[deliverable/linux.git] / include / asm-m68knommu / semaphore.h

#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 __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)

extern 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
 */
extern 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");
}

extern 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);
}

extern 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().
 */
extern 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
Commit	Line	Data
1da177e4 LT	1	#ifndef _M68K_SEMAPHORE_H
	2	#define _M68K_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	* m68k version by Andreas Schwab
	22	*/
	23
	24
	25	struct semaphore {
	26	atomic_t count;
	27	atomic_t waking;
	28	wait_queue_head_t wait;
	29	};
	30
	31	#define __SEMAPHORE_INITIALIZER(name, n) \
	32	{ \
	33	.count = ATOMIC_INIT(n), \
	34	.waking = ATOMIC_INIT(0), \
	35	.wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \
	36	}
	37
	38	#define __MUTEX_INITIALIZER(name) \
	39	__SEMAPHORE_INITIALIZER(name,1)
	40
	41	#define __DECLARE_SEMAPHORE_GENERIC(name,count) \
	42	struct semaphore name = __SEMAPHORE_INITIALIZER(name,count)
	43
	44	#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1)
	45	#define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name,0)
	46
	47	extern inline void sema_init (struct semaphore *sem, int val)
	48	{
	49	sem = (struct semaphore)__SEMAPHORE_INITIALIZER(sem, val);
	50	}
	51
	52	static inline void init_MUTEX (struct semaphore *sem)
	53	{
	54	sema_init(sem, 1);
	55	}
	56
	57	static inline void init_MUTEX_LOCKED (struct semaphore *sem)
	58	{
	59	sema_init(sem, 0);
	60	}
	61
	62	asmlinkage void __down_failed(void /* special register calling convention */);
	63	asmlinkage int __down_failed_interruptible(void /* params in registers */);
	64	asmlinkage int __down_failed_trylock(void /* params in registers */);
65	asmlinkage void __up_wakeup(void /* special register calling convention */);
66
67	asmlinkage void __down(struct semaphore * sem);
68	asmlinkage int __down_interruptible(struct semaphore * sem);
69	asmlinkage int __down_trylock(struct semaphore * sem);
70	asmlinkage void __up(struct semaphore * sem);
71
72	extern spinlock_t semaphore_wake_lock;
73
74	/*
75	* This is ugly, but we want the default case to fall through.
76	* "down_failed" is a special asm handler that calls the C
77	* routine that actually waits. See arch/m68k/lib/semaphore.S
78	*/
79	extern inline void down(struct semaphore * sem)
80	{
81	might_sleep();
82	__asm__ __volatile__(
83	"\| atomic down operation\n\t"
84	"movel %0, %%a1\n\t"
85	"lea %%pc@(1f), %%a0\n\t"
86	"subql #1, %%a1@\n\t"
87	"jmi __down_failed\n"
88	"1:"
89	: /* no outputs */
90	: "g" (sem)
91	: "cc", "%a0", "%a1", "memory");
92	}
93
94	extern inline int down_interruptible(struct semaphore * sem)
95	{
96	int ret;
97
98	might_sleep();
99	__asm__ __volatile__(
100	"\| atomic down operation\n\t"
101	"movel %1, %%a1\n\t"
102	"lea %%pc@(1f), %%a0\n\t"
103	"subql #1, %%a1@\n\t"
104	"jmi __down_failed_interruptible\n\t"
105	"clrl %%d0\n"
106	"1: movel %%d0, %0\n"
107	: "=d" (ret)
108	: "g" (sem)
109	: "cc", "%d0", "%a0", "%a1", "memory");
110	return(ret);
111	}
112
113	extern inline int down_trylock(struct semaphore * sem)
114	{
115	register struct semaphore *sem1 __asm__ ("%a1") = sem;
116	register int result __asm__ ("%d0");
117
118	__asm__ __volatile__(
119	"\| atomic down trylock operation\n\t"
120	"subql #1,%1@\n\t"
121	"jmi 2f\n\t"
122	"clrl %0\n"
123	"1:\n"
124	".section .text.lock,\"ax\"\n"
125	".even\n"
126	"2:\tpea 1b\n\t"
127	"jbra __down_failed_trylock\n"
128	".previous"
129	: "=d" (result)
130	: "a" (sem1)
131	: "memory");
132	return result;
133	}
134
135	/*
136	* Note! This is subtle. We jump to wake people up only if
137	* the semaphore was negative (== somebody was waiting on it).
138	* The default case (no contention) will result in NO
139	* jumps for both down() and up().
140	*/
141	extern inline void up(struct semaphore * sem)
142	{
143	__asm__ __volatile__(
144	"\| atomic up operation\n\t"
145	"movel %0, %%a1\n\t"
146	"lea %%pc@(1f), %%a0\n\t"
147	"addql #1, %%a1@\n\t"
148	"jle __up_wakeup\n"
149	"1:"
150	: /* no outputs */
151	: "g" (sem)
152	: "cc", "%a0", "%a1", "memory");
153	}
154
155	#endif /* __ASSEMBLY__ */
156
157	#endif