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 __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
  44 static inline void sema_init (struct semaphore *sem, int val)
  45 {
  46         *sem = (struct semaphore)__SEMAPHORE_INITIALIZER(*sem, val);
  47 }
  48
  49 static inline void init_MUTEX (struct semaphore *sem)
  50 {
  51         sema_init(sem, 1);
  52 }
  53
  54 static inline void init_MUTEX_LOCKED (struct semaphore *sem)
  55 {
  56         sema_init(sem, 0);
  57 }
  58
  59 asmlinkage void __down_failed(void /* special register calling convention */);
  60 asmlinkage int  __down_failed_interruptible(void  /* params in registers */);
  61 asmlinkage int  __down_failed_trylock(void  /* params in registers */);
  62 asmlinkage void __up_wakeup(void /* special register calling convention */);
  63
  64 asmlinkage void __down(struct semaphore * sem);
  65 asmlinkage int  __down_interruptible(struct semaphore * sem);
  66 asmlinkage int  __down_trylock(struct semaphore * sem);
  67 asmlinkage void __up(struct semaphore * sem);
  68
  69 extern 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  */
  76 static 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
 102 static 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
 130 static 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  */
 166 static 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