xref: /freebsd/sys/i386/include/cpu.h (revision 5b8c74d59a0876cd55972c08fdcee5f75c92615a)
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  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	from: @(#)cpu.h	5.4 (Berkeley) 5/9/91
37  * $FreeBSD$
38  */
39 
40 #ifndef _MACHINE_CPU_H_
41 #define	_MACHINE_CPU_H_
42 
43 /*
44  * Definitions unique to i386 cpu support.
45  */
46 #include <machine/psl.h>
47 #include <machine/frame.h>
48 #include <machine/segments.h>
49 #include <machine/globals.h>
50 
51 /*
52  * definitions of cpu-dependent requirements
53  * referenced in generic code
54  */
55 #undef	COPY_SIGCODE		/* don't copy sigcode above user stack in exec */
56 
57 #define	cpu_exec(p)	/* nothing */
58 #define cpu_swapin(p)	/* nothing */
59 #define	cpu_getstack(p)			((p)->p_md.md_regs->tf_esp)
60 #define cpu_setstack(p, ap)		((p)->p_md.md_regs->tf_esp = (ap))
61 
62 #define	CLKF_USERMODE(framep) \
63 	((ISPL((framep)->cf_cs) == SEL_UPL) || (framep->cf_eflags & PSL_VM))
64 
65 #define CLKF_INTR(framep)	(curproc->p_intr_nesting_level >= 2)
66 #define	CLKF_PC(framep)		((framep)->cf_eip)
67 
68 /*
69  * astpending bits
70  */
71 #define	AST_PENDING	0x00000001
72 #define	AST_RESCHED	0x00000002
73 
74 /*
75  * Preempt the current process if in interrupt from user mode,
76  * or after the current trap/syscall if in system mode.
77  *
78  * XXX: if astpending is later changed to an |= here due to more flags being
79  * added, we will have an atomicy problem.  The type of atomicy we need is
80  * a non-locked orl.
81  */
82 #define	need_resched() do {						\
83 	PCPU_SET(astpending, AST_RESCHED|AST_PENDING);			\
84 } while (0)
85 #define	resched_wanted()	(PCPU_GET(astpending) & AST_RESCHED)
86 
87 /*
88  * Arrange to handle pending profiling ticks before returning to user mode.
89  *
90  * XXX this is now poorly named and implemented.  It used to handle only a
91  * single tick and the PS_OWEUPC flag served as a counter.  Now there is a
92  * counter in the proc table and flag isn't really necessary.
93  */
94 #define	need_proftick(p) do {						\
95 	mtx_enter(&sched_lock, MTX_SPIN);				\
96 	(p)->p_sflag |= PS_OWEUPC;					\
97 	mtx_exit(&sched_lock, MTX_SPIN);				\
98 	aston();							\
99 } while (0)
100 
101 /*
102  * Notify the current process (p) that it has a signal pending,
103  * process as soon as possible.
104  *
105  * XXX: aston() really needs to be an atomic (not locked, but an orl),
106  * in case need_resched() is set by an interrupt.  But with astpending a
107  * per-cpu variable this is not trivial to do efficiently.  For now we blow
108  * it off (asynchronous need_resched() conflicts are not critical).
109  */
110 #define	signotify(p)	aston()
111 #define	aston() do {							\
112 	PCPU_SET(astpending, PCPU_GET(astpending) | AST_PENDING);	\
113 } while (0)
114 #define astoff()
115 
116 /*
117  * CTL_MACHDEP definitions.
118  */
119 #define CPU_CONSDEV		1	/* dev_t: console terminal device */
120 #define	CPU_ADJKERNTZ		2	/* int:	timezone offset	(seconds) */
121 #define	CPU_DISRTCSET		3	/* int: disable resettodr() call */
122 #define CPU_BOOTINFO		4	/* struct: bootinfo */
123 #define	CPU_WALLCLOCK		5	/* int:	indicates wall CMOS clock */
124 #define	CPU_MAXID		6	/* number of valid machdep ids */
125 
126 #define CTL_MACHDEP_NAMES { \
127 	{ 0, 0 }, \
128 	{ "console_device", CTLTYPE_STRUCT }, \
129 	{ "adjkerntz", CTLTYPE_INT }, \
130 	{ "disable_rtc_set", CTLTYPE_INT }, \
131 	{ "bootinfo", CTLTYPE_STRUCT }, \
132 	{ "wall_cmos_clock", CTLTYPE_INT }, \
133 }
134 
135 #ifdef _KERNEL
136 extern char	btext[];
137 extern char	etext[];
138 
139 void	fork_trampoline __P((void));
140 
141 #if defined(I386_CPU) || defined(I486_CPU)
142 extern u_int   tsc_present;
143 #endif
144 
145 /*
146  * Return contents of in-cpu fast counter as a sort of "bogo-time"
147  * for non-critical timing.
148  */
149 static __inline u_int64_t
150 get_cyclecount(void)
151 {
152 #if defined(I386_CPU) || defined(I486_CPU)
153 	struct timespec tv;
154 
155 	if (!tsc_present) {
156 		nanotime(&tv);
157 		return (tv.tv_sec * (u_int64_t)1000000000 + tv.tv_nsec);
158 	}
159 #endif
160 	return (rdtsc());
161 }
162 
163 #endif
164 
165 #endif /* !_MACHINE_CPU_H_ */
166