xref: /freebsd/sys/powerpc/aim/aim_machdep.c (revision 86c94d24)
1 /*-
2  * Copyright (C) 1995, 1996 Wolfgang Solfrank.
3  * Copyright (C) 1995, 1996 TooLs GmbH.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *      This product includes software developed by TooLs GmbH.
17  * 4. The name of TooLs GmbH may not be used to endorse or promote products
18  *    derived from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
25  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
26  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
27  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
28  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
29  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 /*-
32  * Copyright (C) 2001 Benno Rice
33  * All rights reserved.
34  *
35  * Redistribution and use in source and binary forms, with or without
36  * modification, are permitted provided that the following conditions
37  * are met:
38  * 1. Redistributions of source code must retain the above copyright
39  *    notice, this list of conditions and the following disclaimer.
40  * 2. Redistributions in binary form must reproduce the above copyright
41  *    notice, this list of conditions and the following disclaimer in the
42  *    documentation and/or other materials provided with the distribution.
43  *
44  * THIS SOFTWARE IS PROVIDED BY Benno Rice ``AS IS'' AND ANY EXPRESS OR
45  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
46  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
47  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
48  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
49  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
50  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
51  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
52  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
53  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
54  *	$NetBSD: machdep.c,v 1.74.2.1 2000/11/01 16:13:48 tv Exp $
55  */
56 
57 #include <sys/cdefs.h>
58 __FBSDID("$FreeBSD$");
59 
60 #include "opt_compat.h"
61 #include "opt_ddb.h"
62 #include "opt_kstack_pages.h"
63 #include "opt_platform.h"
64 
65 #include <sys/param.h>
66 #include <sys/proc.h>
67 #include <sys/systm.h>
68 #include <sys/bio.h>
69 #include <sys/buf.h>
70 #include <sys/bus.h>
71 #include <sys/cons.h>
72 #include <sys/cpu.h>
73 #include <sys/eventhandler.h>
74 #include <sys/exec.h>
75 #include <sys/imgact.h>
76 #include <sys/kdb.h>
77 #include <sys/kernel.h>
78 #include <sys/ktr.h>
79 #include <sys/linker.h>
80 #include <sys/lock.h>
81 #include <sys/malloc.h>
82 #include <sys/mbuf.h>
83 #include <sys/msgbuf.h>
84 #include <sys/mutex.h>
85 #include <sys/ptrace.h>
86 #include <sys/reboot.h>
87 #include <sys/rwlock.h>
88 #include <sys/signalvar.h>
89 #include <sys/syscallsubr.h>
90 #include <sys/sysctl.h>
91 #include <sys/sysent.h>
92 #include <sys/sysproto.h>
93 #include <sys/ucontext.h>
94 #include <sys/uio.h>
95 #include <sys/vmmeter.h>
96 #include <sys/vnode.h>
97 
98 #include <net/netisr.h>
99 
100 #include <vm/vm.h>
101 #include <vm/vm_extern.h>
102 #include <vm/vm_kern.h>
103 #include <vm/vm_page.h>
104 #include <vm/vm_map.h>
105 #include <vm/vm_object.h>
106 #include <vm/vm_pager.h>
107 
108 #include <machine/altivec.h>
109 #ifndef __powerpc64__
110 #include <machine/bat.h>
111 #endif
112 #include <machine/cpu.h>
113 #include <machine/elf.h>
114 #include <machine/fpu.h>
115 #include <machine/hid.h>
