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 *)(¤t->thread.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 int *user_registers asm("sl"); 33 34 #define GET_USERREG() (user_registers) 35 36 /* Need task_struct */ 37 #include <linux/sched.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 resetFPA11(void); 90 extern void SetRoundingMode(const unsigned int); 91 extern void SetRoundingPrecision(const unsigned int); 92 93 #endif 94