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 __FPSR_H__
23#define __FPSR_H__
24
25/*
26The FPSR is a 32 bit register consisting of 4 parts, each exactly
27one byte.
28
29	SYSTEM ID
30	EXCEPTION TRAP ENABLE BYTE
31	SYSTEM CONTROL BYTE
32	CUMULATIVE EXCEPTION FLAGS BYTE
33
34The FPCR is a 32 bit register consisting of bit flags.
35*/
36
37/* SYSTEM ID
38------------
39Note: the system id byte is read only  */
40
41typedef unsigned int FPSR;  /* type for floating point status register */
42typedef unsigned int FPCR;  /* type for floating point control register */
43
44#define MASK_SYSID		0xff000000
45#define BIT_HARDWARE		0x80000000
46#define FP_EMULATOR		0x01000000	/* System ID for emulator */
47#define FP_ACCELERATOR		0x81000000	/* System ID for FPA11 */
48
49/* EXCEPTION TRAP ENABLE BYTE
50----------------------------- */
51
52#define MASK_TRAP_ENABLE	0x00ff0000
53#define MASK_TRAP_ENABLE_STRICT	0x001f0000
54#define BIT_IXE		0x00100000   /* inexact exception enable */
55#define BIT_UFE		0x00080000   /* underflow exception enable */
56#define BIT_OFE		0x00040000   /* overflow exception enable */
57#define BIT_DZE		0x00020000   /* divide by zero exception enable */
58#define BIT_IOE		0x00010000   /* invalid operation exception enable */
59
60/* SYSTEM CONTROL BYTE
61---------------------- */
62
63#define MASK_SYSTEM_CONTROL	0x0000ff00
64#define MASK_TRAP_STRICT	0x00001f00
65
66#define BIT_AC	0x00001000	/* use alternative C-flag definition
67				   for compares */
68#define BIT_EP	0x00000800	/* use expanded packed decimal format */
69#define BIT_SO	0x00000400	/* select synchronous operation of FPA */
70#define BIT_NE	0x00000200	/* NaN exception bit */
71#define BIT_ND	0x00000100	/* no denormalized numbers bit */
72
73/* CUMULATIVE EXCEPTION FLAGS BYTE
74---------------------------------- */
75
76#define MASK_EXCEPTION_FLAGS		0x000000ff
77#define MASK_EXCEPTION_FLAGS_STRICT	0x0000001f
78
79#define BIT_IXC		0x00000010	/* inexact exception flag */
80#define BIT_UFC		0x00000008	/* underflow exception flag */
81#define BIT_OFC		0x00000004	/* overfloat exception flag */
82#define BIT_DZC		0x00000002	/* divide by zero exception flag */
83#define BIT_IOC		0x00000001	/* invalid operation exception flag */
84
85/* Floating Point Control Register
86----------------------------------*/
87
88#define BIT_RU		0x80000000	/* rounded up bit */
89#define BIT_IE		0x10000000	/* inexact bit */
90#define BIT_MO		0x08000000	/* mantissa overflow bit */
91#define BIT_EO		0x04000000	/* exponent overflow bit */
92#define BIT_SB		0x00000800	/* store bounce */
93#define BIT_AB		0x00000400	/* arithmetic bounce */
94#define BIT_RE		0x00000200	/* rounding exception */
95#define BIT_DA		0x00000100	/* disable FPA */
96
97#define MASK_OP		0x00f08010	/* AU operation code */
98#define MASK_PR		0x00080080	/* AU precision */
99#define MASK_S1		0x00070000	/* AU source register 1 */
100#define MASK_S2		0x00000007	/* AU source register 2 */
101#define MASK_DS		0x00007000	/* AU destination register */
102#define MASK_RM		0x00000060	/* AU rounding mode */
103#define MASK_ALU	0x9cfff2ff	/* only ALU can write these bits */
104#define MASK_RESET	0x00000d00	/* bits set on reset, all others cleared */
105#define MASK_WFC	MASK_RESET
106#define MASK_RFC	~MASK_RESET
107
108#endif
109