xref: /netbsd-src/sys/arch/powerpc/ibm4xx/trap.c (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
1 /*	$NetBSD: trap.c,v 1.85 2020/07/15 09:10:14 rin Exp $	*/
2 
3 /*
4  * Copyright 2001 Wasabi Systems, Inc.
5  * All rights reserved.
6  *
7  * Written by Eduardo Horvath and Simon Burge for Wasabi Systems, Inc.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *      This product includes software developed for the NetBSD Project by
20  *      Wasabi Systems, Inc.
21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22  *    or promote products derived from this software without specific prior
23  *    written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 /*
39  * Copyright (C) 1995, 1996 Wolfgang Solfrank.
40  * Copyright (C) 1995, 1996 TooLs GmbH.
41  * All rights reserved.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  * 3. All advertising materials mentioning features or use of this software
52  *    must display the following acknowledgement:
53  *	This product includes software developed by TooLs GmbH.
54  * 4. The name of TooLs GmbH may not be used to endorse or promote products
55  *    derived from this software without specific prior written permission.
56  *
57  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
58  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
59  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
60  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
61  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
62  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
63  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
64  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
65  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
66  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
67  */
68 
69 #define	__UFETCHSTORE_PRIVATE
70 
71 #include <sys/cdefs.h>
72 __KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.85 2020/07/15 09:10:14 rin Exp $");
73 
74 #ifdef _KERNEL_OPT
75 #include "opt_ddb.h"
76 #include "opt_kgdb.h"
77 #include "opt_ppcarch.h"
78 #endif
79 
80 #include <sys/param.h>
81 #include <sys/cpu.h>
82 #include <sys/kauth.h>
83 #include <sys/proc.h>
84 #include <sys/reboot.h>
85 #include <sys/syscall.h>
86 #include <sys/systm.h>
87 
88 #if defined(KGDB)
89 #include <sys/kgdb.h>
90 #endif
91 
92 #include <uvm/uvm_extern.h>
93 
94 #include <dev/cons.h>
95 
96 #include <machine/fpu.h>
97 #include <machine/frame.h>
98 #include <machine/pcb.h>
99 #include <machine/psl.h>
100 #include <machine/trap.h>
101 
102 #include <powerpc/db_machdep.h>
103 #include <powerpc/spr.h>
104 #include <powerpc/userret.h>
105 
106 #include <powerpc/ibm4xx/cpu.h>
107 #include <powerpc/ibm4xx/pmap.h>
108 #include <powerpc/ibm4xx/spr.h>
109 #include <powerpc/ibm4xx/tlb.h>
110 
111 #include <powerpc/fpu/fpu_extern.h>
112 
113 /* These definitions should probably be somewhere else			XXX */
114 #define	FIRSTARG	3		/* first argument is in reg 3 */
115 #define	NARGREG		8		/* 8 args are in registers */
116 #define	MOREARGS(sp)	((void *)((int)(sp) + 8)) /* more args go here */
117 
118 static int fix_unaligned(struct lwp *l, struct trapframe *tf);
119 
120 void trap(struct trapframe *);	/* Called from locore / trap_subr */
121 #if 0
122 /* Not currently used nor exposed externally in any header file */
123 int badaddr(void *, size_t);
124 int badaddr_read(void *, size_t, int *);
125 #endif
126 int ctx_setup(int, int);
127 
128 #ifdef DEBUG
129 #define TDB_ALL	0x1
130 int trapdebug = /* TDB_ALL */ 0;
131 #define	DBPRINTF(x, y)	if (trapdebug & (x)) printf y
132 #else
133 #define DBPRINTF(x, y)
134 #endif
135 
136 void
137 trap(struct trapframe *tf)
138 {
139 	struct lwp *l = curlwp;
140 	struct proc *p = l->l_proc;
141 	struct pcb *pcb;
142 	int type = tf->tf_exc;
143 	int ftype, rv;
144 	ksiginfo_t ksi;
145 
146 	KASSERT(l->l_stat == LSONPROC);
147 
148 	if (tf->tf_srr1 & PSL_PR) {
149 		LWP_CACHE_CREDS(l, p);
150 		type |= EXC_USER;
151 	}
152 
153 	ftype = VM_PROT_READ;
154 
155 	DBPRINTF(TDB_ALL, ("trap(%x) at %lx from frame %p &frame %p\n",
156 	    type, tf->tf_srr0, tf, &tf));
157 
158 	switch (type) {
159 	case EXC_DEBUG|EXC_USER:
160 		{
161 			int srr2, srr3;
162 
163 			__asm volatile("mfspr %0,0x3f0" :
164 			    "=r" (rv), "=r" (srr2), "=r" (srr3) :);
165 			printf("debug reg is %x srr2 %x srr3 %x\n", rv, srr2,
166 			    srr3);
167 			/* XXX fall through or break here?! */
168 		}
169 		/*
170 		 * DEBUG intr -- probably single-step.
