xref: /freebsd/sys/i386/include/cpu.h (revision 9a25c2363504942061c56d37499e99e3b1689be5)
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_setstack(p, ap)		((p)->p_md.md_regs[SP] = (ap))
60 
61 #define	CLKF_USERMODE(framep) \
62 	((ISPL((framep)->cf_cs) == SEL_UPL) || (framep->cf_eflags & PSL_VM))
63 
64 #define CLKF_INTR(framep)	(intr_nesting_level >= 2)
65 #define	CLKF_PC(framep)		((framep)->cf_eip)
66 
67 /*
68  * astpending bits
69  */
70 #define	AST_PENDING	0x00000001
71 #define	AST_RESCHED	0x00000002
72 
73 /*
74  * Preempt the current process if in interrupt from user mode,
75  * or after the current trap/syscall if in system mode.
76  *
77  * XXX: if astpending is later changed to an |= here due to more flags being
78  * added, we will have an atomicy problem.  The type of atomicy we need is
79  * a non-locked orl.
80  */
81 #define	need_resched() do {						\
82 	PCPU_SET(astpending, AST_RESCHED|AST_PENDING);			\
83 } while (0)
84 #define	resched_wanted()	(astpending & AST_RESCHED)
85 
86 /*
87  * Arrange to handle pending profiling ticks before returning to user mode.
88  *
89  * XXX this is now poorly named and implemented.  It used to handle only a
90  * single tick and the P_OWEUPC flag served as a counter.  Now there is a
91  * counter in the proc table and flag isn't really necessary.
92  */
93 #define	need_proftick(p) \
94 	do { (p)->p_flag |= P_OWEUPC; aston(); } while (0)
95 
96 /*
97  * Notify the current process (p) that it has a signal pending,
98  * process as soon as possible.
99  *
100  * XXX: aston() really needs to be an atomic (not locked, but an orl),
101  * in case need_resched() is set by an interrupt.  But with astpending a
102  * per-cpu variable this is not trivial to do efficiently.  For now we blow
103  * it off (asynchronous need_resched() conflicts are not critical).
104  */
105 #define	signotify(p)	aston()
106 #define	aston() do {							\
107 	PCPU_SET(astpending, astpending | AST_PENDING);			\
108 } while (0)
109 #define astoff()
110 
111 /*
112  * CTL_MACHDEP definitions.
113  */
114 #define CPU_CONSDEV		1	/* dev_t: console terminal device */
115 #define	CPU_ADJKERNTZ		2	/* int:	timezone offset	(seconds) */
116 #define	CPU_DISRTCSET		3	/* int: disable resettodr() call */
117 #define CPU_BOOTINFO		4	/* struct: bootinfo */
118 #define	CPU_WALLCLOCK		5	/* int:	indicates wall CMOS clock */
119 #define	CPU_MAXID		6	/* number of valid machdep ids */
120 
121 #define CTL_MACHDEP_NAMES { \
122 	{ 0, 0 }, \
123 	{ "console_device", CTLTYPE_STRUCT }, \
124 	{ "adjkerntz", CTLTYPE_INT }, \
125 	{ "disable_rtc_set", CTLTYPE_INT }, \
126 	{ "bootinfo", CTLTYPE_STRUCT }, \
127 	{ "wall_cmos_clock", CTLTYPE_INT }, \
128 }
129 
130 #ifdef _KERNEL
131 extern char	btext[];
132 extern char	etext[];
133 #ifndef intr_nesting_level
134 extern u_char	intr_nesting_level;
135 #endif
136 
137 void	fork_trampoline __P((void));
138 void	fork_return __P((struct proc *, struct trapframe));
139 #endif
140 
141 #endif /* !_MACHINE_CPU_H_ */
142