xref: /freebsd/sys/i386/include/cpufunc.h (revision 66df505066f51e6d8411b966765d828817f88971)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1993 The Regents of the University of California.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  * $FreeBSD$
32  */
33 
34 /*
35  * Functions to provide access to special i386 instructions.
36  * This in included in sys/systm.h, and that file should be
37  * used in preference to this.
38  */
39 
40 #ifndef _MACHINE_CPUFUNC_H_
41 #define	_MACHINE_CPUFUNC_H_
42 
43 #ifndef _SYS_CDEFS_H_
44 #error this file needs sys/cdefs.h as a prerequisite
45 #endif
46 
47 struct region_descriptor;
48 
49 #define readb(va)	(*(volatile uint8_t *) (va))
50 #define readw(va)	(*(volatile uint16_t *) (va))
51 #define readl(va)	(*(volatile uint32_t *) (va))
52 
53 #define writeb(va, d)	(*(volatile uint8_t *) (va) = (d))
54 #define writew(va, d)	(*(volatile uint16_t *) (va) = (d))
55 #define writel(va, d)	(*(volatile uint32_t *) (va) = (d))
56 
57 #if defined(__GNUCLIKE_ASM) && defined(__CC_SUPPORTS___INLINE)
58 
59 static __inline void
60 breakpoint(void)
61 {
62 	__asm __volatile("int $3");
63 }
64 
65 static __inline __pure2 u_int
66 bsfl(u_int mask)
67 {
68 	u_int	result;
69 
70 	__asm("bsfl %1,%0" : "=r" (result) : "rm" (mask) : "cc");
71 	return (result);
72 }
73 
74 static __inline __pure2 u_int
75 bsrl(u_int mask)
76 {
77 	u_int	result;
78 
79 	__asm("bsrl %1,%0" : "=r" (result) : "rm" (mask) : "cc");
80 	return (result);
81 }
82 
83 static __inline void
84 clflush(u_long addr)
85 {
86 
87 	__asm __volatile("clflush %0" : : "m" (*(char *)addr));
88 }
89 
90 static __inline void
91 clflushopt(u_long addr)
92 {
93 
94 	__asm __volatile(".byte 0x66;clflush %0" : : "m" (*(char *)addr));
95 }
96 
97 static __inline void
98 clts(void)
99 {
100 
101 	__asm __volatile("clts");
102 }
103 
104 static __inline void
105 disable_intr(void)
106 {
107 
108 	__asm __volatile("cli" : : : "memory");
109 }
110 
111 #ifdef _KERNEL
112 static __inline void
113 do_cpuid(u_int ax, u_int *p)
114 {
115 	__asm __volatile("cpuid"
116 	    : "=a" (p[0]), "=b" (p[1]), "=c" (p[2]), "=d" (p[3])
117 	    :  "0" (ax));
118 }
119 
120 static __inline void
121 cpuid_count(u_int ax, u_int cx, u_int *p)
122 {
123 	__asm __volatile("cpuid"
124 	    : "=a" (p[0]), "=b" (p[1]), "=c" (p[2]), "=d" (p[3])
125 	    :  "0" (ax), "c" (cx));
126 }
127 #else
128 static __inline void
129 do_cpuid(u_int ax, u_int *p)
130 {
131 	__asm __volatile(
132 	    "pushl\t%%ebx\n\t"
133 	    "cpuid\n\t"
134 	    "movl\t%%ebx,%1\n\t"
135 	    "popl\t%%ebx"
136 	    : "=a" (p[0]), "=DS" (p[1]), "=c" (p[2]), "=d" (p[3])
137 	    :  "0" (ax));
138 }
139 
140 static __inline void
141 cpuid_count(u_int ax, u_int cx, u_int *p)
142 {
143 	__asm __volatile(
144 	    "pushl\t%%ebx\n\t"
145 	    "cpuid\n\t"
146 	    "movl\t%%ebx,%1\n\t"
147 	    "popl\t%%ebx"
148 	    : "=a" (p[0]), "=DS" (p[1]), "=c" (p[2]), "=d" (p[3])