171 		 */
172 	case EXC_TRC|EXC_USER:
173 		tf->tf_srr1 &= ~PSL_SE;
174 		KSI_INIT_TRAP(&ksi);
175 		ksi.ksi_signo = SIGTRAP;
176 		ksi.ksi_trap = EXC_TRC;
177 		ksi.ksi_addr = (void *)tf->tf_srr0;
178 		trapsignal(l, &ksi);
179 		break;
180 
181 	case EXC_DSI:
182 		/* FALLTHROUGH */
183 	case EXC_DTMISS:
184 		{
185 			struct vm_map *map;
186 			vaddr_t va;
187 			struct faultbuf *fb;
188 
189 			pcb = lwp_getpcb(l);
190 			fb = pcb->pcb_onfault;
191 
192 			if (curcpu()->ci_idepth >= 0) {
193 				rv = EFAULT;
194 				goto out;
195 			}
196 
197 			va = tf->tf_dear;
198 			if (tf->tf_pid == KERNEL_PID) {
199 				map = kernel_map;
200 			} else {
201 				map = &p->p_vmspace->vm_map;
202 			}
203 
204 			if (tf->tf_esr & (ESR_DST|ESR_DIZ))
205 				ftype = VM_PROT_WRITE;
206 
207 			DBPRINTF(TDB_ALL,
208 			    ("trap(EXC_DSI) at %lx %s fault on %p esr %x\n",
209 			    tf->tf_srr0,
210 			    (ftype & VM_PROT_WRITE) ? "write" : "read",
211 			    (void *)va, tf->tf_esr));
212 
213 			pcb->pcb_onfault = NULL;
214 			rv = uvm_fault(map, trunc_page(va), ftype);
215 			pcb->pcb_onfault = fb;
216 			if (rv == 0)
217 				return;
218 out:
219 			if (fb != NULL) {
220 				tf->tf_pid = KERNEL_PID;
221 				tf->tf_srr0 = fb->fb_pc;
222 				tf->tf_srr1 |= PSL_IR; /* Re-enable IMMU */
223 				tf->tf_cr = fb->fb_cr;
224 				tf->tf_fixreg[1] = fb->fb_sp;
225 				tf->tf_fixreg[2] = fb->fb_r2;
226 				tf->tf_fixreg[3] = rv;
227 				memcpy(&tf->tf_fixreg[13], fb->fb_fixreg,
228 				    sizeof(fb->fb_fixreg));
229 				return;
230 			}
231 		}
232 		goto brain_damage;
233 
234 	case EXC_DSI|EXC_USER:
235 		/* FALLTHROUGH */
236 	case EXC_DTMISS|EXC_USER:
237 		if (tf->tf_esr & (ESR_DST|ESR_DIZ))
238 			ftype = VM_PROT_WRITE;
239 
240 		DBPRINTF(TDB_ALL,
241 		    ("trap(EXC_DSI|EXC_USER) at %lx %s fault on %lx %x\n",
242 		    tf->tf_srr0, (ftype & VM_PROT_WRITE) ? "write" : "read",
243 		    tf->tf_dear, tf->tf_esr));
244 		KASSERT(l == curlwp && (l->l_stat == LSONPROC));
245 //		KASSERT(curpcb->pcb_onfault == NULL);
246 		rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(tf->tf_dear),
247 		    ftype);
248 		if (rv == 0) {
249 			break;
250 		}
251 		KSI_INIT_TRAP(&ksi);
