1 files changed, 161 insertions, 0 deletions
diff --git a/include/asm-frv/semaphore.h b/include/asm-frv/semaphore.h
new file mode 100644
index 000000000000..393545630806
--- /dev/null
+++ b/include/asm-frv/semaphore.h
@@ -0,0 +1,161 @@
+/* semaphore.h: semaphores for the FR-V
+ *
+ * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#ifndef _ASM_SEMAPHORE_H
+#define _ASM_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>
+
+#define SEMAPHORE_DEBUG		WAITQUEUE_DEBUG
+
+/*
+ * the semaphore definition
+ * - if counter is >0 then there are tokens available on the semaphore for down to collect
+ * - if counter is <=0 then there are no spare tokens, and anyone that wants one must wait
+ * - if wait_list is not empty, then there are processes waiting for the semaphore
+ */
+struct semaphore {
+	unsigned		counter;
+	spinlock_t		wait_lock;
+	struct list_head	wait_list;
+#if SEMAPHORE_DEBUG
+	unsigned		__magic;
+#endif
+};
+
+#if SEMAPHORE_DEBUG
+# define __SEM_DEBUG_INIT(name) , (long)&(name).__magic
+#else
+# define __SEM_DEBUG_INIT(name)
+#endif
+
+
+#define __SEMAPHORE_INITIALIZER(name,count) \
+{ count, SPIN_LOCK_UNLOCKED, LIST_HEAD_INIT((name).wait_list) __SEM_DEBUG_INIT(name) }
+
+#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);
+}
+
+extern void __down(struct semaphore *sem, unsigned long flags);
+extern int  __down_interruptible(struct semaphore *sem, unsigned long flags);
+extern void __up(struct semaphore *sem);
+
+static inline void down(struct semaphore *sem)
+{
+	unsigned long flags;
+
+#if SEMAPHORE_DEBUG
+	CHECK_MAGIC(sem->__magic);
+#endif
+
+	spin_lock_irqsave(&sem->wait_lock, flags);
+	if (likely(sem->counter > 0)) {
+		sem->counter--;
+		spin_unlock_irqrestore(&sem->wait_lock, flags);
+	}
+	else {
+		__down(sem, flags);
+	}
+}
+
+static inline int down_interruptible(struct semaphore *sem)
+{
+	unsigned long flags;
+	int ret = 0;
+
+#if SEMAPHORE_DEBUG
+	CHECK_MAGIC(sem->__magic);
+#endif
+
+	spin_lock_irqsave(&sem->wait_lock, flags);
+	if (likely(sem->counter > 0)) {
+		sem->counter--;
+		spin_unlock_irqrestore(&sem->wait_lock, flags);
+	}
+	else {
+		ret = __down_interruptible(sem, flags);
+	}
+	return ret;
+}
+
+/*
+ * non-blockingly attempt to down() a semaphore.
+ * - returns zero if we acquired it
+ */
+static inline int down_trylock(struct semaphore *sem)
+{
+	unsigned long flags;
+	int success = 0;
+
+#if SEMAPHORE_DEBUG
+	CHECK_MAGIC(sem->__magic);
+#endif
+
+	spin_lock_irqsave(&sem->wait_lock, flags);
+	if (sem->counter > 0) {
+		sem->counter--;
+		success = 1;
+	}
+	spin_unlock_irqrestore(&sem->wait_lock, flags);
+	return !success;
+}
+
+static inline void up(struct semaphore *sem)
+{
+	unsigned long flags;
+
+#if SEMAPHORE_DEBUG
+	CHECK_MAGIC(sem->__magic);
+#endif
+
+	spin_lock_irqsave(&sem->wait_lock, flags);
+	if (!list_empty(&sem->wait_list))
+		__up(sem);
+	else
+		sem->counter++;
+	spin_unlock_irqrestore(&sem->wait_lock, flags);
+}
+
+static inline int sem_getcount(struct semaphore *sem)
+{
+	return sem->counter;
+}
+
+#endif /* __ASSEMBLY__ */
+
+#endif