149 	    :  "0" (ax), "c" (cx));
150 }
151 #endif
152 
153 static __inline void
154 enable_intr(void)
155 {
156 
157 	__asm __volatile("sti");
158 }
159 
160 static __inline void
161 cpu_monitor(const void *addr, u_long extensions, u_int hints)
162 {
163 
164 	__asm __volatile("monitor"
165 	    : : "a" (addr), "c" (extensions), "d" (hints));
166 }
167 
168 static __inline void
169 cpu_mwait(u_long extensions, u_int hints)
170 {
171 
172 	__asm __volatile("mwait" : : "a" (hints), "c" (extensions));
173 }
174 
175 static __inline void
176 lfence(void)
177 {
178 
179 	__asm __volatile("lfence" : : : "memory");
180 }
181 
182 static __inline void
183 mfence(void)
184 {
185 
186 	__asm __volatile("mfence" : : : "memory");
187 }
188 
189 static __inline void
190 sfence(void)
191 {
192 
193 	__asm __volatile("sfence" : : : "memory");
194 }
195 
196 #ifdef _KERNEL
197 
198 #define	HAVE_INLINE_FFS
199 
200 static __inline __pure2 int
201 ffs(int mask)
202 {
203 	/*
204 	 * Note that gcc-2's builtin ffs would be used if we didn't declare
205 	 * this inline or turn off the builtin.  The builtin is faster but
206 	 * broken in gcc-2.4.5 and slower but working in gcc-2.5 and later
207 	 * versions.
208 	 */
209 	 return (mask == 0 ? mask : (int)bsfl((u_int)mask) + 1);
210 }
211 
212 #define	HAVE_INLINE_FFSL
213 
214 static __inline __pure2 int
215 ffsl(long mask)
216 {
217 	return (ffs((int)mask));
218 }
219 
220 #define	HAVE_INLINE_FLS
221 
222 static __inline __pure2 int
223 fls(int mask)
224 {
225 	return (mask == 0 ? mask : (int)bsrl((u_int)mask) + 1);
226 }
227 
228 #define	HAVE_INLINE_FLSL
229 
230 static __inline __pure2 int
231 flsl(long mask)
232 {
233 	return (fls((int)mask));
234 }
235 
236 #endif /* _KERNEL */
237 
238 static __inline void
239 halt(void)
240 {
241 	__asm __volatile("hlt");
242 }
243 
244 static __inline u_char
245 inb(u_int port)
246 {
247 	u_char	data;
248 
249 	__asm __volatile("inb %w1, %0" : "=a" (data) : "Nd" (port));
250 	return (data);
251 }
252 
253 static __inline u_int
254 inl(u_int port)
255 {
256 	u_int	data;
257 
258 	__asm __volatile("inl %w1, %0" : "=a" (data) : "Nd" (port));
259 	return (data);
260 }
261 
262 static __inline void
263 insb(u_int port, void *addr, size_t count)
264 {
265 	__asm __volatile("cld; rep; insb"
266 			 : "+D" (addr), "+c" (count)
267 			 : "d" (port)
268 			 : "memory");
269 }
270 
271 static __inline void
272 insw(u_int port, void *addr, size_t count)
273 {
274 	__asm __volatile("cld; rep; insw"
275 			 : "+D" (addr), "+c" (count)
276 			 : "d" (port)
277 			 : "memory");
278 }
279 
280 static __inline void
281 insl(u_int port, void *addr, size_t count)
282 {
283 	__asm __volatile("cld; rep; insl"
284 			 : "+D" (addr), "+c" (count)
285 			 : "d" (port)
286 			 : "memory");
287 }
288 
289 static __inline void
290 invd(void)
291 {
292 	__asm __volatile("invd");
293 }
294 
295 static __inline u_short