116 #include <machine/kdb.h>
117 #include <machine/md_var.h>
118 #include <machine/metadata.h>
119 #include <machine/mmuvar.h>
120 #include <machine/pcb.h>
121 #include <machine/reg.h>
122 #include <machine/sigframe.h>
123 #include <machine/spr.h>
124 #include <machine/trap.h>
125 #include <machine/vmparam.h>
126 #include <machine/ofw_machdep.h>
127 
128 #include <ddb/ddb.h>
129 
130 #include <dev/ofw/openfirm.h>
131 
132 #ifdef __powerpc64__
133 extern int n_slbs;
134 #endif
135 
136 #ifndef __powerpc64__
137 struct bat	battable[16];
138 #endif
139 
140 #ifndef __powerpc64__
141 /* Bits for running on 64-bit systems in 32-bit mode. */
142 extern void	*testppc64, *testppc64size;
143 extern void	*restorebridge, *restorebridgesize;
144 extern void	*rfid_patch, *rfi_patch1, *rfi_patch2;
145 extern void	*trapcode64;
146 
147 extern Elf_Addr	_GLOBAL_OFFSET_TABLE_[];
148 #endif
149 
150 extern void	*rstcode, *rstcodeend;
151 extern void	*trapcode, *trapcodeend;
152 extern void	*generictrap, *generictrap64;
153 extern void	*slbtrap, *slbtrapend;
154 extern void	*alitrap, *aliend;
155 extern void	*dsitrap, *dsiend;
156 extern void	*decrint, *decrsize;
157 extern void     *extint, *extsize;
158 extern void	*dblow, *dbend;
159 extern void	*imisstrap, *imisssize;
160 extern void	*dlmisstrap, *dlmisssize;
161 extern void	*dsmisstrap, *dsmisssize;
162 
163 extern void *ap_pcpu;
164 
165 void aim_cpu_init(vm_offset_t toc);
166 
167 void
168 aim_cpu_init(vm_offset_t toc)
169 {
170 	size_t		trap_offset, trapsize;
171 	vm_offset_t	trap;
172 	register_t	msr, scratch;
173 	uint8_t		*cache_check;
174 	int		cacheline_warn;
175 	#ifndef __powerpc64__
176 	int		ppc64;
177 	#endif
178 
179 	trap_offset = 0;
180 	cacheline_warn = 0;
181 
182 	#ifdef __powerpc64__
183 	/*
184 	 * Switch to 64-bit mode, if the bootloader didn't, before we start
185 	 * using memory beyond what the bootloader might have set up.
186 	 * Guaranteed not to cause an implicit branch since we either (a)
187 	 * started with a 32-bit bootloader below 4 GB or (b) were already in
188 	 * 64-bit mode, making this a no-op.
189 	 */
190 	mtmsrd(mfmsr() | PSL_SF);
191 	#endif
192 
193 	/* Various very early CPU fix ups */
194 	switch (mfpvr() >> 16) {
195 		/*
196 		 * PowerPC 970 CPUs have a misfeature requested by Apple that
197 		 * makes them pretend they have a 32-byte cacheline. Turn this
198 		 * off before we measure the cacheline size.
199 		 */
200 		case IBM970:
201 		case IBM970FX:
202 		case IBM970MP:
203 		case IBM970GX:
204 			scratch = mfspr(SPR_HID5);
205 			scratch &= ~HID5_970_DCBZ_SIZE_HI;
206 			mtspr(SPR_HID5, scratch);
207 			break;
208 	#ifdef __powerpc64__
209 		case IBMPOWER7:
210 		case IBMPOWER7PLUS:
211 		case IBMPOWER8:
212 		case IBMPOWER8E:
213 			/* XXX: get from ibm,slb-size in device tree */
214 			n_slbs = 32;
215 			break;
216 	#endif
217 	}
218 
219 	/*
220 	 * Initialize the interrupt tables and figure out our cache line
221 	 * size and whether or not we need the 64-bit bridge code.
222 	 */
223 
224 	/*
225 	 * Disable translation in case the vector area hasn't been
226 	 * mapped (G5). Note that no OFW calls can be made until
227 	 * translation is re-enabled.
228 	 */
229 
230 	msr = mfmsr();
231 	mtmsr((msr & ~(PSL_IR | PSL_DR)) | PSL_RI);
232 
233 	/*
234 	 * Measure the cacheline size using dcbz
235 	 *
236 	 * Use EXC_PGM as a playground. We are about to overwrite it
237 	 * anyway, we know it exists, and we know it is cache-aligned.
