/*
* Copyright (C) 2002 MontaVista Software Inc.
* Author: Jun Sun, [email protected] or [email protected]
*
* 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/sched.h>
#include <linux/thread_info.h>
#include <linux/bitops.h>

#include <asm/mipsregs.h>
#include <asm/cpu.h>
#include <asm/cpu-features.h>
#include <asm/hazards.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 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 *);

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

#define __disable_fpu() \
do { \
clear_c0_status(ST0_CU1); \
disable_fpu_hazard(); \
} 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)
{
__enable_fpu();
KSTK_STATUS(current) |= ST0_CU1;
set_thread_flag(TIF_USEDFPU);
}

static inline void own_fpu_inatomic(int restore)
{
if (cpu_has_fpu && !__is_fpu_owner()) {
__own_fpu();
if (restore)
_restore_fp(current);
}
}

static inline void own_fpu(int restore)
{
preempt_disable();
own_fpu_inatomic(restore);
preempt_enable();
}

static inline void lose_fpu(int save)
{
preempt_disable();
if (is_fpu_owner()) {
if (save)
_save_fp(current);
KSTK_STATUS(current) &= ~ST0_CU1;
clear_thread_flag(TIF_USEDFPU);
__disable_fpu();
}
preempt_enable();
}

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

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 (tsk == current) {
preempt_disable();
if (is_fpu_owner())
_save_fp(current);
preempt_enable();
}

return tsk->thread.fpu.fpr;
}

#endif /* _ASM_FPU_H */