
73 #include <powerpc/booke/trap.h>
74 #include <powerpc/booke/pte.h>
75 
76 void trap(enum ppc_booke_exceptions, struct trapframe *);
77 static void dump_trapframe(const struct trapframe *);
78 
79 static const char trap_names[][8] = {
80 	[T_CRITIAL_INPUT] = "CRIT",
81 	[T_EXTERNAL_INPUT] = "EXT",
82 	[T_DECREMENTER] = "DECR",
83 	[T_FIXED_INTERVAL] = "FIT",
84 	[T_WATCHDOG] = "WDOG",
85 	[T_SYSTEM_CALL] = "SC",
86 	[T_MACHINE_CHECK] = "MCHK",
87 	[T_DSI] = "DSI",
88 	[T_ISI] = "ISI",
89 	[T_ALIGNMENT] = "ALN",
90 	[T_PROGRAM] = "PGM",
91 	[T_FP_UNAVAILABLE] = "FP",
92 	[T_AP_UNAVAILABLE] = "AP",
93 	[T_DATA_TLB_ERROR] = "DTLB",
94 	[T_INSTRUCTION_TLB_ERROR] = "ITLB",
95 	[T_DEBUG] = "DEBUG",
96 	[T_SPE_UNAVAILABLE] = "SPE",
97 	[T_EMBEDDED_FP_DATA] = "FPDATA",
98 	[T_EMBEDDED_FP_ROUND] = "FPROUND",
99 	[T_EMBEDDED_PERF_MONITOR] = "PERFMON",
100 	[T_AST] = "AST",
101 };
102 
103 static inline bool
104 usertrap_p(struct trapframe *tf)
105 {
106 	return (tf->tf_srr1 & PSL_PR) != 0;
107 }
108 
109 static int
110 mchk_exception(struct trapframe *tf, ksiginfo_t *ksi)
111 {
112 	const bool usertrap = usertrap_p(tf);
113 	const vaddr_t faultva = tf->tf_mcar;
114 	struct cpu_info * const ci = curcpu();
115 	int rv = EFAULT;
116 
117 	if (usertrap)
118 		ci->ci_ev_umchk.ev_count++;
119 
120 	if (rv != 0 && usertrap) {
121 		KSI_INIT_TRAP(ksi);
122 		ksi->ksi_signo = SIGSEGV;
123 		ksi->ksi_trap = EXC_DSI;
124 		ksi->ksi_code = SEGV_ACCERR;
125 		ksi->ksi_addr = (void *)faultva;
126 	}
127 
128 	return rv;
129 }
130 
131 static inline vm_prot_t
132 get_faulttype(const struct trapframe * const tf)
133 {
134 	return VM_PROT_READ | (tf->tf_esr & ESR_ST ? VM_PROT_WRITE : 0);
135 }
136 
137 static inline struct vm_map *
138 get_faultmap(const struct trapframe * const tf, register_t psl_mask)
139 {
140 	return (tf->tf_srr1 & psl_mask)
141 	    ? &curlwp->l_proc->p_vmspace->vm_map
142 	    : kernel_map;
143 }
144 
145 /*
146  * We could use pmap_pte_lookip but this slightly faster since we already
147  * the segtab pointers in cpu_info.