238 	 */
239 
240 	cache_check = (void *)EXC_PGM;
241 
242 	for (cacheline_size = 0; cacheline_size < 0x100; cacheline_size++)
243 		cache_check[cacheline_size] = 0xff;
244 
245 	__asm __volatile("dcbz 0,%0":: "r" (cache_check) : "memory");
246 
247 	/* Find the first byte dcbz did not zero to get the cache line size */
248 	for (cacheline_size = 0; cacheline_size < 0x100 &&
249 	    cache_check[cacheline_size] == 0; cacheline_size++);
250 
251 	/* Work around psim bug */
252 	if (cacheline_size == 0) {
253 		cacheline_warn = 1;
254 		cacheline_size = 32;
255 	}
256 
257 	#ifndef __powerpc64__
258 	/*
259 	 * Figure out whether we need to use the 64 bit PMAP. This works by
260 	 * executing an instruction that is only legal on 64-bit PPC (mtmsrd),
261 	 * and setting ppc64 = 0 if that causes a trap.
262 	 */
263 
264 	ppc64 = 1;
265 
266 	bcopy(&testppc64, (void *)EXC_PGM,  (size_t)&testppc64size);
267 	__syncicache((void *)EXC_PGM, (size_t)&testppc64size);
268 
269 	__asm __volatile("\
270 		mfmsr %0;	\
271 		mtsprg2 %1;	\
272 				\
273 		mtmsrd %0;	\
274 		mfsprg2 %1;"
275 	    : "=r"(scratch), "=r"(ppc64));
276 
277 	if (ppc64)
278 		cpu_features |= PPC_FEATURE_64;
279 
280 	/*
281 	 * Now copy restorebridge into all the handlers, if necessary,
282 	 * and set up the trap tables.
283 	 */
284 
285 	if (cpu_features & PPC_FEATURE_64) {
286 		/* Patch the two instances of rfi -> rfid */
287 		bcopy(&rfid_patch,&rfi_patch1,4);
288 	#ifdef KDB
289 		/* rfi_patch2 is at the end of dbleave */
290 		bcopy(&rfid_patch,&rfi_patch2,4);
291 	#endif
292 	}
293 	#else /* powerpc64 */
294 	cpu_features |= PPC_FEATURE_64;
295 	#endif
296 
297 	trapsize = (size_t)&trapcodeend - (size_t)&trapcode;
298 
299 	/*
300 	 * Copy generic handler into every possible trap. Special cases will get
301 	 * different ones in a minute.
302 	 */
303 	for (trap = EXC_RST; trap < EXC_LAST; trap += 0x20)
304 		bcopy(&trapcode, (void *)trap, trapsize);
305 
306 	#ifndef __powerpc64__
307 	if (cpu_features & PPC_FEATURE_64) {
308 		/*
309 		 * Copy a code snippet to restore 32-bit bridge mode
310 		 * to the top of every non-generic trap handler
311 		 */
312 
313 		trap_offset += (size_t)&restorebridgesize;
314 		bcopy(&restorebridge, (void *)EXC_RST, trap_offset);
315 		bcopy(&restorebridge, (void *)EXC_DSI, trap_offset);
316 		bcopy(&restorebridge, (void *)EXC_ALI, trap_offset);
317 		bcopy(&restorebridge, (void *)EXC_PGM, trap_offset);
318 		bcopy(&restorebridge, (void *)EXC_MCHK, trap_offset);
319 		bcopy(&restorebridge, (void *)EXC_TRC, trap_offset);
320 		bcopy(&restorebridge, (void *)EXC_BPT, trap_offset);
321 	}
322 	#endif
323 
324 	bcopy(&rstcode, (void *)(EXC_RST + trap_offset), (size_t)&rstcodeend -
325 	    (size_t)&rstcode);
326 
327 #ifdef KDB
