fpa11.h

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/*
    NetWinder Floating Point Emulator
    (c) Rebel.com, 1998-1999
    
    Direct questions, comments to Scott Bambrough <[email protected]>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#ifndef __FPA11_H__
#define __FPA11_H__

#define GET_FPA11() ((FPA11 *)(&current_thread_info()->fpstate))

/*
 * The processes registers are always at the very top of the 8K
 * stack+task struct.  Use the same method as 'current' uses to
 * reach them.
 */
#define GET_USERREG() ((struct pt_regs *)(THREAD_START_SP + (unsigned long)current_thread_info()) - 1)

#include <linux/thread_info.h>

/* includes */
#include "fpsr.h"       /* FP control and status register definitions */
#include "milieu.h"

struct roundingData {
    int8 mode;
    int8 precision;
    signed char exception;
};

#include "softfloat.h"

#define     typeNone        0x00
#define     typeSingle      0x01
#define     typeDouble      0x02
#define     typeExtended        0x03

/*
 * This must be no more and no less than 12 bytes.
 */
typedef union tagFPREG {
    float32 fSingle;
    float64 fDouble;
#ifdef CONFIG_FPE_NWFPE_XP
    floatx80 fExtended;
#else
    u32 padding[3];
#endif
} __attribute__ ((packed,aligned(4))) FPREG;

/*
 * FPA11 device model.
 *
 * This structure is exported to user space.  Do not re-order.
 * Only add new stuff to the end, and do not change the size of
 * any element.  Elements of this structure are used by user
 * space, and must match struct user_fp in <asm/user.h>.
 * We include the byte offsets below for documentation purposes.
 *
 * The size of this structure and FPREG are checked by fpmodule.c
 * on initialisation.  If the rules have been broken, NWFPE will
 * not initialise.
 */
typedef struct tagFPA11 {
/*   0 */ FPREG fpreg[8];   /* 8 floating point registers */
/*  96 */ FPSR fpsr;        /* floating point status register */
/* 100 */ FPCR fpcr;        /* floating point control register */
/* 104 */ unsigned char fType[8];   /* type of floating point value held in
                       floating point registers.  One of
                       none, single, double or extended. */
/* 112 */ int initflag;     /* this is special.  The kernel guarantees
                   to set it to 0 when a thread is launched,
                   so we can use it to detect whether this
                   instance of the emulator needs to be
                   initialised. */
} __attribute__ ((packed,aligned(4))) FPA11;

extern int8 SetRoundingMode(const unsigned int);
extern int8 SetRoundingPrecision(const unsigned int);
extern void nwfpe_init_fpa(union fp_state *fp);

extern unsigned int EmulateAll(unsigned int opcode);

extern unsigned int EmulateCPDT(const unsigned int opcode);
extern unsigned int EmulateCPDO(const unsigned int opcode);
extern unsigned int EmulateCPRT(const unsigned int opcode);

/* fpa11_cpdt.c */
extern unsigned int PerformLDF(const unsigned int opcode);
extern unsigned int PerformSTF(const unsigned int opcode);
extern unsigned int PerformLFM(const unsigned int opcode);
extern unsigned int PerformSFM(const unsigned int opcode);

/* single_cpdo.c */

extern unsigned int SingleCPDO(struct roundingData *roundData,
                   const unsigned int opcode, FPREG * rFd);
/* double_cpdo.c */
extern unsigned int DoubleCPDO(struct roundingData *roundData,
                   const unsigned int opcode, FPREG * rFd);

/* extneded_cpdo.c */
extern unsigned int ExtendedCPDO(struct roundingData *roundData,
                 const unsigned int opcode, FPREG * rFd);

#endif