1 /* SPDX-License-Identifier: GPL-2.0 */
2 // Copyright (C) 2018 Hangzhou C-SKY Microsyst
3
4 #include <linux/linkage.h>
5 #include <abi/entry.h>
6
7 .text
8
9 /*
10 * int csky_cmpxchg(int oldval, int newval, in
11 *
12 * If *ptr != oldval && return 1,
13 * else *ptr = newval return 0.
14 */
15 ENTRY(csky_cmpxchg)
16 USPTOKSP
17
18 RD_MEH a3
19 WR_MEH a3
20
21 mfcr a3, epc
22 addi a3, TRAP0_SIZE
23
24 subi sp, 16
25 stw a3, (sp, 0)
26 mfcr a3, epsr
27 stw a3, (sp, 4)
28 mfcr a3, usp
29 stw a3, (sp, 8)
30
31 psrset ee
32 #ifdef CONFIG_CPU_HAS_LDSTEX
33 1:
34 ldex a3, (a2)
35 cmpne a0, a3
36 bt16 2f
37 mov a3, a1
38 stex a3, (a2)
39 bez a3, 1b
40 2:
41 sync.is
42 #else
43 GLOBAL(csky_cmpxchg_ldw)
44 ldw a3, (a2)
45 cmpne a0, a3
46 bt16 3f
47 GLOBAL(csky_cmpxchg_stw)
48 stw a1, (a2)
49 3:
50 #endif
51 mvc a0
52 ldw a3, (sp, 0)
53 mtcr a3, epc
54 ldw a3, (sp, 4)
55 mtcr a3, epsr
56 ldw a3, (sp, 8)
57 mtcr a3, usp
58 addi sp, 16
59 KSPTOUSP
60 rte
61 END(csky_cmpxchg)
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.