arch/arm/nwfpe/fpa11.h

   1 /*
   2     NetWinder Floating Point Emulator
   3     (c) Rebel.com, 1998-1999
   4
   5     Direct questions, comments to Scott Bambrough <scottb@netwinder.org>
   6
   7     This program is free software; you can redistribute it and/or modify
   8     it under the terms of the GNU General Public License as published by
   9     the Free Software Foundation; either version 2 of the License, or
  10     (at your option) any later version.
  11
  12     This program is distributed in the hope that it will be useful,
  13     but WITHOUT ANY WARRANTY; without even the implied warranty of
  14     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15     GNU General Public License for more details.
  16
  17     You should have received a copy of the GNU General Public License
  18     along with this program; if not, write to the Free Software
  19     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #ifndef __FPA11_H__
  23 #define __FPA11_H__
  24
  25 #define GET_FPA11() ((FPA11 *)(&current_thread_info()->fpstate))
  26
  27 /*
  28  * The processes registers are always at the very top of the 8K
  29  * stack+task struct.  Use the same method as 'current' uses to
  30  * reach them.
  31  */
  32 register unsigned long *user_registers asm("sl");
  33
  34 #define GET_USERREG() (user_registers)
  35
  36 #include <linux/config.h>
  37 #include <linux/thread_info.h>
  38
  39 /* includes */
  40 #include "fpsr.h"               /* FP control and status register definitions */
  41 #include "milieu.h"
  42 #include "softfloat.h"
  43
  44 #define         typeNone                0x00
  45 #define         typeSingle              0x01
  46 #define         typeDouble              0x02
  47 #define         typeExtended            0x03
  48
  49 /*
  50  * This must be no more and no less than 12 bytes.
  51  */
  52 typedef union tagFPREG {
  53         float32 fSingle;
  54         float64 fDouble;
  55 #ifdef CONFIG_FPE_NWFPE_XP
  56         floatx80 fExtended;
  57 #else
  58         int padding[3];
  59 #endif
  60 } FPREG;
  61
  62 /*
  63  * FPA11 device model.
  64  *
  65  * This structure is exported to user space.  Do not re-order.
  66  * Only add new stuff to the end, and do not change the size of
  67  * any element.  Elements of this structure are used by user
  68  * space, and must match struct user_fp in include/asm-arm/user.h.
  69  * We include the byte offsets below for documentation purposes.
  70  *
  71  * The size of this structure and FPREG are checked by fpmodule.c
  72  * on initialisation.  If the rules have been broken, NWFPE will
  73  * not initialise.
  74  */
  75 typedef struct tagFPA11 {
  76 /*   0 */ FPREG fpreg[8];       /* 8 floating point registers */
  77 /*  96 */ FPSR fpsr;            /* floating point status register */
  78 /* 100 */ FPCR fpcr;            /* floating point control register */
  79 /* 104 */ unsigned char fType[8];       /* type of floating point value held in
  80                                            floating point registers.  One of
  81                                            none, single, double or extended. */
  82 /* 112 */ int initflag;         /* this is special.  The kernel guarantees
  83                                    to set it to 0 when a thread is launched,
  84                                    so we can use it to detect whether this
  85                                    instance of the emulator needs to be
  86                                    initialised. */
  87 } FPA11;
  88
  89 extern void SetRoundingMode(const unsigned int);
  90 extern void SetRoundingPrecision(const unsigned int);
  91 extern void nwfpe_init_fpa(union fp_state *fp);
  92
  93 #endif