call_with_stack.S
577 Bytes
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* arch/arm/lib/call_with_stack.S
*
* Copyright (C) 2011 ARM Ltd.
* Written by Will Deacon <will.deacon@arm.com>
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
/*
* void call_with_stack(void (*fn)(void *), void *arg, void *sp)
*
* Change the stack to that pointed at by sp, then invoke fn(arg) with
* the new stack.
*/
ENTRY(call_with_stack)
str sp, [r2, #-4]!
str lr, [r2, #-4]!
mov sp, r2
mov r2, r0
mov r0, r1
badr lr, 1f
ret r2
1: ldr lr, [sp]
ldr sp, [sp, #4]
ret lr
ENDPROC(call_with_stack)