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 #include <machine/globals.h> 49 50 /* Environment information of floating point unit */ 51 struct env87 { 52 long en_cw; /* control word (16bits) */ 53 long en_sw; /* status word (16bits) */ 54 long en_tw; /* tag word (16bits) */ 55 long en_fip; /* floating point instruction pointer */ 56 u_short en_fcs; /* floating code segment selector */ 57 u_short en_opcode; /* opcode last executed (11 bits ) */ 58 long en_foo; /* floating operand offset */ 59 long en_fos; /* floating operand segment selector */ 60 }; 61 62 /* Contents of each floating point accumulator */ 63 struct fpacc87 { 64 #ifdef dontdef /* too unportable */ 65 u_long fp_mantlo; /* mantissa low (31:0) */ 66 u_long fp_manthi; /* mantissa high (63:32) */ 67 int fp_exp:15; /* exponent */ 68 int fp_sgn:1; /* mantissa sign */ 69 #else 70 u_char fp_bytes[10]; 71 #endif 72 }; 73 74 /* Floating point context */ 75 struct save87 { 76 struct env87 sv_env; /* floating point control/status */ 77 struct fpacc87 sv_ac[8]; /* accumulator contents, 0-7 */ 78 u_long sv_ex_sw; /* status word for last exception */ 79 /* 80 * Bogus padding for emulators. Emulators should use their own 81 * struct and arrange to store into this struct (ending here) 82 * before it is inspected for ptracing or for core dumps. Some 83 * emulators overwrite the whole struct. We have no good way of 84 * knowing how much padding to leave. Leave just enough for the 85 * GPL emulator's i387_union (176 bytes total). 86 */ 87 u_char sv_pad[64]; /* padding; used by emulators */ 88 }; 89 90 /* 91 * The hardware default control word for i387's and later coprocessors is 92 * 0x37F, giving: 93 * 94 * round to nearest 95 * 64-bit precision 96 * all exceptions masked. 97 * 98 * We modify the affine mode bit and precision bits in this to give: 99 * 100 * affine mode for 287's (if they work at all) (1 in bitfield 1<<12) 101 * 53-bit precision (2 in bitfield 3<<8) 102 * 103 * 64-bit precision often gives bad results with high level languages 104 * because it makes the results of calculations depend on whether 105 * intermediate values are stored in memory or in FPU registers. 106 */ 107 #define __INITIAL_NPXCW__ 0x127F 108 109 #ifdef _KERNEL 110 #ifndef npxproc 111 extern struct proc *npxproc; 112 #endif 113 114 int npxdna __P((void)); 115 void npxexit __P((struct proc *p)); 116 void npxinit __P((int control)); 117 void npxsave __P((struct save87 *addr)); 118 #endif 119 120 #endif /* !_MACHINE_NPX_H_ */ 121