summaryrefslogtreecommitdiff
path: root/include/asm-mips/fpu.h
blob: 8bf510a27c643889f48476351ea8cc11d9a232ed (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
/*
 * Copyright (C) 2002 MontaVista Software Inc.
 * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 */
#ifndef _ASM_FPU_H
#define _ASM_FPU_H

#include <linux/config.h>
#include <linux/sched.h>
#include <linux/thread_info.h>

#include <asm/mipsregs.h>
#include <asm/cpu.h>
#include <asm/cpu-features.h>
#include <asm/bitops.h>
#include <asm/processor.h>
#include <asm/current.h>

#ifdef CONFIG_MIPS_MT_FPAFF
#include <asm/mips_mt.h>
#endif

struct sigcontext;
struct sigcontext32;

extern asmlinkage int (*save_fp_context)(struct sigcontext *sc);
extern asmlinkage int (*restore_fp_context)(struct sigcontext *sc);

extern asmlinkage int (*save_fp_context32)(struct sigcontext32 *sc);
extern asmlinkage int (*restore_fp_context32)(struct sigcontext32 *sc);

extern void fpu_emulator_init_fpu(void);
extern void _init_fpu(void);
extern void _save_fp(struct task_struct *);
extern void _restore_fp(struct task_struct *);

#if defined(CONFIG_CPU_SB1)
#define __enable_fpu_hazard()						\
do {									\
	asm(".set	push		\n\t"				\
	    ".set	mips64		\n\t"				\
	    ".set	noreorder	\n\t"				\
	    "ssnop			\n\t"				\
	    "bnezl	$0, .+4		\n\t"				\
	    "ssnop			\n\t"				\
	    ".set pop");						\
} while (0)
#else
#define __enable_fpu_hazard()						\
do {									\
	asm("nop;nop;nop;nop");		/* max. hazard */		\
} while (0)
#endif

#define __enable_fpu()							\
do {									\
        set_c0_status(ST0_CU1);						\
        __enable_fpu_hazard();						\
} while (0)

#define __disable_fpu()							\
do {									\
	clear_c0_status(ST0_CU1);					\
	/* We don't care about the c0 hazard here  */			\
} while (0)

#define enable_fpu()							\
do {									\
	if (cpu_has_fpu)						\
		__enable_fpu();						\
} while (0)

#define disable_fpu()							\
do {									\
	if (cpu_has_fpu)						\
		__disable_fpu();					\
} while (0)


#define clear_fpu_owner()	clear_thread_flag(TIF_USEDFPU)

static inline int __is_fpu_owner(void)
{
	return test_thread_flag(TIF_USEDFPU);
}

static inline int is_fpu_owner(void)
{
	return cpu_has_fpu && __is_fpu_owner();
}

static inline void own_fpu(void)
{
	if (cpu_has_fpu) {
		__enable_fpu();
		KSTK_STATUS(current) |= ST0_CU1;
		set_thread_flag(TIF_USEDFPU);
	}
}

static inline void lose_fpu(void)
{
	if (cpu_has_fpu) {
		KSTK_STATUS(current) &= ~ST0_CU1;
		clear_thread_flag(TIF_USEDFPU);
		__disable_fpu();
	}
}

static inline void init_fpu(void)
{
	if (cpu_has_fpu) {
		_init_fpu();
	} else {
		fpu_emulator_init_fpu();
	}
}

static inline void save_fp(struct task_struct *tsk)
{
	if (cpu_has_fpu)
		_save_fp(tsk);
}

static inline void restore_fp(struct task_struct *tsk)
{
	if (cpu_has_fpu)
		_restore_fp(tsk);
}

static inline fpureg_t *get_fpu_regs(struct task_struct *tsk)
{
	if (cpu_has_fpu) {
		if ((tsk == current) && __is_fpu_owner())
			_save_fp(current);
	}

	return tsk->thread.fpu.fpr;
}

#endif /* _ASM_FPU_H */