252 		ksi.ksi_trap = EXC_DSI;
253 		ksi.ksi_addr = (void *)tf->tf_dear;
254 vm_signal:
255 		switch (rv) {
256 		case EINVAL:
257 			ksi.ksi_signo = SIGBUS;
258 			ksi.ksi_code = BUS_ADRERR;
259 			break;
260 		case EACCES:
261 			ksi.ksi_signo = SIGSEGV;
262 			ksi.ksi_code = SEGV_ACCERR;
263 			break;
264 		case ENOMEM:
265 			ksi.ksi_signo = SIGKILL;
266 			printf("UVM: pid %d.%d (%s), uid %d killed: "
267 			       "out of swap\n", p->p_pid, l->l_lid, p->p_comm,
268 			       l->l_cred ? kauth_cred_geteuid(l->l_cred) : -1);
269 			break;
270 		default:
271 			ksi.ksi_signo = SIGSEGV;
272 			ksi.ksi_code = SEGV_MAPERR;
273 			break;
274 		}
275 		trapsignal(l, &ksi);
276 		break;
277 
278 	case EXC_ITMISS|EXC_USER:
279 	case EXC_ISI|EXC_USER:
280 		ftype = VM_PROT_EXECUTE;
281 		DBPRINTF(TDB_ALL,
282 		    ("trap(EXC_ISI|EXC_USER) at %lx execute fault tf %p\n",
283 		    tf->tf_srr0, tf));
284 //		KASSERT(curpcb->pcb_onfault == NULL);
285 		rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(tf->tf_srr0),
286 		    ftype);
287 		if (rv == 0) {
288 			break;
289 		}
290 isi:
291 		KSI_INIT_TRAP(&ksi);
292 		ksi.ksi_trap = EXC_ISI;
293 		ksi.ksi_addr = (void *)tf->tf_srr0;
294 		goto vm_signal;
295 		break;
296 
297 	case EXC_AST|EXC_USER:
298 		cpu_ast(l, curcpu());
299 		break;
300 
301 	case EXC_ALI|EXC_USER:
302 		if (fix_unaligned(l, tf) != 0) {
303 			KSI_INIT_TRAP(&ksi);
304 			ksi.ksi_signo = SIGBUS;
305 			ksi.ksi_trap = EXC_ALI;
306 			ksi.ksi_addr = (void *)tf->tf_dear;
307 			trapsignal(l, &ksi);
308 		} else
309 			tf->tf_srr0 += 4;
310 		break;
311 
312 	case EXC_PGM|EXC_USER:
313 		curcpu()->ci_data.cpu_ntrap++;
314 
315 		KSI_INIT_TRAP(&ksi);
316 		ksi.ksi_trap = EXC_PGM;
317 		ksi.ksi_addr = (void *)tf->tf_srr0;
318 
319 		if (tf->tf_esr & ESR_PTR) {
320 sigtrap:
321 			if (p->p_raslist != NULL &&
322 			    ras_lookup(p, (void *)tf->tf_srr0) != (void *) -1) {
323 				tf->tf_srr1 += 4;
324 				break;
325 			}
326 			ksi.ksi_code = TRAP_BRKPT;
327 			ksi.ksi_signo = SIGTRAP;
328 		} else if (tf->tf_esr & ESR_PPR) {
329 			uint32_t opcode;
330 
331 			rv = copyin((void *)tf->tf_srr0, &opcode,
332 			    sizeof(opcode));
333 			if (rv)
334 				goto isi;
