xref: /freebsd/sys/amd64/include/npx.h (revision ae83180158c4c937f170e31eff311b18c0286a93)
1 /*-
2  * Copyright (c) 1990 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * William Jolitz.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	from: @(#)npx.h	5.3 (Berkeley) 1/18/91
37  * $FreeBSD$
38  */
39 
40 /*
41  * 287/387 NPX Coprocessor Data Structures and Constants
42  * W. Jolitz 1/90
43  */
44 
45 #ifndef _MACHINE_NPX_H_
46 #define	_MACHINE_NPX_H_
47 
48 /* Environment information of floating point unit */
49 struct env87 {
50 	long	en_cw;		/* control word (16bits) */
51 	long	en_sw;		/* status word (16bits) */
52 	long	en_tw;		/* tag word (16bits) */
53 	long	en_fip;		/* floating point instruction pointer */
54 	u_short	en_fcs;		/* floating code segment selector */
55 	u_short	en_opcode;	/* opcode last executed (11 bits ) */
56 	long	en_foo;		/* floating operand offset */
57 	long	en_fos;		/* floating operand segment selector */
58 };
59 
60 /* Contents of each floating point accumulator */
61 struct fpacc87 {
62 #ifdef dontdef /* too unportable */
63 	u_long	fp_mantlo;	/* mantissa low (31:0) */
64 	u_long	fp_manthi;	/* mantissa high (63:32) */
65 	int	fp_exp:15;	/* exponent */
66 	int	fp_sgn:1;	/* mantissa sign */
67 #else
68 	u_char	fp_bytes[10];
69 #endif
70 };
71 
72 /* Floating point context */
73 struct save87 {
74 	struct	env87 sv_env;	/* floating point control/status */
75 	struct	fpacc87	sv_ac[8];	/* accumulator contents, 0-7 */
76 	u_long	sv_ex_sw;	/* status word for last exception */
77 	/*
78 	 * Bogus padding for emulators.  Emulators should use their own
79 	 * struct and arrange to store into this struct (ending here)
80 	 * before it is inspected for ptracing or for core dumps.  Some
81 	 * emulators overwrite the whole struct.  We have no good way of
82 	 * knowing how much padding to leave.  Leave just enough for the
83 	 * GPL emulator's i387_union (176 bytes total).
84 	 */
85 	u_char	sv_pad[64];	/* padding; used by emulators */
86 };
87 
88 struct  envxmm {
89 	u_int16_t	en_cw;		/* control word (16bits) */
90 	u_int16_t	en_sw;		/* status word (16bits) */
91 	u_int16_t	en_tw;		/* tag word (16bits) */
92 	u_int16_t	en_opcode;	/* opcode last executed (11 bits ) */
93 	u_int32_t	en_fip;		/* floating point instruction pointer */
94 	u_int16_t	en_fcs;		/* floating code segment selector */
95 	u_int16_t	en_pad0;	/* padding */
96 	u_int32_t	en_foo;		/* floating operand offset */
97 	u_int16_t	en_fos;		/* floating operand segment selector */
98 	u_int16_t	en_pad1;	/* padding */
99 	u_int32_t	en_mxcsr;	/* SSE sontorol/status register */
100 	u_int32_t	en_pad2;	/* padding */
101 };
102 
103 /* Contents of each SSE extended accumulator */
104 struct  xmmacc {
105 	u_char	xmm_bytes[16];
106 };
107 
108 struct  savexmm {
109 	struct	envxmm	sv_env;
110 	struct {
111 		struct fpacc87	fp_acc;
112 		u_char		fp_pad[6];      /* padding */
113 	} sv_fp[8];
114 	struct xmmacc	sv_xmm[8];
115 	u_long sv_ex_sw;	/* status word for last exception */
116 	u_char sv_pad[220];
117 } __attribute__((aligned(16)));
118 
119 union	savefpu {
120 	struct	save87	sv_87;
121 	struct	savexmm	sv_xmm;
122 };
123 
124 /*
125  * The hardware default control word for i387's and later coprocessors is
126  * 0x37F, giving:
127  *
128  *	round to nearest
129  *	64-bit precision
130  *	all exceptions masked.
131  *
132  * We modify the affine mode bit and precision bits in this to give:
133  *
134  *	affine mode for 287's (if they work at all) (1 in bitfield 1<<12)
135  *	53-bit precision (2 in bitfield 3<<8)
136  *
137  * 64-bit precision often gives bad results with high level languages
138  * because it makes the results of calculations depend on whether
139  * intermediate values are stored in memory or in FPU registers.
140  */
141 #define	__INITIAL_NPXCW__	0x127F
142 
143 #ifdef _KERNEL
144 int	npxdna(void);
145 void	npxexit(struct thread *td);
146 void	npxinit(int control);
147 void	npxsave(union savefpu *addr);
148 int	npxtrap(void);
149 #endif
150 
151 #endif /* !_MACHINE_NPX_H_ */
152