freebsd-dev/sys/amd64/include/cpufunc.h
Bruce Evans 0ee893eb32 Add loadandclear(). It atomically loads a value from memory, clears the
value in memory and returns the original value.
1995-05-11 07:24:35 +00:00

446 lines
12 KiB
C

/*-
* Copyright (c) 1993 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $Id: cpufunc.h,v 1.34 1995/03/03 22:14:42 davidg Exp $
*/
/*
* Functions to provide access to special i386 instructions.
*/
#ifndef _MACHINE_CPUFUNC_H_
#define _MACHINE_CPUFUNC_H_
#include <sys/cdefs.h>
#include <sys/types.h>
#include <machine/spl.h> /* XXX belongs elsewhere */
#ifdef __GNUC__
#ifdef BDE_DEBUGGER
extern int bdb_exists;
static __inline int
bdb(void)
{
if (!bdb_exists)
return (0);
__asm __volatile("int $3");
return (1);
}
#endif /* BDE_DEBUGGER */
static __inline void
disable_intr(void)
{
__asm __volatile("cli");
}
static __inline void
enable_intr(void)
{
__asm __volatile("sti");
}
#define HAVE_INLINE_FFS
static __inline int
ffs(int mask)
{
int result;
/*
* bsfl turns out to be not all that slow on 486's. It can beaten
* using a binary search to reduce to 4 bits and then a table lookup,
* but only if the code is inlined and in the cache, and the code
* is quite large so inlining it probably busts the cache.
*
* Note that gcc-2's builtin ffs would be used if we didn't declare
* this inline or turn off the builtin. The builtin is faster but
* broken in gcc-2.4.5 and slower but working in gcc-2.5 and 2.6.
*/
__asm __volatile("testl %0,%0; je 1f; bsfl %0,%0; incl %0; 1:"
: "=r" (result) : "0" (mask));
return (result);
}
#if __GNUC__ < 2
#define inb(port) inbv(port)
#define outb(port, data) outbv(port, data)
#else /* __GNUC >= 2 */
/*
* Use an expression-statement instead of a conditional expression
* because gcc-2.6.0 would promote the operands of the conditional
* and produce poor code for "if ((inb(var) & const1) == const2)".
*/
#define inb(port) ({ \
u_char _data; \
if (__builtin_constant_p((int) (port)) && (port) < 256ul) \
_data = inbc(port); \
else \
_data = inbv(port); \
_data; })
#define outb(port, data) \
(__builtin_constant_p((int) (port)) && (port) < 256ul \
? outbc(port, data) : outbv(port, data))
static __inline u_char
inbc(u_int port)
{
u_char data;
__asm __volatile("inb %1,%0" : "=a" (data) : "i" (port));
return (data);
}
static __inline void
outbc(u_int port, u_char data)
{
__asm __volatile("outb %0,%1" : : "a" (data), "i" (port));
}
#endif /* __GNUC <= 2 */
static __inline u_char
inbv(u_int port)
{
u_char data;
/*
* We use %%dx and not %1 here because i/o is done at %dx and not at
* %edx, while gcc generates inferior code (movw instead of movl)
* if we tell it to load (u_short) port.
*/
__asm __volatile("inb %%dx,%0" : "=a" (data) : "d" (port));
return (data);
}
static __inline u_long
inl(u_int port)
{
u_long data;
__asm __volatile("inl %%dx,%0" : "=a" (data) : "d" (port));
return (data);
}
static __inline void
insb(u_int port, void *addr, size_t cnt)
{
__asm __volatile("cld; rep; insb"
: : "d" (port), "D" (addr), "c" (cnt)
: "di", "cx", "memory");
}
static __inline void
insw(u_int port, void *addr, size_t cnt)
{
__asm __volatile("cld; rep; insw"
: : "d" (port), "D" (addr), "c" (cnt)
: "di", "cx", "memory");
}
static __inline void
insl(u_int port, void *addr, size_t cnt)
{
__asm __volatile("cld; rep; insl"
: : "d" (port), "D" (addr), "c" (cnt)
: "di", "cx", "memory");
}
static __inline u_short
inw(u_int port)
{
u_short data;
__asm __volatile("inw %%dx,%0" : "=a" (data) : "d" (port));
return (data);
}
static __inline unsigned
loadandclear(u_int *addr)
{
u_int result;
__asm __volatile("xorl %0,%0; xchgl %1,%0"
: "=r" (result) : "m" (*addr));
return (result);
}
static __inline void
outbv(u_int port, u_char data)
{
u_char al;
/*
* Use an unnecessary assignment to help gcc's register allocator.