148  */
149 static inline pt_entry_t *
150 trap_pte_lookup(struct trapframe *tf, vaddr_t va, register_t psl_mask)
151 {
152 	struct pmap_segtab ** const stps = &curcpu()->ci_pmap_kern_segtab;
153 	struct pmap_segtab * const stp = stps[(tf->tf_srr1 / psl_mask) & 1];
154 	if (__predict_false(stp == NULL))
155 		return NULL;
156 	pt_entry_t *ptep = stp->seg_tab[va >> SEGSHIFT];
157 	if (__predict_false(ptep == NULL))
158 		return NULL;
159 	return ptep + ((va & SEGOFSET) >> PAGE_SHIFT);
160 }
161 
162 static int
163 pagefault(struct vm_map *map, vaddr_t va, vm_prot_t ftype, bool usertrap)
164 {
165 	struct lwp * const l = curlwp;
166 	int rv;
167 
168 //	printf("%s(%p,%#lx,%u,%u)\n", __func__, map, va, ftype, usertrap);
169 
170 	if (usertrap) {
171 #ifdef KERN_SA
172 		if (l->l_flag & LW_SA) {
173 			l->l_savp->savp_faultaddr = va;
174 			l->l_pflag |= LP_SA_PAGEFAULT;
175 		}
176 #endif
177 		rv = uvm_fault(map, trunc_page(va), ftype);
178 		if (rv == 0)
179 			uvm_grow(l->l_proc, trunc_page(va));
180 #ifdef KERN_SA
181 		l->l_pflag &= ~LP_SA_PAGEFAULT;
182 #endif
183 	} else {
184 		if (cpu_intr_p())
185 			return EFAULT;
186 
187 		struct pcb * const pcb = lwp_getpcb(l);
188 		struct faultbuf * const fb = pcb->pcb_onfault;
189 		pcb->pcb_onfault = NULL;
190 		rv = uvm_fault(map, trunc_page(va), ftype);
191 		pcb->pcb_onfault = fb;
192 		if (map != kernel_map) {
193 			if (rv == 0)
194 				uvm_grow(l->l_proc, trunc_page(va));
195 #ifdef KERN_SA
196 			l->l_pflag &= ~LP_SA_PAGEFAULT;
197 #endif
198 		}
199 		if (rv == EACCES)
200 			rv = EFAULT;
201 	}
202 	return rv;
203 }
204 
205 static int
206 dsi_exception(struct trapframe *tf, ksiginfo_t *ksi)
207 {
208 	const vaddr_t faultva = tf->tf_dear;
209 	const vm_prot_t ftype = get_faulttype(tf);
210 	struct vm_map * const faultmap = get_faultmap(tf, PSL_DS);
211 	const bool usertrap = usertrap_p(tf);
212 
213 	kpreempt_disable();
214 	struct cpu_info * const ci = curcpu();
215 
216 	if (usertrap)
217 		ci->ci_ev_udsi.ev_count++;
218 	else
219 		ci->ci_ev_kdsi.ev_count++;
220 
221 	/*
222 	 * If we had a TLB entry (which we must have had to get this exception),
223 	 * we certainly have a PTE.
224 	 */
225 	pt_entry_t * const ptep = trap_pte_lookup(tf, trunc_page(faultva),
226 	    PSL_DS);
227 	KASSERT(ptep != NULL);
228 	pt_entry_t pte = *ptep;
229 
230 	if ((ftype & VM_PROT_WRITE)
231 	    && ((pte & (PTE_xW|PTE_UNMODIFIED)) == (PTE_xW|PTE_UNMODIFIED))) {
232 		const paddr_t pa = pte_to_paddr(pte);
233 		struct vm_page * const pg = PHYS_TO_VM_PAGE(pa);
234 		KASSERT(pg);
235 
236 		if (!VM_PAGE_MD_MODIFIED_P(pg)) {
237 			pmap_page_set_attributes(pg, VM_PAGE_MD_MODIFIED);
238 		}
239 		pte &= ~PTE_UNMODIFIED;
240 		*ptep = pte;
241 		pmap_tlb_update_addr(faultmap->pmap, trunc_page(faultva),
242 		    pte, 0);
243 		kpreempt_enable();
244 		return 0;
245 	}
246 	kpreempt_enable();
247 
248 	int rv = pagefault(faultmap, faultva, ftype, usertrap);
249 
250 	/*
251 	 * We can't get a MAPERR here since that's a different exception.
252 	 */
253 	if (__predict_false(rv != 0 && usertrap)) {
254 		ci->ci_ev_udsi_fatal.ev_count++;
255 		KSI_INIT_TRAP(ksi);
256 		ksi->ksi_signo = SIGSEGV;
257 		ksi->ksi_trap = EXC_DSI;
258 		ksi->ksi_code = SEGV_ACCERR;
259 		ksi->ksi_addr = (void *)faultva;
260 	}
261 	return rv;
262 }
263 
264 static int
265 isi_exception(struct trapframe *tf, ksiginfo_t *ksi)
266 {
267 	const vaddr_t faultva = trunc_page(tf->tf_srr0);
268 	struct vm_map * const faultmap = get_faultmap(tf, PSL_IS);
269 	const bool usertrap = usertrap_p(tf);
270 
271 	kpreempt_disable();
272 	struct cpu_info * const ci = curcpu();
273 
274 	if (usertrap)
275 		ci->ci_ev_isi.ev_count++;
276 	else
277 		ci->ci_ev_kisi.ev_count++;
278 
279 	/*
280 	 * If we had a TLB entry (which we must have had to get this exception),
281 	 * we certainly have a PTE.
