1 files changed, 54 insertions, 0 deletions
diff --git a/arch/sh/kernel/return_address.c b/arch/sh/kernel/return_address.c
new file mode 100644
index 000000000000..df3ab5811074
--- /dev/null
+++ b/arch/sh/kernel/return_address.c
@@ -0,0 +1,54 @@
+/*
+ * arch/sh/kernel/return_address.c
+ *
+ * Copyright (C) 2009  Matt Fleming
+ * Copyright (C) 2009  Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/kernel.h>
+#include <asm/dwarf.h>
+
+#ifdef CONFIG_DWARF_UNWINDER
+
+void *return_address(unsigned int depth)
+{
+	struct dwarf_frame *frame;
+	unsigned long ra;
+	int i;
+
+	for (i = 0, frame = NULL, ra = 0; i <= depth; i++) {
+		struct dwarf_frame *tmp;
+
+		tmp = dwarf_unwind_stack(ra, frame);
+
+		if (frame)
+			dwarf_free_frame(frame);
+
+		frame = tmp;
+
+		if (!frame || !frame->return_addr)
+			break;
+
+		ra = frame->return_addr;
+	}
+
+	/* Failed to unwind the stack to the specified depth. */
+	WARN_ON(i != depth + 1);
+
+	if (frame)
+		dwarf_free_frame(frame);
+
+	return (void *)ra;
+}
+
+#else
+
+void *return_address(unsigned int depth)
+{
+	return NULL;
+}
+
+#endif