335 			if (emulate_mxmsr(l, tf, opcode)) {
336 				tf->tf_srr0 += 4;
337 				break;
338 			}
339 
340 			ksi.ksi_code = ILL_PRVOPC;
341 			ksi.ksi_signo = SIGILL;
342 		} else {
343 			pcb = lwp_getpcb(l);
344 
345 			if (__predict_false(!fpu_used_p(l))) {
346 				memset(&pcb->pcb_fpu, 0, sizeof(pcb->pcb_fpu));
347 				fpu_mark_used(l);
348 			}
349 
350 			if (fpu_emulate(tf, &pcb->pcb_fpu, &ksi)) {
351 				if (ksi.ksi_signo == 0)	/* was emulated */
352 					break;
353 				else if (ksi.ksi_signo == SIGTRAP)
354 					goto sigtrap;	/* XXX H/W bug? */
355 			} else {
356 				ksi.ksi_code = ILL_ILLOPC;
357 				ksi.ksi_signo = SIGILL;
358 			}
359 		}
360 
361 		trapsignal(l, &ksi);
362 		break;
363 
364 	case EXC_MCHK:
365 		{
366 			struct faultbuf *fb;
367 
368 			pcb = lwp_getpcb(l);
369 			if ((fb = pcb->pcb_onfault) != NULL) {
370 				tf->tf_pid = KERNEL_PID;
371 				tf->tf_srr0 = fb->fb_pc;
372 				tf->tf_srr1 |= PSL_IR; /* Re-enable IMMU */
373 				tf->tf_fixreg[1] = fb->fb_sp;
374 				tf->tf_fixreg[2] = fb->fb_r2;
375 				tf->tf_fixreg[3] = 1; /* Return TRUE */
376 				tf->tf_cr = fb->fb_cr;
377 				memcpy(&tf->tf_fixreg[13], fb->fb_fixreg,
378 				    sizeof(fb->fb_fixreg));
379 				return;
380 			}
381 		}
382 		goto brain_damage;
383 
384 	default:
385 brain_damage:
386 		printf("trap type 0x%x at 0x%lx\n", type, tf->tf_srr0);
387 #if defined(DDB) || defined(KGDB)
388 		if (kdb_trap(type, tf))
389 			return;
390 #endif
391 #ifdef TRAP_PANICWAIT
392 		printf("Press a key to panic.\n");
393 		cngetc();
394 #endif
395 		panic("trap");
396 	}
397 
398 	/* Invoke powerpc userret code */
399 	userret(l, tf);
400 }
401 
402 int
403 ctx_setup(int ctx, int srr1)
404 {
405 	volatile struct pmap *pm;
406 
407 	/* Update PID if we're returning to user mode. */
408 	if (srr1 & PSL_PR) {
409 		pm = curproc->p_vmspace->vm_map.pmap;
410 		if (!pm->pm_ctx) {
411 			ctx_alloc(__UNVOLATILE(pm));
412 		}
413 		ctx = pm->pm_ctx;
414 		if (srr1 & PSL_SE) {
415 			int dbreg, mask = 0x48000000;
416 				/*
417 				 * Set the Internal Debug and
418 				 * Instruction Completion bits of
419 				 * the DBCR0 register.
420 				 *
421 				 * XXX this is also used by jtag debuggers...