282 	 */
283 	pt_entry_t * const ptep = trap_pte_lookup(tf, trunc_page(faultva),
284 	    PSL_IS);
285 	if (ptep == NULL)
286 		dump_trapframe(tf);
287 	KASSERT(ptep != NULL);
288 	pt_entry_t pte = *ptep;
289 
290 	if ((pte & PTE_UNSYNCED) == PTE_UNSYNCED) {
291 		const paddr_t pa = pte_to_paddr(pte);
292 		struct vm_page * const pg = PHYS_TO_VM_PAGE(pa);
293 		KASSERT(pg);
294 
295 		if (!VM_PAGE_MD_EXECPAGE_P(pg)) {
296 			ci->ci_softc->cpu_ev_exec_trap_sync.ev_count++;
297 			dcache_wb_page(pa);
298 			icache_inv_page(pa);
299 			pmap_page_set_attributes(pg, VM_PAGE_MD_EXECPAGE);
300 		}
301 		pte &= ~PTE_UNSYNCED;
302 		pte |= PTE_xX;
303 		*ptep = pte;
304 		pmap_tlb_update_addr(faultmap->pmap, trunc_page(faultva),
305 		    pte, 0);
306 		kpreempt_enable();
307 		return false;
308 	}
309 	kpreempt_enable();
310 
311 	int rv = pagefault(faultmap, faultva, VM_PROT_READ|VM_PROT_EXECUTE,
312 	    usertrap);
313 
314 	if (__predict_false(rv != 0 && usertrap)) {
315 		/*
316 		 * We can't get a MAPERR here since
317 		 * that's a different exception.
318 		 */
319 		ci->ci_ev_isi_fatal.ev_count++;
320 		KSI_INIT_TRAP(ksi);
321 		ksi->ksi_signo = SIGSEGV;
322 		ksi->ksi_trap = EXC_ISI;
323 		ksi->ksi_code = SEGV_ACCERR;
324 		ksi->ksi_addr = (void *)tf->tf_srr0; /* not truncated */
325 	}
326 	return rv;
327 }
328 
329 static int
330 dtlb_exception(struct trapframe *tf, ksiginfo_t *ksi)
331 {
332 	const vaddr_t faultva = tf->tf_dear;
333 	const vm_prot_t ftype = get_faulttype(tf);
334 	struct vm_map * const faultmap = get_faultmap(tf, PSL_DS);
335 	struct cpu_info * const ci = curcpu();
336 	const bool usertrap = usertrap_p(tf);
337 
338 #if 0
339 	/*
340 	 * This is what pte_load in trap_subr.S does for us.
341 	 */
342 	const pt_entry_t * const ptep =
343 	    trap_pte_lookup(tf, trunc_page(faultva), PSL_DS);
344 	if (ptep != NULL && !usertrap && pte_valid_p(*ptep)) {
345 		tlb_update_addr(trunc_page(faultva), KERNEL_PID, *ptep, true);
346 		ci->ci_ev_tlbmiss_soft.ev_count++;
347 		return 0;
348 	}
349 #endif
350 
351 	ci->ci_ev_dtlbmiss_hard.ev_count++;
352 
353 //	printf("pagefault(%p,%#lx,%u,%u)", faultmap, faultva, ftype, usertrap);
354 	int rv = pagefault(faultmap, faultva, ftype, usertrap);
355 //	printf(": %d\n", rv);
356 
357 	if (__predict_false(rv != 0 && usertrap)) {
358 		ci->ci_ev_udsi_fatal.ev_count++;
359 		KSI_INIT_TRAP(ksi);
360 		ksi->ksi_signo = SIGSEGV;
361 		ksi->ksi_trap = EXC_DSI;
362 		ksi->ksi_code = (rv == EACCES ? SEGV_ACCERR : SEGV_MAPERR);
363 		ksi->ksi_addr = (void *)faultva;
364 	}
365 	return rv;
366 }
367 
368 static int
369 itlb_exception(struct trapframe *tf, ksiginfo_t *ksi)
370 {
371 	struct vm_map * const faultmap = get_faultmap(tf, PSL_IS);
372 	const vaddr_t faultva = tf->tf_srr0;
373 	struct cpu_info * const ci = curcpu();
374 	const bool usertrap = usertrap_p(tf);
375 
376 	ci->ci_ev_itlbmiss_hard.ev_count++;
377 
378 	int rv = pagefault(faultmap, faultva, VM_PROT_READ|VM_PROT_EXECUTE,