* This make a large difference for gcc-1.40 and a tiny difference
* for gcc-2.6.0. For gcc-1.40, al had to be ``asm("ax")'' for
* best results. gcc-2.6.0 can't handle this.
*/
al = data;
__asm __volatile("outb %0,%%dx" : : "a" (al), "d" (port));
}
static __inline void
outl(u_int port, u_long data)
{
/*
* outl() and outw() aren't used much so we haven't looked at
* possible micro-optimizations such as the unnecessary
* assignment for them.
*/
__asm __volatile("outl %0,%%dx" : : "a" (data), "d" (port));
}
static __inline void
outsb(u_int port, void *addr, size_t cnt)
{
__asm __volatile("cld; rep; outsb"
: : "d" (port), "S" (addr), "c" (cnt)
: "si", "cx");
}
static __inline void
outsw(u_int port, void *addr, size_t cnt)
{
__asm __volatile("cld; rep; outsw"
: : "d" (port), "S" (addr), "c" (cnt)
: "si", "cx");
}
static __inline void
outsl(u_int port, void *addr, size_t cnt)
{
__asm __volatile("cld; rep; outsl"
: : "d" (port), "S" (addr), "c" (cnt)
: "si", "cx");
}
static __inline void
outw(u_int port, u_short data)
{
__asm __volatile("outw %0,%%dx" : : "a" (data), "d" (port));
}
static __inline void
pmap_update(void)
{
u_long temp;
/*
* This should be implemented as load_cr3(rcr3()) when load_cr3()
* is inlined.
*/
__asm __volatile("movl %%cr3, %0; movl %0, %%cr3" : "=r" (temp));
}
static __inline u_long
rcr2(void)
{
u_long data;
__asm __volatile("movl %%cr2,%0" : "=r" (data));
return (data);
}
static __inline u_long
read_eflags(void)
{
u_long ef;
__asm __volatile("pushfl; popl %0" : "=r" (ef));
return (ef);
}
static __inline void
write_eflags(u_long ef)
{
__asm __volatile("pushl %0; popfl" : : "r" (ef));
}
/*
* XXX queue stuff belongs elsewhere.
*/
struct quehead {
struct quehead *qh_link;
struct quehead *qh_rlink;
};
static __inline void
insque(void *a, void *b)
{
struct quehead *element = a, *head = b;
element->qh_link = head->qh_link;
element->qh_rlink = head;
head->qh_link = element;
element->qh_link->qh_rlink = element;
}
static __inline void
remque(void *a)
{
struct quehead *element = a;
element->qh_link->qh_rlink = element->qh_rlink;
element->qh_rlink->qh_link = element->qh_link;
element->qh_rlink = 0;
}
#else /* !__GNUC__ */
int bdb __P((void));
void disable_intr __P((void));
void enable_intr __P((void));
u_char inb __P((u_int port));
u_long inl __P((u_int port));
void insb __P((u_int port, void *addr, size_t cnt));
void insl __P((u_int port, void *addr, size_t cnt));
void insw __P((u_int port, void *addr, size_t cnt));
u_short inw __P((u_int port));
u_int loadandclear __P((u_int *addr));
void outb __P((u_int port, u_char data));
void outl __P((u_int port, u_long data));
void outsb __P((u_int port, void *addr, size_t cnt));
void outsl __P((u_int port, void *addr, size_t cnt));
void outsw __P((u_int port, void *addr, size_t cnt));
void outw __P((u_int port, u_short data));
void pmap_update __P((void));
u_long read_eflags __P((void));
u_long rcr2 __P((void));
void write_eflags __P((u_long ef));
void insque __P((void *a, void *b));
void remque __P((void *a));
#endif /* __GNUC__ */
/*
* XXX the following declarations document garbage in support.s.