296 inw(u_int port)
297 {
298 	u_short	data;
299 
300 	__asm __volatile("inw %w1, %0" : "=a" (data) : "Nd" (port));
301 	return (data);
302 }
303 
304 static __inline void
305 outb(u_int port, u_char data)
306 {
307 	__asm __volatile("outb %0, %w1" : : "a" (data), "Nd" (port));
308 }
309 
310 static __inline void
311 outl(u_int port, u_int data)
312 {
313 	__asm __volatile("outl %0, %w1" : : "a" (data), "Nd" (port));
314 }
315 
316 static __inline void
317 outsb(u_int port, const void *addr, size_t count)
318 {
319 	__asm __volatile("cld; rep; outsb"
320 			 : "+S" (addr), "+c" (count)
321 			 : "d" (port));
322 }
323 
324 static __inline void
325 outsw(u_int port, const void *addr, size_t count)
326 {
327 	__asm __volatile("cld; rep; outsw"
328 			 : "+S" (addr), "+c" (count)
329 			 : "d" (port));
330 }
331 
332 static __inline void
333 outsl(u_int port, const void *addr, size_t count)
334 {
335 	__asm __volatile("cld; rep; outsl"
336 			 : "+S" (addr), "+c" (count)
337 			 : "d" (port));
338 }
339 
340 static __inline void
341 outw(u_int port, u_short data)
342 {
343 	__asm __volatile("outw %0, %w1" : : "a" (data), "Nd" (port));
344 }
345 
346 static __inline void
347 ia32_pause(void)
348 {
349 	__asm __volatile("pause");
350 }
351 
352 static __inline u_int
353 read_eflags(void)
354 {
355 	u_int	ef;
356 
357 	__asm __volatile("pushfl; popl %0" : "=r" (ef));
358 	return (ef);
359 }
360 
361 static __inline uint64_t
362 rdmsr(u_int msr)
363 {
364 	uint64_t rv;
365 
366 	__asm __volatile("rdmsr" : "=A" (rv) : "c" (msr));
367 	return (rv);
368 }
369 
370 static __inline uint32_t
371 rdmsr32(u_int msr)
372 {
373 	uint32_t low;
374 
375 	__asm __volatile("rdmsr" : "=a" (low) : "c" (msr) : "edx");
376 	return (low);
377 }
378 
379 static __inline uint64_t
380 rdpmc(u_int pmc)
381 {
382 	uint64_t rv;
383 
384 	__asm __volatile("rdpmc" : "=A" (rv) : "c" (pmc));
385 	return (rv);
386 }
387 
388 static __inline uint64_t
389 rdtsc(void)
390 {
391 	uint64_t rv;
392 
393 	__asm __volatile("rdtsc" : "=A" (rv));
394 	return (rv);
395 }
396 
397 static __inline uint64_t
398 rdtsc_ordered_lfence(void)
399 {
400 	lfence();
401 	return (rdtsc());
402 }
403 
404 static __inline uint64_t
405 rdtsc_ordered_mfence(void)
406 {
407 	mfence();
408 	return (rdtsc());
409 }
410 
411 static __inline uint64_t
412 rdtscp(void)
413 {
414 	uint64_t rv;
415 
416 	__asm __volatile("rdtscp" : "=A" (rv) : : "ecx");
417 	return (rv);
418 }
419 
420 static __inline uint64_t
421 rdtscp_aux(uint32_t *aux)
422 {
423 	uint64_t rv;
424 
425 	__asm __volatile("rdtscp" : "=A" (rv), "=c" (*aux));
426 	return (rv);
427 }
428 
429 static __inline uint32_t
430 rdtsc32(void)
431 {
432 	uint32_t rv;
433 
434 	__asm __volatile("rdtsc" : "=a" (rv) : : "edx");
435 	return (rv);
436 }
437 
438 static __inline uint32_t
439 rdtscp32(void)
440 {
441 	uint32_t rv;
442 
443 	__asm __volatile("rdtscp" : "=a" (rv) : : "ecx", "edx");
444 	return (rv);
