xenocara/xserver/hw/xfree86/os-support/usl/usl_iop.c
2006-11-26 18:13:41 +00:00

108 lines
2.6 KiB
C

/*
* Copyright 2001,2005 by Kean Johnston <jkj@sco.com>
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
* the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation, and that the name Kean Johnston not be used in
* advertising or publicity pertaining to distribution of the software without
* specific, written prior permission. Kean Johnston makes no
* representations about the suitability of this software for any purpose.
* It is provided "as is" without express or implied warranty.
*
* KEAN JOHNSTON DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
* EVENT SHALL KEAN JOHNSTON BE LIABLE FOR ANY SPECIAL, INDIRECT OR
* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
* USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
* OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*/
/* $XConsortium$ */
#include "X.h"
#include "compiler.h"
#define _NEED_SYSI86
#include "xf86.h"
#include "xf86Priv.h"
#include "xf86OSpriv.h"
#include "xf86_OSlib.h"
/***************************************************************************/
/* I/O Permissions section */
/***************************************************************************/
static Bool IOEnabled = FALSE;
_X_EXPORT Bool
xf86EnableIO(void)
{
if (IOEnabled)
return TRUE;
if (sysi86(SI86IOPL, 3) < 0)
FatalError("Failed to set IOPL for extended I/O\n");
IOEnabled = TRUE;
return TRUE;
}
_X_EXPORT void
xf86DisableIO(void)
{
if (!IOEnabled)
return;
sysi86(SI86IOPL, 0);
IOEnabled = FALSE;
}
/***************************************************************************/
/* Interrupt Handling section */
/***************************************************************************/
_X_EXPORT Bool
xf86DisableInterrupts(void)
{
if (!IOEnabled) {
if (sysi86(SI86IOPL, 3) < 0)
return FALSE;
}
#ifdef __GNUC__
__asm__ __volatile__("cli");
#else
asm("cli");
#endif /* __GNUC__ */
if (!IOEnabled) {
sysi86(SI86IOPL, 0);
}
return(TRUE);
}
_X_EXPORT void
xf86EnableInterrupts(void)
{
if (!IOEnabled) {
if (sysi86(SI86IOPL, 3) < 0)
return;
}
#ifdef __GNUC__
__asm__ __volatile__("sti");
#else
asm("sti");
#endif /* __GNUC__ */
if (!IOEnabled) {
sysi86(SI86IOPL, 0);
}
}