422 				 */
423 			__asm volatile("mfspr %0,0x3f2;"
424 			    "or %0,%0,%1;"
425 			    "mtspr 0x3f2,%0;" :
426 			    "=&r" (dbreg) : "r" (mask));
427 		}
428 	}
429 	else if (!ctx) {
430 		ctx = KERNEL_PID;
431 	}
432 	return (ctx);
433 }
434 
435 /*
436  * Used by copyin()/copyout()
437  */
438 extern vaddr_t vmaprange(struct proc *, vaddr_t, vsize_t, int);
439 extern void vunmaprange(vaddr_t, vsize_t);
440 static int bigcopyin(const void *, void *, size_t );
441 static int bigcopyout(const void *, void *, size_t );
442 
443 int
444 copyin(const void *udaddr, void *kaddr, size_t len)
445 {
446 	struct pmap *pm = curproc->p_vmspace->vm_map.pmap;
447 	int rv, msr, pid, tmp, ctx, count = 0;
448 	struct faultbuf env;
449 
450 	/* For bigger buffers use the faster copy */
451 	if (len > 1024)
452 		return (bigcopyin(udaddr, kaddr, len));
453 
454 	if ((rv = setfault(&env))) {
455 		curpcb->pcb_onfault = NULL;
456 		return rv;
457 	}
458 
459 	if (!(ctx = pm->pm_ctx)) {
460 		/* No context -- assign it one */
461 		ctx_alloc(pm);
462 		ctx = pm->pm_ctx;
463 	}
464 
465 	__asm volatile(
466 		"   mfmsr %[msr];"		/* Save MSR */
467 		"   li %[pid],0x20;"
468 		"   andc %[pid],%[msr],%[pid]; mtmsr %[pid];" /* Disable IMMU */
469 		"   isync;"
470 		"   mfpid %[pid];"		/* Save old PID */
471 
472 		"   srwi. %[count],%[len],0x2;"	/* How many words? */
473 		"   beq- 2f;"			/* No words. Go do bytes */
474 		"   mtctr %[count];"
475 		"1: mtpid %[ctx]; isync;"
476 #ifdef PPC_IBM403
477 		"   lswi %[tmp],%[udaddr],4;"	/* Load user word */
478 #else
479 		"   lwz %[tmp],0(%[udaddr]);"
480 #endif
481 		"   addi %[udaddr],%[udaddr],0x4;" /* next udaddr word */
482 		"   sync;"
483 		"   mtpid %[pid]; isync;"
484 #ifdef PPC_IBM403
485 		"   stswi %[tmp],%[kaddr],4;"	/* Store kernel word */
486 #else
487 		"   stw %[tmp],0(%[kaddr]);"
488 #endif
489 		"   dcbst 0,%[kaddr];"		/* flush cache */
490 		"   addi %[kaddr],%[kaddr],0x4;" /* next udaddr word */
491 		"   sync;"
492 		"   bdnz 1b;"			/* repeat */
493 
494 		"2: andi. %[count],%[len],0x3;"	/* How many remaining bytes? */
495 		"   addi %[count],%[count],0x1;"
496 		"   mtctr %[count];"
497 		"3: bdz 10f;"			/* while count */
498 		"   mtpid %[ctx]; isync;"
499 		"   lbz %[tmp],0(%[udaddr]);"	/* Load user byte */
500 		"   addi %[udaddr],%[udaddr],0x1;" /* next udaddr byte */
501 		"   sync;"
502 		"   mtpid %[pid]; isync;"
503 		"   stb %[tmp],0(%[kaddr]);"	/* Store kernel byte */
504 		"   dcbst 0,%[kaddr];"		/* flush cache */
505 		"   addi %[kaddr],%[kaddr],0x1;"
506 		"   sync;"
507 		"   b 3b;"
508 		"10:mtpid %[pid]; mtmsr %[msr]; isync;"
509 						/* Restore PID and MSR */
510 		: [msr] "=&r" (msr), [pid] "=&r" (pid), [tmp] "=&r" (tmp)
511 		: [udaddr] "b" (udaddr), [ctx] "b" (ctx), [kaddr] "b" (kaddr),
512 		  [len] "b" (len), [count] "b" (count));
513 
514 	curpcb->pcb_onfault = NULL;
515 	return 0;
516 }
517 
518 static int
519 bigcopyin(const void *udaddr, void *kaddr, size_t len)
520 {
521 	const char *up;
522 	char *kp = kaddr;
523 	struct lwp *l = curlwp;
524 	struct proc *p;
525 	struct faultbuf env;
526 	int error;
527 
528 	p = l->l_proc;
529 
530 	/*
531 	 * Stolen from physio():
532 	 */
533 	error = uvm_vslock(p->p_vmspace, __UNCONST(udaddr), len, VM_PROT_READ);
534 	if (error) {
535 		return error;
536 	}
537 	up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ);
538 
539 	if ((error = setfault(&env)) == 0) {
540 		memcpy(kp, up, len);