379 	    usertrap);
380 
381 	if (__predict_false(rv != 0 && usertrap)) {
382 		ci->ci_ev_isi_fatal.ev_count++;
383 		KSI_INIT_TRAP(ksi);
384 		ksi->ksi_signo = SIGSEGV;
385 		ksi->ksi_trap = EXC_ISI;
386 		ksi->ksi_code = (rv == EACCES ? SEGV_ACCERR : SEGV_MAPERR);
387 		ksi->ksi_addr = (void *)tf->tf_srr0;
388 	}
389 	return rv;
390 }
391 
392 static int
393 spe_exception(struct trapframe *tf, ksiginfo_t *ksi)
394 {
395 	struct cpu_info * const ci = curcpu();
396 
397 	if (!usertrap_p(tf))
398 		return EPERM;
399 
400 	ci->ci_ev_vec.ev_count++;
401 
402 #ifdef PPC_HAVE_SPE
403 	vec_enable();
404 	return 0;
405 #else
406 	KSI_INIT_TRAP(ksi);
407 	ksi->ksi_signo = SIGILL;
408 	ksi->ksi_trap = EXC_PGM;
409 	ksi->ksi_code = ILL_ILLOPC;
410 	ksi->ksi_addr = (void *)tf->tf_srr0;
411 	return EPERM;
412 #endif
413 }
414 
415 static bool
416 emulate_opcode(struct trapframe *tf, ksiginfo_t *ksi)
417 {
418 	uint32_t opcode;
419         if (copyin((void *)tf->tf_srr0, &opcode, sizeof(opcode)) != 0)
420 		return false;
421 
422 	if (opcode == OPC_LWSYNC)
423 		return true;
424 
425 	if (OPC_MFSPR_P(opcode, SPR_PVR)) {
426 		__asm ("mfpvr %0" : "=r"(tf->tf_fixreg[OPC_MFSPR_REG(opcode)]));
427 		return true;
428 	}
429 
430 	/*
431 	 * If we bothered to emulate FP, we would try to do so here.
432 	 */
433 	return false;
434 }
435 
436 static int
437 pgm_exception(struct trapframe *tf, ksiginfo_t *ksi)
438 {
439 	struct cpu_info * const ci = curcpu();
440 	int rv = EPERM;
441 
442 	if (!usertrap_p(tf))
443 		return rv;
444 
445 	ci->ci_ev_pgm.ev_count++;
446 
447 	if (tf->tf_esr & ESR_PTR) {
448 		struct proc *p = curlwp->l_proc;
449 		if (p->p_raslist != NULL
450 		    && ras_lookup(p, (void *)tf->tf_srr0) != (void *) -1) {
451 			tf->tf_srr0 += 4;
452 			return 0;
453 		}
454 	}
455 
456 	if (tf->tf_esr & (ESR_PIL|ESR_PPR)) {
457 		if (emulate_opcode(tf, ksi)) {
458 			tf->tf_srr0 += 4;
459 			return 0;
460 		}
461 	}
462 
463 	KSI_INIT_TRAP(ksi);
464 	ksi->ksi_signo = SIGILL;
465 	ksi->ksi_trap = EXC_PGM;
466 	if (tf->tf_esr & ESR_PIL) {
467 		ksi->ksi_code = ILL_ILLOPC;
468 	} else if (tf->tf_esr & ESR_PPR) {
469 		ksi->ksi_code = ILL_PRVOPC;
470 	} else if (tf->tf_esr & ESR_PTR) {
471 		ksi->ksi_signo = SIGTRAP;
472 		ksi->ksi_code = TRAP_BRKPT;
473 	} else {
474 		ksi->ksi_code = 0;
475 	}
476 	ksi->ksi_addr = (void *)tf->tf_srr0;
477 	return rv;
478 }
479 
480 static int
481 debug_exception(struct trapframe *tf, ksiginfo_t *ksi)
482 {
483 	struct cpu_info * const ci = curcpu();
484 	int rv = EPERM;
485 
486 	if (!usertrap_p(tf))
487 		return rv;
488 
489 	ci->ci_ev_debug.ev_count++;
490 
491 	/*
492 	 * Ack the interrupt.
493 	 */
494 	mtspr(SPR_DBSR, tf->tf_esr);
495 	KASSERT(tf->tf_esr & (DBSR_IAC1|DBSR_IAC2));
496 	KASSERT((tf->tf_srr1 & PSL_SE) == 0);
497 
498 	/*
499 	 * Disable debug events
500 	 */
501 	mtspr(SPR_DBCR1, 0);
502 	mtspr(SPR_DBCR0, 0);
503 
504 	/*
505 	 * Tell the debugger ...
