migrate_timers: add comment, use spinlock_irq()
[linux-2.6/mini2440.git] / include / asm-mips / fpu.h
blob8a3ef247659a79daefde386445eb4c7d8b6d7442
1 /*
2 * Copyright (C) 2002 MontaVista Software Inc.
3 * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version.
9 */
10 #ifndef _ASM_FPU_H
11 #define _ASM_FPU_H
13 #include <linux/sched.h>
14 #include <linux/thread_info.h>
15 #include <linux/bitops.h>
17 #include <asm/mipsregs.h>
18 #include <asm/cpu.h>
19 #include <asm/cpu-features.h>
20 #include <asm/hazards.h>
21 #include <asm/processor.h>
22 #include <asm/current.h>
24 #ifdef CONFIG_MIPS_MT_FPAFF
25 #include <asm/mips_mt.h>
26 #endif
28 struct sigcontext;
29 struct sigcontext32;
31 extern asmlinkage int (*save_fp_context)(struct sigcontext __user *sc);
32 extern asmlinkage int (*restore_fp_context)(struct sigcontext __user *sc);
34 extern asmlinkage int (*save_fp_context32)(struct sigcontext32 __user *sc);
35 extern asmlinkage int (*restore_fp_context32)(struct sigcontext32 __user *sc);
37 extern void fpu_emulator_init_fpu(void);
38 extern int fpu_emulator_save_context(struct sigcontext __user *sc);
39 extern int fpu_emulator_restore_context(struct sigcontext __user *sc);
40 extern void _init_fpu(void);
41 extern void _save_fp(struct task_struct *);
42 extern void _restore_fp(struct task_struct *);
44 #define __enable_fpu() \
45 do { \
46 set_c0_status(ST0_CU1); \
47 enable_fpu_hazard(); \
48 } while (0)
50 #define __disable_fpu() \
51 do { \
52 clear_c0_status(ST0_CU1); \
53 disable_fpu_hazard(); \
54 } while (0)
56 #define enable_fpu() \
57 do { \
58 if (cpu_has_fpu) \
59 __enable_fpu(); \
60 } while (0)
62 #define disable_fpu() \
63 do { \
64 if (cpu_has_fpu) \
65 __disable_fpu(); \
66 } while (0)
69 #define clear_fpu_owner() clear_thread_flag(TIF_USEDFPU)
71 static inline int __is_fpu_owner(void)
73 return test_thread_flag(TIF_USEDFPU);
76 static inline int is_fpu_owner(void)
78 return cpu_has_fpu && __is_fpu_owner();
81 static inline void __own_fpu(void)
83 __enable_fpu();
84 KSTK_STATUS(current) |= ST0_CU1;
85 set_thread_flag(TIF_USEDFPU);
88 static inline void own_fpu_inatomic(int restore)
90 if (cpu_has_fpu && !__is_fpu_owner()) {
91 __own_fpu();
92 if (restore)
93 _restore_fp(current);
97 static inline void own_fpu(int restore)
99 preempt_disable();
100 own_fpu_inatomic(restore);
101 preempt_enable();
104 static inline void lose_fpu(int save)
106 preempt_disable();
107 if (is_fpu_owner()) {
108 if (save)
109 _save_fp(current);
110 KSTK_STATUS(current) &= ~ST0_CU1;
111 clear_thread_flag(TIF_USEDFPU);
112 __disable_fpu();
114 preempt_enable();
117 static inline void init_fpu(void)
119 preempt_disable();
120 if (cpu_has_fpu) {
121 __own_fpu();
122 _init_fpu();
123 } else {
124 fpu_emulator_init_fpu();
126 preempt_enable();
129 static inline void save_fp(struct task_struct *tsk)
131 if (cpu_has_fpu)
132 _save_fp(tsk);
135 static inline void restore_fp(struct task_struct *tsk)
137 if (cpu_has_fpu)
138 _restore_fp(tsk);
141 static inline fpureg_t *get_fpu_regs(struct task_struct *tsk)
143 if (tsk == current) {
144 preempt_disable();
145 if (is_fpu_owner())
146 _save_fp(current);
147 preempt_enable();
150 return tsk->thread.fpu.fpr;
153 #endif /* _ASM_FPU_H */