* gcc hasn't needed _divsi* for years.
* bcopy[bwx]() was used by pccons but isn't used now.
*/
int __divsi3 __P((int factor1, int factor2));
u_int __udivsi3 __P((u_int factor1, u_int factor2));
void bcopyb __P((const void *from, void *to, size_t len));
void bcopyw __P((const void *from, void *to, size_t len));
void bcopyx __P((const void *from, void *to, size_t len,
int stride));
#if 0
/*
* These functions in support.s are declared elsewhere.
*/
void bcopy __P((const void *from, void *to, size_t len));
void blkclr __P((void *buf, size_t len));
void bzero __P((void *buf, size_t len));
int copyin __P((void *udaddr, void *kaddr, size_t len));
int copyinstr __P((void *udaddr, void *kaddr, size_t len,
size_t *lencopied));
int copyout __P((void *kaddr, void *udaddr, size_t len));
int copystr __P((void *kfaddr, void *kdaddr, size_t len,
size_t *lencopied));
int fubyte __P((void *base));
int fuswintr __P((void *base));
int fuibyte __P((void *base));
int fuword __P((void *base));
struct region_descriptor;
void lgdt __P((struct region_descriptor *rdp));
void lidt __P((struct region_descriptor *rdp));
void lldt __P((u_short sel));
/*
* longjmp() and setjmp() are only used by ddb. They probably shouldn't
* shouldn't be supported in the kernel.
*/
#include <setjmp.h>
void longjmp __P((jmp_buf jb, int rv));
void ovbcopy __P((const void *from, void *to, size_t len);
int setjmp __P((jmp_buf jb));
struct soft_segment_descriptor;
union descriptor;
int ssdtosd __P((struct soft_segment_descriptor *ssdp,
union descriptor *sdp));
int subyte __P((void *base, int byte));
int suibyte __P((void *base, int byte));
int suswintr __P((void *base, int word));
int suword __P((void *base, int word));
/*
* These functions in support.s are declared elsewhere, but never used.
* A silly amount of effort went into copyoutstr(). It's not worth
* maintaining, since the string length is usually known so copyout
* works better, or is easy to find so copyout() can be used.
*/
int copyoutstr __P((void *kaddr, void *udaddr, size_t len,
size_t *lencopied));
int fuiword __P((void *base));
int suiword __P((void *base, int word));
/*
* These functions in support.s are also in libkern.a and are declared in
* libkern.h.
* ffs() is built in to gcc-2 and was buggy in gcc-2.4.5 so we may may the
* buggy version if we don't replace it by an inline.
*/
int bcmp __P((const void *b1, const void *b2, size_t length));
int ffs __P((int mask));
#endif /* 0 */
/*
* These variables and functions in support.s are used.
*/
extern u_int atdevbase; /* offset in virtual memory of ISA io mem */
void filli __P((int pat, void *base, size_t cnt));
void fillw __P((int /*u_short*/ pat, void *base, size_t cnt));
int fusword __P((void *base));
void load_cr0 __P((u_long cr0));
void load_cr3 __P((u_long cr3));
void ltr __P((u_short sel));
u_int rcr0 __P((void));
u_long rcr3 __P((void));
int rtcin __P((int val));
/*
* These functions are NOT in support.s and should be declared elsewhere.
*/
void Debugger __P((const char *msg));
u_long kvtop __P((void *addr));
typedef void alias_for_inthand_t __P((u_int cs, u_int ef, u_int esp,
u_int ss));
void setidt __P((int idx, alias_for_inthand_t *func, int typ,
int dpl));
#endif /* !_MACHINE_CPUFUNC_H_ */