506 	 */
507 	KSI_INIT_TRAP(ksi);
508 	ksi->ksi_signo = SIGTRAP;
509 	ksi->ksi_trap = EXC_TRC;
510 	ksi->ksi_addr = (void *)tf->tf_srr0;
511 	ksi->ksi_code = TRAP_TRACE;
512 	return rv;
513 }
514 
515 static int
516 ali_exception(struct trapframe *tf, ksiginfo_t *ksi)
517 {
518 	struct cpu_info * const ci = curcpu();
519 	int rv = EFAULT;
520 
521 	ci->ci_ev_ali.ev_count++;
522 
523 	if (rv != 0 && usertrap_p(tf)) {
524 		ci->ci_ev_ali_fatal.ev_count++;
525 		KSI_INIT_TRAP(ksi);
526 		ksi->ksi_signo = SIGILL;
527 		ksi->ksi_trap = EXC_PGM;
528 		if (tf->tf_esr & ESR_PIL)
529 			ksi->ksi_code = ILL_ILLOPC;
530 		else if (tf->tf_esr & ESR_PPR)
531 			ksi->ksi_code = ILL_PRVOPC;
532 		else if (tf->tf_esr & ESR_PTR)
533 			ksi->ksi_code = ILL_ILLTRP;
534 		else
535 			ksi->ksi_code = 0;
536 		ksi->ksi_addr = (void *)tf->tf_srr0;
537 	}
538 	return rv;
539 }
540 
541 static int
542 embedded_fp_data_exception(struct trapframe *tf, ksiginfo_t *ksi)
543 {
544 	struct cpu_info * const ci = curcpu();
545 	int rv = EFAULT;
546 
547 	ci->ci_ev_fpu.ev_count++;
548 
549 	if (rv != 0 && usertrap_p(tf)) {
550 		KSI_INIT_TRAP(ksi);
551 #ifdef PPC_HAVE_SPE
552 		ksi->ksi_signo = SIGFPE;
553 		ksi->ksi_trap = tf->tf_exc;
554 		ksi->ksi_code = vec_siginfo_code(tf);
555 #else
556 		ksi->ksi_signo = SIGILL;
557 		ksi->ksi_trap = EXC_PGM;
558 		ksi->ksi_code = ILL_ILLOPC;
559 #endif
560 		ksi->ksi_addr = (void *)tf->tf_srr0;
561 	}
562 	return rv;
563 }
564 
565 static int
566 embedded_fp_round_exception(struct trapframe *tf, ksiginfo_t *ksi)
567 {
568 	struct cpu_info * const ci = curcpu();
569 	int rv = EDOM;
570 
571 	ci->ci_ev_fpu.ev_count++;
572 
573 	if (rv != 0 && usertrap_p(tf)) {
574 		KSI_INIT_TRAP(ksi);
575 #ifdef PPC_HAVE_SPE
576 		ksi->ksi_signo = SIGFPE;
577 		ksi->ksi_trap = tf->tf_exc;
578 		ksi->ksi_code = vec_siginfo_code(tf);
579 #else
580 		ksi->ksi_signo = SIGILL;
581 		ksi->ksi_trap = EXC_PGM;
582 		ksi->ksi_code = ILL_ILLOPC;
583 #endif
584 		ksi->ksi_addr = (void *)tf->tf_srr0;
585 	}
586 	return rv;
587 }
588 
589 static void
590 dump_trapframe(const struct trapframe *tf)
591 {
592 	printf("trapframe %p (exc=%x srr0/1=%#lx/%#lx esr/dear=%#x/%#lx)\n",
593 	    tf, tf->tf_exc, tf->tf_srr0, tf->tf_srr1, tf->tf_esr, tf->tf_dear);
594 	printf("lr =%08lx ctr=%08lx cr =%08x xer=%08x\n",
595 	    tf->tf_lr, tf->tf_ctr, tf->tf_cr, tf->tf_xer);
596 	for (u_int r = 0; r < 32; r += 4) {
597 		printf("r%02u=%08lx r%02u=%08lx r%02u=%08lx r%02u=%08lx\n",
598 		    r+0, tf->tf_fixreg[r+0], r+1, tf->tf_fixreg[r+1],
599 		    r+2, tf->tf_fixreg[r+2], r+3, tf->tf_fixreg[r+3]);
600 	}
601 }
602 static bool
603 ddb_exception(struct trapframe *tf)
604 {
605 #if 0
606 	const register_t ddb_trapfunc = (uintptr_t) cpu_Debugger;
607 	if ((tf->tf_esr & ESR_PTR) == 0)
608 		return false;
609 	if (ddb_trapfunc <= tf->tf_srr0 && tf->tf_srr0 <= ddb_trapfunc+16) {
610 		register_t srr0 = tf->tf_srr0;
