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Diffstat (limited to 'include/asm-h8300/semaphore.h')
| -rw-r--r-- | include/asm-h8300/semaphore.h | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/include/asm-h8300/semaphore.h b/include/asm-h8300/semaphore.h new file mode 100644 index 0000000..fe6ef37 --- /dev/null +++ b/include/asm-h8300/semaphore.h @@ -0,0 +1,194 @@ +#ifndef _H8300_SEMAPHORE_H +#define _H8300_SEMAPHORE_H + +#define RW_LOCK_BIAS 0x01000000 + +#ifndef __ASSEMBLY__ + +#include <linux/linkage.h> +#include <linux/wait.h> +#include <linux/spinlock.h> +#include <linux/rwsem.h> + +#include <asm/system.h> +#include <asm/atomic.h> + +/* + * Interrupt-safe semaphores.. + * + * (C) Copyright 1996 Linus Torvalds + * + * H8/300 version by Yoshinori Sato + */ + + +struct semaphore { + atomic_t count; + int sleepers; + wait_queue_head_t wait; +}; + +#define __SEMAPHORE_INITIALIZER(name, n) \ +{ \ + .count = ATOMIC_INIT(n), \ + .sleepers = 0, \ + .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ +} + +#define __MUTEX_INITIALIZER(name) \ + __SEMAPHORE_INITIALIZER(name,1) + +#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ + struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) + +#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) +#define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name,0) + +static inline void sema_init (struct semaphore *sem, int val) +{ + *sem = (struct semaphore)__SEMAPHORE_INITIALIZER(*sem, val); +} + +static inline void init_MUTEX (struct semaphore *sem) +{ + sema_init(sem, 1); +} + +static inline void init_MUTEX_LOCKED (struct semaphore *sem) +{ + sema_init(sem, 0); +} + +asmlinkage void __down_failed(void /* special register calling convention */); +asmlinkage int __down_failed_interruptible(void /* params in registers */); +asmlinkage int __down_failed_trylock(void /* params in registers */); +asmlinkage void __up_wakeup(void /* special register calling convention */); + +asmlinkage void __down(struct semaphore * sem); +asmlinkage int __down_interruptible(struct semaphore * sem); +asmlinkage int __down_trylock(struct semaphore * sem); +asmlinkage void __up(struct semaphore * sem); + +extern spinlock_t semaphore_wake_lock; + +/* + * This is ugly, but we want the default case to fall through. + * "down_failed" is a special asm handler that calls the C + * routine that actually waits. See arch/m68k/lib/semaphore.S + */ +static inline void down(struct semaphore * sem) +{ + register atomic_t *count asm("er0"); + + might_sleep(); + + count = &(sem->count); + __asm__ __volatile__( + "stc ccr,r3l\n\t" + "orc #0x80,ccr\n\t" + "mov.l %2, er1\n\t" + "dec.l #1,er1\n\t" + "mov.l er1,%0\n\t" + "bpl 1f\n\t" + "ldc r3l,ccr\n\t" + "mov.l %1,er0\n\t" + "jsr @___down\n\t" + "bra 2f\n" + "1:\n\t" + "ldc r3l,ccr\n" + "2:" + : "=m"(*count) + : "g"(sem),"m"(*count) + : "cc", "er1", "er2", "er3"); +} + +static inline int down_interruptible(struct semaphore * sem) +{ + register atomic_t *count asm("er0"); + + might_sleep(); + + count = &(sem->count); + __asm__ __volatile__( + "stc ccr,r1l\n\t" + "orc #0x80,ccr\n\t" + "mov.l %3, er2\n\t" + "dec.l #1,er2\n\t" + "mov.l er2,%1\n\t" + "bpl 1f\n\t" + "ldc r1l,ccr\n\t" + "mov.l %2,er0\n\t" + "jsr @___down_interruptible\n\t" + "bra 2f\n" + "1:\n\t" + "ldc r1l,ccr\n\t" + "sub.l %0,%0\n\t" + "2:\n\t" + : "=r" (count),"=m" (*count) + : "g"(sem),"m"(*count) + : "cc", "er1", "er2", "er3"); + return (int)count; +} + +static inline int down_trylock(struct semaphore * sem) +{ + register atomic_t *count asm("er0"); + + count = &(sem->count); + __asm__ __volatile__( + "stc ccr,r3l\n\t" + "orc #0x80,ccr\n\t" + "mov.l %3,er2\n\t" + "dec.l #1,er2\n\t" + "mov.l er2,%0\n\t" + "bpl 1f\n\t" + "ldc r3l,ccr\n\t" + "jmp @3f\n\t" + LOCK_SECTION_START(".align 2\n\t") + "3:\n\t" + "mov.l %2,er0\n\t" + "jsr @___down_trylock\n\t" + "jmp @2f\n\t" + LOCK_SECTION_END + "1:\n\t" + "ldc r3l,ccr\n\t" + "sub.l %1,%1\n" + "2:" + : "=m" (*count),"=r"(count) + : "g"(sem),"m"(*count) + : "cc", "er1","er2", "er3"); + return (int)count; +} + +/* + * Note! This is subtle. We jump to wake people up only if + * the semaphore was negative (== somebody was waiting on it). + * The default case (no contention) will result in NO + * jumps for both down() and up(). + */ +static inline void up(struct semaphore * sem) +{ + register atomic_t *count asm("er0"); + + count = &(sem->count); + __asm__ __volatile__( + "stc ccr,r3l\n\t" + "orc #0x80,ccr\n\t" + "mov.l %2,er1\n\t" + "inc.l #1,er1\n\t" + "mov.l er1,%0\n\t" + "ldc r3l,ccr\n\t" + "sub.l er2,er2\n\t" + "cmp.l er2,er1\n\t" + "bgt 1f\n\t" + "mov.l %1,er0\n\t" + "jsr @___up\n" + "1:" + : "=m"(*count) + : "g"(sem),"m"(*count) + : "cc", "er1", "er2", "er3"); +} + +#endif /* __ASSEMBLY__ */ + +#endif |
