text: /*-
   * 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 1.59.2.2 1998/05/06 19:06:37 gibbs 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>
  
  #ifdef	__GNUC__
  
  static __inline void
  breakpoint(void)
  {
  	__asm __volatile("int $3");
  }
  
  static __inline void
  disable_intr(void)
  {
  	__asm __volatile("cli" : : : "memory");
  }
  
  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);
  }
  
  #define	HAVE_INLINE_FLS
  
  static __inline int
  fls(int mask)
  {
  	int	result;
  	__asm __volatile("testl %0,%0; je 1f; bsrl %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 */
  
  /*
   * The following complications are to get around gcc not having a
   * constraint letter for the range 0..255.  We still put "d" in the
   * constraint because "i" isn't a valid constraint when the port
   * isn't constant.  This only matters for -O0 because otherwise
   * the non-working version gets optimized away.
   * 
   * 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)".
   *
   * The unnecessary test `(port) < 0x10000' is to generate a warning if
   * the `port' has type u_short or smaller.  Such types are pessimal.
   * This actually only works for signed types.  The range check is
   * careful to avoid generating warnings.
   */
  #define	inb(port) __extension__ ({					\
  	u_char	_data;							\
  	if (__builtin_constant_p(port) && ((port) & 0xffff) < 0x100	\
  	    && (port) < 0x10000)					\
  		_data = inbc(port);					\
  	else								\
  		_data = inbv(port);					\
  	_data; })
  
  #define	outb(port, data) (						\
  	__builtin_constant_p(port) && ((port) & 0xffff) < 0x100		\
  	&& (port) < 0x10000						\
  	? outbc(port, data) : outbv(port, data))
  
  static __inline u_char
  inbc(u_int port)
  {
  	u_char	data;
  
  	__asm __volatile("inb %1,%0" : "=a" (data) : "id" ((u_short)(port)));
  	return (data);
  }
  
  static __inline void
  outbc(u_int port, u_char data)
  {
  	__asm __volatile("outb %0,%1" : : "a" (data), "id" ((u_short)(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 void
  invd(void)
  {
  	__asm __volatile("invd");
  }
  
  static __inline void
  invlpg(u_int addr)
  {
  	__asm __volatile("invlpg (%0)" : : "r" (addr) : "memory");
  }
  
  static __inline void
  invltlb(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)
  			 : : "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 u_int
  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, const 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, const 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, const 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 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 quad_t
  rdmsr(u_int msr)
  {
  	quad_t rv;
  
  	__asm __volatile(".byte 0x0f, 0x32" : "=A" (rv) : "c" (msr));
  	return (rv);
  }
  
  static __inline quad_t
  rdpmc(u_int pmc)
  {
  	quad_t rv;
  
  	__asm __volatile(".byte 0x0f, 0x33" : "=A" (rv) : "c" (pmc));
  	return (rv);
  }
  
  static __inline quad_t
  rdtsc(void)
  {
  	quad_t rv;
  
  	__asm __volatile(".byte 0x0f, 0x31" : "=A" (rv));
  	return (rv);
  }
  
  static __inline void
  setbits(volatile unsigned *addr, u_int bits)
  {
  	__asm __volatile("orl %1,%0" : "=m" (*addr) : "ir" (bits));
  }
  
  static __inline void
  wbinvd(void)
  {
  	__asm __volatile("wbinvd");
  }
  
  static __inline void
  write_eflags(u_long ef)
  {
  	__asm __volatile("pushl %0; popfl" : : "r" (ef));
  }
  
  static __inline void
  wrmsr(u_int msr, quad_t newval)
  {
  	__asm __volatile(".byte 0x0f, 0x30" : : "A" (newval), "c" (msr));
  }
  
  #else /* !__GNUC__ */
  
  int	breakpoint	__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));
  void	invd		__P((void));
  void	invlpg		__P((u_int addr));
  void	invltlb		__P((void));
  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));
  u_long	rcr2		__P((void));
  quad_t	rdmsr		__P((u_int msr));
  quad_t	rdpmc		__P((u_int pmc));
  quad_t	rdtsc		__P((void));
  u_long	read_eflags	__P((void));
  void	setbits		__P((volatile unsigned *addr, u_int bits));
  void	wbinvd		__P((void));
  void	write_eflags	__P((u_long ef));
  void	wrmsr		__P((u_int msr, quad_t newval));
  
  #endif	/* __GNUC__ */
  
  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));
  
  #include <machine/spl.h>	/* XXX belongs elsewhere */
  
  #endif /* !_MACHINE_CPUFUNC_H_ */
  