611 		if (kdb_trap(tf->tf_exc, tf)) {
612 			if (srr0 == tf->tf_srr0)
613 				tf->tf_srr0 += 4;
614 			return true;
615 		}
616 	}
617 	return false;
618 #else
619 #if 0
620 	struct cpu_info * const ci = curcpu();
621 	struct cpu_softc * const cpu = ci->ci_softc;
622 	printf("CPL stack:");
623 	if (ci->ci_idepth >= 0) {
624 		for (u_int i = 0; i <= ci->ci_idepth; i++) {
625 			printf(" [%u]=%u", i, cpu->cpu_pcpls[i]);
626 		}
627 	}
628 	printf(" %u\n", ci->ci_cpl);
629 	dump_trapframe(tf);
630 #endif
631 	if (kdb_trap(tf->tf_exc, tf)) {
632 		tf->tf_srr0 += 4;
633 		return true;
634 	}
635 	return false;
636 #endif
637 }
638 
639 static bool
640 onfaulted(struct trapframe *tf, register_t rv)
641 {
642 	struct lwp * const l = curlwp;
643 	struct pcb * const pcb = lwp_getpcb(l);
644 	struct faultbuf * const fb = pcb->pcb_onfault;
645 	if (fb == NULL)
646 		return false;
647 	tf->tf_srr0 = fb->fb_pc;
648 	tf->tf_srr1 = fb->fb_msr;
649 	tf->tf_cr = fb->fb_cr;
650 	tf->tf_fixreg[1] = fb->fb_sp;
651 	tf->tf_fixreg[2] = fb->fb_r2;
652 	tf->tf_fixreg[3] = rv;
653 	pcb->pcb_onfault = NULL;
654 	return true;
655 }
656 
657 void
658 trap(enum ppc_booke_exceptions trap_code, struct trapframe *tf)
659 {
660 	const bool usertrap = usertrap_p(tf);
661 	struct cpu_info * const ci = curcpu();
662 	struct lwp * const l = curlwp;
663 	struct proc * const p = l->l_proc;
664 	ksiginfo_t ksi;
665 	int rv = EACCES;
666 
667 	ci->ci_ev_traps.ev_count++;
668 	ci->ci_data.cpu_ntrap++;
669 
670 	KASSERTMSG(!usertrap || tf == trapframe(l),
671 	    ("trap: tf=%p is invalid: trapframe(%p)=%p", tf, l, trapframe(l)));
672 
673 #if 0
674 	if (trap_code != T_PROGRAM || usertrap)
675 		printf("trap(enter): %s (tf=%p, esr/dear=%#x/%#lx, srr0/1=%#lx/%#lx, lr=%#lx)\n",
676 		    trap_names[trap_code], tf, tf->tf_esr, tf->tf_dear,
677 		    tf->tf_srr0, tf->tf_srr1, tf->tf_lr);
678 #endif
679 #if 0
680 	if ((register_t)tf >= (register_t)l->l_addr + USPACE
681 	    || (register_t)tf < (register_t)l->l_addr + PAGE_SIZE) {
682 		printf("%s(entry): pid %d.%d (%s): invalid tf addr %p\n",
683 		    __func__, p->p_pid, l->l_lid, p->p_comm, tf);
684 		dump_trapframe(tf);
685 		Debugger();
686 	}
687 #endif
688 #if 0
689 	if ((mfmsr() & PSL_CE) == 0) {
690 		printf("%s(entry): pid %d.%d (%s): %s: PSL_CE (%#lx) not set\n",
691 		    __func__, p->p_pid, l->l_lid, p->p_comm,
692 		    trap_names[trap_code], mfmsr());
693 		dump_trapframe(tf);
694 	}
695 #endif
696 
697 	if (usertrap && (tf->tf_fixreg[1] & 0x80000000)) {
698 		printf("%s(entry): pid %d.%d (%s): %s invalid sp %#lx (sprg1=%#lx)\n",
699 		    __func__, p->p_pid, l->l_lid, p->p_comm,
700 		    trap_names[trap_code], tf->tf_fixreg[1], mfspr(SPR_SPRG1));
701 		dump_trapframe(tf);
702 		Debugger();
703 	}
704 
705 	if (usertrap && (tf->tf_srr1 & (PSL_DS|PSL_IS)) != (PSL_DS|PSL_IS)) {
706 		printf("%s(entry): pid %d.%d (%s): %s invalid PSL %#lx\n",
