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-rw-r--r--include/asm-m32r/semaphore.h205
1 files changed, 205 insertions, 0 deletions
diff --git a/include/asm-m32r/semaphore.h b/include/asm-m32r/semaphore.h
new file mode 100644
index 000000000000..53e3c60f21ec
--- /dev/null
+++ b/include/asm-m32r/semaphore.h
@@ -0,0 +1,205 @@
+#ifndef _ASM_M32R_SEMAPHORE_H
+#define _ASM_M32R_SEMAPHORE_H
+
+#include <linux/linkage.h>
+
+#ifdef __KERNEL__
+
+/*
+ * SMP- and interrupt-safe semaphores..
+ *
+ * Copyright (C) 1996 Linus Torvalds
+ * Copyright (C) 2004 Hirokazu Takata <takata at linux-m32r.org>
+ */
+
+#include <linux/config.h>
+#include <linux/wait.h>
+#include <linux/rwsem.h>
+#include <asm/assembler.h>
+#include <asm/system.h>
+#include <asm/atomic.h>
+
+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 __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);
+ *
+ * i'd rather use the more flexible initialization above, but sadly
+ * GCC 2.7.2.3 emits a bogus warning. EGCS doesnt. Oh well.
+ */
+ atomic_set(&sem->count, val);
+ sem->sleepers = 0;
+ init_waitqueue_head(&sem->wait);
+}
+
+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);
+
+/*
+ * Atomically decrement the semaphore's count. If it goes negative,
+ * block the calling thread in the TASK_UNINTERRUPTIBLE state.
+ */
+static inline void down(struct semaphore * sem)
+{
+ unsigned long flags;
+ long count;
+
+ might_sleep();
+ local_irq_save(flags);
+ __asm__ __volatile__ (
+ "# down \n\t"
+ DCACHE_CLEAR("%0", "r4", "%1")
+ M32R_LOCK" %0, @%1; \n\t"
+ "addi %0, #-1; \n\t"
+ M32R_UNLOCK" %0, @%1; \n\t"
+ : "=&r" (count)
+ : "r" (&sem->count)
+ : "memory"
+#ifdef CONFIG_CHIP_M32700_TS1
+ , "r4"
+#endif /* CONFIG_CHIP_M32700_TS1 */
+ );
+ local_irq_restore(flags);
+
+ if (unlikely(count < 0))
+ __down(sem);
+}
+
+/*
+ * Interruptible try to acquire a semaphore. If we obtained
+ * it, return zero. If we were interrupted, returns -EINTR
+ */
+static inline int down_interruptible(struct semaphore * sem)
+{
+ unsigned long flags;
+ long count;
+ int result = 0;
+
+ might_sleep();
+ local_irq_save(flags);
+ __asm__ __volatile__ (
+ "# down_interruptible \n\t"
+ DCACHE_CLEAR("%0", "r4", "%1")
+ M32R_LOCK" %0, @%1; \n\t"
+ "addi %0, #-1; \n\t"
+ M32R_UNLOCK" %0, @%1; \n\t"
+ : "=&r" (count)
+ : "r" (&sem->count)
+ : "memory"
+#ifdef CONFIG_CHIP_M32700_TS1
+ , "r4"
+#endif /* CONFIG_CHIP_M32700_TS1 */
+ );
+ local_irq_restore(flags);
+
+ if (unlikely(count < 0))
+ result = __down_interruptible(sem);
+
+ return result;
+}
+
+/*
+ * Non-blockingly attempt to down() a semaphore.
+ * Returns zero if we acquired it
+ */
+static inline int down_trylock(struct semaphore * sem)
+{
+ unsigned long flags;
+ long count;
+ int result = 0;
+
+ local_irq_save(flags);
+ __asm__ __volatile__ (
+ "# down_trylock \n\t"
+ DCACHE_CLEAR("%0", "r4", "%1")
+ M32R_LOCK" %0, @%1; \n\t"
+ "addi %0, #-1; \n\t"
+ M32R_UNLOCK" %0, @%1; \n\t"
+ : "=&r" (count)
+ : "r" (&sem->count)
+ : "memory"
+#ifdef CONFIG_CHIP_M32700_TS1
+ , "r4"
+#endif /* CONFIG_CHIP_M32700_TS1 */
+ );
+ local_irq_restore(flags);
+
+ if (unlikely(count < 0))
+ result = __down_trylock(sem);
+
+ 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)
+{
+ unsigned long flags;
+ long count;
+
+ local_irq_save(flags);
+ __asm__ __volatile__ (
+ "# up \n\t"
+ DCACHE_CLEAR("%0", "r4", "%1")
+ M32R_LOCK" %0, @%1; \n\t"
+ "addi %0, #1; \n\t"
+ M32R_UNLOCK" %0, @%1; \n\t"
+ : "=&r" (count)
+ : "r" (&sem->count)
+ : "memory"
+#ifdef CONFIG_CHIP_M32700_TS1
+ , "r4"
+#endif /* CONFIG_CHIP_M32700_TS1 */
+ );
+ local_irq_restore(flags);
+
+ if (unlikely(count <= 0))
+ __up(sem);
+}
+
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_M32R_SEMAPHORE_H */