445 }
446 
447 static __inline void
448 wbinvd(void)
449 {
450 	__asm __volatile("wbinvd");
451 }
452 
453 static __inline void
454 write_eflags(u_int ef)
455 {
456 	__asm __volatile("pushl %0; popfl" : : "r" (ef));
457 }
458 
459 static __inline void
460 wrmsr(u_int msr, uint64_t newval)
461 {
462 	__asm __volatile("wrmsr" : : "A" (newval), "c" (msr));
463 }
464 
465 static __inline void
466 load_cr0(u_int data)
467 {
468 
469 	__asm __volatile("movl %0,%%cr0" : : "r" (data));
470 }
471 
472 static __inline u_int
473 rcr0(void)
474 {
475 	u_int	data;
476 
477 	__asm __volatile("movl %%cr0,%0" : "=r" (data));
478 	return (data);
479 }
480 
481 static __inline u_int
482 rcr2(void)
483 {
484 	u_int	data;
485 
486 	__asm __volatile("movl %%cr2,%0" : "=r" (data));
487 	return (data);
488 }
489 
490 static __inline void
491 load_cr3(u_int data)
492 {
493 
494 	__asm __volatile("movl %0,%%cr3" : : "r" (data) : "memory");
495 }
496 
497 static __inline u_int
498 rcr3(void)
499 {
500 	u_int	data;
501 
502 	__asm __volatile("movl %%cr3,%0" : "=r" (data));
503 	return (data);
504 }
505 
506 static __inline void
507 load_cr4(u_int data)
508 {
509 	__asm __volatile("movl %0,%%cr4" : : "r" (data));
510 }
511 
512 static __inline u_int
513 rcr4(void)
514 {
515 	u_int	data;
516 
517 	__asm __volatile("movl %%cr4,%0" : "=r" (data));
518 	return (data);
519 }
520 
521 static __inline uint64_t
522 rxcr(u_int reg)
523 {
524 	u_int low, high;
525 
526 	__asm __volatile("xgetbv" : "=a" (low), "=d" (high) : "c" (reg));
527 	return (low | ((uint64_t)high << 32));
528 }
529 
530 static __inline void
531 load_xcr(u_int reg, uint64_t val)
532 {
533 	u_int low, high;
534 
535 	low = val;
536 	high = val >> 32;
537 	__asm __volatile("xsetbv" : : "c" (reg), "a" (low), "d" (high));
538 }
539 
540 /*
541  * Global TLB flush (except for thise for pages marked PG_G)
542  */
543 static __inline void
544 invltlb(void)
545 {
546 
547 	load_cr3(rcr3());
548 }
549 
550 /*
551  * TLB flush for an individual page (even if it has PG_G).
552  * Only works on 486+ CPUs (i386 does not have PG_G).
553  */
554 static __inline void
555 invlpg(u_int addr)
556 {
557 
558 	__asm __volatile("invlpg %0" : : "m" (*(char *)addr) : "memory");
559 }
560 
561 static __inline u_short
562 rfs(void)
563 {
564 	u_short sel;
565 	__asm __volatile("movw %%fs,%0" : "=rm" (sel));
566 	return (sel);
567 }
568 
569 static __inline uint64_t
570 rgdt(void)
571 {
572 	uint64_t gdtr;
573 	__asm __volatile("sgdt %0" : "=m" (gdtr));
574 	return (gdtr);
575 }
576 
577 static __inline u_short
578 rgs(void)
579 {
580 	u_short sel;
581 	__asm __volatile("movw %%gs,%0" : "=rm" (sel));
582 	return (sel);
583 }
584 
585 static __inline uint64_t
586 ridt(void)
587 {
588 	uint64_t idtr;
589 	__asm __volatile("sidt %0" : "=m" (idtr));
590 	return (idtr);
591 }
592 
593 static __inline u_short
594 rldt(void)
595 {
596 	u_short ldtr;
