acrn-kernel/arch/avr32/kernel/switch_to.S

36 lines
914 B
ArmAsm

/*
* Copyright (C) 2004-2006 Atmel Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <asm/sysreg.h>
.text
.global __switch_to
.type __switch_to, @function
/* Switch thread context from "prev" to "next", returning "last"
* r12 : prev
* r11 : &prev->thread + 1
* r10 : &next->thread
*/
__switch_to:
stm --r11, r0,r1,r2,r3,r4,r5,r6,r7,sp,lr
mfsr r9, SYSREG_SR
st.w --r11, r9
ld.w r8, r10++
/*
* schedule() may have been called from a mode with a different
* set of registers. Make sure we don't lose anything here.
*/
pushm r10,r12
mtsr SYSREG_SR, r8
frs /* flush the return stack */
sub pc, -2 /* flush the pipeline */
popm r10,r12
ldm r10++, r0,r1,r2,r3,r4,r5,r6,r7,sp,pc
.size __switch_to, . - __switch_to