include/asm-sparc/semaphore.h

   1 #ifndef _SPARC_SEMAPHORE_H
   2 #define _SPARC_SEMAPHORE_H
   3
   4 /* Dinky, good for nothing, just barely irq safe, Sparc semaphores. */
   5
   6 #ifdef __KERNEL__
   7
   8 #include <asm/atomic.h>
   9 #include <linux/wait.h>
  10 #include <linux/rwsem.h>
  11
  12 struct semaphore {
  13         atomic24_t count;
  14         int sleepers;
  15         wait_queue_head_t wait;
  16 };
  17
  18 #define __SEMAPHORE_INITIALIZER(name, n)                                \
  19 {                                                                       \
  20         .count          = ATOMIC24_INIT(n),                             \
  21         .sleepers       = 0,                                            \
  22         .wait           = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait)    \
  23 }
  24
  25 #define __DECLARE_SEMAPHORE_GENERIC(name,count) \
  26         struct semaphore name = __SEMAPHORE_INITIALIZER(name,count)
  27
  28 #define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1)
  29 #define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name,0)
  30
  31 static inline void sema_init (struct semaphore *sem, int val)
  32 {
  33         atomic24_set(&sem->count, val);
  34         sem->sleepers = 0;
  35         init_waitqueue_head(&sem->wait);
  36 }
  37
  38 static inline void init_MUTEX (struct semaphore *sem)
  39 {
  40         sema_init(sem, 1);
  41 }
  42
  43 static inline void init_MUTEX_LOCKED (struct semaphore *sem)
  44 {
  45         sema_init(sem, 0);
  46 }
  47
  48 extern void __down(struct semaphore * sem);
  49 extern int __down_interruptible(struct semaphore * sem);
  50 extern int __down_trylock(struct semaphore * sem);
  51 extern void __up(struct semaphore * sem);
  52
  53 static inline void down(struct semaphore * sem)
  54 {
  55         register volatile int *ptr asm("g1");
  56         register int increment asm("g2");
  57
  58         might_sleep();
  59
  60         ptr = &(sem->count.counter);
  61         increment = 1;
  62
  63         __asm__ __volatile__(
  64         "mov    %%o7, %%g4\n\t"
  65         "call   ___atomic24_sub\n\t"
  66         " add   %%o7, 8, %%o7\n\t"
  67         "tst    %%g2\n\t"
  68         "bl     2f\n\t"
  69         " nop\n"
  70         "1:\n\t"
  71         ".subsection 2\n"
  72         "2:\n\t"
  73         "save   %%sp, -64, %%sp\n\t"
  74         "mov    %%g1, %%l1\n\t"
  75         "mov    %%g5, %%l5\n\t"
  76         "call   %3\n\t"
  77         " mov   %%g1, %%o0\n\t"
  78         "mov    %%l1, %%g1\n\t"
  79         "ba     1b\n\t"
  80         " restore %%l5, %%g0, %%g5\n\t"
  81         ".previous\n"
  82         : "=&r" (increment)
  83         : "0" (increment), "r" (ptr), "i" (__down)
  84         : "g3", "g4", "g7", "memory", "cc");
  85 }
  86
  87 static inline int down_interruptible(struct semaphore * sem)
  88 {
  89         register volatile int *ptr asm("g1");
  90         register int increment asm("g2");
  91
  92         might_sleep();
  93
  94         ptr = &(sem->count.counter);
  95         increment = 1;
  96
  97         __asm__ __volatile__(
  98         "mov    %%o7, %%g4\n\t"
  99         "call   ___atomic24_sub\n\t"
 100         " add   %%o7, 8, %%o7\n\t"
 101         "tst    %%g2\n\t"
 102         "bl     2f\n\t"
 103         " clr   %%g2\n"
 104         "1:\n\t"
 105         ".subsection 2\n"
 106         "2:\n\t"
 107         "save   %%sp, -64, %%sp\n\t"
 108         "mov    %%g1, %%l1\n\t"
 109         "mov    %%g5, %%l5\n\t"
 110         "call   %3\n\t"
 111         " mov   %%g1, %%o0\n\t"
 112         "mov    %%l1, %%g1\n\t"
 113         "mov    %%l5, %%g5\n\t"
 114         "ba     1b\n\t"
 115         " restore %%o0, %%g0, %%g2\n\t"
 116         ".previous\n"
 117         : "=&r" (increment)
 118         : "0" (increment), "r" (ptr), "i" (__down_interruptible)
 119         : "g3", "g4", "g7", "memory", "cc");
 120
 121         return increment;
 122 }
 123
 124 static inline int down_trylock(struct semaphore * sem)
 125 {
 126         register volatile int *ptr asm("g1");
 127         register int increment asm("g2");
 128
 129         ptr = &(sem->count.counter);
 130         increment = 1;
 131
 132         __asm__ __volatile__(
 133         "mov    %%o7, %%g4\n\t"
 134         "call   ___atomic24_sub\n\t"
 135         " add   %%o7, 8, %%o7\n\t"
 136         "tst    %%g2\n\t"
 137         "bl     2f\n\t"
 138         " clr   %%g2\n"
 139         "1:\n\t"
 140         ".subsection 2\n"
 141         "2:\n\t"
 142         "save   %%sp, -64, %%sp\n\t"
 143         "mov    %%g1, %%l1\n\t"
 144         "mov    %%g5, %%l5\n\t"
 145         "call   %3\n\t"
 146         " mov   %%g1, %%o0\n\t"
 147         "mov    %%l1, %%g1\n\t"
 148         "mov    %%l5, %%g5\n\t"
 149         "ba     1b\n\t"
 150         " restore %%o0, %%g0, %%g2\n\t"
 151         ".previous\n"
 152         : "=&r" (increment)
 153         : "0" (increment), "r" (ptr), "i" (__down_trylock)
 154         : "g3", "g4", "g7", "memory", "cc");
 155
 156         return increment;
 157 }
 158
 159 static inline void up(struct semaphore * sem)
 160 {
 161         register volatile int *ptr asm("g1");
 162         register int increment asm("g2");
 163
 164         ptr = &(sem->count.counter);
 165         increment = 1;
 166
 167         __asm__ __volatile__(
 168         "mov    %%o7, %%g4\n\t"
 169         "call   ___atomic24_add\n\t"
 170         " add   %%o7, 8, %%o7\n\t"
 171         "tst    %%g2\n\t"
 172         "ble    2f\n\t"
 173         " nop\n"
 174         "1:\n\t"
 175         ".subsection 2\n"
 176         "2:\n\t"
 177         "save   %%sp, -64, %%sp\n\t"
 178         "mov    %%g1, %%l1\n\t"
 179         "mov    %%g5, %%l5\n\t"
 180         "call   %3\n\t"
 181         " mov   %%g1, %%o0\n\t"
 182         "mov    %%l1, %%g1\n\t"
 183         "ba     1b\n\t"
 184         " restore %%l5, %%g0, %%g5\n\t"
 185         ".previous\n"
 186         : "=&r" (increment)
 187         : "0" (increment), "r" (ptr), "i" (__up)
 188         : "g3", "g4", "g7", "memory", "cc");
 189 }
 190
 191 #endif /* __KERNEL__ */
 192
 193 #endif /* !(_SPARC_SEMAPHORE_H) */