| #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) |
| #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 |