bsd_npx.h

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/*-
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * William Jolitz.
 *
 * 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.
 * 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.
 *
 *  from: @(#)npx.h 5.3 (Berkeley) 1/18/91
 * $FreeBSD: src/sys/i386/include/npx.h,v 1.29.2.1 2006/07/01 00:57:55 davidxu Exp $
 */
 
/*
 * 287/387 NPX Coprocessor Data Structures and Constants
 * W. Jolitz 1/90
 */
 
#ifndef _MACHINE_NPX_H_
#define _MACHINE_NPX_H_
 
/* Environment information of floating point unit */
struct env87 {
    long    en_cw;      /* control word (16bits) */
    long    en_sw;      /* status word (16bits) */
    long    en_tw;      /* tag word (16bits) */
    long    en_fip;     /* floating point instruction pointer */
    unsigned short  en_fcs;     /* floating code segment selector */
    unsigned short  en_opcode;  /* opcode last executed (11 bits ) */
    long    en_foo;     /* floating operand offset */
    long    en_fos;     /* floating operand segment selector */
};
 
/* Contents of each floating point accumulator */
struct fpacc87 {
#ifdef dontdef /* too unportable */
    unsigned long   fp_mantlo;  /* mantissa low (31:0) */
    unsigned long   fp_manthi;  /* mantissa high (63:32) */
    int fp_exp:15;  /* exponent */
    int fp_sgn:1;   /* mantissa sign */
#else
    unsigned char   fp_bytes[10];
#endif
};
 
/* Floating point context */
struct save87 {
    struct  env87 sv_env;   /* floating point control/status */
    struct  fpacc87 sv_ac[8];   /* accumulator contents, 0-7 */
    unsigned char   sv_pad0[4]; /* padding for (now unused) saved status word */
    /*
     * Bogus padding for emulators.  Emulators should use their own
     * struct and arrange to store into this struct (ending here)
     * before it is inspected for ptracing or for core dumps.  Some
     * emulators overwrite the whole struct.  We have no good way of
     * knowing how much padding to leave.  Leave just enough for the
     * GPL emulator's i387_union (176 bytes total).
     */
    unsigned char   sv_pad[64]; /* padding; used by emulators */
};
 
struct  envxmm {
    uint16_t    en_cw;      /* control word (16bits) */
    uint16_t    en_sw;      /* status word (16bits) */
    uint16_t    en_tw;      /* tag word (16bits) */
    uint16_t    en_opcode;  /* opcode last executed (11 bits ) */
    uint32_t    en_fip;     /* floating point instruction pointer */
    uint16_t    en_fcs;     /* floating code segment selector */
    uint16_t    en_pad0;    /* padding */
    uint32_t    en_foo;     /* floating operand offset */
    uint16_t    en_fos;     /* floating operand segment selector */
    uint16_t    en_pad1;    /* padding */
    uint32_t    en_mxcsr;   /* SSE sontorol/status register */
    uint32_t    en_mxcsr_mask;  /* valid bits in mxcsr */
};
 
/* Contents of each SSE extended accumulator */
struct  xmmacc {
    unsigned char   xmm_bytes[16];
};
 
struct  savexmm {
    struct  envxmm  sv_env;
    struct {
        struct fpacc87  fp_acc;
        unsigned char       fp_pad[6];      /* padding */
    } sv_fp[8];
    struct xmmacc   sv_xmm[8];
    unsigned char sv_pad[224];
#ifndef _MSC_BUILD
}  __attribute__((__aligned__(16)));
#else
} __declspec(align(16));
#endif // _MSC_BUILD
 
union   savefpu {
    struct  save87  sv_87;
    struct  savexmm sv_xmm;
};
 
/*
 * The hardware default control word for i387's and later coprocessors is
 * 0x37F, giving:
 *
 *  round to nearest
 *  64-bit precision
 *  all exceptions masked.
 *
 * We modify the affine mode bit and precision bits in this to give:
 *
 *  affine mode for 287's (if they work at all) (1 in bitfield 1<<12)
 *  53-bit precision (2 in bitfield 3<<8)
 *
 * 64-bit precision often gives bad results with high level languages
 * because it makes the results of calculations depend on whether
 * intermediate values are stored in memory or in FPU registers.
 */
#define __INITIAL_NPXCW__   0x127F
#define __INITIAL_MXCSR__   0x1F80
 
#ifdef _KERNEL
 
#define IO_NPX      0x0F0       /* Numeric Coprocessor */
#define IO_NPXSIZE  16      /* 80387/80487 NPX registers */
 
#define IRQ_NPX     13
 
/* full reset on some systems, NOP on others */
#define npx_full_reset() outb(IO_NPX + 1, 0)
 
int npxdna(void);
void    npxdrop(void);
void    npxexit(struct thread *td);
int npxformat(void);
int npxgetregs(struct thread *td, union savefpu *addr);
void    npxinit(unsigned short control);
void    npxsave(union savefpu *addr);
void    npxsetregs(struct thread *td, union savefpu *addr);
int npxtrap(void);
#endif
 
#endif /* !_MACHINE_NPX_H_ */