/* SPDX-License-Identifier: GPL-2.0 */
// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
#include <linux/linkage.h>
#include <abi/entry.h>
.text
/*
* int csky_cmpxchg(int oldval, int newval, int *ptr)
*
* If *ptr != oldval && return 1,
* else *ptr = newval return 0.
*/
ENTRY(csky_cmpxchg)
USPTOKSP
RD_MEH a3
WR_MEH a3
mfcr a3, epc
addi a3, TRAP0_SIZE
subi sp, 16
stw a3, (sp, 0)
mfcr a3, epsr
stw a3, (sp, 4)
mfcr a3, usp
stw a3, (sp, 8)
psrset ee
#ifdef CONFIG_CPU_HAS_LDSTEX
1:
ldex a3, (a2)
cmpne a0, a3
bt16 2f
mov a3, a1
stex a3, (a2)
bez a3, 1b
2:
sync.is
#else
GLOBAL(csky_cmpxchg_ldw)
ldw a3, (a2)
cmpne a0, a3
bt16 3f
GLOBAL(csky_cmpxchg_stw)
stw a1, (a2)
3:
#endif
mvc a0
ldw a3, (sp, 0)
mtcr a3, epc
ldw a3, (sp, 4)
mtcr a3, epsr
ldw a3, (sp, 8)
mtcr a3, usp
addi sp, 16
KSPTOUSP
rte
END(csky_cmpxchg)
