1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 NetWinder Floating Point Emulator 4 (c) Rebel.com, 1998-1999 5 6 Direct questions, comments to Scott Bambrough <scottb@netwinder.org> 7 8 */ 9 10 #ifndef __FPA11_H__ 11 #define __FPA11_H__ 12 13 #define GET_FPA11() ((FPA11 *)(¤t_thread_info()->fpstate)) 14 15 /* 16 * The processes registers are always at the very top of the 8K 17 * stack+task struct. Use the same method as 'current' uses to 18 * reach them. 19 */ 20 #define GET_USERREG() ((struct pt_regs *)(THREAD_START_SP + (unsigned long)current_thread_info()) - 1) 21 22 #include <linux/thread_info.h> 23 24 /* includes */ 25 #include "fpsr.h" /* FP control and status register definitions */ 26 #include "milieu.h" 27 28 struct roundingData { 29 int8 mode; 30 int8 precision; 31 signed char exception; 32 }; 33 34 #include "softfloat.h" 35 36 #define typeNone 0x00 37 #define typeSingle 0x01 38 #define typeDouble 0x02 39 #define typeExtended 0x03 40 41 /* 42 * This must be no more and no less than 12 bytes. 43 */ 44 typedef union tagFPREG { 45 float32 fSingle; 46 float64 fDouble; 47 #ifdef CONFIG_FPE_NWFPE_XP 48 floatx80 fExtended; 49 #else 50 u32 padding[3]; 51 #endif 52 } __attribute__ ((packed,aligned(4))) FPREG; 53 54 /* 55 * FPA11 device model. 56 * 57 * This structure is exported to user space. Do not re-order. 58 * Only add new stuff to the end, and do not change the size of 59 * any element. Elements of this structure are used by user 60 * space, and must match struct user_fp in <asm/user.h>. 61 * We include the byte offsets below for documentation purposes. 62 * 63 * The size of this structure and FPREG are checked by fpmodule.c 64 * on initialisation. If the rules have been broken, NWFPE will 65 * not initialise. 66 */ 67 typedef struct tagFPA11 { 68 /* 0 */ FPREG fpreg[8]; /* 8 floating point registers */ 69 /* 96 */ FPSR fpsr; /* floating point status register */ 70 /* 100 */ FPCR fpcr; /* floating point control register */ 71 /* 104 */ unsigned char fType[8]; /* type of floating point value held in 72 floating point registers. One of 73 none, single, double or extended. */ 74 /* 112 */ int initflag; /* this is special. The kernel guarantees 75 to set it to 0 when a thread is launched, 76 so we can use it to detect whether this 77 instance of the emulator needs to be 78 initialised. */ 79 } __attribute__ ((packed,aligned(4))) FPA11; 80 81 extern int8 SetRoundingMode(const unsigned int); 82 extern int8 SetRoundingPrecision(const unsigned int); 83 extern void nwfpe_init_fpa(union fp_state *fp); 84 85 extern unsigned int EmulateAll(unsigned int opcode); 86 87 extern unsigned int EmulateCPDT(const unsigned int opcode); 88 extern unsigned int EmulateCPDO(const unsigned int opcode); 89 extern unsigned int EmulateCPRT(const unsigned int opcode); 90 91 /* fpa11_cpdt.c */ 92 extern unsigned int PerformLDF(const unsigned int opcode); 93 extern unsigned int PerformSTF(const unsigned int opcode); 94 extern unsigned int PerformLFM(const unsigned int opcode); 95 extern unsigned int PerformSFM(const unsigned int opcode); 96 97 /* single_cpdo.c */ 98 99 extern unsigned int SingleCPDO(struct roundingData *roundData, 100 const unsigned int opcode, FPREG * rFd); 101 /* double_cpdo.c */ 102 extern unsigned int DoubleCPDO(struct roundingData *roundData, 103 const unsigned int opcode, FPREG * rFd); 104 105 /* extneded_cpdo.c */ 106 extern unsigned int ExtendedCPDO(struct roundingData *roundData, 107 const unsigned int opcode, FPREG * rFd); 108 109 #endif 110