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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef _H8300_SEMAPHORE_H
2#define _H8300_SEMAPHORE_H
3
4#define RW_LOCK_BIAS 0x01000000
5
6#ifndef __ASSEMBLY__
7
8#include <linux/linkage.h>
9#include <linux/wait.h>
10#include <linux/spinlock.h>
11#include <linux/rwsem.h>
12
13#include <asm/system.h>
14#include <asm/atomic.h>
15
16/*
17 * Interrupt-safe semaphores..
18 *
19 * (C) Copyright 1996 Linus Torvalds
20 *
21 * H8/300 version by Yoshinori Sato
22 */
23
24
25struct semaphore {
26 atomic_t count;
27 int sleepers;
28 wait_queue_head_t wait;
29};
30
31#define __SEMAPHORE_INITIALIZER(name, n) \
32{ \
33 .count = ATOMIC_INIT(n), \
34 .sleepers = 0, \
35 .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \
36}
37
Linus Torvalds1da177e2005-04-16 15:20:36 -070038#define __DECLARE_SEMAPHORE_GENERIC(name,count) \
39 struct semaphore name = __SEMAPHORE_INITIALIZER(name,count)
40
41#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1)
42#define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name,0)
43
44static inline void sema_init (struct semaphore *sem, int val)
45{
46 *sem = (struct semaphore)__SEMAPHORE_INITIALIZER(*sem, val);
47}
48
49static inline void init_MUTEX (struct semaphore *sem)
50{
51 sema_init(sem, 1);
52}
53
54static inline void init_MUTEX_LOCKED (struct semaphore *sem)
55{
56 sema_init(sem, 0);
57}
58
59asmlinkage void __down_failed(void /* special register calling convention */);
60asmlinkage int __down_failed_interruptible(void /* params in registers */);
61asmlinkage int __down_failed_trylock(void /* params in registers */);
62asmlinkage void __up_wakeup(void /* special register calling convention */);
63
64asmlinkage void __down(struct semaphore * sem);
65asmlinkage int __down_interruptible(struct semaphore * sem);
66asmlinkage int __down_trylock(struct semaphore * sem);
67asmlinkage void __up(struct semaphore * sem);
68
69extern spinlock_t semaphore_wake_lock;
70
71/*
72 * This is ugly, but we want the default case to fall through.
73 * "down_failed" is a special asm handler that calls the C
74 * routine that actually waits. See arch/m68k/lib/semaphore.S
75 */
76static inline void down(struct semaphore * sem)
77{
78 register atomic_t *count asm("er0");
79
80 might_sleep();
81
82 count = &(sem->count);
83 __asm__ __volatile__(
84 "stc ccr,r3l\n\t"
85 "orc #0x80,ccr\n\t"
86 "mov.l %2, er1\n\t"
87 "dec.l #1,er1\n\t"
88 "mov.l er1,%0\n\t"
89 "bpl 1f\n\t"
90 "ldc r3l,ccr\n\t"
91 "mov.l %1,er0\n\t"
92 "jsr @___down\n\t"
93 "bra 2f\n"
94 "1:\n\t"
95 "ldc r3l,ccr\n"
96 "2:"
97 : "=m"(*count)
98 : "g"(sem),"m"(*count)
99 : "cc", "er1", "er2", "er3");
100}
101
102static inline int down_interruptible(struct semaphore * sem)
103{
104 register atomic_t *count asm("er0");
105
106 might_sleep();
107
108 count = &(sem->count);
109 __asm__ __volatile__(
110 "stc ccr,r1l\n\t"
111 "orc #0x80,ccr\n\t"
112 "mov.l %3, er2\n\t"
113 "dec.l #1,er2\n\t"
114 "mov.l er2,%1\n\t"
115 "bpl 1f\n\t"
116 "ldc r1l,ccr\n\t"
117 "mov.l %2,er0\n\t"
118 "jsr @___down_interruptible\n\t"
119 "bra 2f\n"
120 "1:\n\t"
121 "ldc r1l,ccr\n\t"
122 "sub.l %0,%0\n\t"
123 "2:\n\t"
124 : "=r" (count),"=m" (*count)
125 : "g"(sem),"m"(*count)
126 : "cc", "er1", "er2", "er3");
127 return (int)count;
128}
129
130static inline int down_trylock(struct semaphore * sem)
131{
132 register atomic_t *count asm("er0");
133
134 count = &(sem->count);
135 __asm__ __volatile__(
136 "stc ccr,r3l\n\t"
137 "orc #0x80,ccr\n\t"
138 "mov.l %3,er2\n\t"
139 "dec.l #1,er2\n\t"
140 "mov.l er2,%0\n\t"
141 "bpl 1f\n\t"
142 "ldc r3l,ccr\n\t"
143 "jmp @3f\n\t"
144 LOCK_SECTION_START(".align 2\n\t")
145 "3:\n\t"
146 "mov.l %2,er0\n\t"
147 "jsr @___down_trylock\n\t"
148 "jmp @2f\n\t"
149 LOCK_SECTION_END
150 "1:\n\t"
151 "ldc r3l,ccr\n\t"
152 "sub.l %1,%1\n"
153 "2:"
154 : "=m" (*count),"=r"(count)
155 : "g"(sem),"m"(*count)
156 : "cc", "er1","er2", "er3");
157 return (int)count;
158}
159
160/*
161 * Note! This is subtle. We jump to wake people up only if
162 * the semaphore was negative (== somebody was waiting on it).
163 * The default case (no contention) will result in NO
164 * jumps for both down() and up().
165 */
166static inline void up(struct semaphore * sem)
167{
168 register atomic_t *count asm("er0");
169
170 count = &(sem->count);
171 __asm__ __volatile__(
172 "stc ccr,r3l\n\t"
173 "orc #0x80,ccr\n\t"
174 "mov.l %2,er1\n\t"
175 "inc.l #1,er1\n\t"
176 "mov.l er1,%0\n\t"
177 "ldc r3l,ccr\n\t"
178 "sub.l er2,er2\n\t"
179 "cmp.l er2,er1\n\t"
180 "bgt 1f\n\t"
181 "mov.l %1,er0\n\t"
182 "jsr @___up\n"
183 "1:"
184 : "=m"(*count)
185 : "g"(sem),"m"(*count)
186 : "cc", "er1", "er2", "er3");
187}
188
189#endif /* __ASSEMBLY__ */
190
191#endif