[ARM] 3707/1: iwmmxt: use the generic thread notifier infrastructure

Patch from Lennert Buytenhek

This patch makes the iWMMXt context switch hook use the generic
thread notifier infrastructure that was recently merged in commit
d6551e884cf66de072b81f8b6d23259462c40baf.

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 64 insertions, 0 deletions

diff --git a/arch/arm/kernel/iwmmxt-notifier.c b/arch/arm/kernel/iwmmxt-notifier.c
new file mode 100644
index 00000000000..44a86c33796
--- /dev/null
+++ b/arch/arm/kernel/iwmmxt-notifier.c
@@ -0,0 +1,64 @@
+/*
+ *  linux/arch/arm/kernel/iwmmxt-notifier.c
+ *
+ *  XScale iWMMXt (Concan) context switching and handling
+ *
+ *  Initial code:
+ *  Copyright (c) 2003, Intel Corporation
+ *
+ *  Full lazy switching support, optimizations and more, by Nicolas Pitre
+ *  Copyright (c) 2003-2004, MontaVista Software, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <asm/thread_notify.h>
+#include <asm/io.h>
+
+static int iwmmxt_do(struct notifier_block *self, unsigned long cmd, void *t)
+{
+	struct thread_info *thread = t;
+
+	switch (cmd) {
+	case THREAD_NOTIFY_FLUSH:
+		/*
+		 * flush_thread() zeroes thread->fpstate, so no need
+		 * to do anything here.
+		 *
+		 * FALLTHROUGH: Ensure we don't try to overwrite our newly
+		 * initialised state information on the first fault.
+		 */
+
+	case THREAD_NOTIFY_RELEASE:
+		iwmmxt_task_release(thread);
+		break;
+
+	case THREAD_NOTIFY_SWITCH:
+		iwmmxt_task_switch(thread);
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block iwmmxt_notifier_block = {
+	.notifier_call	= iwmmxt_do,
+};
+
+static int __init iwmmxt_init(void)
+{
+	thread_register_notifier(&iwmmxt_notifier_block);
+
+	return 0;
+}
+
+late_initcall(iwmmxt_init);