597 	__asm __volatile("sldt %0" : "=g" (ldtr));
598 	return (ldtr);
599 }
600 
601 static __inline u_short
602 rss(void)
603 {
604 	u_short sel;
605 	__asm __volatile("movw %%ss,%0" : "=rm" (sel));
606 	return (sel);
607 }
608 
609 static __inline u_short
610 rtr(void)
611 {
612 	u_short tr;
613 	__asm __volatile("str %0" : "=g" (tr));
614 	return (tr);
615 }
616 
617 static __inline void
618 load_fs(u_short sel)
619 {
620 	__asm __volatile("movw %0,%%fs" : : "rm" (sel));
621 }
622 
623 static __inline void
624 load_gs(u_short sel)
625 {
626 	__asm __volatile("movw %0,%%gs" : : "rm" (sel));
627 }
628 
629 static __inline void
630 lidt(struct region_descriptor *addr)
631 {
632 	__asm __volatile("lidt (%0)" : : "r" (addr));
633 }
634 
635 static __inline void
636 lldt(u_short sel)
637 {
638 	__asm __volatile("lldt %0" : : "r" (sel));
639 }
640 
641 static __inline void
642 ltr(u_short sel)
643 {
644 	__asm __volatile("ltr %0" : : "r" (sel));
645 }
646 
647 static __inline u_int
648 rdr0(void)
649 {
650 	u_int	data;
651 	__asm __volatile("movl %%dr0,%0" : "=r" (data));
652 	return (data);
653 }
654 
655 static __inline void
656 load_dr0(u_int dr0)
657 {
658 	__asm __volatile("movl %0,%%dr0" : : "r" (dr0));
659 }
660 
661 static __inline u_int
662 rdr1(void)
663 {
664 	u_int	data;
665 	__asm __volatile("movl %%dr1,%0" : "=r" (data));
666 	return (data);
667 }
668 
669 static __inline void
670 load_dr1(u_int dr1)
671 {
672 	__asm __volatile("movl %0,%%dr1" : : "r" (dr1));
673 }
674 
675 static __inline u_int
676 rdr2(void)
677 {
678 	u_int	data;
679 	__asm __volatile("movl %%dr2,%0" : "=r" (data));
680 	return (data);
681 }
682 
683 static __inline void
684 load_dr2(u_int dr2)
685 {
686 	__asm __volatile("movl %0,%%dr2" : : "r" (dr2));
687 }
688 
689 static __inline u_int
690 rdr3(void)
691 {
692 	u_int	data;
693 	__asm __volatile("movl %%dr3,%0" : "=r" (data));
694 	return (data);
695 }
696 
697 static __inline void
698 load_dr3(u_int dr3)
699 {
700 	__asm __volatile("movl %0,%%dr3" : : "r" (dr3));
701 }
702 
703 static __inline u_int
704 rdr6(void)
705 {
706 	u_int	data;
707 	__asm __volatile("movl %%dr6,%0" : "=r" (data));
708 	return (data);
709 }
710 
711 static __inline void
712 load_dr6(u_int dr6)
713 {
714 	__asm __volatile("movl %0,%%dr6" : : "r" (dr6));
715 }
716 
717 static __inline u_int
718 rdr7(void)
719 {
720 	u_int	data;
721 	__asm __volatile("movl %%dr7,%0" : "=r" (data));
722 	return (data);
723 }
724 
725 static __inline void
726 load_dr7(u_int dr7)
727 {
728 	__asm __volatile("movl %0,%%dr7" : : "r" (dr7));
729 }
730 
731 static __inline u_char
732 read_cyrix_reg(u_char reg)
733 {
734 	outb(0x22, reg);
735 	return inb(0x23);
736 }
737 
738 static __inline void
739 write_cyrix_reg(u_char reg, u_char data)
740 {
741 	outb(0x22, reg);
742 	outb(0x23, data);
743 }
744 
745 static __inline register_t
746 intr_disable(void)
747 {
748 	register_t eflags;
749 
750 	eflags = read_eflags();
