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>

1 files changed, 149 insertions, 0 deletions

diff --git a/arch/mn10300/kernel/semaphore.c b/arch/mn10300/kernel/semaphore.c
new file mode 100644
index 00000000000..9153c4039fd
--- /dev/null
+++ b/arch/mn10300/kernel/semaphore.c
@@ -0,0 +1,149 @@
+/* MN10300 Semaphore implementation
+ *
+ * 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.
+ */
+#include <linux/sched.h>
+#include <linux/module.h>
+#include <asm/semaphore.h>
+
+struct sem_waiter {
+	struct list_head	list;
+	struct task_struct	*task;
+};
+
+#if SEMAPHORE_DEBUG
+void semtrace(struct semaphore *sem, const char *str)
+{
+	if (sem->debug)
+		printk(KERN_DEBUG "[%d] %s({%d,%d})\n",
+		       current->pid,
+		       str,
+		       atomic_read(&sem->count),
+		       list_empty(&sem->wait_list) ? 0 : 1);
+}
+#else
+#define semtrace(SEM, STR) do { } while (0)
+#endif
+
+/*
+ * wait for a token to be granted from a semaphore
+ * - entered with lock held and interrupts disabled
+ */
+void __down(struct semaphore *sem, unsigned long flags)
+{
+	struct task_struct *tsk = current;
+	struct sem_waiter waiter;
+
+	semtrace(sem, "Entering __down");
+
+	/* set up my own style of waitqueue */
+	waiter.task = tsk;
+	get_task_struct(tsk);
+
+	list_add_tail(&waiter.list, &sem->wait_list);
+
+	/* we don't need to touch the semaphore struct anymore */
+	spin_unlock_irqrestore(&sem->wait_lock, flags);
+
+	/* wait to be given the semaphore */
+	set_task_state(tsk, TASK_UNINTERRUPTIBLE);
+
+	for (;;) {
+		if (!waiter.task)
+			break;
+		schedule();
+		set_task_state(tsk, TASK_UNINTERRUPTIBLE);
+	}
+
+	tsk->state = TASK_RUNNING;
+	semtrace(sem, "Leaving __down");
+}
+EXPORT_SYMBOL(__down);
+
+/*
+ * interruptibly wait for a token to be granted from a semaphore
+ * - entered with lock held and interrupts disabled
+ */
+int __down_interruptible(struct semaphore *sem, unsigned long flags)
+{
+	struct task_struct *tsk = current;
+	struct sem_waiter waiter;
+	int ret;
+
+	semtrace(sem, "Entering __down_interruptible");
+
+	/* set up my own style of waitqueue */
+	waiter.task = tsk;
+	get_task_struct(tsk);
+
+	list_add_tail(&waiter.list, &sem->wait_list);
+
+	/* we don't need to touch the semaphore struct anymore */
+	set_task_state(tsk, TASK_INTERRUPTIBLE);
+
+	spin_unlock_irqrestore(&sem->wait_lock, flags);
+
+	/* wait to be given the semaphore */
+	ret = 0;
+	for (;;) {
+		if (!waiter.task)
+			break;
+		if (unlikely(signal_pending(current)))
+			goto interrupted;
+		schedule();
+		set_task_state(tsk, TASK_INTERRUPTIBLE);
+	}
+
+ out:
+	tsk->state = TASK_RUNNING;
+	semtrace(sem, "Leaving __down_interruptible");
+	return ret;
+
+ interrupted:
+	spin_lock_irqsave(&sem->wait_lock, flags);
+	list_del(&waiter.list);
+	spin_unlock_irqrestore(&sem->wait_lock, flags);
+
+	ret = 0;
+	if (!waiter.task) {
+		put_task_struct(current);
+		ret = -EINTR;
+	}
+	goto out;
+}
+EXPORT_SYMBOL(__down_interruptible);
+
+/*
+ * release a single token back to a semaphore
+ * - entered with lock held and interrupts disabled
+ */
+void __up(struct semaphore *sem)
+{
+	struct task_struct *tsk;
+	struct sem_waiter *waiter;
+
+	semtrace(sem, "Entering __up");
+
+	/* grant the token to the process at the front of the queue */
+	waiter = list_entry(sem->wait_list.next, struct sem_waiter, list);
+
+	/* We must be careful not to touch 'waiter' after we set ->task = NULL.
+	 * It is an allocated on the waiter's stack and may become invalid at
+	 * any time after that point (due to a wakeup from another source).
+	 */
+	list_del_init(&waiter->list);
+	tsk = waiter->task;
+	smp_mb();
+	waiter->task = NULL;
+	wake_up_process(tsk);
+	put_task_struct(tsk);
+
+	semtrace(sem, "Leaving __up");
+}
+EXPORT_SYMBOL(__up);