freebsd-src/sys/i386/include/specialreg.h
1993-06-12 14:58:17 +00:00

68 lines
2.8 KiB
C

/*-
* Copyright (c) 1991 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.
*
* @(#)specialreg.h 7.1 (Berkeley) 5/9/91
*
* PATCHES MAGIC LEVEL PATCH THAT GOT US HERE
* -------------------- ----- ----------------------
* CURRENT PATCH LEVEL: 1 00154
* -------------------- ----- ----------------------
*
* 20 Apr 93 Bruce Evans New npx-0.5 code
*
*/
/*
* Bits in 386 special registers:
*/
#define CR0_PE 0x00000001 /* Protected mode Enable */
#define CR0_MP 0x00000002 /* "Math" Present (NPX or NPX emulator) */
#ifdef notused
#define CR0_EM 0x00000004 /* EMulate non-NPX coproc. (trap ESC only) */
#endif
#define CR0_TS 0x00000008 /* Task Switched (if MP, trap ESC and WAIT) */
#ifdef notused
#define CR0_ET 0x00000010 /* Extension Type (387 (if set) vs 287) */
#endif
#define CR0_PG 0x80000000 /* PaGing enable */
/*
* Bits in 486 special registers:
*/
#define CR0_NE 0x00000020 /* Numeric Error enable (EX16 vs IRQ13) */
#define CR0_WP 0x00010000 /* Write Protect (honor ~PG_W in all modes) */
#ifdef notyet
#define CR0_AM 0x00040000 /* Alignment Mask (set to enable AC flag) */
#endif