751 	disable_intr();
752 	return (eflags);
753 }
754 
755 static __inline void
756 intr_restore(register_t eflags)
757 {
758 	write_eflags(eflags);
759 }
760 
761 static __inline uint32_t
762 rdpkru(void)
763 {
764 	uint32_t res;
765 
766 	__asm __volatile("rdpkru" :  "=a" (res) : "c" (0) : "edx");
767 	return (res);
768 }
769 
770 static __inline void
771 wrpkru(uint32_t mask)
772 {
773 
774 	__asm __volatile("wrpkru" :  : "a" (mask),  "c" (0), "d" (0));
775 }
776 
777 #else /* !(__GNUCLIKE_ASM && __CC_SUPPORTS___INLINE) */
778 
779 int	breakpoint(void);
780 u_int	bsfl(u_int mask);
781 u_int	bsrl(u_int mask);
782 void	clflush(u_long addr);
783 void	clts(void);
784 void	cpuid_count(u_int ax, u_int cx, u_int *p);
785 void	disable_intr(void);
786 void	do_cpuid(u_int ax, u_int *p);
787 void	enable_intr(void);
788 void	halt(void);
789 void	ia32_pause(void);
790 u_char	inb(u_int port);
791 u_int	inl(u_int port);
792 void	insb(u_int port, void *addr, size_t count);
793 void	insl(u_int port, void *addr, size_t count);
794 void	insw(u_int port, void *addr, size_t count);
795 register_t	intr_disable(void);
796 void	intr_restore(register_t ef);
797 void	invd(void);
798 void	invlpg(u_int addr);
799 void	invltlb(void);
800 u_short	inw(u_int port);
801 void	lidt(struct region_descriptor *addr);
802 void	lldt(u_short sel);
803 void	load_cr0(u_int cr0);
804 void	load_cr3(u_int cr3);
805 void	load_cr4(u_int cr4);
806 void	load_dr0(u_int dr0);
807 void	load_dr1(u_int dr1);
808 void	load_dr2(u_int dr2);
809 void	load_dr3(u_int dr3);
810 void	load_dr6(u_int dr6);
811 void	load_dr7(u_int dr7);
812 void	load_fs(u_short sel);
813 void	load_gs(u_short sel);
814 void	ltr(u_short sel);
815 void	outb(u_int port, u_char data);
816 void	outl(u_int port, u_int data);
817 void	outsb(u_int port, const void *addr, size_t count);
818 void	outsl(u_int port, const void *addr, size_t count);
819 void	outsw(u_int port, const void *addr, size_t count);
820 void	outw(u_int port, u_short data);
821 u_int	rcr0(void);
822 u_int	rcr2(void);
823 u_int	rcr3(void);
824 u_int	rcr4(void);
825 uint64_t rdmsr(u_int msr);
826 uint64_t rdpmc(u_int pmc);
827 u_int	rdr0(void);
828 u_int	rdr1(void);
829 u_int	rdr2(void);
830 u_int	rdr3(void);
831 u_int	rdr6(void);
832 u_int	rdr7(void);
833 uint64_t rdtsc(void);
834 u_char	read_cyrix_reg(u_char reg);
835 u_int	read_eflags(void);
836 u_int	rfs(void);
837 uint64_t rgdt(void);
838 u_int	rgs(void);
839 uint64_t ridt(void);
840 u_short	rldt(void);
841 u_short	rtr(void);
842 void	wbinvd(void);
843 void	write_cyrix_reg(u_char reg, u_char data);
844 void	write_eflags(u_int ef);
845 void	wrmsr(u_int msr, uint64_t newval);
846 
847 #endif	/* __GNUCLIKE_ASM && __CC_SUPPORTS___INLINE */
848 
849 void    reset_dbregs(void);
850 
851 #ifdef _KERNEL
852 int	rdmsr_safe(u_int msr, uint64_t *val);
853 int	wrmsr_safe(u_int msr, uint64_t newval);
854 #endif
855 
856 #endif /* !_MACHINE_CPUFUNC_H_ */
857