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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-h8300/semaphore.h
downloadlinux-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
linux-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'include/asm-h8300/semaphore.h')
-rw-r--r--include/asm-h8300/semaphore.h194
1 files changed, 194 insertions, 0 deletions
diff --git a/include/asm-h8300/semaphore.h b/include/asm-h8300/semaphore.h
new file mode 100644
index 000000000000..fe6ef3774297
--- /dev/null
+++ b/include/asm-h8300/semaphore.h
@@ -0,0 +1,194 @@
+#ifndef _H8300_SEMAPHORE_H
+#define _H8300_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
+ *
+ * H8/300 version by Yoshinori Sato
+ */
+
+
+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);
+}
+
+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)
+{
+ register atomic_t *count asm("er0");
+
+ might_sleep();
+
+ count = &(sem->count);
+ __asm__ __volatile__(
+ "stc ccr,r3l\n\t"
+ "orc #0x80,ccr\n\t"
+ "mov.l %2, er1\n\t"
+ "dec.l #1,er1\n\t"
+ "mov.l er1,%0\n\t"
+ "bpl 1f\n\t"
+ "ldc r3l,ccr\n\t"
+ "mov.l %1,er0\n\t"
+ "jsr @___down\n\t"
+ "bra 2f\n"
+ "1:\n\t"
+ "ldc r3l,ccr\n"
+ "2:"
+ : "=m"(*count)
+ : "g"(sem),"m"(*count)
+ : "cc", "er1", "er2", "er3");
+}
+
+static inline int down_interruptible(struct semaphore * sem)
+{
+ register atomic_t *count asm("er0");
+
+ might_sleep();
+
+ count = &(sem->count);
+ __asm__ __volatile__(
+ "stc ccr,r1l\n\t"
+ "orc #0x80,ccr\n\t"
+ "mov.l %3, er2\n\t"
+ "dec.l #1,er2\n\t"
+ "mov.l er2,%1\n\t"
+ "bpl 1f\n\t"
+ "ldc r1l,ccr\n\t"
+ "mov.l %2,er0\n\t"
+ "jsr @___down_interruptible\n\t"
+ "bra 2f\n"
+ "1:\n\t"
+ "ldc r1l,ccr\n\t"
+ "sub.l %0,%0\n\t"
+ "2:\n\t"
+ : "=r" (count),"=m" (*count)
+ : "g"(sem),"m"(*count)
+ : "cc", "er1", "er2", "er3");
+ return (int)count;
+}
+
+static inline int down_trylock(struct semaphore * sem)
+{
+ register atomic_t *count asm("er0");
+
+ count = &(sem->count);
+ __asm__ __volatile__(
+ "stc ccr,r3l\n\t"
+ "orc #0x80,ccr\n\t"
+ "mov.l %3,er2\n\t"
+ "dec.l #1,er2\n\t"
+ "mov.l er2,%0\n\t"
+ "bpl 1f\n\t"
+ "ldc r3l,ccr\n\t"
+ "jmp @3f\n\t"
+ LOCK_SECTION_START(".align 2\n\t")
+ "3:\n\t"
+ "mov.l %2,er0\n\t"
+ "jsr @___down_trylock\n\t"
+ "jmp @2f\n\t"
+ LOCK_SECTION_END
+ "1:\n\t"
+ "ldc r3l,ccr\n\t"
+ "sub.l %1,%1\n"
+ "2:"
+ : "=m" (*count),"=r"(count)
+ : "g"(sem),"m"(*count)
+ : "cc", "er1","er2", "er3");
+ return (int)count;
+}
+
+/*
+ * 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)
+{
+ register atomic_t *count asm("er0");
+
+ count = &(sem->count);
+ __asm__ __volatile__(
+ "stc ccr,r3l\n\t"
+ "orc #0x80,ccr\n\t"
+ "mov.l %2,er1\n\t"
+ "inc.l #1,er1\n\t"
+ "mov.l er1,%0\n\t"
+ "ldc r3l,ccr\n\t"
+ "sub.l er2,er2\n\t"
+ "cmp.l er2,er1\n\t"
+ "bgt 1f\n\t"
+ "mov.l %1,er0\n\t"
+ "jsr @___up\n"
+ "1:"
+ : "=m"(*count)
+ : "g"(sem),"m"(*count)
+ : "cc", "er1", "er2", "er3");
+}
+
+#endif /* __ASSEMBLY__ */
+
+#endif