xref: /freebsd/sys/amd64/include/cpufunc.h (revision 5b81b6b301437eb9a6df491c829475bd29ae5d6c)

/*
 * Functions to provide access to special i386 instructions.
 * XXX - bezillions more are defined in locore.s but are not declared anywhere.
 */

#include <sys/cdefs.h>
#include <sys/types.h>

#ifdef	__GNUC__

static __inline int bdb(void)
{
	extern int bdb_exists;

	if (!bdb_exists)
		return (0);
	__asm("int $3");
	return (1);
}

static __inline void
disable_intr(void)
{
	__asm __volatile("cli");
}

static __inline void
enable_intr(void)
{
	__asm __volatile("sti");
}

/*
 * This roundabout method of returning a u_char helps stop gcc-1.40 from
 * generating unnecessary movzbl's.
 */
#define	inb(port)	((u_char) u_int_inb(port))

static __inline u_int
u_int_inb(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-2.2.2 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 void
outb(u_int port, u_char data)
{
	register u_char	al asm("ax");

	al = data;		/* help gcc-1.40's register allocator */
	__asm __volatile("outb %0,%%dx" : : "a" (al), "d" (port));
}

#else /* not __GNUC__ */

int	bdb		__P((void));
void	disable_intr	__P((void));
void	enable_intr	__P((void));
u_char	inb		__P((u_int port));
void	outb		__P((u_int port, u_int data));	/* XXX - incompat */

#endif	/* __GNUC__ */

#define	really_u_int	int	/* XXX */
#define	really_void	int	/* XXX */

void	load_cr0	__P((u_int cr0));
really_u_int	rcr0	__P((void));

#ifdef notyet
really_void	setidt	__P((int idx, /*XXX*/caddr_t func, int typ, int dpl));
#endif

#undef	really_u_int
#undef	really_void