707 		    __func__, p->p_pid, l->l_lid, p->p_comm,
708 		    trap_names[trap_code], tf->tf_srr1);
709 		dump_trapframe(tf);
710 		Debugger();
711 	}
712 
713 	switch (trap_code) {
714 	case T_CRITIAL_INPUT:
715 	case T_EXTERNAL_INPUT:
716 	case T_DECREMENTER:
717 	case T_FIXED_INTERVAL:
718 	case T_WATCHDOG:
719 	case T_SYSTEM_CALL:
720 	default:
721 		panic("trap: unexcepted trap code %d! (tf=%p, srr0/1=%#lx/%#lx)",
722 		    trap_code, tf, tf->tf_srr0, tf->tf_srr1);
723 	case T_MACHINE_CHECK:
724 		rv = mchk_exception(tf, &ksi);
725 		break;
726 	case T_DSI:
727 		rv = dsi_exception(tf, &ksi);
728 		break;
729 	case T_ISI:
730 		rv = isi_exception(tf, &ksi);
731 		break;
732 	case T_ALIGNMENT:
733 		rv = ali_exception(tf, &ksi);
734 		break;
735 	case T_SPE_UNAVAILABLE:
736 		rv = spe_exception(tf, &ksi);
737 		break;
738 	case T_PROGRAM:
739 #ifdef DDB
740 		if (!usertrap && ddb_exception(tf))
741 			return;
742 #endif
743 		rv = pgm_exception(tf, &ksi);
744 		break;
745 	case T_FP_UNAVAILABLE:
746 	case T_AP_UNAVAILABLE:
747 		panic("trap: unexcepted trap code %d! (tf=%p, srr0/1=%#lx/%#lx)",
748 		    trap_code, tf, tf->tf_srr0, tf->tf_srr1);
749 	case T_DATA_TLB_ERROR:
750 		rv = dtlb_exception(tf, &ksi);
751 		break;
752 	case T_INSTRUCTION_TLB_ERROR:
753 		rv = itlb_exception(tf, &ksi);
754 		break;
755 	case T_DEBUG:
756 #ifdef DDB
757 		if (!usertrap && ddb_exception(tf))
758 			return;
759 #endif
760 		rv = debug_exception(tf, &ksi);
761 		break;
762 	case T_EMBEDDED_FP_DATA:
763 		rv = embedded_fp_data_exception(tf, &ksi);
764 		break;
765 	case T_EMBEDDED_FP_ROUND:
766 		rv = embedded_fp_round_exception(tf, &ksi);
767 		break;
768 	case T_EMBEDDED_PERF_MONITOR:
769 		//db_stack_trace_print(tf->tf_fixreg[1], true, 40, "", printf);
770 		dump_trapframe(tf);
771 		rv = EPERM;
772 		break;
773 	case T_AST:
774 		KASSERT(usertrap);
775 		ci->ci_astpending = 0;		/* we are about to do it */
776 		ci->ci_data.cpu_nsoft++;
777 		if (l->l_pflag & LP_OWEUPC) {
778 			l->l_pflag &= ~LP_OWEUPC;
779 			ADDUPROF(l);
780 		}
781 		/* Check whether we are being preempted. */
782 		if (ci->ci_want_resched)
783 			preempt();
784 		if (tf->tf_fixreg[1] & 0x80000000) {
785 			printf("%s(ast-exit): pid %d.%d (%s): invalid sp %#lx\n",
786 			    __func__, p->p_pid, l->l_lid, p->p_comm,
787 			    tf->tf_fixreg[1]);
788 			dump_trapframe(tf);
789 			Debugger();
790 		}
791 		if ((tf->tf_srr1 & (PSL_DS|PSL_IS)) != (PSL_DS|PSL_IS)) {
792 			printf("%s(entry): pid %d.%d (%s): %s invalid PSL %#lx\n",
793 			    __func__, p->p_pid, l->l_lid, p->p_comm,
794 			    trap_names[trap_code], tf->tf_srr1);
795 			dump_trapframe(tf);
796 			Debugger();
797 		}
798 #if 0
799 		if ((mfmsr() & PSL_CE) == 0) {
800 			printf("%s(exit): pid %d.%d (%s): %s: PSL_CE (%#lx) not set\n",
801 			    __func__, p->p_pid, l->l_lid, p->p_comm,
802 			    trap_names[trap_code], mfmsr());
