xref: /openbmc/qemu/linux-user/arm/nwfpe/fpa11.h (revision a719a27c)
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, see <http://www.gnu.org/licenses/>.
19 */
20 
21 #ifndef __FPA11_H__
22 #define __FPA11_H__
23 
24 #include <stdlib.h>
25 #include <stdio.h>
26 #include <errno.h>
27 
28 #include <cpu.h>
29 
30 #define GET_FPA11() (qemufpa)
31 
32 /*
33  * The processes registers are always at the very top of the 8K
34  * stack+task struct.  Use the same method as 'current' uses to
35  * reach them.
36  */
37 extern CPUARMState *user_registers;
38 
39 #define GET_USERREG() (user_registers)
40 
41 /* Need task_struct */
42 //#include <linux/sched.h>
43 
44 /* includes */
45 #include "fpsr.h"		/* FP control and status register definitions */
46 #include "fpu/softfloat.h"
47 
48 #define		typeNone		0x00
49 #define		typeSingle		0x01
50 #define		typeDouble		0x02
51 #define		typeExtended		0x03
52 
53 /*
54  * This must be no more and no less than 12 bytes.
55  */
56 typedef union tagFPREG {
57    floatx80 fExtended;
58    float64  fDouble;
59    float32  fSingle;
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 none
81 					   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     float_status fp_status;      /* QEMU float emulator status */
88 } FPA11;
89 
90 extern FPA11* qemufpa;
91 
92 void resetFPA11(void);
93 void SetRoundingMode(const unsigned int);
94 void SetRoundingPrecision(const unsigned int);
95 
96 static inline unsigned int readRegister(unsigned int reg)
97 {
98     return (user_registers->regs[(reg)]);
99 }
100 
101 static inline void writeRegister(unsigned int x, unsigned int y)
102 {
103 #if 0
104 	printf("writing %d to r%d\n",y,x);
105 #endif
106         user_registers->regs[(x)]=(y);
107 }
108 
109 static inline void writeConditionCodes(unsigned int x)
110 {
111         cpsr_write(user_registers,x,CPSR_NZCV);
112 }
113 
114 #define ARM_REG_PC 15
115 
116 unsigned int EmulateAll(unsigned int opcode, FPA11* qfpa, CPUARMState* qregs);
117 
118 unsigned int EmulateCPDO(const unsigned int);
119 unsigned int EmulateCPDT(const unsigned int);
120 unsigned int EmulateCPRT(const unsigned int);
121 
122 unsigned int SingleCPDO(const unsigned int opcode);
123 unsigned int DoubleCPDO(const unsigned int opcode);
124 unsigned int ExtendedCPDO(const unsigned int opcode);
125 
126 
127 /* included only for get_user/put_user macros */
128 #include "qemu.h"
129 
130 #endif
131