328 	bcopy(&dblow, (void *)(EXC_MCHK + trap_offset), (size_t)&dbend -
329 	    (size_t)&dblow);
330 	bcopy(&dblow, (void *)(EXC_PGM + trap_offset), (size_t)&dbend -
331 	    (size_t)&dblow);
332 	bcopy(&dblow, (void *)(EXC_TRC + trap_offset), (size_t)&dbend -
333 	    (size_t)&dblow);
334 	bcopy(&dblow, (void *)(EXC_BPT + trap_offset), (size_t)&dbend -
335 	    (size_t)&dblow);
336 #endif
337 	bcopy(&alitrap,  (void *)(EXC_ALI + trap_offset),  (size_t)&aliend -
338 	    (size_t)&alitrap);
339 	bcopy(&dsitrap,  (void *)(EXC_DSI + trap_offset),  (size_t)&dsiend -
340 	    (size_t)&dsitrap);
341 
342 	#ifdef __powerpc64__
343 	/* Set TOC base so that the interrupt code can get at it */
344 	*((void **)TRAP_GENTRAP) = &generictrap;
345 	*((register_t *)TRAP_TOCBASE) = toc;
346 
347 	bcopy(&slbtrap, (void *)EXC_DSE,(size_t)&slbtrapend - (size_t)&slbtrap);
348 	bcopy(&slbtrap, (void *)EXC_ISE,(size_t)&slbtrapend - (size_t)&slbtrap);
349 	#else
350 	/* Set branch address for trap code */
351 	if (cpu_features & PPC_FEATURE_64)
352 		*((void **)TRAP_GENTRAP) = &generictrap64;
353 	else
354 		*((void **)TRAP_GENTRAP) = &generictrap;
355 	*((void **)TRAP_TOCBASE) = _GLOBAL_OFFSET_TABLE_;
356 
357 	/* G2-specific TLB miss helper handlers */
358 	bcopy(&imisstrap, (void *)EXC_IMISS,  (size_t)&imisssize);
359 	bcopy(&dlmisstrap, (void *)EXC_DLMISS,  (size_t)&dlmisssize);
360 	bcopy(&dsmisstrap, (void *)EXC_DSMISS,  (size_t)&dsmisssize);
361 	#endif
362 	__syncicache(EXC_RSVD, EXC_LAST - EXC_RSVD);
363 
364 	/*
365 	 * Restore MSR
366 	 */
367 	mtmsr(msr);
368 
369 	/* Warn if cachline size was not determined */
370 	if (cacheline_warn == 1) {
371 		printf("WARNING: cacheline size undetermined, setting to 32\n");
372 	}
373 
374 	/*
375 	 * Initialise virtual memory. Use BUS_PROBE_GENERIC priority
376 	 * in case the platform module had a better idea of what we
377 	 * should do.
378 	 */
379 	if (cpu_features & PPC_FEATURE_64)
380 		pmap_mmu_install(MMU_TYPE_G5, BUS_PROBE_GENERIC);
381 	else
382 		pmap_mmu_install(MMU_TYPE_OEA, BUS_PROBE_GENERIC);
383 }
384 
385 /*
386  * Shutdown the CPU as much as possible.
387  */
388 void
389 cpu_halt(void)
390 {
391 
392 	OF_exit();
393 }
394 
395 int
396 ptrace_single_step(struct thread *td)
397 {
398 	struct trapframe *tf;
399 
400 	tf = td->td_frame;
401 	tf->srr1 |= PSL_SE;
402 
403 	return (0);
404 }
405 
406 int
407 ptrace_clear_single_step(struct thread *td)
408 {
409 	struct trapframe *tf;
410 
411 	tf = td->td_frame;
412 	tf->srr1 &= ~PSL_SE;
413 
414 	return (0);
415 }
416 
417 void
418 kdb_cpu_clear_singlestep(void)
419 {
420 
421 	kdb_frame->srr1 &= ~PSL_SE;
422 }
423 
424 void
425 kdb_cpu_set_singlestep(void)
426 {
427 
428 	kdb_frame->srr1 |= PSL_SE;
429 }
430 
431 /*
432  * Initialise a struct pcpu.