803 			dump_trapframe(tf);
804 		}
805 #endif
806 		userret(l, tf);
807 		return;
808 	}
809 	if (!usertrap) {
810 		if (rv != 0) {
811 			if (!onfaulted(tf, rv)) {
812 				db_stack_trace_print(tf->tf_fixreg[1], true, 40, "", printf);
813 				dump_trapframe(tf);
814 				panic("%s: pid %d.%d (%s): %s exception in kernel mode"
815 				    " (tf=%p, dear=%#lx, esr=%#x,"
816 				    " srr0/1=%#lx/%#lx)",
817 				    __func__, p->p_pid, l->l_lid, p->p_comm,
818 				    trap_names[trap_code], tf, tf->tf_dear,
819 				    tf->tf_esr, tf->tf_srr0, tf->tf_srr1);
820 			}
821 		}
822 #if 0
823 		if (tf->tf_fixreg[1] >= (register_t)l->l_addr + USPACE
824 		    || tf->tf_fixreg[1] < (register_t)l->l_addr + PAGE_SIZE) {
825 			printf("%s(exit): pid %d.%d (%s): invalid kern sp %#lx\n",
826 			    __func__, p->p_pid, l->l_lid, p->p_comm,
827 			    tf->tf_fixreg[1]);
828 			dump_trapframe(tf);
829 			Debugger();
830 		}
831 #endif
832 #if 0
833 		if ((mfmsr() & PSL_CE) == 0) {
834 			printf("%s(exit): pid %d.%d (%s): %s: PSL_CE (%#lx) not set\n",
835 			    __func__, p->p_pid, l->l_lid, p->p_comm,
836 			    trap_names[trap_code], mfmsr());
837 			mtmsr(mfmsr()|PSL_CE);
838 			dump_trapframe(tf);
839 		}
840 #endif
841 	} else {
842 		if (rv == ENOMEM) {
843 			printf("UVM: pid %d.%d (%s), uid %d killed: "
844 			    "out of swap\n",
845 			    p->p_pid, l->l_lid, p->p_comm,
846 			    l->l_cred ?  kauth_cred_geteuid(l->l_cred) : -1);
847 			ksi.ksi_signo = SIGKILL;
848 		}
849 		if (rv != 0) {
850 			if (cpu_printfataltraps) {
851 				printf("%s: pid %d.%d (%s):"
852 				    " %s exception in user mode\n",
853 				    __func__, p->p_pid, l->l_lid, p->p_comm,
854 				    trap_names[trap_code]);
855 				if (cpu_printfataltraps > 1)
856 					dump_trapframe(tf);
857 			}
858 			(*p->p_emul->e_trapsignal)(l, &ksi);
859 		}
860 #ifdef DEBUG
861 		if ((tf->tf_srr1 & (PSL_DS|PSL_IS)) != (PSL_DS|PSL_IS)) {
862 			printf("%s(exit): pid %d.%d (%s): %s invalid PSL %#lx\n",
863 			    __func__, p->p_pid, l->l_lid, p->p_comm,
864 			    trap_names[trap_code], tf->tf_srr1);
865 			dump_trapframe(tf);
866 			Debugger();
867 		}
868 #endif
869 #if 0
870 		if ((mfmsr() & PSL_CE) == 0) {
871 			printf("%s(exit): pid %d.%d (%s): %s: PSL_CE (%#lx) not set\n",
872 			    __func__, p->p_pid, l->l_lid, p->p_comm,
873 			    trap_names[trap_code], mfmsr());
874 			dump_trapframe(tf);
875 		}
876 #endif
877 		userret(l, tf);
878 	}
879 }
880 
881 void
882 upcallret(struct lwp *l)
883 {
884 
885 	mi_userret(l);		/* Invoke MI userret code */
886 }
887 
888 /*
889  * Start a new LWP
890  */
891 void
892 startlwp(void *arg)
893 {
894 	ucontext_t * const uc = arg;
895 	struct lwp * const l = curlwp;
896 
897 	int error = cpu_setmcontext(l, &uc->uc_mcontext, uc->uc_flags);
898 	KASSERT(error == 0);
899 	(void)error;
900         kmem_free(uc, sizeof(ucontext_t));
901 	upcallret(l);
902 }
903