/* MN10300 task switching definitions
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells ([email protected])
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
#ifndef _ASM_SWITCH_TO_H
#define _ASM_SWITCH_TO_H

#include <asm/barrier.h>

struct task_struct;
struct thread_struct;

#if !defined(CONFIG_LAZY_SAVE_FPU)
struct fpu_state_struct;
extern asmlinkage void fpu_save(struct fpu_state_struct *);
#define switch_fpu(prev, next) \
do { \
if ((prev)->thread.fpu_flags & THREAD_HAS_FPU) { \
(prev)->thread.fpu_flags &= ~THREAD_HAS_FPU; \
(prev)->thread.uregs->epsw &= ~EPSW_FE; \
fpu_save(&(prev)->thread.fpu_state); \
} \
} while (0)
#else
#define switch_fpu(prev, next) do {} while (0)
#endif

/* context switching is now performed out-of-line in switch_to.S */
extern asmlinkage
struct task_struct *__switch_to(struct thread_struct *prev,
struct thread_struct *next,
struct task_struct *prev_task);

#define switch_to(prev, next, last) \
do { \
switch_fpu(prev, next); \
current->thread.wchan = (u_long) __builtin_return_address(0); \
(last) = __switch_to(&(prev)->thread, &(next)->thread, (prev)); \
mb(); \
current->thread.wchan = 0; \
} while (0)

#endif /* _ASM_SWITCH_TO_H */