git.oblomov.eu Git - linux-2.6/blob - include/asm-h8300/semaphore.h

   1 #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
  25 struct 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
  38 #define __MUTEX_INITIALIZER(name) \
  39         __SEMAPHORE_INITIALIZER(name,1)
  40
  41 #define __DECLARE_SEMAPHORE_GENERIC(name,count) \
  42         struct semaphore name = __SEMAPHORE_INITIALIZER(name,count)
  43
  44 #define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1)
  45 #define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name,0)
  46
  47 static inline void sema_init (struct semaphore *sem, int val)
  48 {
  49         *sem = (struct semaphore)__SEMAPHORE_INITIALIZER(*sem, val);
  50 }
  51
  52 static inline void init_MUTEX (struct semaphore *sem)
  53 {
  54         sema_init(sem, 1);
  55 }
  56
  57 static inline void init_MUTEX_LOCKED (struct semaphore *sem)
  58 {
  59         sema_init(sem, 0);
  60 }
  61
  62 asmlinkage void __down_failed(void /* special register calling convention */);
  63 asmlinkage int  __down_failed_interruptible(void  /* params in registers */);
  64 asmlinkage int  __down_failed_trylock(void  /* params in registers */);
  65 asmlinkage void __up_wakeup(void /* special register calling convention */);
  66
  67 asmlinkage void __down(struct semaphore * sem);
  68 asmlinkage int  __down_interruptible(struct semaphore * sem);
  69 asmlinkage int  __down_trylock(struct semaphore * sem);
  70 asmlinkage void __up(struct semaphore * sem);
  71
  72 extern spinlock_t semaphore_wake_lock;
  73
  74 /*
  75  * This is ugly, but we want the default case to fall through.
  76  * "down_failed" is a special asm handler that calls the C
  77  * routine that actually waits. See arch/m68k/lib/semaphore.S
  78  */
  79 static inline void down(struct semaphore * sem)
  80 {
  81         register atomic_t *count asm("er0");
  82
  83         might_sleep();
  84
  85         count = &(sem->count);
  86         __asm__ __volatile__(
  87                 "stc ccr,r3l\n\t"
  88                 "orc #0x80,ccr\n\t"
  89                 "mov.l %2, er1\n\t"
  90                 "dec.l #1,er1\n\t"
  91                 "mov.l er1,%0\n\t"
  92                 "bpl 1f\n\t"
  93                 "ldc r3l,ccr\n\t"
  94                 "mov.l %1,er0\n\t"
  95                 "jsr @___down\n\t"
  96                 "bra 2f\n"
  97                 "1:\n\t"
  98                 "ldc r3l,ccr\n"
  99                 "2:"
 100                 : "=m"(*count)
 101                 : "g"(sem),"m"(*count)
 102                 : "cc",  "er1", "er2", "er3");
 103 }
 104
 105 static inline int down_interruptible(struct semaphore * sem)
 106 {
 107         register atomic_t *count asm("er0");
 108
 109         might_sleep();
 110
 111         count = &(sem->count);
 112         __asm__ __volatile__(
 113                 "stc ccr,r1l\n\t"
 114                 "orc #0x80,ccr\n\t"
 115                 "mov.l %3, er2\n\t"
 116                 "dec.l #1,er2\n\t"
 117                 "mov.l er2,%1\n\t"
 118                 "bpl 1f\n\t"
 119                 "ldc r1l,ccr\n\t"
 120                 "mov.l %2,er0\n\t"
 121                 "jsr @___down_interruptible\n\t"
 122                 "bra 2f\n"
 123                 "1:\n\t"
 124                 "ldc r1l,ccr\n\t"
 125                 "sub.l %0,%0\n\t"
 126                 "2:\n\t"
 127                 : "=r" (count),"=m" (*count)
 128                 : "g"(sem),"m"(*count)
 129                 : "cc", "er1", "er2", "er3");
 130         return (int)count;
 131 }
 132
 133 static inline int down_trylock(struct semaphore * sem)
 134 {
 135         register atomic_t *count asm("er0");
 136
 137         count = &(sem->count);
 138         __asm__ __volatile__(
 139                 "stc ccr,r3l\n\t"
 140                 "orc #0x80,ccr\n\t"
 141                 "mov.l %3,er2\n\t"
 142                 "dec.l #1,er2\n\t"
 143                 "mov.l er2,%0\n\t"
 144                 "bpl 1f\n\t"
 145                 "ldc r3l,ccr\n\t"
 146                 "jmp @3f\n\t"
 147                 LOCK_SECTION_START(".align 2\n\t")
 148                 "3:\n\t"
 149                 "mov.l %2,er0\n\t"
 150                 "jsr @___down_trylock\n\t"
 151                 "jmp @2f\n\t"
 152                 LOCK_SECTION_END
 153                 "1:\n\t"
 154                 "ldc r3l,ccr\n\t"
 155                 "sub.l %1,%1\n"
 156                 "2:"
 157                 : "=m" (*count),"=r"(count)
 158                 : "g"(sem),"m"(*count)
 159                 : "cc", "er1","er2", "er3");
 160         return (int)count;
 161 }
 162
 163 /*
 164  * Note! This is subtle. We jump to wake people up only if
 165  * the semaphore was negative (== somebody was waiting on it).
 166  * The default case (no contention) will result in NO
 167  * jumps for both down() and up().
 168  */
 169 static inline void up(struct semaphore * sem)
 170 {
 171         register atomic_t *count asm("er0");
 172
 173         count = &(sem->count);
 174         __asm__ __volatile__(
 175                 "stc ccr,r3l\n\t"
 176                 "orc #0x80,ccr\n\t"
 177                 "mov.l %2,er1\n\t"
 178                 "inc.l #1,er1\n\t"
 179                 "mov.l er1,%0\n\t"
 180                 "ldc r3l,ccr\n\t"
 181                 "sub.l er2,er2\n\t"
 182                 "cmp.l er2,er1\n\t"
 183                 "bgt 1f\n\t"
 184                 "mov.l %1,er0\n\t"
 185                 "jsr @___up\n"
 186                 "1:"
 187                 : "=m"(*count)
 188                 : "g"(sem),"m"(*count)
 189                 : "cc", "er1", "er2", "er3");
 190 }
 191
 192 #endif /* __ASSEMBLY__ */
 193
 194 #endif