diff options
Diffstat (limited to 'arch/nios2/include/asm/switch_to.h')
| -rw-r--r-- | arch/nios2/include/asm/switch_to.h | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/arch/nios2/include/asm/switch_to.h b/arch/nios2/include/asm/switch_to.h new file mode 100644 index 000000000..c47b3f4af --- /dev/null +++ b/arch/nios2/include/asm/switch_to.h @@ -0,0 +1,31 @@ +/* + * Copyright (C) 2004 Microtronix Datacom Ltd. + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ +#ifndef _ASM_NIOS2_SWITCH_TO_H +#define _ASM_NIOS2_SWITCH_TO_H + +/* + * switch_to(n) should switch tasks to task ptr, first checking that + * ptr isn't the current task, in which case it does nothing. This + * also clears the TS-flag if the task we switched to has used the + * math co-processor latest. + */ +#define switch_to(prev, next, last) \ +{ \ + void *_last; \ + __asm__ __volatile__ ( \ + "mov r4, %1\n" \ + "mov r5, %2\n" \ + "call resume\n" \ + "mov %0,r4\n" \ + : "=r" (_last) \ + : "r" (prev), "r" (next) \ + : "r4", "r5", "r7", "r8", "ra"); \ + (last) = _last; \ +} + +#endif /* _ASM_NIOS2_SWITCH_TO_H */ |