1*b551173bSSimon Glass #ifndef _ASM_X86_ATOMIC_H
2*b551173bSSimon Glass #define _ASM_X86_ATOMIC_H
3*b551173bSSimon Glass
4*b551173bSSimon Glass #include <linux/compiler.h>
5*b551173bSSimon Glass #include <linux/types.h>
6*b551173bSSimon Glass #include <asm/processor.h>
7*b551173bSSimon Glass
8*b551173bSSimon Glass typedef struct { volatile int counter; } atomic_t;
9*b551173bSSimon Glass
10*b551173bSSimon Glass /*
11*b551173bSSimon Glass * Atomic operations that C can't guarantee us. Useful for
12*b551173bSSimon Glass * resource counting etc..
13*b551173bSSimon Glass */
14*b551173bSSimon Glass
15*b551173bSSimon Glass #define ATOMIC_INIT(i) { (i) }
16*b551173bSSimon Glass
17*b551173bSSimon Glass /**
18*b551173bSSimon Glass * atomic_read - read atomic variable
19*b551173bSSimon Glass * @v: pointer of type atomic_t
20*b551173bSSimon Glass *
21*b551173bSSimon Glass * Atomically reads the value of @v.
22*b551173bSSimon Glass */
atomic_read(const atomic_t * v)23*b551173bSSimon Glass static inline int atomic_read(const atomic_t *v)
24*b551173bSSimon Glass {
25*b551173bSSimon Glass return ACCESS_ONCE((v)->counter);
26*b551173bSSimon Glass }
27*b551173bSSimon Glass
28*b551173bSSimon Glass /**
29*b551173bSSimon Glass * atomic_set - set atomic variable
30*b551173bSSimon Glass * @v: pointer of type atomic_t
31*b551173bSSimon Glass * @i: required value
32*b551173bSSimon Glass *
33*b551173bSSimon Glass * Atomically sets the value of @v to @i.
34*b551173bSSimon Glass */
atomic_set(atomic_t * v,int i)35*b551173bSSimon Glass static inline void atomic_set(atomic_t *v, int i)
36*b551173bSSimon Glass {
37*b551173bSSimon Glass v->counter = i;
38*b551173bSSimon Glass }
39*b551173bSSimon Glass
40*b551173bSSimon Glass /**
41*b551173bSSimon Glass * atomic_add - add integer to atomic variable
42*b551173bSSimon Glass * @i: integer value to add
43*b551173bSSimon Glass * @v: pointer of type atomic_t
44*b551173bSSimon Glass *
45*b551173bSSimon Glass * Atomically adds @i to @v.
46*b551173bSSimon Glass */
atomic_add(int i,atomic_t * v)47*b551173bSSimon Glass static inline void atomic_add(int i, atomic_t *v)
48*b551173bSSimon Glass {
49*b551173bSSimon Glass asm volatile(LOCK_PREFIX "addl %1,%0"
50*b551173bSSimon Glass : "+m" (v->counter)
51*b551173bSSimon Glass : "ir" (i));
52*b551173bSSimon Glass }
53*b551173bSSimon Glass
54*b551173bSSimon Glass /**
55*b551173bSSimon Glass * atomic_sub - subtract integer from atomic variable
56*b551173bSSimon Glass * @i: integer value to subtract
57*b551173bSSimon Glass * @v: pointer of type atomic_t
58*b551173bSSimon Glass *
59*b551173bSSimon Glass * Atomically subtracts @i from @v.
60*b551173bSSimon Glass */
atomic_sub(int i,atomic_t * v)61*b551173bSSimon Glass static inline void atomic_sub(int i, atomic_t *v)
62*b551173bSSimon Glass {
63*b551173bSSimon Glass asm volatile(LOCK_PREFIX "subl %1,%0"
64*b551173bSSimon Glass : "+m" (v->counter)
65*b551173bSSimon Glass : "ir" (i));
66*b551173bSSimon Glass }
67*b551173bSSimon Glass
68*b551173bSSimon Glass /**
69*b551173bSSimon Glass * atomic_inc - increment atomic variable
70*b551173bSSimon Glass * @v: pointer of type atomic_t
71*b551173bSSimon Glass *
72*b551173bSSimon Glass * Atomically increments @v by 1.
73*b551173bSSimon Glass */
atomic_inc(atomic_t * v)74*b551173bSSimon Glass static inline void atomic_inc(atomic_t *v)
75*b551173bSSimon Glass {
76*b551173bSSimon Glass asm volatile(LOCK_PREFIX "incl %0"
77*b551173bSSimon Glass : "+m" (v->counter));
78*b551173bSSimon Glass }
79*b551173bSSimon Glass
80*b551173bSSimon Glass /**
81*b551173bSSimon Glass * atomic_dec - decrement atomic variable
82*b551173bSSimon Glass * @v: pointer of type atomic_t
83*b551173bSSimon Glass *
84*b551173bSSimon Glass * Atomically decrements @v by 1.
85*b551173bSSimon Glass */
atomic_dec(atomic_t * v)86*b551173bSSimon Glass static inline void atomic_dec(atomic_t *v)
87*b551173bSSimon Glass {
88*b551173bSSimon Glass asm volatile(LOCK_PREFIX "decl %0"
89*b551173bSSimon Glass : "+m" (v->counter));
90*b551173bSSimon Glass }
91*b551173bSSimon Glass
92*b551173bSSimon Glass /**
93*b551173bSSimon Glass * atomic_inc_short - increment of a short integer
94*b551173bSSimon Glass * @v: pointer to type int
95*b551173bSSimon Glass *
96*b551173bSSimon Glass * Atomically adds 1 to @v
97*b551173bSSimon Glass * Returns the new value of @u
98*b551173bSSimon Glass */
atomic_inc_short(short int * v)99*b551173bSSimon Glass static inline short int atomic_inc_short(short int *v)
100*b551173bSSimon Glass {
101*b551173bSSimon Glass asm(LOCK_PREFIX "addw $1, %0" : "+m" (*v));
102*b551173bSSimon Glass return *v;
103*b551173bSSimon Glass }
104*b551173bSSimon Glass
105*b551173bSSimon Glass /* These are x86-specific, used by some header files */
106*b551173bSSimon Glass #define atomic_clear_mask(mask, addr) \
107*b551173bSSimon Glass asm volatile(LOCK_PREFIX "andl %0,%1" \
108*b551173bSSimon Glass : : "r" (~(mask)), "m" (*(addr)) : "memory")
109*b551173bSSimon Glass
110*b551173bSSimon Glass #define atomic_set_mask(mask, addr) \
111*b551173bSSimon Glass asm volatile(LOCK_PREFIX "orl %0,%1" \
112*b551173bSSimon Glass : : "r" ((unsigned)(mask)), "m" (*(addr)) \
113*b551173bSSimon Glass : "memory")
114*b551173bSSimon Glass
115*b551173bSSimon Glass #endif /* _ASM_X86_ATOMIC_H */
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