154 lines
3.5 KiB
C
154 lines
3.5 KiB
C
#ifndef _M68K_SEMAPHORE_H
|
|
#define _M68K_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
|
|
*
|
|
* m68k version by Andreas Schwab
|
|
*/
|
|
|
|
|
|
struct semaphore {
|
|
atomic_t count;
|
|
atomic_t waking;
|
|
wait_queue_head_t wait;
|
|
};
|
|
|
|
#define __SEMAPHORE_INITIALIZER(name, n) \
|
|
{ \
|
|
.count = ATOMIC_INIT(n), \
|
|
.waking = ATOMIC_INIT(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)
|
|
{
|
|
might_sleep();
|
|
__asm__ __volatile__(
|
|
"| atomic down operation\n\t"
|
|
"movel %0, %%a1\n\t"
|
|
"lea %%pc@(1f), %%a0\n\t"
|
|
"subql #1, %%a1@\n\t"
|
|
"jmi __down_failed\n"
|
|
"1:"
|
|
: /* no outputs */
|
|
: "g" (sem)
|
|
: "cc", "%a0", "%a1", "memory");
|
|
}
|
|
|
|
static inline int down_interruptible(struct semaphore * sem)
|
|
{
|
|
int ret;
|
|
|
|
might_sleep();
|
|
__asm__ __volatile__(
|
|
"| atomic down operation\n\t"
|
|
"movel %1, %%a1\n\t"
|
|
"lea %%pc@(1f), %%a0\n\t"
|
|
"subql #1, %%a1@\n\t"
|
|
"jmi __down_failed_interruptible\n\t"
|
|
"clrl %%d0\n"
|
|
"1: movel %%d0, %0\n"
|
|
: "=d" (ret)
|
|
: "g" (sem)
|
|
: "cc", "%d0", "%a0", "%a1", "memory");
|
|
return(ret);
|
|
}
|
|
|
|
static inline int down_trylock(struct semaphore * sem)
|
|
{
|
|
register struct semaphore *sem1 __asm__ ("%a1") = sem;
|
|
register int result __asm__ ("%d0");
|
|
|
|
__asm__ __volatile__(
|
|
"| atomic down trylock operation\n\t"
|
|
"subql #1,%1@\n\t"
|
|
"jmi 2f\n\t"
|
|
"clrl %0\n"
|
|
"1:\n"
|
|
".section .text.lock,\"ax\"\n"
|
|
".even\n"
|
|
"2:\tpea 1b\n\t"
|
|
"jbra __down_failed_trylock\n"
|
|
".previous"
|
|
: "=d" (result)
|
|
: "a" (sem1)
|
|
: "memory");
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
__asm__ __volatile__(
|
|
"| atomic up operation\n\t"
|
|
"movel %0, %%a1\n\t"
|
|
"lea %%pc@(1f), %%a0\n\t"
|
|
"addql #1, %%a1@\n\t"
|
|
"jle __up_wakeup\n"
|
|
"1:"
|
|
: /* no outputs */
|
|
: "g" (sem)
|
|
: "cc", "%a0", "%a1", "memory");
|
|
}
|
|
|
|
#endif /* __ASSEMBLY__ */
|
|
|
|
#endif
|