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#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 __DECLARE_SEMAPHORE_GENERIC(name,count) \
struct semaphore name = __SEMAPHORE_INITIALIZER(name,count)
#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1)
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
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