541 	}
542 
543 	curpcb->pcb_onfault = NULL;
544 	vunmaprange((vaddr_t)up, len);
545 	uvm_vsunlock(p->p_vmspace, __UNCONST(udaddr), len);
546 
547 	return error;
548 }
549 
550 int
551 copyout(const void *kaddr, void *udaddr, size_t len)
552 {
553 	struct pmap *pm = curproc->p_vmspace->vm_map.pmap;
554 	int rv, msr, pid, tmp, ctx, count = 0;
555 	struct faultbuf env;
556 
557 	/* For big copies use more efficient routine */
558 	if (len > 1024)
559 		return (bigcopyout(kaddr, udaddr, len));
560 
561 	if ((rv = setfault(&env))) {
562 		curpcb->pcb_onfault = NULL;
563 		return rv;
564 	}
565 
566 	if (!(ctx = pm->pm_ctx)) {
567 		/* No context -- assign it one */
568 		ctx_alloc(pm);
569 		ctx = pm->pm_ctx;
570 	}
571 
572 	__asm volatile(
573 		"   mfmsr %[msr];"		/* Save MSR */
574 		"   li %[pid],0x20;"
575 		"   andc %[pid],%[msr],%[pid]; mtmsr %[pid];" /* Disable IMMU */
576 		"   isync;"
577 		"   mfpid %[pid];"		/* Save old PID */
578 
579 		"   srwi. %[count],%[len],0x2;"	/* How many words? */
580 		"   beq- 2f;"			/* No words. Go do bytes */
581 		"   mtctr %[count];"
582 		"1: mtpid %[pid]; isync;"
583 #ifdef PPC_IBM403
584 		"   lswi %[tmp],%[kaddr],4;"	/* Load kernel word */
585 #else
586 		"   lwz %[tmp],0(%[kaddr]);"
587 #endif
588 		"   addi %[kaddr],%[kaddr],0x4;" /* next kaddr word */
589 		"   sync;"
590 		"   mtpid %[ctx]; isync;"
591 #ifdef PPC_IBM403
592 		"   stswi %[tmp],%[udaddr],4;"	/* Store user word */
593 #else
594 		"   stw %[tmp],0(%[udaddr]);"
595 #endif
596 		"   dcbst 0,%[udaddr];"		/* flush cache */
597 		"   addi %[udaddr],%[udaddr],0x4;" /* next udaddr word */
598 		"   sync;"
599 		"   bdnz 1b;"			/* repeat */
600 
601 		"2: andi. %[count],%[len],0x3;"	/* How many remaining bytes? */
602 		"   addi %[count],%[count],0x1;"
603 		"   mtctr %[count];"
604 		"3: bdz  10f;"			/* while count */
605 		"   mtpid %[pid]; isync;"
606 		"   lbz %[tmp],0(%[kaddr]);"	/* Load kernel byte */
607 		"   addi %[kaddr],%[kaddr],0x1;" /* next kaddr byte */
608 		"   sync;"
609 		"   mtpid %[ctx]; isync;"
610 		"   stb %[tmp],0(%[udaddr]);"	/* Store user byte */
611 		"   dcbst 0,%[udaddr];"		/* flush cache */
612 		"   addi %[udaddr],%[udaddr],0x1;"
613 		"   sync;"
614 		"   b 3b;"
615 		"10:mtpid %[pid]; mtmsr %[msr]; isync;"
616 						/* Restore PID and MSR */
617 		: [msr] "=&r" (msr), [pid] "=&r" (pid), [tmp] "=&r" (tmp)
618 		: [udaddr] "b" (udaddr), [ctx] "b" (ctx), [kaddr] "b" (kaddr),
619 		  [len] "b" (len), [count] "b" (count));
620 
621 	curpcb->pcb_onfault = NULL;
622 	return 0;
623 }
624 
625 static int
626 bigcopyout(const void *kaddr, void *udaddr, size_t len)
627 {
628 	char *up;
629 	const char *kp = (const char *)kaddr;
630 	struct lwp *l = curlwp;
631 	struct proc *p;
632 	struct faultbuf env;
633 	int error;
634 
635 	p = l->l_proc;
636 
637 	/*
638 	 * Stolen from physio():
639 	 */
640 	error = uvm_vslock(p->p_vmspace, udaddr, len, VM_PROT_WRITE);
641 	if (error) {
642 		return error;
643 	}
644 	up = (char *)vmaprange(p, (vaddr_t)udaddr, len,
645 	    VM_PROT_READ | VM_PROT_WRITE);
646 
647 	if ((error = setfault(&env)) == 0) {
648 		memcpy(up, kp, len);
649 	}
650 
651 	curpcb->pcb_onfault = NULL;
652 	vunmaprange((vaddr_t)up, len);
653 	uvm_vsunlock(p->p_vmspace, udaddr, len);
654 
655 	return error;
656 }
657 
658 /*
659  * kcopy(const void *src, void *dst, size_t len);
660  *
661  * Copy len bytes from src to dst, aborting if we encounter a fatal
662  * page fault.