433  */
434 void
435 cpu_pcpu_init(struct pcpu *pcpu, int cpuid, size_t sz)
436 {
437 #ifdef __powerpc64__
438 /* Copy the SLB contents from the current CPU */
439 memcpy(pcpu->pc_slb, PCPU_GET(slb), sizeof(pcpu->pc_slb));
440 #endif
441 }
442 
443 #ifndef __powerpc64__
444 uint64_t
445 va_to_vsid(pmap_t pm, vm_offset_t va)
446 {
447 	return ((pm->pm_sr[(uintptr_t)va >> ADDR_SR_SHFT]) & SR_VSID_MASK);
448 }
449 
450 #endif
451 
452 vm_offset_t
453 pmap_early_io_map(vm_paddr_t pa, vm_size_t size)
454 {
455 
456 	return (pa);
457 }
458 
459 /* From p3-53 of the MPC7450 RISC Microprocessor Family Reference Manual */
460 void
461 flush_disable_caches(void)
462 {
463 	register_t msr;
464 	register_t msscr0;
465 	register_t cache_reg;
466 	volatile uint32_t *memp;
467 	uint32_t temp;
468 	int i;
469 	int x;
470 
471 	msr = mfmsr();
472 	powerpc_sync();
473 	mtmsr(msr & ~(PSL_EE | PSL_DR));
474 	msscr0 = mfspr(SPR_MSSCR0);
475 	msscr0 &= ~MSSCR0_L2PFE;
476 	mtspr(SPR_MSSCR0, msscr0);
477 	powerpc_sync();
478 	isync();
479 	__asm__ __volatile__("dssall; sync");
480 	powerpc_sync();
481 	isync();
482 	__asm__ __volatile__("dcbf 0,%0" :: "r"(0));
483 	__asm__ __volatile__("dcbf 0,%0" :: "r"(0));
484 	__asm__ __volatile__("dcbf 0,%0" :: "r"(0));
485 
486 	/* Lock the L1 Data cache. */
487 	mtspr(SPR_LDSTCR, mfspr(SPR_LDSTCR) | 0xFF);
488 	powerpc_sync();
489 	isync();
490 
491 	mtspr(SPR_LDSTCR, 0);
492 
493 	/*
494 	 * Perform this in two stages: Flush the cache starting in RAM, then do it
495 	 * from ROM.
496 	 */
497 	memp = (volatile uint32_t *)0x00000000;
498 	for (i = 0; i < 128 * 1024; i++) {
499 		temp = *memp;
500 		__asm__ __volatile__("dcbf 0,%0" :: "r"(memp));
501 		memp += 32/sizeof(*memp);
502 	}
503 
504 	memp = (volatile uint32_t *)0xfff00000;
505 	x = 0xfe;
506 
507 	for (; x != 0xff;) {
508 		mtspr(SPR_LDSTCR, x);
509 		for (i = 0; i < 128; i++) {
510 			temp = *memp;
511 			__asm__ __volatile__("dcbf 0,%0" :: "r"(memp));
512 			memp += 32/sizeof(*memp);
513 		}
514 		x = ((x << 1) | 1) & 0xff;
515 	}
516 	mtspr(SPR_LDSTCR, 0);
517 
518 	cache_reg = mfspr(SPR_L2CR);
519 	if (cache_reg & L2CR_L2E) {
520 		cache_reg &= ~(L2CR_L2IO_7450 | L2CR_L2DO_7450);
521 		mtspr(SPR_L2CR, cache_reg);
522 		powerpc_sync();
523 		mtspr(SPR_L2CR, cache_reg | L2CR_L2HWF);
524 		while (mfspr(SPR_L2CR) & L2CR_L2HWF)
525 			; /* Busy wait for cache to flush */
526 		powerpc_sync();
527 		cache_reg &= ~L2CR_L2E;
528 		mtspr(SPR_L2CR, cache_reg);
529 		powerpc_sync();
530 		mtspr(SPR_L2CR, cache_reg | L2CR_L2I);
