1 #ifndef __ASM_SH_ATOMIC_LLSC_H
2 #define __ASM_SH_ATOMIC_LLSC_H
3
4 /*
5 * SH-4A note:
6 *
7 * We basically get atomic_xxx_return() for free compared with
8 * atomic_xxx(). movli.l/movco.l require r0 due to the instruction
9 * encoding, so the retval is automatically set without having to
10 * do any special work.
11 */
12 /*
13 * To get proper branch prediction for the main line, we must branch
14 * forward to code at the end of this object's .text section, then
15 * branch back to restart the operation.
16 */
17
18 #define ATOMIC_OP(op) \
19 static inline void atomic_##op(int i, atomic_t *v) \
20 { \
21 unsigned long tmp; \
22 \
23 __asm__ __volatile__ ( \
24 "1: movli.l @%2, %0 ! atomic_" #op "\n" \
25 " " #op " %1, %0 \n" \
26 " movco.l %0, @%2 \n" \
27 " bf 1b \n" \
28 : "=&z" (tmp) \
29 : "r" (i), "r" (&v->counter) \
30 : "t"); \
31 }
32
33 #define ATOMIC_OP_RETURN(op) \
34 static inline int atomic_##op##_return(int i, atomic_t *v) \
35 { \
36 unsigned long temp; \
37 \
38 __asm__ __volatile__ ( \
39 "1: movli.l @%2, %0 ! atomic_" #op "_return \n" \
40 " " #op " %1, %0 \n" \
41 " movco.l %0, @%2 \n" \
42 " bf 1b \n" \
43 " synco \n" \
44 : "=&z" (temp) \
45 : "r" (i), "r" (&v->counter) \
46 : "t"); \
47 \
48 return temp; \
49 }
50
51 #define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
52
53 ATOMIC_OPS(add)
ATOMIC_OPS(sub)54 ATOMIC_OPS(sub)
55
56 #undef ATOMIC_OPS
57 #undef ATOMIC_OP_RETURN
58 #undef ATOMIC_OP
59
60 static inline void atomic_clear_mask(unsigned int mask, atomic_t *v)
61 {
62 unsigned long tmp;
63
64 __asm__ __volatile__ (
65 "1: movli.l @%2, %0 ! atomic_clear_mask \n"
66 " and %1, %0 \n"
67 " movco.l %0, @%2 \n"
68 " bf 1b \n"
69 : "=&z" (tmp)
70 : "r" (~mask), "r" (&v->counter)
71 : "t");
72 }
73
atomic_set_mask(unsigned int mask,atomic_t * v)74 static inline void atomic_set_mask(unsigned int mask, atomic_t *v)
75 {
76 unsigned long tmp;
77
78 __asm__ __volatile__ (
79 "1: movli.l @%2, %0 ! atomic_set_mask \n"
80 " or %1, %0 \n"
81 " movco.l %0, @%2 \n"
82 " bf 1b \n"
83 : "=&z" (tmp)
84 : "r" (mask), "r" (&v->counter)
85 : "t");
86 }
87
88 #endif /* __ASM_SH_ATOMIC_LLSC_H */
89