663  *
664  * kcopy() _must_ save and restore the old fault handler since it is
665  * called by uiomove(), which may be in the path of servicing a non-fatal
666  * page fault.
667  */
668 int
669 kcopy(const void *src, void *dst, size_t len)
670 {
671 	struct faultbuf env, *oldfault;
672 	int rv;
673 
674 	oldfault = curpcb->pcb_onfault;
675 	if ((rv = setfault(&env))) {
676 		curpcb->pcb_onfault = oldfault;
677 		return rv;
678 	}
679 
680 	memcpy(dst, src, len);
681 
682 	curpcb->pcb_onfault = oldfault;
683 	return 0;
684 }
685 
686 #if 0
687 int
688 badaddr(void *addr, size_t size)
689 {
690 
691 	return badaddr_read(addr, size, NULL);
692 }
693 
694 int
695 badaddr_read(void *addr, size_t size, int *rptr)
696 {
697 	struct faultbuf env;
698 	int x;
699 
700 	/* Get rid of any stale machine checks that have been waiting.  */
701 	__asm volatile ("sync; isync");
702 
703 	if (setfault(&env)) {
704 		curpcb->pcb_onfault = NULL;
705 		__asm volatile ("sync");
706 		return 1;
707 	}
708 
709 	__asm volatile ("sync");
710 
711 	switch (size) {
712 	case 1:
713 		x = *(volatile int8_t *)addr;
714 		break;
715 	case 2:
716 		x = *(volatile int16_t *)addr;
717 		break;
718 	case 4:
719 		x = *(volatile int32_t *)addr;
720 		break;
721 	default:
722 		panic("badaddr: invalid size (%d)", size);
723 	}
724 
725 	/* Make sure we took the machine check, if we caused one. */
726 	__asm volatile ("sync; isync");
727 
728 	curpcb->pcb_onfault = NULL;
729 	__asm volatile ("sync");	/* To be sure. */
730 
731 	/* Use the value to avoid reorder. */
732 	if (rptr)
733 		*rptr = x;
734 
735 	return 0;
736 }
737 #endif
738 
739 /*
740  * For now, this only deals with the particular unaligned access case
741  * that gcc tends to generate.  Eventually it should handle all of the
742  * possibilities that can happen on a 32-bit PowerPC in big-endian mode.
743  */
744 
745 static int
746 fix_unaligned(struct lwp *l, struct trapframe *tf)
747 {
748 
749 	return -1;
750 }
751 
752 /*
753  * XXX Extremely lame implementations of _ufetch_* / _ustore_*.  IBM 4xx
754  * experts should make versions that are good.
755  */
756 
757 #define UFETCH(sz)							\
758 int									\
759 _ufetch_ ## sz(const uint ## sz ## _t *uaddr, uint ## sz ## _t *valp)	\
760 {									\
761 	return copyin(uaddr, valp, sizeof(*valp));			\
762 }
763 
764 UFETCH(8)
765 UFETCH(16)
766 UFETCH(32)
767 
768 #define USTORE(sz)							\
769 int									\
770 _ustore_ ## sz(uint ## sz ## _t *uaddr, uint ## sz ## _t val)		\
771 {									\
772 	return copyout(&val, uaddr, sizeof(val));			\
773 }
774 
775 USTORE(8)
776 USTORE(16)
777 USTORE(32)
778