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)							\
20static inline void arch_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)						\
35static inline int arch_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)						\
53static inline int arch_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
73ATOMIC_OPS(add)
74ATOMIC_OPS(sub)
75
76#define arch_atomic_add_return	arch_atomic_add_return
77#define arch_atomic_sub_return	arch_atomic_sub_return
78#define arch_atomic_fetch_add	arch_atomic_fetch_add
79#define arch_atomic_fetch_sub	arch_atomic_fetch_sub
80
81#undef ATOMIC_OPS
82#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op)
83
84ATOMIC_OPS(and)
85ATOMIC_OPS(or)
86ATOMIC_OPS(xor)
87
88#define arch_atomic_fetch_and	arch_atomic_fetch_and
89#define arch_atomic_fetch_or	arch_atomic_fetch_or
90#define arch_atomic_fetch_xor	arch_atomic_fetch_xor
91
92#undef ATOMIC_OPS
93#undef ATOMIC_FETCH_OP
94#undef ATOMIC_OP_RETURN
95#undef ATOMIC_OP
96
97#endif /* __ASM_SH_ATOMIC_LLSC_H */
98