531 		powerpc_sync();
532 		while (mfspr(SPR_L2CR) & L2CR_L2I)
533 			; /* Busy wait for L2 cache invalidate */
534 		powerpc_sync();
535 	}
536 
537 	cache_reg = mfspr(SPR_L3CR);
538 	if (cache_reg & L3CR_L3E) {
539 		cache_reg &= ~(L3CR_L3IO | L3CR_L3DO);
540 		mtspr(SPR_L3CR, cache_reg);
541 		powerpc_sync();
542 		mtspr(SPR_L3CR, cache_reg | L3CR_L3HWF);
543 		while (mfspr(SPR_L3CR) & L3CR_L3HWF)
544 			; /* Busy wait for cache to flush */
545 		powerpc_sync();
546 		cache_reg &= ~L3CR_L3E;
547 		mtspr(SPR_L3CR, cache_reg);
548 		powerpc_sync();
549 		mtspr(SPR_L3CR, cache_reg | L3CR_L3I);
550 		powerpc_sync();
551 		while (mfspr(SPR_L3CR) & L3CR_L3I)
552 			; /* Busy wait for L3 cache invalidate */
553 		powerpc_sync();
554 	}
555 
556 	mtspr(SPR_HID0, mfspr(SPR_HID0) & ~HID0_DCE);
557 	powerpc_sync();
558 	isync();
559 
560 	mtmsr(msr);
561 }
562 
563 void
564 cpu_sleep()
565 {
566 	static u_quad_t timebase = 0;
567 	static register_t sprgs[4];
568 	static register_t srrs[2];
569 
570 	jmp_buf resetjb;
571 	struct thread *fputd;
572 	struct thread *vectd;
573 	register_t hid0;
574 	register_t msr;
575 	register_t saved_msr;
576 
577 	ap_pcpu = pcpup;
578 
579 	PCPU_SET(restore, &resetjb);
580 
581 	saved_msr = mfmsr();
582 	fputd = PCPU_GET(fputhread);
583 	vectd = PCPU_GET(vecthread);
584 	if (fputd != NULL)
585 		save_fpu(fputd);
586 	if (vectd != NULL)
587 		save_vec(vectd);
588 	if (setjmp(resetjb) == 0) {
589 		sprgs[0] = mfspr(SPR_SPRG0);
590 		sprgs[1] = mfspr(SPR_SPRG1);
591 		sprgs[2] = mfspr(SPR_SPRG2);
592 		sprgs[3] = mfspr(SPR_SPRG3);
593 		srrs[0] = mfspr(SPR_SRR0);
594 		srrs[1] = mfspr(SPR_SRR1);
595 		timebase = mftb();
596 		powerpc_sync();
597 		flush_disable_caches();
598 		hid0 = mfspr(SPR_HID0);
599 		hid0 = (hid0 & ~(HID0_DOZE | HID0_NAP)) | HID0_SLEEP;
600 		powerpc_sync();
601 		isync();
602 		msr = mfmsr() | PSL_POW;
603 		mtspr(SPR_HID0, hid0);
604 		powerpc_sync();
605 
606 		while (1)
607 			mtmsr(msr);
608 	}
609 	mttb(timebase);
610 	PCPU_SET(curthread, curthread);
611 	PCPU_SET(curpcb, curthread->td_pcb);
612 	pmap_activate(curthread);
613 	powerpc_sync();
614 	mtspr(SPR_SPRG0, sprgs[0]);
615 	mtspr(SPR_SPRG1, sprgs[1]);
616 	mtspr(SPR_SPRG2, sprgs[2]);
617 	mtspr(SPR_SPRG3, sprgs[3]);
618 	mtspr(SPR_SRR0, srrs[0]);
619 	mtspr(SPR_SRR1, srrs[1]);
620 	mtmsr(saved_msr);
621 	if (fputd == curthread)
622 		enable_fpu(curthread);
623 	if (vectd == curthread)
624 		enable_vec(curthread);
625 	powerpc_sync();
626 }
627 
628