xref: /freebsd/sys/i386/include/cpu.h (revision eb14346a8ef95a5cf7f17d9cbb9832dde268ae9a)
1 /*-
2  * Copyright (c) 1990 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * William Jolitz.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 4. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  *	from: @(#)cpu.h	5.4 (Berkeley) 5/9/91
33  * $FreeBSD$
34  */
35 
36 #ifndef _MACHINE_CPU_H_
37 #define	_MACHINE_CPU_H_
38 
39 /*
40  * Definitions unique to i386 cpu support.
41  */
42 #include <machine/psl.h>
43 #include <machine/frame.h>
44 #include <machine/segments.h>
45 
46 #define	cpu_exec(p)	/* nothing */
47 #define	cpu_swapin(p)	/* nothing */
48 #define	cpu_getstack(td)		((td)->td_frame->tf_esp)
49 #define	cpu_setstack(td, ap)		((td)->td_frame->tf_esp = (ap))
50 #define	cpu_spinwait()			ia32_pause()
51 
52 #define	TRAPF_USERMODE(framep) \
53 	((ISPL((framep)->tf_cs) == SEL_UPL) || ((framep)->tf_eflags & PSL_VM))
54 #define	TRAPF_PC(framep)	((framep)->tf_eip)
55 
56 #ifdef _KERNEL
57 extern char	btext[];
58 extern char	etext[];
59 extern int	tsc_present;
60 
61 void	cpu_halt(void);
62 void	cpu_reset(void);
63 void	fork_trampoline(void);
64 void	swi_vm(void *);
65 
66 /*
67  * Return contents of in-cpu fast counter as a sort of "bogo-time"
68  * for random-harvesting purposes.
69  */
70 static __inline uint64_t
71 get_cyclecount(void)
72 {
73 #if defined(I486_CPU) || defined(KLD_MODULE)
74 	struct bintime bt;
75 
76 	if (!tsc_present) {
77 		binuptime(&bt);
78 		return ((uint64_t)bt.sec << 56 | bt.frac >> 8);
79 	}
80 #endif
81 	return (rdtsc());
82 }
83 
84 #endif
85 
86 #endif /* !_MACHINE_CPU_H_ */
87