xref: /freebsd/sys/i386/include/cpu.h (revision 4b9d605768acabc460aa6dcfe8a1f8db35b16794)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1990 The Regents of the University of California.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * William Jolitz.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #ifndef _MACHINE_CPU_H_
36 #define	_MACHINE_CPU_H_
37 
38 /*
39  * Definitions unique to i386 cpu support.
40  */
41 #ifdef _KERNEL
42 #include <sys/systm.h>			/* For cpu_ticks(). */
43 #endif
44 #include <machine/psl.h>
45 #include <machine/frame.h>
46 #include <machine/segments.h>
47 
48 #define	cpu_exec(p)	/* nothing */
49 #define	cpu_swapin(p)	/* nothing */
50 #define	cpu_getstack(td)		((td)->td_frame->tf_esp)
51 #define	cpu_setstack(td, ap)		((td)->td_frame->tf_esp = (ap))
52 #define	cpu_spinwait()			ia32_pause()
53 
54 #define	TRAPF_USERMODE(framep) \
55 	((ISPL((framep)->tf_cs) == SEL_UPL) || ((framep)->tf_eflags & PSL_VM))
56 #define	TRAPF_PC(framep)	((framep)->tf_eip)
57 
58 #ifdef _KERNEL
59 /*
60  * Struct containing pointers to CPU management functions whose
61  * implementation is run time selectable.  Selection can be made,
62  * for example, based on detection of a particular CPU variant or
63  * hypervisor environment.
64  */
65 struct cpu_ops {
66 	void (*cpu_init)(void);
67 	void (*cpu_resume)(void);
68 };
69 
70 extern struct	cpu_ops cpu_ops;
71 extern char	btext[];
72 extern char	etext[];
73 
74 void	cpu_halt(void);
75 void	cpu_lock_delay(void);
76 void	cpu_reset(void);
77 void	fork_trampoline(void);
78 
79 /*
80  * Return contents of in-cpu fast counter as a sort of "bogo-time"
81  * for random-harvesting purposes.
82  */
83 static __inline uint64_t
84 get_cyclecount(void)
85 {
86 
87 	return (cpu_ticks());
88 }
89 
90 #endif
91 
92 #endif /* !_MACHINE_CPU_H_ */
93