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authorDavid Howells <dhowells@redhat.com>2008-02-08 04:19:31 -0800
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2008-02-08 09:22:30 -0800
commitb920de1b77b72ca9432ac3f97edb26541e65e5dd (patch)
tree40fa9be1470e929c47927dea7eddf184c0204229 /include/asm-mn10300/semaphore.h
parentef3d534754f31fed9c3b976fee1ece1b3bc38282 (diff)
mn10300: add the MN10300/AM33 architecture to the kernel
Add architecture support for the MN10300/AM33 CPUs produced by MEI to the kernel. This patch also adds board support for the ASB2303 with the ASB2308 daughter board, and the ASB2305. The only processor supported is the MN103E010, which is an AM33v2 core plus on-chip devices. [akpm@linux-foundation.org: nuke cvs control strings] Signed-off-by: Masakazu Urade <urade.masakazu@jp.panasonic.com> Signed-off-by: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/asm-mn10300/semaphore.h')
-rw-r--r--include/asm-mn10300/semaphore.h169
1 files changed, 169 insertions, 0 deletions
diff --git a/include/asm-mn10300/semaphore.h b/include/asm-mn10300/semaphore.h
new file mode 100644
index 000000000000..5a9e1ad0b253
--- /dev/null
+++ b/include/asm-mn10300/semaphore.h
@@ -0,0 +1,169 @@
+/* MN10300 Semaphores
+ *
+ * Copyright (C) 2007 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 Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+#ifndef _ASM_SEMAPHORE_H
+#define _ASM_SEMAPHORE_H
+
+#ifndef __ASSEMBLY__
+
+#include <linux/linkage.h>
+#include <linux/wait.h>
+#include <linux/spinlock.h>
+#include <linux/rwsem.h>
+
+#define SEMAPHORE_DEBUG 0
+
+/*
+ * the semaphore definition
+ * - if count is >0 then there are tokens available on the semaphore for down
+ * to collect
+ * - if count 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 {
+ atomic_t count; /* it's not really atomic, it's
+ * just that certain modules
+ * expect to be able to access
+ * it directly */
+ 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, init_count) \
+{ \
+ .count = ATOMIC_INIT(init_count), \
+ .wait_lock = __SPIN_LOCK_UNLOCKED((name).wait_lock), \
+ .wait_list = LIST_HEAD_INIT((name).wait_list) \
+ __SEM_DEBUG_INIT(name) \
+}
+
+#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;
+ int count;
+
+#if SEMAPHORE_DEBUG
+ CHECK_MAGIC(sem->__magic);
+#endif
+
+ spin_lock_irqsave(&sem->wait_lock, flags);
+ count = atomic_read(&sem->count);
+ if (likely(count > 0)) {
+ atomic_set(&sem->count, count - 1);
+ spin_unlock_irqrestore(&sem->wait_lock, flags);
+ } else {
+ __down(sem, flags);
+ }
+}
+
+static inline int down_interruptible(struct semaphore *sem)
+{
+ unsigned long flags;
+ int count, ret = 0;
+
+#if SEMAPHORE_DEBUG
+ CHECK_MAGIC(sem->__magic);
+#endif
+
+ spin_lock_irqsave(&sem->wait_lock, flags);
+ count = atomic_read(&sem->count);
+ if (likely(count > 0)) {
+ atomic_set(&sem->count, count - 1);
+ 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 count, success = 0;
+
+#if SEMAPHORE_DEBUG
+ CHECK_MAGIC(sem->__magic);
+#endif
+
+ spin_lock_irqsave(&sem->wait_lock, flags);
+ count = atomic_read(&sem->count);
+ if (likely(count > 0)) {
+ atomic_set(&sem->count, count - 1);
+ 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
+ atomic_set(&sem->count, atomic_read(&sem->count) + 1);
+ spin_unlock_irqrestore(&sem->wait_lock, flags);
+}
+
+static inline int sem_getcount(struct semaphore *sem)
+{
+ return atomic_read(&sem->count);
+}
+
+#endif /* __ASSEMBLY__ */
+
+#endif