1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ASM_SH_ATOMIC_LLSC_H
3 #define __ASM_SH_ATOMIC_LLSC_H
4
5 /*
6 * SH-4A note:
7 *
8 * We basically get atomic_xxx_return() for free compared with
9 * atomic_xxx(). movli.l/movco.l require r0 due to the instruction
10 * encoding, so the retval is automatically set without having to
11 * do any special work.
12 */
13 /*
14 * To get proper branch prediction for the main line, we must branch
15 * forward to code at the end of this object's .text section, then
16 * branch back to restart the operation.
17 */
18
19 #define ATOMIC_OP(op) \
20 static inline void atomic_##op(int i, atomic_t *v) \
21 { \
22 unsigned long tmp; \
23 \
24 __asm__ __volatile__ ( \
25 "1: movli.l @%2, %0 ! atomic_" #op "\n" \
26 " " #op " %1, %0 \n" \
27 " movco.l %0, @%2 \n" \
28 " bf 1b \n" \
29 : "=&z" (tmp) \
30 : "r" (i), "r" (&v->counter) \
31 : "t"); \
32 }
33
34 #define ATOMIC_OP_RETURN(op) \
35 static inline int atomic_##op##_return(int i, atomic_t *v) \
36 { \
37 unsigned long temp; \
38 \
39 __asm__ __volatile__ ( \
40 "1: movli.l @%2, %0 ! atomic_" #op "_return \n" \
41 " " #op " %1, %0 \n" \
42 " movco.l %0, @%2 \n" \
43 " bf 1b \n" \
44 " synco \n" \
45 : "=&z" (temp) \
46 : "r" (i), "r" (&v->counter) \
47 : "t"); \
48 \
49 return temp; \
50 }
51
52 #define ATOMIC_FETCH_OP(op) \
53 static inline int atomic_fetch_##op(int i, atomic_t *v) \
54 { \
55 unsigned long res, temp; \
56 \
57 __asm__ __volatile__ ( \
58 "1: movli.l @%3, %0 ! atomic_fetch_" #op " \n" \
59 " mov %0, %1 \n" \
60 " " #op " %2, %0 \n" \
61 " movco.l %0, @%3 \n" \
62 " bf 1b \n" \
63 " synco \n" \
64 : "=&z" (temp), "=&r" (res) \
65 : "r" (i), "r" (&v->counter) \
66 : "t"); \
67 \
68 return res; \
69 }
70
71 #define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op)
72
73 ATOMIC_OPS(add)
74 ATOMIC_OPS(sub)
75
76 #undef ATOMIC_OPS
77 #define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op)
78
79 ATOMIC_OPS(and)
80 ATOMIC_OPS(or)
81 ATOMIC_OPS(xor)
82
83 #undef ATOMIC_OPS
84 #undef ATOMIC_FETCH_OP
85 #undef ATOMIC_OP_RETURN
86 #undef ATOMIC_OP
87
88 #endif /* __ASM_SH_ATOMIC_LLSC_H */