/* 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
mfcr a3, epc
addi a3, TRAP0_SIZE
subi sp, 8
stw a3, (sp, 0)
mfcr a3, epsr
stw a3, (sp, 4)
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
1:
ldw a3, (a2)
cmpne a0, a3
bt16 3f
2:
stw a1, (a2)
3:
#endif
mvc a0
ldw a3, (sp, 0)
mtcr a3, epc
ldw a3, (sp, 4)
mtcr a3, epsr
addi sp, 8
KSPTOUSP
rte
END(csky_cmpxchg)
#ifndef CONFIG_CPU_HAS_LDSTEX
/*
* Called from tlbmodified exception
*/
ENTRY(csky_cmpxchg_fixup)
mfcr a0, epc
lrw a1, 2b
cmpne a1, a0
bt 1f
subi a1, (2b - 1b)
stw a1, (sp, LSAVE_PC)
1:
rts
END(csky_cmpxchg_fixup)
#endif
