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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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 */
Russell Kingb66da4a2005-07-17 10:54:50 +010032#define GET_USERREG() ((struct pt_regs *)(THREAD_START_SP + (unsigned long)current_thread_info()) - 1)
Linus Torvalds1da177e2005-04-16 15:20:36 -070033
34#include <linux/config.h>
35#include <linux/thread_info.h>
36
37/* includes */
38#include "fpsr.h" /* FP control and status register definitions */
39#include "milieu.h"
40#include "softfloat.h"
41
42#define typeNone 0x00
43#define typeSingle 0x01
44#define typeDouble 0x02
45#define typeExtended 0x03
46
47/*
48 * This must be no more and no less than 12 bytes.
49 */
50typedef union tagFPREG {
51 float32 fSingle;
52 float64 fDouble;
53#ifdef CONFIG_FPE_NWFPE_XP
54 floatx80 fExtended;
55#else
56 int padding[3];
57#endif
58} FPREG;
59
60/*
61 * FPA11 device model.
62 *
63 * This structure is exported to user space. Do not re-order.
64 * Only add new stuff to the end, and do not change the size of
65 * any element. Elements of this structure are used by user
66 * space, and must match struct user_fp in include/asm-arm/user.h.
67 * We include the byte offsets below for documentation purposes.
68 *
69 * The size of this structure and FPREG are checked by fpmodule.c
70 * on initialisation. If the rules have been broken, NWFPE will
71 * not initialise.
72 */
73typedef struct tagFPA11 {
74/* 0 */ FPREG fpreg[8]; /* 8 floating point registers */
75/* 96 */ FPSR fpsr; /* floating point status register */
76/* 100 */ FPCR fpcr; /* floating point control register */
77/* 104 */ unsigned char fType[8]; /* type of floating point value held in
78 floating point registers. One of
79 none, single, double or extended. */
80/* 112 */ int initflag; /* this is special. The kernel guarantees
81 to set it to 0 when a thread is launched,
82 so we can use it to detect whether this
83 instance of the emulator needs to be
84 initialised. */
85} FPA11;
86
87extern void SetRoundingMode(const unsigned int);
88extern void SetRoundingPrecision(const unsigned int);
89extern void nwfpe_init_fpa(union fp_state *fp);
90
91#endif