diff options
Diffstat (limited to 'arch/arm/lib/call_with_stack.S')
| -rw-r--r-- | arch/arm/lib/call_with_stack.S | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/arch/arm/lib/call_with_stack.S b/arch/arm/lib/call_with_stack.S new file mode 100644 index 000000000..28b0341ae --- /dev/null +++ b/arch/arm/lib/call_with_stack.S @@ -0,0 +1,32 @@ +/* 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) |